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Background: An anterior cruciate ligament (ACL) injury accompanied by patellar instability (PI) is a topic that has gained orthopaedic surgeons' attention recently. Untreated PI is reportedly associated with worse clinical outcomes after isolated ACL reconstruction (ACLR) in patients after an ACL injury with PI. Nevertheless, the appropriate surgical approach and its long-term therapeutic effects in these patients remain unclear. Purpose: (1) To compare the clinical and radiological outcomes between isolated ACLR (iACLR) and combined ACLR and medial patellofemoral ligament reconstruction (cAMR) in patients after an ACL injury with PI and (2) to explore the correlations between these 2 procedures and clinical and radiological outcomes. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 106 patients diagnosed with an ACL injury accompanied by PI between January 2016 and April 2021 were analyzed in this study. There were 34 patients excluded because of missing postoperative radiological data. Among the remaining 72 patients, 34 patients underwent iACLR, while 38 patients underwent cAMR. Demographic characteristics, intraoperative findings, and patient-reported outcomes (Lysholm score, subjective International Knee Documentation Committee score, and Tegner activity score) were prospectively collected. Patellar alignment parameters and worsening patellofemoral osteoarthritis (PFOA) features (evaluated with the modified Whole-Organ Magnetic Resonance Imaging Score) were analyzed longitudinally on magnetic resonance imaging. The Kujala score was used to evaluate the functional recovery of the patellofemoral joint, and redislocations of the patella were prospectively recorded. Finally, multivariate logistic regression analysis was used to explore the correlations between these 2 procedures and clinical (not achieving the minimal detectable change [MDC] for the Lysholm score) and radiological (worsening PFOA features) outcomes. Results: The mean follow-up duration was 28.9 ± 6.2 and 27.1 ± 6.8 months for the iACLR and cAMR groups, respectively (P =.231). Significantly higher Lysholm scores (88.3 ± 9.9 vs 82.1 ± 11.1, respectively; P =.016) and subjective International Knee Documentation Committee scores (83.6 ± 11.9 vs 78.3 ± 10.2, respectively; P =.046) were detected in the cAMR group compared with the iACLR group postoperatively. The rates of return to preinjury sports were 20.6% and 44.7% in the iACLR and cAMR groups, respectively (difference, 24.1% [95% CI, 3.3%-45.0%]; P =.030). Moreover, the rates of worsening PFOA features were 44.1% and 18.4% in the iACLR and cAMR groups, respectively (difference, 25.7% [95% CI, 4.9%-46.4%]; P =.018). In addition, significantly higher Kujala scores (87.9 ± 11.3 vs 80.1 ± 12.0, respectively; P =.006), lower redislocation rates (0.0% vs 11.8%, respectively; difference, 11.8% [95% CI, 0.9%-22.6%]; P =.045), and significantly better patellar alignment were detected in the cAMR group compared with the iACLR group postoperatively. Furthermore, multivariate logistic regression analysis determined that iACLR and partial lateral meniscectomy were significantly correlated with not achieving the MDC for the Lysholm score and worsening PFOA features in our study population. Conclusion: In patients after an ACL injury with PI, cAMR yielded better clinical and radiological outcomes compared with iACLR, with better patellar stability and a lower proportion of worsening PFOA features. Furthermore, not achieving the MDC for the Lysholm score and worsening PFOA features were significantly correlated with iACLR and partial lateral meniscectomy. Our study suggests that cAMR may be a more appropriate procedure for patients after an ACL injury with PI, which warrants further high-level clinical evidence. [ABSTRACT FROM AUTHOR]

Background-oriented Schlieren tomography (BOST) is widely used for 3D reconstruction of turbulent flames. Two major concerns are associated with 3D reconstruction. One is the time asynchrony within the data acquisition of the high-speed camera. The other is that the ray tracing process requires significant computational consumption. This study proposes a ray tracing optimization method based on the k-d tree. The study results show that the average search nodes for each ray are only 0.018% of 3D flame with 3.07 million grid nodes. In addition, a parameter estimation method of the unknown azimuth power spectrum function is proposed. First, a typical Sandia turbulent jet diffusion flame dataset was built and validated accordingly, with experiments. The algorithm's applicability to the 3D reconstruction of temperature and density fields is discussed on this basis. The root-mean-square error (RMSE) of the cross-section density for 3D reconstruction is below 0.1 kg/m3. In addition, the RMSE of the cross-section temperature is below 270 K. Finally, an uncertainty analysis of the flame reconstruction based on a physical model is performed by optimizing the ray tracing method. For the time asynchronous variance of 1 ms, the density uncertainty of the 3D reconstruction is below 1.6 × 10−2 kg/m3, and the temperature uncertainty is below 70 K. The method can provide an essential basis for the design of BOST systems and the 3D reconstruction of turbulent flames. [ABSTRACT FROM AUTHOR]

Objective: To propose a novel morphological classification method for notches, which may provide new evidence for notchplasty based on the three-dimensional (3D) features of notches and the risk of anterior cruciate ligament (ACL) injury.Materials and Methods: Three hundred individuals in total were included in our study, including 150 patients with ACL ruptures (75 males and 75 females) and 150 age- and gender-matched individuals without ACL ruptures. The notches were divided into four types according to the notch widths at the notch inlet, outlet, and ACL attachment based on the preoperative MRI, the notch volume was calculated, and the risk of ACL injury was compared. The surgical records were reviewed and whether these cases performed notchplasty were collected.Results: The inlet-and-outlet stenosis notch type was associated with smaller notch volume (P = 0.007) and a higher risk of ACL injury (P < 0.001). There were no significant differences in morphological distribution between males and females. The rate of notchplasty in inlet-and-outlet stenosis type was higher than the others.Conclusions: The new morphological classification method efficiently reflected the association of the notch shape with the 3D notch volume and the risk of ACL injury. The knees with the inlet-and-outlet stenosis notch type and smaller notch volume tended to have a higher risk of ACL injury. Level of evidence Level III, case-control study. [ABSTRACT FROM AUTHOR]

Insects are the most diverse group of organisms in the animal kingdom, and some species exhibit complex social behaviors. Although research on insect object use is still in its early stages, insects have already been shown to display rich object‐use behaviors. This review focuses on patterns and behavioral flexibility in insect object‐use behavior, and the role of cultural evolution in the development of object‐use behaviors. Object use in insects is not widespread but has been documented in a diverse set of taxa. Some insects can use objects flexibly and display various object‐use patterns. Like mammals and birds, insects use objects in diverse activities, including foraging, predator defense, courtship, and play. Intelligence, pre‐existing manipulative behaviors, and anatomical structure affect innovations in object use. In addition, learning and imitation are the main mechanisms underlying the spread of object‐use behaviors within populations. Given that insects are one of the major animal groups engaging in object use, studies of insect object use could provide general insights into object use in the animal kingdom. [ABSTRACT FROM AUTHOR]

Background: Rotator cuff tear size, fatty infiltration, and scapular morphology are correlated with tendon healing and functional outcomes after arthroscopic repair; however, the association between anteroposterior acromial coverage and the clinical outcomes of anteroposterior massive rotator cuff tears (AP-MRCTs; involving all 3 tendons) remains unclear. Purpose: To identify the association between AP acromial coverage and functional and radiological outcomes after arthroscopic repair of AP-MRCTs. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 98 patients who underwent arthroscopic repair of AP-MRCTs between January 2015 and December 2020 were included in the study and classified according to whether anterior acromial coverage (AAC) was anterior (46 patients; positive AAC group) or posterior (52 patients; negative AAC group) to the scapular line on true lateral shoulder radiographs. Demographic characteristics, surgical details, and functional outcomes were prospectively collected. Acromial morphological features, global tear extension (GTE), the global fatty infiltration index (GFII), tendon integrity after repair, proximal humeral migration, and glenohumeral abduction were measured and calculated on radiographs or magnetic resonance imaging scans preoperatively and at 2 years postoperatively. Multivariate logistic regression was performed to identify the independent risk factors of a rotator cuff retear. Results: The positive AAC group showed larger AAC, posterior acromial tilt, and anterior acromial slope as well as smaller posterior acromial coverage compared with the negative AAC group. Postoperatively, the American Shoulder and Elbow Surgeons score (82.5 ± 8.3 vs 77.2 ± 11.5, respectively; P =.013), active abduction (157.8°± 27.1° vs 142.7°± 39.6°, respectively; P =.048), and glenohumeral abduction (45.6°± 10.4° vs 39.7°± 14.9°, respectively; P =.041) in the positive AAC group were significantly higher than those in the negative AAC group, while the retear rate (23.9% vs 44.2%, respectively; P =.035) and proximal humeral migration (1.7 ± 1.0 vs 2.3 ± 1.2 mm, respectively; P =.006) were significantly lower in the positive AAC group than in the negative AAC group. Smaller AAC (odds ratio [OR], 0.93 [95% CI, 0.87-1.00]; P =.040), larger GTE (OR, 1.03 [95% CI, 1.01-1.06]; P =.017), and a higher GFII (OR, 3.49 [95% CI, 1.09-11.19]; P =.036) were associated with an increased risk of a rotator cuff retear. Conclusion: Increased AAC was associated with a lower retear rate and better functional outcomes after arthroscopic repair of AP-MRCTs. A preliminary risk evaluation integrating GTE, the GFII, and AAC is recommended to consider the necessity of additional procedures for patients in need of arthroscopic rotator cuff repair. [ABSTRACT FROM AUTHOR]

To understand effects of soil microbes on soil biochemistry in alpine grassland ecosystems under environmental changes, we explored relationships between soil microbial diversity and soil total nitrogen, organic carbon, available nitrogen and phosphorus, soil microbial biomass and soil enzyme activities in alpine meadow, alpine steppe and cultivated grassland on the Qinghai-Tibetan plateau under three-year warming, enhanced precipitation and yak overgrazing. Soil total nitrogen, organic carbon and NH4-N were little affected by overgrazing, warming or enhanced precipitation in three types of alpine grasslands. Soil microbial biomass carbon and phosphorus along with the sucrase and phosphatase activities were generally stable under different treatments. Soil NO3-N, available phosphorus, urease activity and microbial biomass nitrogen were increased by overgrazing in the cultivated grassland. Soil bacterial diversity was positively correlated with, while soil fungal diversity negatively with soil microbial biomass and enzyme activities. Soil bacterial diversity was negatively correlated with, while soil fungal diversity positively with soil available nutrients. Our findings indicated soil bacteria and fungi played different roles in affecting soil nutrients and microbiological activities that might provide an important implication to understand why soil biochemistry was generally stable under environmental changes in alpine grassland ecosystems. [ABSTRACT FROM AUTHOR]

Highlights • A time-saving model was proposed for predicting plume's infrared thermal radiations. • An assessment of computational error and efficiency was made. • Flow properties of plumes in the full domain were examined. • Radiation characteristics were obtained numerically. • A relationship between the cutoff temperature and plume's length was shown. Abstract In this paper, a fast estimating method of thermal infrared radiation signatures for low-altitude exhaust plumes was proposed. In engineering application, it is essential to predict the thermal radiation effect of the plume as soon as possible. A simple numerical model was established considering thermal, species formation, entrainment and radiating effects. In this methodology, the mixing region was treated as a hot, under-expanded, reacting and isotonic flow. The reacting flows were simulated by solving the governing equations with finite rate kinetics and conservation matching relations. A single-line-group (SLG) model with Curtis-Godson approximation was utilized to evaluate radiative properties of radiating species. A line-of-sight (LOS) method was used to compute the spectral radiation intensity. This computational model was verified against the Atlas-II's reference data within the wavelengths of 2–6 μm. The simulation analyzed combustion flows and infrared thermal effects of a typical exhaust plume along flight trajectory points. Results show that the current model can dramatically improve the computational efficiency by 100–1000 times by comparing with the commonly used method. According to this model, the plume's range and an appropriable cutoff temperature for thermal radiation calculations are easy to obtain. Infrared radiation phenomena accord with the experimental observations. As a main outcome, this simple model can provide a time-saving and range-unlimited method for the infrared radiation signature prediction of a low-altitude plume in engineering application. [ABSTRACT FROM AUTHOR]

Highlights • The accuracy of various WSGG models is evaluated against line-by-line approach. • The computational applicability and reliability of WSGG models are analyzed in a 600 kW furnace. • Both non-gray and gray modelling approaches are analyzed. • Non-gray approach is much closer agreement to experimental and detailed modelling results. Abstract Radiative heat transfer plays an important role in combustion systems. Good compromise between the accuracy and computational requirements of the weighted sum of gray gases (WSGG) model makes it widely used in CFD simulations. In this paper, the accuracy of various WSGG models is assessed by the comparison with the results of radiative heat source and heat flux calculated by line by line (LBL) approach in a realistic non-isothermal and non-homogeneous flame using decoupled calculations. Then these models are implemented to CFD code to investigate the radiative heat transfer for a 600 kW furnace using coupled calculations. The experimental data from the furnace has been used to evaluate the computational applicability and reliability of WSGG models. Results show that the non-gray formulation of WSGG model is more accurate than gray modelling approach, compared with LBL results. The non-gray WSGG models of Krishnamoorthy et al. (2013), Bordbar et al. (2014) and Shan et al. (2018) provide the minimal overall errors compared with the measured temperature fields. The results demonstrate that using the non-gray approach instead of gray approach for global CFD simulation improves the simulation accuracy of thermal radiation transfer. The computing time of non-gray models is larger, approximately 3–4 times that of gray WSGG models. [ABSTRACT FROM AUTHOR]

Abstract As the core component of the micro thermophotovoltaic (MTPV) system, the micro combustor with a high and uniform wall temperature distribution is beneficial to improve the energy conversion efficiency. In this paper, a micro tube combustor with converging-diverging channel is proposed and the thermal performance is numerically investigated, compared with that of the micro combustor with cylindrical channel. The effects of inlet velocity of H 2 /air mixture, dimensionless position and diameter of throat, and solid material on the thermal performance are widely analyzed. Results show that the outer wall temperature and emitter efficiency of the micro combustor with converging-diverging channel are higher than that of the micro combustor with cylindrical channel, and the converging-diverging channel has more uniform temperature distribution. The converging-diverging micro combustor with dimensionless throat position l = 0.375 and dimensionless throat diameter β = 0.4 is more suitable for the application of MTPV system. When H 2 /air inlet velocity is 11 m/s and H 2 /air equivalence ratio is 1.0, the mean wall temperature is increased by 82.39 K and the emitter efficiency is increased by 6.59%, while the normalized temperature standard deviation is reduced by 65.85%. Additionally, the use of SiC as wall material can improve the thermal performance of the micro combustor. It is worth noting that this work will offer us significant guidelines for the optimized work of micro tube combustor. Highlights • A micro tube combustor with converging-diverging channel is proposed. • Effects of diameters and locations of throat on the thermal performance are investigated. • Converging-diverging micro combustor has a higher and more uniform wall temperature due to the enhanced heat transfer. • Solid material with higher thermal conductivity and emissivity is more suitable for the developed combustor. [ABSTRACT FROM AUTHOR]

Predicting thermal radiation for turbulent combustion highlights the significance of turbulence radiation interactions (TRI). Thermal radiation behaviors of methane/hydrogen flames under elevated pressures are investigated numerically using the developed TRI module integrated into CFD codes. The updated non-gray weighted sum of gray gases model is used to calculate the radiative properties of participating media. TRI effects have been analyzed with 0%–50% volumetric fraction of hydrogen in the methane/hydrogen blended fuels under 1–5 atm working pressures. Employing the radiation model considering TRI achieves closer predicted consistency to the experimental data. Only thermal radiation makes the flame temperature dropped about 60–140 K, while the predicted radiative source term calculated with TRI is higher than that without TRI, which results in a colder flame (approximately 13–60 K lower). The impact of TRI on the radiation behavior is enhanced in hydrogen-enriched high-pressure flame as the predicted radiation heat flux and radiative source term are increased above 25% than that without TRI. On account of TRI effect, the net radiative heat loss increases almost 50% at elevated pressure. The strong radiation of participating media in methane/hydrogen flames under elevated pressures emphasizes the importance of TRI effect on accurate predictions of thermal radiation and NO emission. [ABSTRACT FROM AUTHOR]

Purpose: To compare the midterm clinical outcomes of different meniscal surgeries in patients undergoing anatomic double-bundle anterior cruciate ligament reconstruction (DB-ACLR) with eight strands of hamstring (HT8) autografts and explore the potential predictive risk factors for residual knee laxity. Methods: From 2010 to 2017, a total of 410 patients who underwent anatomic trans-tibial DB-ACLR with HT8 autografts (169 patients without meniscal surgery, 105 patients with meniscal repair, and 136 patients with meniscal resection) were included in this study. The equivalent graft diameter was introduced to make the total graft size of DB-ACLR comparable with that of single-bundle ACLR and calculated as the square root of the quadratic sum of the diameter for each bundle. Residual laxity was defined as excessive anterior tibial translation or residual pivot shift at any follow-up visit, while graft rupture was confirmed by second-look arthroscopy or magnetic resonance imaging. Results: The mean follow-up period was 8.3 ± 2.2 years. The mean equivalent graft diameter was 9.9 ± 0.7 mm. Graft rupture was confirmed in 16 (3.9%) patients, while residual laxity was detected in 72 (17.6%) patients (34 [25.0%] in the meniscal resection group vs. 22 [13.0%] in the no meniscal surgery group, p = 0.021). In the multivariate logistic regression analysis, high-grade preoperative knee laxity (odds ratio OR 2.04, p = 0.020), equivalent graft diameter < 9 mm (OR 3.31 compared with 9–10 mm, p = 0.012; OR 3.28 compared with ≥ 10 mm, p = 0.019), and meniscal resection (OR 1.94 compared with no meniscal surgery, p = 0.045) were associated with residual laxity. Conclusion: During a midterm follow-up, meniscal resection increased the risk of residual knee laxity even in patients undergoing anatomic DB-ACLR with HT8 autografts. Increasing the hamstring graft diameter and preserving the menisci are important strategies for ACLR to restore knee stability. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Over the last 40 years, a burrowing mammal eradication policy has been prevalent on the Qinghai–Tibetan Plateau (QTP). This policy is based on similar burrowing mammal eradication programs in other areas and is justified on the assumptions that burrowing mammals compete with livestock for forage and contribute to grassland degradation. However, there is no clear theoretical or experimental evidence supporting these assumptions.This paper synthesizes the ecological functioning of small burrowing mammals in natural grasslands and discusses the irrationality and consequences of burrowing mammal eradication for sustainable livestock grazing and grassland degradation.Past burrowing mammal eradication efforts have failed because increased food availability for the remaining rodents and reduced predator populations led to rapid population rebounds. Herbivores differ in diet, and there is clear evidence that burrowing mammals, especially plateau zokors Myospalax baileyi, have a different diet than livestock. In QTP meadows, burrowing mammal eradication induces a shift towards plant communities with fewer species preferred by livestock and more species preferred by burrowing mammals. Thus, eradicating burrowing mammals has the opposite effect, a reduction in livestock preferred vegetation. We suggest that the policy of poisoning burrowing mammals needs to be reconsidered and revoked as soon as possible.We argue that incorporating density‐dependent factors such as predation and food availability are essential for maintaining a low burrowing mammal density. For degraded grasslands, we suggest that the optimal sustainable approach is to decrease the intensity of livestock grazing. Lower grazing induces changes in vegetation structure and plant species composition that increases predation on burrowing mammals and decreases the abundance of plants preferred by burrowing mammals. Such a nature‐based grassland management system maintains the density of burrowing mammals at a low stable density while minimizing human management and interventions. [ABSTRACT FROM AUTHOR]

The livestock depredation by large carnivores is a main cause for increasing human–wildlife conflicts (HWCs) and is one of the prime challenges for carnivore's conservation and a major economic concern to livestock‐dependent communities around wildlife habitats. Thus, understanding the patterns and trends of livestock depredation may contribute to better understanding of the mechanisms underlying HWCs and to mitigating HWCs. HWCs characterized by livestock depredation by large carnivores are prevalent in northern Pakistan, but the underlying mechanisms are poorly investigated. This study was conducted in 2018 in the Khunjerab Valley and Shimshal Valley of the Pamir region to evaluate the spatial and seasonal variation and impact of livestock depredation by carnivores. Data were collected on livestock depredation and its associated economic impact through semi‐structured interviews of randomly selected households in the two valleys. The livestock in Shimshal Valley was more susceptible to large carnivores' depredation (233 heads per year) than in Khunjerab Valley (125 heads per year). This spatial variation in livestock depredation was reflective of the difference in the socio‐economic conditions and physical locations between the two valleys. More livestock depredation took place in winter in Khunjerab Valley, while more livestock depredation occurred in summer in Shimshal Valley, mainly because of different grazing systems in the two valleys. The total economic loss incurred due to large carnivores' depredation was US$ 76,063 in Shimshal Valley, as compared to US$ 34,175 in Khunjerab Valley in 2018. The average economic loss per household was US$ 950.8, accounting for nearly 30% of the household annual income in Shimshal Valley in 2018. A higher proportion of participants in Shimshal Valley (83%) in comparison to Khunjerab Valley (69%) expressed a negative attitude towards wild carnivores. The study concludes that Shimshal Valley, remotely located and having comparatively marginal income opportunities, was more reliant on agro‐pastoralism and thus more vulnerable to the economic repercussions of livestock depredation by wild carnivores. Thus, such measures as improvement in road transportation and livestock management are in urgent need to better manage HWCs in Shimshal Valley. [ABSTRACT FROM AUTHOR]

Background: High-grade knee laxity and excessive anterior tibial subluxation (ATS) are correlated with poor clinical outcomes in patients with anterior cruciate ligament (ACL) deficiency and share similar risk factors; however, the association between excessive ATS and high-grade knee laxity remains unclear. Purpose: To identify the association between excessive ATS and high-grade knee laxity in patients with ACL deficiency and determine the possibility that ATS can predict high-grade knee laxity. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 226 patients who underwent ACL reconstruction between May 2018 and March 2022 were analyzed in the present study; the high-grade group consisted of 113 patients who had a grade 3 result on the preoperative anterior drawer test, Lachman test, or pivot-shift test while under anesthesia, and the low-grade group consisted of 113 matched patients. The ATS values for medial and lateral compartments (ATSMC and ATSLC) were measured on magnetic resonance imaging while patients relaxed the quadriceps in the supine position under no anesthesia. The optimal cutoff values of ATSMC and ATSLC for high-grade knee laxity were determined using receiver operating characteristic curves. Univariate and multivariate logistic regression analyses with stratification were performed to identify the association between excessive ATS and high-grade knee laxity. Results: Compared with the low-grade group, the high-grade group had a longer time from injury to surgery; higher rates of medial meniscus posterior horn tear (MMPHT), lateral meniscus posterior horn tear (LMPHT), and anterolateral ligament (ALL) abnormality; and larger lateral tibial slope, ATSMC, and ATSLC. The optimal cutoff value was 2.6 mm (sensitivity, 52.2%; specificity, 76.1%) for ATSMC and 4.5 mm (sensitivity, 67.3%; specificity, 64.6%) for ATSLC in predicting high-grade knee laxity. After adjustment for covariates, ATSLC ≥4.5 mm (odds ratio [OR], 2.94; 95% CI, 1.56-5.55; P =.001), MMPHT (OR, 2.62; 95% CI, 1.35-5.08; P =.004), LMPHT (OR, 2.39; 95% CI, 1.20-4.78; P =.014), and ALL abnormality (OR, 2.09; 95% CI, 1.13-3.89; P =.019) were associated with high-grade knee laxity. The association between excessive ATSLC and high-grade knee laxity was validated in patients with acute ACL injury as well as those with chronic ACL injury. Conclusion: Excessive ATSLC was associated with high-grade knee laxity in patients who had ACL deficiency, with a predictive cutoff value of 4.5 mm. This study may help surgeons estimate the degree of knee instability more accurately before anesthesia and may facilitate preliminary surgical decision-making, such as appropriate graft choices and consideration of extra-articular augmentation. [ABSTRACT FROM AUTHOR]

Construction and operation of cascading dams can pose drastic effects on sediment transport and deposition, thus affecting sedimentary carbon concentrations in the riverine ecosystem. This paper examines the spatial variations of sedimentary organic carbon (OC sed ) and its potential relationship with terrestrial soil loss in two cascade reservoirs (Manwan and Dachaoshan) along the mainstream of Lancang River. During both wet and dry seasons in 2013 and 2014, 25 sampling sections were chosen to evaluate the spatial variations of sedimentary organic carbon. Generally, the contents of OC sed in the upper 5 cm of the bottom sediment in wet seasons were higher than those in dry seasons in both reservoirs. Spatially, lower reservoir (Dachaoshan) preserved higher OC sed content than the upper reservoir (Manwan), at 36.1 kg m −2 and 27.8 kg m −2 , respectively. Additionally, the contents of OC sed in the reservoir heads were higher than those in the reservoir centres and tails, this trend was also observed for terrestrial organic carbon (OC ter ) and liable organic carbon (LOC). Hillslope delivery ratio (HSDR) method are used to estimate the incoming sediment yields from the river basin. The results indicated that Dachaoshan catchment generated higher sediment stream deposits than the Manwan catchment with the high sediment loading (>40 t/ha/year) areas located within 3 km buffers encompassing a higher accumulation of farmlands. The cumulative effects of sediment transport on OC sed along the river channel were further investigated by setting sequential riverine sediment delivery ratios (0–0.55) to explore potential relationships between OC sed and total sediment delivered to stream. The results showed that in the Dachaoshan Reservoir the OC sed contents correlated with the total sediment delivered to streams when the ratios ranged from 0.10 to 0.55, in particular in delivery ratios ranging from 0.50 to 0.55. These findings emphasized the importance of direct and indirect connections between the terrestrial and riverine ecosystems, and also provided a preferable view to understand the cumulative effects of sediment transport on OC sed distributions in the reservoirs generated by cascading dams. [ABSTRACT FROM AUTHOR]

• Grazing reduced the temporal stability of ANPP. • Grazing increased the stability of productivity of functional group of forbs. • The response species to continuous grazing are mainly grasses. • The response species to rotational grazing are forbs. • Functional groups asynchrony stabilized ANPP under grazing in the Qinghai-Tibetan Plateau. The stability of grassland is pivotal in maintaining the grassland functioning and services. However, the knowledge about the consequences of grazing on stability of grassland productivity is limited. Based on a 3-year manipulated experiment with two grazing regimes (i.e., continuous grazing and rotational grazing) along four levels of grazing-intensity (0, 4, 6, and 8 sheep per hectare) on the Qinghai-Tibetan Plateau, we researched the responses of temporal stability of plant community and functional groups of alpine grasslands to different grazing management regimes. We found that grazing regimes, intensity and their interaction affected the temporal stability of aboveground net primary productivity of alpine grassland (ANPP), and intermediate rotational grazing significantly reduced the temporal stability of ANPP, whereas increased the stability of productivity of functional group of forbs. The response species to continuous grazing and rotational grazing are different, for grasses and forbs respectively. Rotational grazing and intermediate continuous grazing increased the diversity of response species. Structural equation modeling further revealed that functional groups asynchrony stabilized the productivity of the alpine grassland ecosystem under grazing in the Qinghai-Tibetan Plateau. These results showed that the rotational grazing and intermediate continuous grazing can maintain the productivity stability, and highlighted importance of regulating the relationships among functional groups for promoting the stability of alpine grassland under grazing management. [ABSTRACT FROM AUTHOR]

A hypersonic electromagnetic railgun projectile undergoes severe aero-heating with an increase in altitude. The purpose of this study was to investigate the characteristics of the shock layer flow field as well as the thermal environment of the blunt body wall of a hypersonic electromagnetic railgun projectile at different launching angles. The two-temperature model considers the thermal nonequilibrium effect and is introduced into the Navier–Stokes (N-S) equation, and it is solved using the finite volume method (FVM). The reliability of the calculation model in terms of thermal properties and composition production was verified against a blunted-cone-cylinder–flare (HB-2) test case. The surface temperature of the hypersonic blunt projectile was simulated using a radiation balance wall boundary. The thermal characteristics at the emission angles α = 60° and α = 45° were checked within an altitude range of 0–70 km, including the nonequilibrium effect, reaction heat release, aerodynamic heat flux, and wall temperature. The results show that the translational rotational temperature is higher than the vibrational electronic temperature, and the thermal nonequilibrium effect increases with an increase in altitude. Comparing the two launching angles, the nonequilibrium degree and reaction heat release at α = 60° were higher than those at α = 45°. The rates of exothermic reaction decreased with an increase in altitude. The heat flux along the wall of the generatrix decreased sharply from the stagnation point. With an increase in altitude, the heat flux dropped sharply from 7 MW/m2 at H = 0 km to approximately 2 MW/m2 at H = 70 km. The wall temperature distribution was similar to the heat flux distribution; however, the surface temperature decreased less rapidly than the heat flux. [ABSTRACT FROM AUTHOR]

Background: Sports levels, baseline patient-reported outcome measures (PROMs), and surgical procedures are correlated with the outcomes of anterior cruciate ligament reconstruction (ACLR). Machine learning may be superior to conventional statistical methods in making repeatable and accurate predictions. Purpose: To identify the best-performing machine learning models for predicting the objective and subjective clinical outcomes of ACLR and to determine the most important predictors. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 432 patients who underwent anatomic double-bundle ACLR with hamstring tendon autograft between January 2010 and February 2019 were included in the machine learning analysis. A total of 15 predictive variables and 6 outcome variables were selected to validate the logistic regression, Gaussian naïve Bayes machine, random forest, Extreme Gradient Boosting (XGBoost), isotonically calibrated XGBoost, and sigmoid calibrated XGBoost models. For each clinical outcome, the best-performing model was determined using the area under the receiver operating characteristic curve (AUC), whereas the importance and direction of each predictive variable were demonstrated in a Shapley Additive Explanations summary plot. Results: The AUC and accuracy of the best-performing model, respectively, were 0.944 (excellent) and 98.6% for graft failure; 0.920 (excellent) and 91.4% for residual laxity; 0.930 (excellent) and 91.0% for failure to achieve the minimal clinically important difference (MCID) of the Lysholm score; 0.942 (excellent) and 95.1% for failure to achieve the MCID of the International Knee Documentation Committee (IKDC) score; 0.773 (fair) and 70.5% for return to preinjury sports; and 0.777 (fair) and 69.2% for return to pivoting sports. Medial meniscal resection, participation in competitive sports, and steep posterior tibial slope were top predictors of graft failure, whereas high-grade preoperative knee laxity, long follow-up period, and participation in competitive sports were top predictors of residual laxity. High preoperative Lysholm and IKDC scores were highly predictive of not achieving the MCIDs of PROMs. Young age, male sex, high preoperative IKDC score, and large graft diameter were important predictors of return to preinjury or pivoting sports. Conclusion: Machine learning analysis can provide reliable predictions for the objective and subjective clinical outcomes (graft failure, residual laxity, PROMs, and return to sports) of ACLR. Patient-specific evaluation and decision making are recommended before and after surgery. [ABSTRACT FROM AUTHOR]

Purpose: To identify the radiological predictive risk factors for anterior cruciate ligament reconstruction (ACLR) failure, compare the diagnostic accuracies of different parameters of conventional radiographs and magnetic resonance imaging (MRI), and determine the cutoff values for patients at higher risk.Methods: Twenty-eight patients who were diagnosed as ACLR failure via MRI or arthroscopic examination were included in the study group. They were matched to 56 patients who underwent primary ACLR with the same surgical technique and without graft failure at the minimum 24-month follow-up by age, sex, and body mass index. On true lateral whole-leg radiographs, the posterior tibial slope (PTS) referenced to the tibial mechanical axis (PTS-mechanical), PTS referenced to the tibial proximal anatomical axis (PTS-anatomical), and anterior tibial translation (ATT) were measured. On the sagittal slices of MRI, the medial tibial slope (MTS), medial tibial plateau (MTP) subluxation (MTPsublx), lateral tibial slope (LTS), and lateral tibial plateau (LTP) subluxation (LTPsublx) were obtained. Receiver operator characteristic (ROC) curves were constructed to compare the diagnostic performance and determine the cutoff values of different radiological parameters.Results: The study group demonstrated higher values of PTS-mechanical (10.7° ± 2.9° vs 8.7° ± 1.9°, p = 0.003), PTS-anatomical (13.2° ± 2.8° vs 10.5° ± 2.5°, p < 0.001), ATT (10.7 ± 3.3 mm vs 8.9 ± 2.2 mm, p = 0.014), LTS (9.4° ± 2.1° vs 5.5° ± 2.5°, p < 0.001), and LTPsublx (8.2 ± 2.8 mm vs 6.8 ± 1.9 mm, p = 0.009) as compared with the control group. The area under the ROC curve of LTS was significantly larger than that of PTS-mechanical (p = 0.006) and PTS-anatomical (p = 0.020). Based on the maximum Youden indexes, the cutoff values of PTS-mechanical, PTS-anatomical, and LTS were 10.1° (sensitivity, 64.3%; specificity, 78.6%), 12.0° (sensitivity, 71.4%; specificity, 71.4%), and 7.7° (sensitivity, 85.7%; specificity, 80.4%), respectively.Conclusion: Due to the morphological asymmetry of the MTP and LTP, steep LTS measured on MRI is the best radiological predictor of ACLR failure. Detailed measurement of the LTS on MRI is recommended to evaluate the risk of ACLR failure prior to the surgery.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

• Developed Semi-analytic Monte Carlo Method for solid rocket plume polarized radiation. • Simulated solid rocket plume polarized characteristics. • The effects of different light sources on the polarized characteristics of the plume were analyzed. Polarization optical detection has been widely used in the detection and identification of particle containing media such as clouds, aerosols, fire plumes, and volcanic smoke. Solid rocket plume is a typical high-temperature gas–solid two-phase medium. Polarization optical detection of solid rocket plume has attracted much attention in recent years. The polarized radiation transfer mechanism of solid rocket plume is complex, especially in the infrared band, with both the scattering radiation transfer from external incident light and the scattering radiation transfer from the high-temperature region inside the jet flame to the outside. The research on the polarization scattering characteristics of solid jet flame still needs to be further developed. Therefore, this study focuses on modeling the infrared polarization scattering mechanism and the simulation of polarization transfer characteristics of a solid rocket gas–solid two-phase plume, which can guide the usability analysis of solid rocket plume polarization detection. A novel model based on Semi-analytic Monte Carlo Method is proposed to simulate polarized radiation transfer of solid rocket plume. The wavelength and angle dependence of the self-radiation polarization characteristic of a solid rocket plume is simulated based on the proposed model. Note that the overall polarization degree of the plume shows wavelength selectivity and angle sensitivity at different wavelengths. The spatial distribution of polarization degree at 1.55 μm, 2.2 μm, and 2.75 μm shows that the plume edge's polarization degree is higher than the plume center. The findings suggest that the ratios of the relative contribution of self-radiation, direct solar radiation, and background polarization radiation components to the total polarization characteristics are 0.47 %, 70.50 %, 29.03 % at 1.55 μm and 20.43 %, 79.55 %, 0.02 % at 2.75 μm. [ABSTRACT FROM AUTHOR]

• It was found that the agricultural land expanded significantly, desert reduced from 1993 to 2019 in the oasis region in Hotan River Basin, China. • The key indicators of the coupling system of vegetation–climate, soil-adjusted vegetation index, albedo, surface temperature, and evapotranspiration were calculated and mapped their spatial-temporal dynamics. • We investigated how the different landscape patterns altered the interaction between vegetation and climate in the desert oasis ecosystem and quantified the effects with structural equation model. In the arid region, the oasis is characterized by a desert substance and a mosaic of vegetation. The biophysical processes and interactions between vegetation and the local climate in this kind of region are determined by the macroscopic structure of the ecosystems, i.e. landscape patterns. To understand how these landscape patterns impact regional hydro-heat coupling across space and evolve over time, we utilized remote sensing observational data and methods to examine the relationships among these factors. In this case, we focused on the oasis along the upstream of the Hotan River Basin in the Taklamakan Desert in Xinjiang of western China and employed the satellite imagery datasets of Landsat from 1993 to 2019 to investigate the dynamics of vegetation–climate factors. Based on the land use and cover change datasets, the landscape pattern metrics, including patch density (PD), contagion index (CONTAG), fractal dimension (FRAC), were calculated to measure the landscape features on the different aspects, i.e. the fragmentation, the connectivity, and the complexity. With the algorithm of land surface energy balance, the land surface indicators, including the soil-adjusted vegetation index (SAV I), albedo, surface irradiance temperature (T s), and evapotranspiration (ET), were calculated to represent the key process in the interaction of vegetation–climate. The temporal-spatial dynamics of the landscape patterns and the vegetation–climate metrics were mapped and demonstrated in a quantitative manner. The statistical results revealed that during the past decades, the agricultural land in the study area had significantly increased by 17 %. Grassland and shrubs had also expanded, while the desert area decreased from 82.57 % to 78.82 % of the total area, with an overall reduction rate of 1.4 %/10a. It was found the study area was getting warmer and dryer based on the general trends of T s and ET observed during the period of 1993–2019. The agricultural land had the highest PD and CONTAG , and the lowest FRAC. The agricultural land had the lowest T s and the highest ET. The results of structural equation model identified the decoupling effects of PD and CONTAG on the regional hydro-heat environment, while confirmed that FRAC had positive impact on the coupling between T s and ET. Our study bridged the landscape pattern with the regional vegetation–climate interaction and provided the suggestions for the landscape planning and management for a more sustainable arid region. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Anterolateral structure augmentation (ALSA) has been applied to prevent residual rotatory instability and lower clinical failure rates after anterior cruciate ligament (ACL) reconstruction (ACLR); however, the effect of combined ALSA on the maturity of ACL grafts remains unknown. Purpose: To evaluate the graft maturity and patient–reported outcomes in patients who underwent double–bundle ACLR with or without ALSA. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 92 patients who underwent double–bundle ACLR between January 2016 and July 2019 were included in the present study—44 patients with isolated ACLR (ACLR group) and 48 patients with combined ACLR and ALSA (ALSA group). Demographic characteristics, intraoperative findings, and patient–reported outcomes were prospectively collected. On postoperative magnetic resonance imaging at the 2–year follow–up, the signal–to–noise quotient (SNQ) values were separately calculated for 6 sections of the ACL graft, including the femoral intratunnel graft (FTG), intra–articular graft (IAG), and tibial intratunnel graft (TTG) of the anteromedial bundle (AMB) and the posterolateral bundle (PLB). Superior graft maturity was usually indicated by lower SNQ values. Results: The rates of return to preinjury sports were 47.9% and 27.3% in the ALSA and ACLR groups, respectively (difference, 20.6% [95% CI, 1.3%-40%]; P =.042). The AMB demonstrated significantly lower SNQ values in the ALSA group than in the ACLR group (FTG, 7.04 ± 3.65 vs 9.44 ± 4.51 [ P =.006]; IAG, 6.62 ± 4.19 vs 8.77 ± 5.92 [ P =.046]; TTG, 6.93 ± 3.82 vs 8.75 ± 4.55 [ P =.040]). The SNQ values were significantly lower in the ALSA group for 2 of the 3 sections of the PLB (IAG, 7.73 ± 4.61 vs 9.88 ± 5.61 [ P =.047]; TTG, 5.88 ± 3.10 vs 8.57 ± 4.32 [ P =.001]). Partial lateral meniscectomy was correlated with higher SNQ values of the TTG in the AMB (β = 0.27; P =.009) and the PLB (β = 0.25; P =.008), with both groups pooled. Higher body mass index, smaller ACL graft–Blumensaat line angles, larger AMB graft diameters, and lower postoperative Tegner scores were also associated with inferior maturity in specific regions of the ACL graft. Conclusion: A combination of ACLR and ALSA is a desirable option to improve the maturity of ACL grafts for patients who are young or expected to return to pivoting sports. Meanwhile, further investigations with higher levels of evidence and longer periods of follow–up are warranted. [ABSTRACT FROM AUTHOR]

The structure and function of aquatic communities in reservoir ecosystems can be strongly affected by dam construction. The Ecopath model is an effective tool that reveals the food web structure and pathways of energy flows. In this study, it was applied to analyze the trophic interactions and energy flows within the Manwan reservoir ecosystem on Lancang River in southwest China. Ecotrophic efficiency (EE) was calculated and the value ofEEwas 0.073 for the least-exploited piscivorous fishes (top predators) and 0.93 for the most-exploited zoobenthos. Four estimated trophic levels of the groups varied from 1 for detritus and phytoplankton (level I) to 3.69 for piscivorous fishes (level IV) and the remaining groups were mainly at trophic levels II and III. Food web structures and interactions were well represented by a linear food chain that was dominated by a detritus pathway; that is, energy flows from detritus were as important as phytoplankton in the web. The proportion of total energy flow originating from detritus was 46% while the other 54% came from primary producers. The average transfer efficiencies between trophic levels were 16.6% from primary producer and 15.7% from detritus. Total system throughput was found to be 5550 t km−2yr−1, total primary production/total respiration ratio was 2.46, and the ascendency index was 27.4%. These results showed that Manwan reservoir ecosystem was an immature ecosystem and still at its development stage. These results are helpful for biodiversity preservation and the understanding and monitoring of reservoir ecosystems which are key resources for fish and other aquatic organisms. [ABSTRACT FROM AUTHOR]

Connectivity of habitat patches is crucial for wildlife dispersal and survival, and identifying patches with high importance for maintaining connectivity can aid effective wildlife management. Knowledge of the habitat distribution of the Tibetan antelope in the Altun Mountain National Nature Reserve, which is essential for connectivity analysis, remains limited. We analyzed potential habitat distribution and priority patches using GIS-based habitat suitability modeling with three weighting factors and evaluated the connectivity of habitat patches under four dispersal distance scenarios. Patches with high habitat suitability covered 25.39 % of the total area, and these patches were selected for connectivity analysis as resource patches. Connectivity analysis indicated that, although the overall probability of connectivity (PC) showed an upward trend with increasing dispersal distance, the importance of each patch varied considerably under different dispersal distance scenarios. Transfer analysis of patch numbers between different importance levels revealed that the number of patches becoming less important was higher than the number of patches becoming more important when dispersal distance increased. In addition, nine patches covering 38.49 % of the suitable habitat area were identified as priority patches, in particular the patches near the Kardun and the Karchuka inspection stations. We also found that the habitat distribution of the Tibetan antelope obtained from the suitability model matched the population distribution determined by a field survey. Correlation analysis between patch area and the percentage of PC index value loss (dPC) revealed that the larger patches in this region were more likely to be important for maintaining connectivity. [ABSTRACT FROM AUTHOR]

Background: Exosomes derived from mesenchymal stromal cells (MSCs) reportedly enhance the healing process. However, no studies have investigated the effect of exosomes from infrapatellar fat pad (IPFP) MSCs on tendon-bone healing and intra-articular graft remodeling after anterior cruciate ligament reconstruction (ACLR). Purpose: To evaluate the in vivo effect of exosomes from IPFP MSCs on tendon-bone healing and intra-articular graft remodeling in a rat model of ACLR. Study Design: Controlled laboratory study. Methods: A total of 90 skeletally mature male Sprague Dawley rats underwent unilateral ACLR using an autograft. All rats were randomly divided into 3 groups: sham injection (SI) group (n = 30), control injection (CI) group (n = 30), and IPFP MSC–derived exosome injection (IMEI) group (n = 30). At 2, 4, and 8 weeks postoperatively, tendon-bone healing and intra-articular graft remodeling were evaluated via biomechanical testing, micro–computed tomography, and histological analysis; macrophage polarization was evaluated using immunohistochemical staining. Results: Biomechanical testing demonstrated a significantly higher failure load and stiffness in the IMEI group than in the SI and CI groups at 4 and 8 weeks postoperatively. Moreover, a thinner graft-to-bone healing interface with more fibrocartilage was observed in the IMEI group at both time points. Micro–computed tomography revealed greater new bone ingrowth in the IMEI group than in the other groups, as demonstrated by smaller mean bone tunnel areas and a larger bone volume/total volume ratio. Additionally, more cellular infiltration was observed in the intra-articular graft in the IMEI group than in the other groups at 4 weeks, followed by more regularly organized fibers with mature collagen at 8 weeks. Notably, similar trends of macrophage polarization were found at both the graft-to-bone interface and the intra-articular graft in the IMEI group, with significantly fewer proinflammatory M1 macrophages and larger numbers of reparative M2 macrophages than in the SI and CI groups. Conclusion: IPFP MSC–derived exosomes accelerated tendon-bone healing and intra-articular graft remodeling after ACLR, which may have resulted from the immunomodulation of macrophage polarization. Clinical Relevance: The IPFP can be easily harvested by most orthopaedic surgeons. Exosomes from IPFP MSCs, constituting a newly emerging cell-free approach, may represent a treatment option for improving tendon-bone healing and intra-articular graft remodeling after ACLR. [ABSTRACT FROM AUTHOR]

• Rapid calculation of atmospheric molecular absorption characteristics in the frequency range of 0.3-30THz. • A fitting coefficient table of exponential kernel is established to rapidly calculate the absorption coefficient • The relative contribution of absorptive capacity of eight atmospheric molecules compared to H 2 O molecules was studied. This paper focuses on rapidly calculating atmospheric molecular absorption properties in the 0.3–30 THz frequency range of terahertz waves. It conducts research related to spectral radiation models and fast computation model databases. Based on the latest version of the High-resolution transmission molecular absorption database-2020, in conjunction with the line-by-line (LBL) spectral radiative calculation method, the spectral absorption characteristics of nine atmospheric molecules (H 2 O, CO 2 , O 3 , NO, N 2 O, NO 2 , NH 3 , SO 2 , CH 4) are analyzed. The relative contributions of the eight other gas molecules absorption abilities in the terahertz range are examined, with H 2 O molecule serving as the reference. Taking into account the non-gray absorption properties of atmospheric molecules and the need for fast computation, this study divides the frequency range of 0.3–30 THz into 24 calculation bands based on the spectral absorption distribution characteristics of atmospheric molecules. Utilizing LBL calculations with a resolution of 0.01 cm−1, a non-correlated wideband K-distribution model (WBK) is developed, which achieves nearly the same computational accuracy as LBL. Furthermore, the WBK radiation calculation model is validated under both uniform and non-uniform atmospheric conditions based on earth atmospheric environmental parameters. An exponential kernel fitting coefficient table for the rapid calculation of atmospheric molecular absorption coefficients is established based on the WBK radiation calculation model to improve computational efficiency further. This database enables fast calculation of 24 broadband absorption coefficients (corresponding to 7 Gaussian integration points) within 0–100 km altitude in earth atmosphere. [ABSTRACT FROM AUTHOR]

A swirl micro-combustor for premixed hydrogen/air flames is proposed to improve flame stability. The swirl micro-combustor consists of a cylindrical combustion chamber and an inlet section where a swirler with 6 straight vanes at an angle of 45° is placed in an annular inlet duct. The flame stabilization mechanism and combustion characteristics at different velocities, equivalence ratios, and solid materials are analyzed using three–dimensional numerical simulations. The results indicate that the role of the inner recirculation zone on flame anchoring is dominating while the corner recirculation zone is favorable to the preheating effect. The coupling of the heat recirculation from the solid walls and the recirculating flow in the recirculation zones contributes to the improvement of flame stability. Increasing inlet velocity weakens the preheating effect. The flame temperature, combustion intensity, and preheating energy increase with an increasing equivalence ratio. The preheating effect is enhanced by using highly thermally conductive materials, thereby facilitating the initiation of the chain reactions. • A novel swirl micro-combustor is proposed to improve flame stability. • Inner recirculation zone dominates in flame anchoring. • Outer recirculation zone is favorable to preheating effect. • The coupling of heat recirculation and recirculating flow contributes to the improvement of flame stability. • Effects of inlet velocity, equivalence ratio, and solid material are analyzed. [ABSTRACT FROM AUTHOR]

• Interaction between nitrogen deposition and climate warming was insignificant. • Nitrogen deposition enhanced leaf visible absorption and near-infrared reflection. • Climate warming weakened leaf visible and near-infrared light reflection. Temperature and nitrogen (N) are limited factors on the Qinghai-Tibetan Plateau (QTP). Climate change and increasing N deposition on the QTP have posed threats to the sustainability of alpine ecosystems. To examine plant spectral responses to N deposition and climate change, we measured leaf spectral reflectance of Poa crymophila, a common forage species grown in alpine meadow (AM) and alpine steppe (AS) on the eastern QTP under four N addition treatments (CK, 8, 40, 72 kg N ha −1 yr −1). We used natural climate gradients from colder and drier AS to warmer and wetter AM to simulate the climate change on the QTP. Results showed that both N deposition and climate change had significant effects on entire visible and near-infrared regions (p < 0.05), but the interactive effects were insignificant (p > 0.05). Enhanced visible absorption, increased near-infrared reflection, a red shift for red edge and a blue shift for green peak were observed with increasing N addition levels. The modified red edge simple ratio index and photochemical reflective index increased gradually in response to N addition (p < 0.05). These responses indicated that N deposition may make leaf wider and thicker, increase leaf chlorophyll content and photochemical efficiency, and enhance photosynthetic capacity. Climate warming and wetting had opposite effects from N deposition on leaf reflectance of Poa crymophila. These observations showed the potential to monitor the status of Poa crymophila under future climate change and N deposition with leaf spectral measurements. [ABSTRACT FROM AUTHOR]

Quantifying drought variations at multi-time scales is important to assess the potential impacts of climate change on terrestrial ecosystems, especially vulnerable desert grassland. Based on the normalized difference vegetation index (NDVI) and standardized precipitation evapotranspiration index (SPEI), we assessed the influences of different time-scales drought (SPEI-3, SPEI-6, SPEI-12, SPEI-24, and SPEI-48 with 3, 6, 12, 24, and 48 months, respectively) on vegetation dynamics in the Qaidam River Basin, Qinghai-Tibet Plateau. Results showed that (1) temporally, annual and summer NDVI increased, while spring and autumn NDVI decreased from 1998 to 2015. Annual, spring, and summer SPEI increased, and autumn SPEI decreased. (2) Spatially, annual, spring, summer, and autumn NDVI increased in the periphery of the Basin, with 45.98%, 22.68%, 43.90%, and 30.80% of the study area, respectively. SPEI showed a reverse variation pattern with NDVI, with an obvious decreasing trend from southeast to northwest. (3) Annual vegetation growth in most areas (69.53%, 77.33%, 86.36%, 90.19%, and 85.44%) was correlated with drought at all time-scales during 1998–2015. However, high spatial and seasonal differences occurred among different time-scales, with the maximum influence in summer under SPEI24. (4) From month to annual scales, NDVI of all land cover types showed higher correlation to long-term drought of SPEI24 or SPEI48. Vegetation condition index (VCI) and SPEI were positively correlated at all time-scales and had a more obvious response in summer. The highest correlation was VCI of grassland (June–July) or forest (April–May, August–October) and SPEI48. This study contributes to exploring the effect of drought on vegetation dynamics at different time scales, further providing credible guidance for regional water resources management. [ABSTRACT FROM AUTHOR]

The grassland soils of the Qinghai-Tibet Plateau (QTP) store a large amount of organic carbon because of the cold, humid climate, and topsoil organic carbon is quite sensitive to global climate changes. However, the spatio-temporal dynamics and factors that influence the soil organic carbon (SOC) on the QTP's grassland are not understood well. Moreover, there are few comparative analyses of different approaches to estimate the QTP' SOC. In this study, we estimated the storage and patterns of SOC density (SOCD) using several methods, including MODIS (moderate-resolution imaging spectroradiometer) retrieval, field data and previous empirical models (Models1-4, and soil organic matter (SOM)). And their relations with aboveground biomass, soil moisture, temperature, elevation, and soil conductivity were further explored. The results showed that SOC showed a similar variation trend in the different models, in which it decreased with increasing bulk density (BD) in the topsoil at 30 cm. For meadow and steppe grasslands, Models 1, 2, and 4 showed similar estimated values of SOCD, while Model3 had a lower value than them. SOC storage in the BD 3 and SOM methods had abnormal values, while the MODIS-NDVI, BD 1, 2, and 4 methods had similar SOC stock values for meadow and steppe grassland. Moreover, meadow grassland had a higher SOC storage than did steppe grassland, with means values of 397.9×1010 kg and 242.2×1010 kg, respectively. SOCD's spatial distribution using MODIS-NDVI method differed clearly from the empirical models, with a significant tendency for spatial variation that increased from the northwestern to southeastern regions on the QTP. Therefore, based on the values estimated and spatial variation features, the MODIS-NDVI method may be a more feasible and valid model to estimate SOC. Moreover, the mean annual SOCD values during 2000–2015 showed an increasing trend, with a higher mean value in meadow and a lower mean value in steppe. Further, SOCD was correlated significantly and positively with aboveground biomass and soil moisture, and negatively correlated with elevation and soil conductivity. Increasing temperature had negative effects on SOCD, which was consistent with the global trend. These results indicated that topsoil moisture plays a key role in SOCD spatial patterns. Our results provide valuable support for the long-term estimation of SOCD in future research on the QTP. [ABSTRACT FROM AUTHOR]

• TRI is modeled and analyzed in a swirling furnace under oxycombustion conditions. • Contribution of radiation to total heat flux on the wall is more than 45%. • A local increase of 18% in radiative heat flux is caused by TRI. • High O 2 concentration highlights the significance of TRI. • Increasing swirl number weakens the TRI effect. With the application of oxyfuel combustion technology, the status of radiative heat transfer in oxyfuel flames is prominent, and accurate description of it is essential. This study simulates the turbulence radiation interaction (TRI) in a swirling gas-fired furnace to understand the thermal radiation behavior under oxycombustion conditions. Employing the non-gray weighted sum of gray gases model calculates the radiative properties of the participating media and the TRI is modeled. The effects of TRI on the radiative heat transfer in the furnace under different oxycombustion conditions and swirl numbers are analyzed. The results show that the effects of thermal radiation on temperature fields are critical in the gas-fired furnace, especially for oxycombustion condition with high oxygen concentration, and the same is true for TRI effect. With the increase of O 2 concentration in O 2 /CO 2 oxidizer, the radiative heat flux on the chamber wall, the radiative heat flux contribution to total heat flux, and the net radiative heat loss are increased. Increasing swirl number can weaken the TRI effect. It is observed that with 35% O 2 in oxidizer, the radiation contribution to heat flux along the entire wall and local increase of radiative heat flux due to TRI effect are almost than 45% and 18%, respectively. [ABSTRACT FROM AUTHOR]

• The temporal stability of community biomass decreases with the time series. • The temporal stability of forb biomass increased with the time series. • Community asynchrony determined the temporal stability of plant community biomass. • Annual maximum and minimum temperature regulated the temporal stability of forb. Climate changes can affect the temporal stability of plant community biomass on the Qinghai-Tibet Plateau, but most studies were based on short-term field climate manipulation experiments. However, the response of biomass stability of natural alpine meadow remains largely unexplored. We conducted a 20-year experimental study monitoring aboveground biomass of plant functional groups (grass, forb and sedge) and community in eastern QTP, with linear regressions and a path analysis of: annual temperature, annual night minimum temperature, annual daytime maximum temperature, annual precipitation, annual daytime precipitation, annual night precipitation, biomass stability of grass, biomass stability of forb, plant functional groups asynchrony to assess the influence climate change and biological factors on the temporal stability of plant community biomass. We found that it was plant functional groups asynchrony rather than climate change that determined the temporal stability of plant community biomass. Our findings suggest that future climate change has a considerable uncertainty in the temporal stability of the plant community biomass in the alpine meadow and we should combine with both field climate manipulation experiments and long-term observational experiments to assess the influence of climate change on the temporal stability of plant community. [ABSTRACT FROM AUTHOR]

Ecosystem service (ES) supply and demand are affected by changes in land use and the supply of specific ecosystem services for human consumption, respectively. Future spatio-temporal dynamics and their coupling relations with land use in China have not been well analysed. In this study, based on future land use scenarios of Li's database, ES supply, demand and balance (supply minus demand) were revealed utilizing land use and land cover (LULC) matrix model in China in 2010, 2050 and 2100. The results showed that ES supply, demand and balance had great spatial and temporal variations under different scenarios at national and provincial scales. Higher population and higher urban expansion scenarios will lead to a significant decreasing in the balance values of different categories and total ESs in most provinces. The ecological sensitivity index was calculated to indicate the impact of land use intensity on ecosystem services. The results showed that the sensitivity levels in approximately 90% of provinces were low for all the scenarios, as only Anhui, Zhejiang, Jiangxi and Liaoning in 2050 and Gansu in 2100 were extremely sensitive to changes in supply, while only provinces in the central-eastern regions were sensitive with obvious differences from the demand. The coupling coordination analysis between land use intensity and ES balance was applied to identify the provinces with low-level coordination in land use and ES management. The results showed that the coordination change in most provinces remained stable under four scenarios. However, some provinces displayed an improving trend from low to moderate coordination or from moderate to high coordination and a degrading trend from moderate to low coordination or from high to moderate coordination from 2010 to 2100. This study contributes to exploring the effect of land use on ecosystem service evolution, thereby providing credible guidance for future land and ES management. Unlabelled Image • Ecosystem services had significant spatio-temporal differences under four scenarios. • The sensitivity levels in approximately 90% of provinces in China were low for four scenarios. • The coupling coordination degree change in most provinces remained stable from 2010 to 2100. • Measures should be taken to improve the coupling coordination degree in some degrading provinces. [ABSTRACT FROM AUTHOR]

• We monitored the dynamics of seedling recruitment of 303 grassland species. • Seed size indirectly and positively affected seedling survival via biomass growth. • The direct effect of seed size on seedling survival was negative. • This study has a reference for breeding of new herbage varieties on Tibetan plateau. Theoretical models of life-history strategies assume a positive relationship between seed size and subsequent offspring survival (seed size–survival relationship). There is limited empirical evidence, however, on how this relationship changes across environments or in relationship to seedling traits. Moreover, characterizing the dynamics of seedling recruitment under natural conditions is central to understanding how seedling recruitment may in turn affect large-scale ecological processes. Here, first-year seedling survival was monitored from emergence for 303 angiosperms species originated from alpine and sub-alpine meadows of the eastern Tibetan Plateau grasslands, across an experimental light gradient consisting of four treatments. We used linear models (LM) and phylogenetic generalized linear models (PGLM) to test for the seed size–survival relationship, and how this relationship differed across light treatments. We also used path analysis (PA) and phylogenetic confirmatory path analysis (PPA) to assess how seed size interacted with other seedling traits (seedling emergence time, specific leaf area, root: shoot biomass ratio, and biomass growth) to either directly or indirectly affect seedling survival. We found seed size to be positively associated with seedling survival only under low to medium light treatments only in LM (not in PGLM). PA and PPA revealed that the positive effect of seed size on seedling survival was indirect, mainly acting via biomass growth. Under low light, larger seeds exhibited greater biomass growth, which in turn increased seedling survival. In contrast, the direct effect of seed size on seedling survival is negative. In sum, the seed size–survival relationship appears to be both environmentally and phylogenetically dependent. The survival advantage of large seeds appears to be the result of their ability of higher biomass growth after emergence in low resource environments. However, our results also suggest there may be an underlying trade-off with larger seeds facing a lesser, but direct risk of increased mortality. The influence of environment on seedling traits, the interaction among traits, and phylogeny should be taking into consideration when modeling the dynamics of seedling recruitment. [ABSTRACT FROM AUTHOR]

The authors offer a response to comments made by G. S. Bullocks and colleagues on their study about developing applicable machine learning (LM) models and determining important predictors for the outcomes of anterior cruciate ligament (ACL) reconstruction (ACLR). Topics include different models that were introduced as previously reported and validated by Ramkumar et al, issues that have been mentioned by Bullocks and colleagues that have been observed and discussed.

Highlights • An evaluation system considering pressure and pressure-bearing was established. • Grid scale ecological security was evaluated using this system and entropy method. • County scale security level was evaluated based on entropy matter-element model. • Changes of ecological security situation between 2000 and 2015 were explored. Abstract Ecological security is important for social and economic sustainable development which needs stable resources and eco-environment support. In this study, we established an evaluation indicator system considering pressure and pressure-bearing to quantify the ecological security for Kunming city as it is a socioeconomic center in Southwest China with important ecological niche and rapid urbanization. According to the weights assigned by entropy method, we overlaid 13 indicators which were divided into 2 units, pressure indicators and pressure-bearing indicators, to evaluate the ecological security on grid scale. And then, ecological security level on district-county scale was evaluated based on the entropy matter-element model. On this basis, we explored their spatial distribution characteristics and the change trend from 2000 to 2015. Results showed that spatial distribution characteristic of ecological security evaluation was similar with the results of pressure evaluation, showing the scores and levels gradually increased from the urban area to the surrounding areas. Compared the ecological security levels in 2000 and in 2015, both of the highest value and the lowest value increased slightly. In general, the area with improved ecological security situation accounted for 89.10% of the total area. In terms of the change trend of ecological security levels, eight counties deteriorated while five counties remained unchanged which were driven by different deterioration reasons. The evaluation results of this study can provide comprehensive and targeted support for regional sustainable development. [ABSTRACT FROM AUTHOR]

• Plume infrared signatures were studied from the phenomenological point of view. • A methodology to characterize the rocket altitude from several spectral bands was proposed. • Effects of afterburning on the radiation phenomena were studied. • Effects of atmospheric attenuation and observation angles were discussed. Rocket exhaust plume treated as a significant radiation source has been widely used in space-based detection. In this paper, infrared radiation signatures of plumes were studied in the view of the phenomenon. The reacting plume flows were calculated by an axisymmetric computational fluid dynamics (CFD) solver. Radiative properties of gases were evaluated with the statistical narrow-band (SNB) model by relying on the NASA-3080 database. The line-of-sight (LOS) based on the single-line-group (SLG) approximation was employed for radiative transfer computations. The numerical model was validated against reference data. Based on this model, radiation characteristics of Atlas-II liquid rocket plumes were computed and analyzed in aspects of afterburning, atmospheric attenuation, spectral bands and observation angle. Results show that afterburning has a significant improvement in the wavelengths of 1.5–6.0 μm. Also, the atmospheric attenuation greatly decreases the plume radiance at low altitudes but it can be ignored above 40 km. Radiance is strongly dependent on the spectral bands. The altitude-varying spectral dependency can contribute to the rocket altitude estimation. The effect of the observation angle on the radiance distributions is varying with the spectra band and the flight altitude. These results are helpful for the design of the rocket motors and the application of the infrared detecting system. [ABSTRACT FROM AUTHOR]

Highlights • Infrared thermal radiation noise of the bow-shock layer was investigated. • A relationship between the radiation intensity and flight conditions was given. • Simulations results were discussed including the LOS, station and direction. • Effects of the dome radius and altitudes on the radiation noise were studied. Abstract To examine the effect of atmospheric trace species on the infrared thermal radiation of a supersonic dome, a series of radiation characteristics with different geometry sizes at near-ground altitudes were investigated numerically. The conjugate heat transfer method was applied to build the heat transfer model of the optical dome. Three major radiating species of H 2 O, CO 2 , and CO were taken into account in the shock layer. A line-by-line (LBL) method was used for evaluating the radiative properties of species. A line-of-sight (LOS) approach was applied to solve the radiative transfer equation (RTE). The simulated and measured results of the dome were also proposed to validate the numerical method. The effects of the dome geometry size, the dome material and the time-varying altitude on the infrared radiation noise were studied in detail. The results show that the altitude-varying radiation intensity along the LOS is related to the ambient density and velocity. The variation of the dome radius is proportional to the total radiation received on the dome surface. It is observed that the maximum radiation intensity along the LOS does not occur in the normal direction of the receiving point, but it is determined by both the flow field parameters and the path length. Also, the radiation increment corresponding to different dome sizes approximately obeys a Gaussian distribution related to the product of density and velocity. [ABSTRACT FROM AUTHOR]

Abstract In this study, a novel elliptical jet-stabilized combustor is developed; the combustion and emission characteristics are numerically investigated and compared with those of a circular jet-stabilized combustor. Five elliptical combustors with different semi-major/semi-minor axis ratios (1.00, 1.27, 1.56, 1.89, and 2.25) are considered, and an optimization method for adjustable stabilizer jet air supply is proposed. An Eulerian-Lagrangian approach is used for solving the liquid fuel spray. Employing the realizable k - ε turbulence model and the finite-rate/eddy-dissipation model simulates the turbulent combustion. The discrete ordinate method is used to model thermal radiation, and the thermal and prompt NO formations are to be predictive of NO emissions. The numerical models are validated against available experimental data. The results show that the semi-major/semi-minor axis ratio significantly affects the performance of elliptical jet-stabilized combustors. To improve the temperature uniformity and to reduce NO emissions, the proposed optimization method is successfully applied. Compared with the circular combustor, the optimized elliptical combustor achieves strong mixing performance, resulting in improved combustion and emission performance. By adjusting the major/minor axis jet mass flow rate ratio (m a / m b = 0.6) in the elliptical combustor with semi-major/semi-minor axis ratio of 1.56, NO emissions are reduced by 50% compared with the circular combustor. Graphical abstract Image 1 Highlights • A novel elliptical jet-stabilized combustor is designed and compared with a circular one. • The effect of semi-major/semi-minor axis ratio is investigated. • The optimization of adjustable stabilizer jet air supply is carried out. • NO emissions reduce in elliptical jet-stabilized combustors. [ABSTRACT FROM AUTHOR]

Abstract The continuously increasing concentration of atmospheric CO 2 has considerably altered ecosystem functioning. However, few studies have examined the long-term (i.e. over a decade) effect of elevated CO 2 on soil microbial communities. Using 16S rRNA gene amplicons and a GeoChip microarray, we investigated soil microbial communities from a Californian annual grassland after 14 years of experimentally elevated CO 2 (275 ppm higher than ambient). Both taxonomic and functional gene compositions of the soil microbial community were modified by elevated CO 2. There was decrease in relative abundance for taxa with higher ribosomal RNA operon (rrn) copy number under elevated CO 2 , which is a functional trait that responds positively to resource availability in culture. In contrast, taxa with lower rrn copy number were increased by elevated CO 2. As a consequence, the abundance-weighted average rrn copy number of significantly changed OTUs declined from 2.27 at ambient CO 2 to 2.01 at elevated CO 2. The nitrogen (N) fixation gene nifH and the ammonium-oxidizing gene amoA significantly decreased under elevated CO 2 by 12.6% and 6.1%, respectively. Concomitantly, nitrifying enzyme activity decreased by 48.3% under elevated CO 2 , albeit this change was not significant. There was also a substantial but insignificant decrease in available soil N, with both nitrate (NO 3 −) (−27.4%) and ammonium (NH 4 +) (−15.4%) declining. Further, a large number of microbial genes related to carbon (C) degradation were also affected by elevated CO 2 , whereas those related to C fixation remained largely unchanged. The overall changes in microbial communities and soil N pools induced by long-term elevated CO 2 suggest constrained microbial N decomposition, thereby slowing the potential maximum growth rate of the microbial community. Graphical abstract Unlabelled Image Highlights • Effects of 14 years of experimentally elevated CO 2 on soil microbes in a semi-arid grassland were examined. • The abundance-weighted average rrn copy number of significantly changed OTUs declined by elevated CO 2. • The nitrogen fixation gene nifH and the ammonium-oxidizing gene amoA significantly decreased by elevated CO 2. • Elevated CO 2 constrained microbial N decomposition, thereby slowing potential maximum growth rate of microbial community. [ABSTRACT FROM AUTHOR]

Abstract Spatially quantifying ecosystem services (ES) supply, demand and balance dynamics and exploring their relations with socio-economic factors are very significant for regional sustainability. In this study, land use/land cover (LULC) matrix model was used to quantify the relevant capacity of the ES supply, demand and balance in China. Also, we explored the spatial-temporal characteristics of ES at three scales (national, provincial and city scale). The results revealed that the ES supply, demand and balance in China had strong spatial heterogeneity and showed different time-varying characteristics on different scales. For the provinces with ES deficit, linear optimization model was then applied to achieve the theoretical ES balance through land cover conversion. For the provinces with negative regulating ES, farmland should be significantly reduced while desert and grassland should be converted to farmland and forest for the provinces with negative provisioning ES. In addition, the key driving factors of ES dynamics were selected through ordination analysis of 109 cities at city scale. The results showed that forest proportion was the most important influencing factor of ecosystem services supply while ES supply management can be carried out by adjusting the output values of agriculture, forestry and animal husbandry. On the other hand, ES demand can be adjusted by per capita GDP, energy consumption per unit of GDP and permanent population. The results can provide targeted information with ES management and this method can be applied at a smaller scale considering data availability. This study provides a convenient and propagable method for ES quantification and a quantitative support for regional ES management decisions. Graphical abstract Unlabelled Image Highlights • ES had strong spatiotemporal heterogeneity on national, provincial and city scales. • Forest proportion was the most important driving force of ES supply. • Different land cover conversion strategies should be implemented for ES balance. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • FQI is a suitable index for evaluating the vegetation restoration. • Cu content had the greatest promotional effect on FQI. • Cd and TK contents had a significantly inhibitory effect on FQI. • Excessive nutrients might produce 'toxicity' to the growth of vegetation. Abstract Open-pit mining activities cause great damage to the local ecosystems. It is therefore necessary to assess and recover the vegetation status to maintain ecological stability. In this study, the Floristic Quality Index (FQI) was used to assess the vegetation habitat and the structural equation model (SEM) was applied to quantify the influences of different environmental factors on FQI in the Kunyang open-pit phosphate rock mine in Yunnan Province, China. Non-metric multidimensional scaling analyses revealed that great differences of vegetation community composition existed in the sampled plots, even those at similar distances to mining areas, which indicates that disturbing distance was not the only factor to determine the vegetation community. SEM results showed that Cu promoted the FQI most obviously (0.84), followed by Co (0.75), while the inhibition of Cd content in soil to the FQI was the most significant (−0.88), followed by TK (−0.82), and C (−0.79). Soil fertility quality and soil pollution indexes were also established to analyze the effects of comprehensive soil parameters on FQI. The results showed that the soil fertility quality index had a strong negative effect on FQI, which revealed that higher levels of TP, TN, TK, and other nutrients in the soil would produce 'toxicity' to the growth of vegetation. Findings from our study could provide a scientific method for assessing the ecological restoration results in the mining area. [ABSTRACT FROM AUTHOR]

In this paper, we propose an idea of using asymmetric dielectric resonators to increase the number of perfect absorption bands. We break the symmetry of the dielectric resonators by reducing the length of one of the two silicon split strips. A quad-band MPA is achieved in the near-infrared band based on the asymmetric-dielectric–dielectric–metal (ASDDM) structure, which can excite two extra electric quadrupole (EQ) modes comparing with the symmetry structure exciting only two dipole modes. Operated as a refractive index sensor, those four narrow absorption bands have the figure of merit (FOM) as high as 338.6, 98.5, 38, and 60.6, respectively. This preliminary analysis shows that the resonators asymmetric method is feasible for designing multiple-band MPAs. To obtain more absorption bands, we propose another idea of stacking the dielectric resonators on metal resonators other than only stacking metal resonators. A single-band MPA is first designed based on the metal–dielectric–metal (MDM) structure. Next, we stack the asymmetric dielectric resonators of the quad-band MPA on the metal resonators of the single-band MPA. The absorption spectrum shows that five perfect absorption bands are achieved in the near-infrared band, which preliminary proves the feasibility of the modified resonators stacked method for designing multiple-band MPAs. [ABSTRACT FROM AUTHOR]

• The working medium studied is supercritical liquid hydrogen. • Different from the traditional circular U-tube structure, this paper adopts the triangular U-tube structure for research. • Five different structural types of U-tubes were compared and the one with the best heat transfer performance was selected. • This work provides a useful technical guidance for thermal design and thermal management of neutron source and target station, as well as novel ideas for flow and heat transfer of supercritical liquid hydrogen in U-tube. In this study, the heat transfer characteristics of supercritical hydrogen in triangular U-tubes with different radius were investigated. In order to compare the heat transfer capacity of triangular U-tubes, and to explore the heat transfer characteristics of supercritical liquid hydrogen inside them, a three-dimensional numerical simulation was carried out by Fluent. The unstructured grid and RNG k-ε turbulence model were used to encrypt the grid. Meanwhile, the grid independence and the effectiveness of the turbulence model are verified. The T w , T f and Nu along the triangular U-tube at different q and Re were compared. The result shows that T w , T f and Nu increase with the increase of q and Re. The change of Re was found to be largest for Nu. The effect of secondary flow on Nu was similar to the entrance effect of upstream straight pipe, and the effect of secondary flow on Nu was slightly larger than the entrance effect. This work provides a useful technical guidance for thermal design and thermal management of neutron source and target station, as well as novel ideas for flow and heat transfer of supercritical liquid hydrogen in U-tube. [ABSTRACT FROM AUTHOR]

Partitioning, a method considering environmental protection and development potential, is an effective way to provide regional management strategies to maintain ecological sustainability. In this study, we provide a large-scale regional division approach and present a strategy for Southwest China, which also has extremely high development potential because of the “Western development” policy. Based on the superposition of 15 factors, including species diversity, pattern restriction, agricultural potential, accessibility, urbanization potential, and topographical limitations, the environmental value and development benefit in the region were quantified spatially by weighting the sum of indicators within environmental and development categories. By comparing the scores with their respective median values, the study area was divided into four different strategy zones: Conserve zones (34.94%), Construction zones (32.95%), Conflict zones (16.96%), and Low-tension zones (15.16%). The Conflict zones in which environmental value and development benefit were both higher than the respective medians were separated further into the following 5 levels: Extreme conflict (36.20%), Serious conflict (28.07%), Moderate conflict (12.28%), Minor conflict (6.55%), and Slight conflict (16.91%). We found that 9.04% of nature reserves were in Conflict zones, and thus should be given more attention. This study provides a simple and feasible method for regional partitioning, as well as comprehensive support that weighs both the environmental value and development benefit for China's current Ecological Red Line and space planning and for regional management in similar situations. [ABSTRACT FROM AUTHOR]

Integrating biodiversity and ecosystem services (BES) has been viewed as an appropriate approach to identifying conservation priorities. Taking Xishuangbanna tropical region in Southwest China, different BESs (habitat quality [used as a proxy for biodiversity], carbon storage, and water yield) were quantified using the InVEST model and conservation hotspots from 1976, 1990, and 2010 were identified by overlapping and ranking the service layers. Results showed that BESs areas were unevenly distributed. High habitat quality and carbon storage areas located in the eastern part of the region were mainly occupied by broad-leaved forest, while high water yield areas were covered by grassland and tropical forests. Recognized hotspots were primarily composed of the broad-leaved forest and shrub grassland. However, these habitat types declined by nearly 50% from 1.25×105 ha to 0.63×105 ha and became more fragmented during the study period. We also found that the sub-watersheds which decreased in BES had fewer hotspots distributed and suffered greater landscape fragmentation. Our study further explored the impacts of land-use conversion on BES, and illustrated the necessity and feasibility of BESs in identifying potential conservation areas. [ABSTRACT FROM AUTHOR]

Rapid plantation expansion and its associated impacts on habitat fragmentation and landscape connectivity in many tropical areas has raised increasing concerns as to its impact on Ecosystem Services (ES). Using the InVEST modelling suite, we evaluated critical ES dynamics in four zones of varying plantation expansion intensity (high, medium, low and no plantation expansion) in Xishuangbanna prefecture in Southwest China from 1976 to 2012. Based on these results, we also exmained the relationship between ES and landscape pattern and connectivity derived by the “probability of connectivity” model. We found that during the study period, plantation area increased more than 20 times in Xishuangbanna prefecture as a whole, while broad-leaved forest cover decreased by nearly 30%. The impact of plantation on ES was substantial at both the regional and local scale. Carbon stocks and water yield services decreased by 15.48% and 10.85%, respectively, from 1976 to 2012 throughout the region as a whole. Within the selected study zones, carbon stock and water yeild decreased by 45% and 32%, respectively, from the no plantation to the high plantation zones in 2012 specifically. Plantation expansion has also resulted in a decrease in natural forest cover and a high level of habitat fragmentation. Landscape connectivity decreased by a range of 54.64–95.58% throughout the study area, with 134.58 km 2 of forest patches of high importance reduced to medium or low importance during the study period. Correlation analysis showed that carbon storage was more closely correlated to landscape connectivity than forest habitat percentage, large patch index or cohesion index. Together, these results highlight that habitat configuration with a high connectivity level between fragmented patches is important for maintaining critical Ecosystem Services. [ABSTRACT FROM AUTHOR]

Appropriate graft length within the joint and inside the osseous tunnel is essential for achieving posterior stability and adequate anchorage strength. Because of the curving path and thickness of the graft in double-bundle posterior cruciate ligament (PCL) reconstruction, especially in double-bundle PCL augmentation (with remnant preservation), the actual intra-articular length of PCL grafts, which remains unknown, may be longer than previously published values. The main purpose of the current study is to measure the actual intra-articular graft length required in sandwich-style PCL reconstruction (remnant-preserving double-bundle PCL augmentation) and Zhao-style non-remnant-preserving double-bundle PCL reconstruction (semi-anatomic double-bundle PCL reconstruction using double-double tunnel with tibial medial and lateral arrangement). Nine matched pairs of intact cadaveric knees were randomized between two groups and respectively received sandwich-style PCL reconstruction (remnant-preserving group) and Zhao-style non-remnant-preserving double-bundle PCL reconstruction (non-remnant-preserving group). The tunnel positions were exactly the same in two groups. The anterolateral (AL) bundle was reconstructed with four-stranded semitendinosus tendon, and the posteromedial (PM) bundle was reconstructed with four-stranded gracilis tendon. For each bundle, the length of the graft portion within the joint was measured. The current study indicated that in remnant-preserving group, the average intra-articular exposed portion was 42.0 mm (SD, 1.3 mm; range, 40.0 mm to 43.4 mm) for the AL bundle and 32.5 mm (SD, 2.9 mm; range, 27.8 mm to 35.8 mm) for the PM bundle. In non-remnant-preserving group, the intra-articular exposed portion was 34.5 mm (SD, 1.0 mm; range, 32.7 mm to 36.0 mm) for the AL bundle and 29.1 mm (SD, 2.1 mm; range, 25.2 mm to 31.9 mm) for the PM bundle. For both the AL and PM bundles, significant differences were found in average intra-articular graft length between the two groups. The current study, whose methodology is more rigorous and accurate by measuring the actual intra-articular graft length, has direct applications to clinical practice. When considering the total graft lengths during reconstruction, it is necessary to recognize that remnant PCL has a space occupation effect on graft and that remnant preservation requires longer intra-articular graft lengths than non-remnant preservation. [ABSTRACT FROM AUTHOR]

SOM is a crucial factor that indicates soil fertility and vegetation status and, to a considerable extent, influences the CO 2 concentration in the atmosphere and even the global carbon cycle. We collected 294 SOM data from the secondary soil survey of Yunnan province in 1979 and investigated 210 soil sample sites (0–20 cm depth) in 2011 to enhance the understanding of the spatial variability of SOM between two phase data and its dominant influencing factors in the mountainous region in southwestern China. We examined whether land use types (farmland, grassland, forestland and scrubland), topographic conditions (elevation, slope and CTI) and vegetation coverage (NDVI) affect the spatial distribution and content of SOM in a mountainous region in southwestern China. The results indicated that, SOM content decreased among different land use types in the following order: forestland > scrubland > grassland > farmland. An accurate spatial prediction of SOM content has great significance in the estimation of the SOC pool. This study exhibited that the combined use of vegetation index and terrain attributes would result in a suitable method of predicting SOM distribution even in complex terrain. The prediction of spatial variability in SOM contents was achieved establishing IDW and UK. The root mean square error RMSE and ME methods were selected as comparison criteria to indicate prediction accuracy. Owing to the heterogeneous natural environment, the application of the UK and IDW methods is limited. And it is still challenging that further work was necessary to accurately predict spatial distribution of SOM by choosing appropriate methods in these mountain areas. This study laid a foundation to estimate and evaluate SOM sequestration for regional land use management. [ABSTRACT FROM AUTHOR]