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The accumulation and transfer of carcinogens, including polycyclic aromatic hydrocarbons (PAHs), in the human body, especially from mother to fetus, has been the subject of many research studies, but the related data are limited and the mechanisms are unknown. This is the first study to investigate the distribution of PAHs in paired samples of maternal blood, placenta tissue, and umbilical cord blood in relation to pregnancy complications. Sixty-four pairs of samples were collected in Kunming, China; 18 were from healthy pregnant women and 46 were from patients with pregnancy complications. The predominant PAHs in these pregnant women were high-molecular-weight (HMW) compounds, mainly from the incomplete combustion or pyrolysis of biomass. In the control group, the total amount of HMW compounds (Σ HMW PAHs) was significantly higher in maternal blood than in umbilical cord blood, which suggested that placenta may decrease PAH transfer in healthy pregnant women. However, this phenomenon was not observed for low-molecular-weight PAHs or in the case group. In the control group, Σ 16 PAH and Σ HMW PAH in the placenta were higher than those in maternal blood and umbilical cord blood; for the case group, a contrasting result was observed. Σ HMW PAHs in the placenta was significantly higher in the control group than in the case group. The same results were observed after the exclusion of the impact of the genotypes of the PAH metabolic enzymes (both phase I and phase II enzymes). Thus, the decreased PAH transfer from mother to fetus may partially result from the accumulation of PAHs inside the placenta. [ABSTRACT FROM AUTHOR]

Hand-tungsten inert gas welding is employed using Inconel 82 as a filler metal to weld T92 ferritic steel and HR3C austenitic steel. The microstructures of the joints are analyzed via optical and transmission electron microscopy. The corrosion resistance of the joints is evaluated via electrochemical and immersion corrosion tests, whereas the corrosion products and passive films are analyzed using scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that the weld metal region of the T92/HR3C dissimilar metal joint formed a dense passivation film containing Cr2O3 and NiO owing to the highest Cr and Ni contents, which effectively prevented the entry of chloride ions into the matrix, thus impeding corrosion and providing optimal corrosion resistance. Compared to the base material of T92, the heat-affected zone of T92 shows fine austenite grains and subgrain structures, as well as a relatively thick Cr2O3 passivation film, which improved the corrosion resistance. [ABSTRACT FROM AUTHOR]

Ticagrelor produces a more potent antiplatelet effect than clopidogrel and inhibits cellular uptake of adenosine, which is associated with several cardiovascular consequences. We aimed to explore the correlation between adenosine and cyclic adenosine monophosphate ( cAMP) plasma concentration and antiplatelet effect by clopidogrel or ticagrelor in patients with acute coronary syndrome ( ACS) receiving dual antiplatelet therapy ( DAPT). We conducted a prospective, observational and single-centre cohort study enrolling 68 patients with non- ST-segment elevation ACS from January 2016 to May 2016. We monitored the inhibition of platelet aggregation ( IPA) and assessed adenosine, adenosine deaminase ( ADA) and cAMP plasma concentrations by immunoassay on admission and 48 hr after coronary angiography. The demographic and clinical data were collected by reviewing their medical records. The two groups exhibited similar baseline characteristics including adenosine, ADA and cAMP. The mean IPA in patients receiving ticagrelor was significantly higher than that in patients receiving clopidogrel (93.5% versus 67.2%; p = 0.000). Also, we observed that patients treated with ticagrelor had a significantly higher increase in levels of adenosine and cAMP compared with those treated with clopidogrel (1.04 (0.86; 1.41) versus 0.04 (−0.25; 0.26); p = 0.029 and 0.78 (−1.67; 1.81) versus 0.60 (−1.91; 4.60); p = 0.037, respectively). And there was a weak correlation between IPA and adenosine as well as cAMP plasma concentration ( r = 0.390, p = 0.001 and r = 0.335, p = 0.005, respectively). Ticagrelor increased adenosine and cAMP plasma concentration compared with clopidogrel in patients with ACS. [ABSTRACT FROM AUTHOR]

The T92/HR3C dissimilar metal weld joints were fabricated by manual tungsten inert gas (TIG) welding with Inconel 82 as the filler metal. After fatigue tests at 640 °C, it was found that the location of the fatigue fracture shifted from the weld metal (WM) to the heat-affected zone of the T92 steel (T92-HAZ) with a decrease in stress amplitudes (171–189 MPa to 155–166.5 MPa). The fatigue crack propagation behavior of the two fracture modes mentioned above was monitored by an in-situ scanning electron microscopy (SEM) imaging test. In addition, the results of the transmission electron microscopy (TEM) analysis showed that under high-stress amplitudes, the initiation of cracks at the weld metal was caused by the interaction between dislocations with Nb(C,N) in the matrix and M 23 C 6 on the grain boundary. At long-term high temperature, the carbides precipitated in the weld metal played a role in strengthening the grain boundaries, so the matrix structure still maintained high strength and stability. However, the dislocation movement in the T92-HAZ accelerated the transformation of lath martensite into equiaxed subgrains, and the coarsening and aggregation of Cr-rich M 23 C 6 carbides resulted in the initiation of cracks in this region. Therefore, as the stress amplitude decreased, the fatigue fracture location of the DMWJs shifted from the weld metal to T92-HAZ. • In-situ experiment provided a better understanding on high temperature fatigue behavior of complex microstructure. • Fatigue work showing the transition of failure location from weld metal to HAZ as the stress amplitude decreases. • Effects of the coarsened carbides and dislocations on the fatigue failure of the dissimilar weld joint were studied. [ABSTRACT FROM AUTHOR]

Thermo-gravimetric analysis (TGA) was used to assess the thermal stability of a temporary adhesive. High temperature is one important factor leading to the voids formation in bonded wafers, which can degrade bonding force and cause chipping. Some heat treatment experiments were devised to investigate the influence of high temperature on the bonding quality. The prebake process before temporary bonding plays a very important role in preventing voids from forming between bonded wafers, which can be confirmed by the TGA results. A short loop evaluation was performed to assess the temporary bonding quality with different prebake and heat treatment temperatures. The results were used to optimize prebake conditions. Application to 2.5D through silicon vias temporary bonding and backside processing is demonstrated. [ABSTRACT FROM AUTHOR]

Horizontal wells can significantly improve the gas production and are expected to be an efficient exploitation method for the industrialization of natural gas hydrates (NGHs) in the future. However, the near-wellbore hydrate is highly prone to decomposition during the drilling process, owing to the disturbance aroused by the factors such as the drilling fluid temperature, pressure, and salinity. These issues can result in the engineering accidents such as bit sticking and wellbore instability, which are required for further investigations. This paper studies the characteristics of drilling fluid invasion into the marine NGH reservoir with varied drilling fluid parameters via numerical simulation. The effects of the drilling fluid parameters on the decomposition behavior of near-wellbore hydrates are presented. The simulating results show that the adjustments of drilling fluid density within the mud safety window have limited effects on the NGH decomposition, meanwhile the hydrates reservoir is most sensitive to the drilling fluid temperature variation. If the drilling fluid temperature grows considerably due to improper control, the range of the hydrates decomposition around the horizontal well tends to expand, which then aggravates wellbore instability. When the drilling fluid salinity varies in the range of 3.5–7.5%, the increase in the ion concentration speeds up the hydrate decomposition, which is adverse to maintaining wellbore stability. [ABSTRACT FROM AUTHOR]

Although metallic stents are effective in preventing acute occlusion and reducing late restenosis after coronary angioplasty, many concerns still remain. In this report, short-term effects of fully bioabsorbable sirolimus-loaded poly- l-lactic acid (PLLA) stents (Xinsorb) were evaluated in a porcine coronary model. Commercially available PLLA-coated sirolimus-eluting stents (Excel) were used as controls. The purpose of this study was to assess technical feasibility, biocompatibility, and impact on coronary stenosis of fully bioabsorbable PLLA stents. Our preliminary experience suggested that Xinsorb stents have succeeded in preventing elastic recoil and suppressing neointimal formation for the first 90 days and only mildly delayed the endothelialisation process of the stented blood vessel. Coronary stenosis following Xinsorb and Excel stent implantations after 30 and 90 days was 18.6 ± 5.2% versus 21.4 ± 7.2% and 24.5 ± 4.7% versus 27.7 ± 5.6%, respectively ( p > 0.05). Both Xinsorb and Excel stents required approximately 1-3 months for re-endothelialization of the inner wall of stented blood vessels. These data provided additional insights into the mechanism and efficacy of fully bioabsorbable PLLA stents in normal porcine coronary arteries while raising questions regarding the potential durability of this novel medical device. Long-term follow-up will be required to validate the long-term efficacy of fully bioabsorbable PLLA stents. [ABSTRACT FROM AUTHOR]

Abstract: Soil nitrogen (N) mineralization is an important component of the N cycling process in ecosystems. In this study, we assessed the seasonal patterns of net soil N mineralization and nitrification using an intact soil core incubation method in the upper 0–10cm soil layer in three representative land use types. These included a fenced steppe, an abandoned field and a crop field in a grassland landscape of Inner Mongolia, China. The study was conducted from September 2004 to August 2005. Our results demonstrate marked seasonal variations in inorganic N pools, net nitrogen mineralization and net nitrification. Net N mineralization was higher in the crop field than in the fenced steppe and the abandoned field. Daily rates of N mineralization and nitrification during the growing season were approximately twice their corresponding mean annual rates. Accumulative mineralization and nitrification of N during the growing season accounted for about 90 and 85% of that measured for the entire year. Rates of mineralization and nitrification were positively correlated with soil bulk density, but negatively correlated with soil pH. Net N mineralization and nitrification were strongly regulated by land use, precipitation, soil water and temperature. [Copyright &y& Elsevier]

Green-leaved foliage plants are valued for their leaf forms and sizes but mainly for their foliar greenness. Evaluation of the quality of these plants has been based primarily on visual grading, which often brings biases, depending on the appraisers. The objective of this study was to evaluate the possibility of using the SPAD-502 as an instrument for estimating plant quality. Ten green-leaved foliage plant species were grown in shaded greenhouses and treated with either a water-soluble fertilizer or a controlled-release fertilizer, each at four nitrogen (N) rates. Six months later, mature leaf thickness was measured and visual quality graded. After the greenness of the mature leaves was measured with the SPAD-502 meter, leaf chlorophyll was extracted using dimethyl sulphoxide, and chlorophyll content was determined. Results showed that leaf thickness ranged from 0.19–0.66 mm among the 10 species but had no apparent effect on either SPAD readings or chlorophyll content. Visual-quality grades of the plants were closely correlated with the SPAD readings ( r ≥ 0.84). Highly significant linear relationships ( r 2 ≥ 0.87) were found between SPAD readings and chlorophyll a , b , or total chlorophyll content. Thus, the SPAD-502 could be used as an instrument to provide quick, nondestructive, and objective estimation of quality for green-leaved foliage plants. [ABSTRACT FROM AUTHOR]

Timely and nondestructive detection of leaf nitrogen (N) status could greatly improve nutrient management practices for greenhouse ornamental production. This study evaluated the feasibility of using a SPAD-502 chlorophyll meter for estimating leaf chlorophyll and nitrogen contents of the peace lily (Spathiphyllum Schott). Three cultivars 'Claudia', 'Double Take', and 'Petite' were grown in a soilless substrate and sub-irrigated with solutions containing N at 50, 100, 200 or 400 mg L-1 through an ebb-and-flow system. The SPAD-502 chlorophyll meter was used to measure leaf greenness. Chlorophyll contents of leaves were also analyzed using the dimethyl sulphoxide extraction method. Total N was determined by a CNS Auto-Analyzer. Correlation analyses showed that coefficients (r2) between SPAD values and leaf chlorophyll contents were 0.83, 0.77, and 0.73 for 'Claudia', 'Double Take', and 'Petite', respectively, and coefficients (r2) between SPAD values and leaf N contents of 'Claudia', 'Double Take', and 'Petite' were 0.84, 0.82, and 0.91, respectively. These results suggest that the readings from a SPAD meter can be used for rapidly and nondestructively estimating leaf chlorophyll and N status of the peace lily. As high quality Spathiphyllum were produced at the N concentration of 200 mgL-1, the corresponding SPAD values established in this study could facilitate in situ decision-making on N application for the production of the peace lily. [ABSTRACT FROM AUTHOR]

CD47‐SIRPα axis is an immunotherapeutic target in tumor therapy. However, current monoclonal antibody targeting CD47‐SIRPα axis is associated with on‐target off‐tumor and antigen sink effects, which significantly limit its potential clinical application. Herein, a biomimetic nano‐degrader is developed to inhibit CD47‐SIRPα axis in a site‐specific manner through SIRPα degradation, and its efficacy in acute myocardial infarction (AMI) is evaluated. The nano‐degrader is constructed by hybridizing liposome with red blood cell (RBC) membrane (RLP), which mimics the CD47 density of senescent RBCs and possesses a natural high‐affinity binding capability to SIRPα on macrophages without signaling capacity. RLP would bind with SIRPα and induce its lysosomal degradation through receptor‐mediated endocytosis. To enhance its tissue specificity, Ly6G antibody conjugation (aRLP) is applied, enabling its attachment to neutrophils and accumulation within inflammatory sites. In the myocardial infarction model, aRLP accumulated in the infarcted myocardium blocks CD47‐SIRPα axis and subsequently promoted the efferocytosis of apoptotic cardiomyocytes by macrophage, improved heart repair. This nano‐degrader efficiently degraded SIRPα in lysosomes, providing a new strategy for immunotherapy with great clinical transformation potential. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen (N) deposition, generally, has been simulated through a single or relatively few N applications per year for its ecological effect study. Despite the importance of timing in ecosystem processes, ecological experiments with more realistic N addition frequencies are rare.We employed a novel design with typical twice (2X) versus atypical monthly (12X) N applications per year to explore effects of N addition frequency on above‐ and below‐ground biodiversity and function.Each year, several response variables from either below‐ground or above‐ground growth, N status and cycling, or plant and bacterial diversity differed as a result of N addition frequency. BNPP showed a large frequency effect in the relatively moist year but not in the dry year. Nitrogen addition decreased root growth in the monthly relative to the biannual applications, which could be highly consequential for predicting changes in global carbon and nitrogen cycling. Simulated N deposition tended to perturb biodiversity, but it is noteworthy that 12X applications that spread N deposition more evenly through a year have much less negative impacts on plant and bacterial diversities than 2X amendments per year. Soil N mineralization rate in year 6 was much lower when N additions were monthly compared with a biannual amendment, especially when simulated N deposition was high.We have established that amendment frequency matters for understanding ecosystem response to N deposition. Experiments that more closely mimic the anthropogenic process of N deposition are needed to best assess ecosystem and potential global biogeochemical changes. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Acute coronary syndrome (ACS) has become a vital disease with high mortality worldwide. A combined antiplatelet therapy (aspirin and a P2Y12 antagonist) is commonly used to prevent re‐infarction in ACS patients who have undergone percutaneous coronary intervention (PCI). Clopidogrel, a P2Y12 antagonist, plays an important role in the inhibition of platelet aggregation (IPA). However, it is a pro‐drug requiring biotransformation by cytochrome P450 (CYP450). The aim of this study is to unravel the effect of clopidogrel‐associated genetic variants on inhibition of platelet activity and clinical outcomes in ACS patients. In our study, a total of 196 patients with metabolic gene polymorphism of clopidogrel were enrolled, and their antiplatelet effect as well as their cardiovascular events were collected. Approximately 2 mL of venous blood samples were used for genotype detection and another 4 mL were collected for platelet reactivity with thrombelastography. The primary clinical end‐point was defined as a combination of cardiovascular mortality and revascularization for targeted vascular lesion. Based on the results of IPA, the prevalence of high on‐treatment platelet reactivity (HPR) was 17.3% and the majority of patients (82.7%) obtained normal on‐treatment platelet reactivity (NPR). The HPR group had significantly higher body mass index (BMI) and lower arachidonic acid (AA) induced IPA (P < 0.05). Therapy including Glycoprotein (GP) IIb/IIIa antagonist increased IPA (P < 0.05). ADP‐induced IPA effect was lower with the presence of CYP2C19*2, *3 and paraoxonase (PON)1 Q192R loss‐of‐function (LOF) alleles, respectively (P < 0.05). Multivariate logistic regression analysis demonstrated that aspirin resistance (AA‐induced IPA < 50%) had a greater risk of the occurrence of major adverse cardiovascular events (MACE) (OR = 3.817; 95% CI: 1.672‐8.700; P = 0.002). CYP2C19*2 LOF alleles were associated with high risk of MACE in 1‐year post PCI operations (OR = 2.571; 95% CI: 1.143‐5.780; P = 0.030). For the ACS patients, the presence of CYP2C19*2 and PON1 Q192R LOF alleles were the major drivers of HPR. [ABSTRACT FROM AUTHOR]

To solve the problem that uneven illumination is inevitably to reduce the image quality, an adaptive illumination correction algorithm based on a combined model of bottom-hat and improved gamma transform is proposed to process and improve the image quality. In this paper, the multi-scale Gaussian function is adopted to estimate the image illumination components. Then, the two-dimensional gamma function is improved, and the coefficients of gamma transform are dynamically adjusted by using the obtained illumination components to realize the adaptive correction of the image. Finally, the corrected image is fused with the image transformed by the bottom-hat. Through a large number of experiments, it is verified that the proposed method can retain more detailed information, and the corrected picture does not produce small noise points with a better fidelity effect. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to clarify the efficacy of early goal-directed renal replacement therapy (GDRRT) for treatment of cardiorenal syndrome (CRS) patients after acute decompensated heart failure (ADHF). Methods: In the retrospective, observational study, we enrolled 54 patients in the early GDRRT group and 63 patients in the late GDRRT group. Baseline characteristics, clinical data at initiation renal replacement therapy time, and the clinical outcome were collected and several parameters were compared and analyzed between 2 groups. Results: The urine volume at GDRRT initiation time in the early group was higher than that in the late GDRRT group (1,060.3 ± 332.1 vs. 300.5 ± 148.3 mL, p < 0.001). Hemodynamic parameters such as mean artery pressure were higher (70.06 ± 32.99 vs. 54.34 ± 40.88 mm Hg, p = 0.012), the heart rate was slower (80.17 ± 15.26 vs. 99.21 ± 25.45 bpm, p = 0.002), and the diameter of inferior vena cava was narrower (22.00 ± 1.91 vs. 25.77 ± 5.5 mm, p = 0.04) in early GDRRT. Primary end point was inhospital all-cause mortality and cardiovascular mortality, which was obviously lower in the early GDRRT group (respectively 24.1 vs. 60.3%, p = 0.002 and 20.3 vs. 50.8%, p = 0.005). The second end point of kidney recovery in the early GDRRT group was much better than that in the latter GDRRT group (p = 0.018). Moreover, urine volume after GDRRT of the early group was more significant than that of the late group (1,432 ± 172 vs. 702 ± 183 mL, p = 0.005). Conclusion: This study clarified the effectiveness of the early GDRRT strategy in ADHF patients suffered from CRS, which reduced inhospital mortality and improved the urine output and clinical kidney recovery outcome. [ABSTRACT FROM AUTHOR]

Shale inhibitor is an additive for drilling fluids that can be used to inhibit shale hydration expansion and dispersion, and prevent wellbore collapse. Small molecular quaternary ammonium salt can enter the interlayer of clay crystal, and enables an excellent shale inhibition performance. In this paper, a novel ionic shale inhibitor, triethylammonium acetate (TEYA), was obtained by solvent-free synthesis by using acetic acid and triethylamine as raw materials. The final product was identified as the target product by Fourier transform infrared spectroscopy (FT-IR). The inhibition performance of TEYA was studied by the mud ball immersion test, linear expansion test, rolling recovery test and particle size distribution test. The results demonstrated that the shale inhibitor shows a good shale hydration inhibition performance. The inhibition mechanism was studied by FT-IR and X-ray diffraction (XRD), respectively; the results showed that triethylammonium acetate TEYA could enter the crystal layer of clay and inhibit it through physical adsorption. [ABSTRACT FROM AUTHOR]

Understanding the biodiversity–productivity relationship and underlying mechanisms in natural ecosystems under realistic diversity loss scenarios remains a major challenge for ecologists despite its importance for predicting impacts of rapid loss of biodiversity worldwide. Here we report the results of a plant functional group (PFG) removal experiment conducted on the Mongolian Plateau, the largest remaining natural grassland in the world.Our results demonstrated that the biodiversity–productivity relationship varied among positive linear, neutral and unimodal forms under different PFG loss patterns. Moreover, the form of this relationship with the same PFG loss pattern sometimes changed through time.The abundance of the remaining PFG(s) before removal and their compensation following the loss of other PFGs were two major mechanisms affecting the biodiversity–productivity relationship under diversity loss scenarios. The abundance effect promoted positive responses of productivity to biodiversity, but the compensation effect caused several biodiversity–productivity relationships, hinging on its direction (positive or negative) and strength. As indicated by the values of the compensation index, negative, zero and partial compensations contributed to the positive relationships, while full compensation resulted in a neutral relationship. Overcompensation at intermediate PFG richness levels created a unimodal curve in our system, but it could also lead to a negative linear relationship.Synthesis. Our experiment provides a vivid picture of how the form of the biodiversity–productivity relationship varies among different diversity loss patterns in a natural ecosystem. We argue that compensation by the remaining species, which is not revealed by synthesized biodiversity experiments, plays a critical role in shaping the form of this relationship when diversity is lost from existing systems. The direction and strength of compensation are highly dependent on extirpation scenarios. Thus, impacts of biodiversity loss on natural ecosystems are likely more complex than predicted by the canonical positive saturating curve obtained from the synthesized biodiversity experiments. We suggest that models forecasting the consequences of biodiversity declines on natural ecosystems should take into account diversity loss patterns and the ensuing compensation. [ABSTRACT FROM AUTHOR]

Inspired by shallow-water sloshing in a moving tank, a novel type of vibration-based piezoelectric energy harvesting device composed of a piezoelectric bimorph beam and an extension tank is proposed in this paper. The structure and working principle of the proposed device are provided. Then, the effects of different heights of water filling in the tank on the performances of the harvester are studied and analyzed. Experiments are set up to investigate the actual device performance by changing the base excitation frequency and load resistance for different water heights. The results show that by modulating the water height, the resonant frequency and bandwidth can be adjusted, which can enhance the energy harvesting performance of the device at different ambient vibration frequencies. This study provides some clues to improve the performance of the vibration-based energy harvesting devices. [ABSTRACT FROM AUTHOR]

Service composition can quickly build new value-added composite services by combining existing Web services. However, with the complex and changeable Internet environment, composite services need to effectively understand and manage requirements in a flexible and adaptive manner, and also be able to quickly and proactively provide high-quality services through a series of dynamic evolution models. In response to these challenges, in this study, we propose a service composition evolution method that can adaptively select the appropriate service to improve user satisfaction and service quality. First, we introduce a deep clustering method based on the topic model and auto-encoder, which considers the function description documents and parameter information of the services to reduce the search space of the candidate services. Furthermore, we describe a requirement-oriented context-sensitive task model to integrate functional and non-functional user requirements by connecting the context of Web subtasks. Then, we present a dynamic service matching method with QoS threshold judgement to filter and rank the services. We applied the proposed evolution method to the datasets of real-world Web services and measured the performance using standard measurement metrics. The prototype implementation and results of simulation experiments verified the effectiveness of each part of our method. • A novel service composition evolution method is proposed. • A deep clustering method is presented to implement the service clustering process. • RCT model and various evolutionary types are used to satisfy user requirements. • Simulation experiments on prototype system show the effectiveness. [ABSTRACT FROM AUTHOR]

• The influence of clay minerals on hydrate formation is revealed. • The bound water on the clay surface is not involved in the formation of hydrates. • The hydrolysis of interlayer cations on the montmorillonite surface inhibits the formation of hydrates. Clay is widely present in hydrate reservoirs and drilling and completion fluids. A quantitative understanding of hydrate growth characteristics on clay solid phase surfaces is vital for predicting hydrate formation and preventing secondary hydrate generation in solid-phase-containing drilling fluid systems. The experiments and nonequilibrium molecular dynamics simulations are performed to investigate the characteristics of methane hydrate growth on the surfaces of kaolinite and montmorillonite. The experiments and dynamics simulated results demonstrate that a large number of bound waters is absorbed on the clay surface. However, the bound water does not participate in hydrate formation. The mechanisms by which clay minerals influence the formation of hydrates are different. Kaolinite reduces the induction time of hydrate formation, but the massive amount of bound water on the kaolinite surface reduces the total amount of free water molecules, which hinders the formation of hydrates, and the inhibition effect on hydrates is more significant than that with montmorillonite. Significantly, the hydrolysis of interlayer cations on the montmorillonite surface inhibits the formation of hydrates. This study will help us to understand the mechanism for gas hydrates formation on reservoir clay minerals, and to predict the amount of hydrate reservoir reserves, which will further aid hydrate resource drilling and exploration. [ABSTRACT FROM AUTHOR]

Thermostatically controlled loads (TCLs) are viewed as a promising demand-side resource for smoothing out the intermittency of renewable energy. However, it is difficult to dispatch these dispersed flexibility resources to serve the microgrid without establishing the aggregation model of TCLs. Motivated by this need, this paper presents a distributed and real-time economic dispatch strategy based on the alternating direction multiplier method, that allows TCLs and distributed generations to work in coordination to maintain the power balance of islanded microgrids under fluctuating renewable energy sources, while considering the occupant comfort and the fair utilization. A semi-online parameter identification method that does not involve occupant privacy is proposed for obtaining parameters of inverter-based TCLs. This method is based on recursive least squares and designed with a changing forgetting factor to avoid data saturation. Also, a virtual battery model considering parameter heterogeneity is established for TCLs, and the scheduling capability of the TCLs cluster under different ambient temperatures is determined using deep neural networks. Besides, this paper introduces a fast distributed consensus algorithm without changing the communication structure to improve the convergence speed of the distributed algorithm. The effectiveness of the proposed strategy is validated on an islanded microgrid with 100 TCLs. • Estimating parameters of TCLs by a non-invasive method to protect privacy. • Evaluating the dispatch capability by a deep neural network. • Distributed ADMM solves the real-time EDP of microgrids in parallel. • Guiding TCLs to participate in power scheduling with a consistent utilization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Intercellular VE-Cadherin maintanence and intracellular ROS scavenging are critical in endothelial barrier preservation. • Platelet membrane fused liposome facilitates targeted delivery. • Locally activated thrombin triggers extracellular release of ANGPTL4. • Neutral endothelial cytoplasm is suitable for Fe 3 O 4 to scavenge ROS. • Extracellular and intracellular drugs release are combined for enhanced endothelial barrier preservation. Following myocardial ischemia–reperfusion (MI/R), the endothelial barrier is heavily damaged. This is partially due to the accumulation of intracellular reactive oxygen species (ROS) in endothelial cells, leading to disruptive intercellular VE-Cadherin junctions and endothelial cells apoptosis. Systemic administration of drugs is limited by poor delivery and release at pathological sites, resulting in compromised therapeutic effect. Herein, by exploiting the inherent nature of platelets migrating to injured endothelium and local activation of thrombin, we fabricated functional platesomes (Fe@PLP-TR-A) to co-deliver angiopoietin-like 4 (ANGPTL4) and ROS scavenger Fe 3 O 4 to injured endothelium in heart affected by MI/R. Thanks to the capability for multidrug loading and easy-modification feature of platesomes, we conjugated ANGPTL4 on the surface of platesomes with a thrombin responsive peptide and encapsulated Fe 3 O 4 in the inner space. After systemic injection, Fe@PLP-TR-A successfully arrived at the endothelial cells at injured endothelium due to the platelet-mimetic adhesion effect of platesomes which was fabricated by fusing platelet membranes and lipid membranes. Following the cleavage of thrombin-responsive peptide, which was activated by injured endothelium, ANGPTL4 was released extracellularly and bound to the receptor on endothelial cells to prevent the disruption of VE-Cadherin junctions. Further, endo -lysosomal escape of Fe 3 O 4 to cytosol exerted ROS scavenging effect and protected endothelial cells from apoptosis. VE-Cadherin maintenance and cell rescue together preserved the endothelial barrier and subsequently decreased leukocytes extravasation and intracardial hemorrhage, alleviated cardiomyocyte apoptosis and eventually improved cardiac function. This work demonstrates a practical platform for the treatment of reperfusion injury by enhancing targeted release of drugs to injured endothelium. [ABSTRACT FROM AUTHOR]

• L-arginine and glycine can serve as both thermodynamic and kinetic inhibitors. • Glycine presents a dosage threshold for best inhibition of hydrate formation. • Inhibition synergy is found for hydrophilic amino acids with kinetic inhibitors. • Combining glycine and VC-713 gives the best synergistic inhibition of hydrates. The effects of hydrophilic amino acids on hydrate formation are a global hot spot of research, and yet the mechanisms behind such effects need to be further investigated. The mechanism of synergism between hydrophilic amino acids and hydrate kinetic inhibitors has not been clarified. Given the aforementioned, this research analyzes the effects of L-arginine, glycine, and their combination with PVP K90 and VC-713 on the formation of tetrahydrofuran (THF) hydrates, and manages to systematically reveal the relevant mechanisms by integrating various experimental methods. It is shown that L-arginine and glycine can disturb water molecules and reduce their activity, and thus they present both kinetic and thermodynamic inhibition effects. The combinations of 0.5 wt%–5.0 wt% L-arginine and glycine with 0.5 wt%–1.0 wt% kinetic inhibitors are found with synergistic inhibition effects on hydrate formation, and the combination of 4.0 wt% glycine with 1.0 wt% VC-713 is associated with the best synergistic inhibition performance. [ABSTRACT FROM AUTHOR]

The rapid loss of global biodiversity can greatly affect the functioning of above-ground components of ecosystems. However, how such biodiversity losses affect below-ground communities and linkages to soil carbon (C) sequestration is unclear. Here, we describe how losses in plant functional groups ( PFGs) affect soil microbial and nematode communities and net ecosystem exchange ( NEE) in a 4-year removal experiment conducted on the Mongolian plateau, the world's largest remaining natural grassland., Our results demonstrated that the biomasses or abundances of most components of the two below-ground communities (microbes and nematodes) were negatively affected by PFG loss and were positively related to above-ground plant biomass. The removal of dominant PFGs (perennial bunchgrasses and perennial rhizomatous grasses) reduced the biomass or abundance of below-ground community components while removal of less dominant PFGs (perennial forbs and annuals/biennials) did not change or increased the biomass or abundance of below-ground community components., The biomass-based ratio of fungal to bacterial microbes and the number-based ratio of fungal-feeding to bacterial-feeding nematodes decreased with increasing PFG losses. Variation partitioning analyses showed that the identity of PFGs together with above-ground plant biomass explained most of the total variation in soil microbes and that the identity of PFGs and above-ground plant biomass together with nematode food resources explained most of the total variation in soil nematodes. The increase in NEE with PFG loss was mainly explained by decreases in above-ground plant biomass and the ratio of fungi to bacteria., Synthesis. The shift of below-ground communities from a fungal-based to a bacterial-based energy channel as PFG richness decreases indicates that less diverse grassland ecosystems will have lower nutrient retention and hence be more sensitive to land-use or climate change. The dominant effects of above-ground plant biomass and below-ground communities on NEE indicate that PFG loss resulting from land-use or climate change has the potential to reduce C sequestration in semi-arid grassland soils. These findings suggest that predictive models may need to consider the composition of above-ground and below-ground communities in order to accurately simulate the dynamics of CO2 fluxes in terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Human activities have substantially enhanced the availability of important nutrient elements such as nitrogen (N), phosphorus (P), and potassium (K) in ecosystems worldwide. However, how the concurrent increase in all of these nutrients will affect greenhouse gas (that is, CO, NO, CH) levels remains unknown. In a temperate steppe of northern China, a 2-year field experiment was conducted to examine the effects of multi-nutrient additions on GHG fluxes from 2009 to 2010. Four levels of annual nutrient loads were mimicked: 0 g NPK (control), 15.5 g P m and 19.5 g K m as KHPO (PK), 10 g N m as NHNO plus PK (10N + PK), and 20 g N m plus PK (20N + PK) per year. The results show that multi-nutrient additions led to significant increases in net primary production (NPP) and soil temperature (ST), a significant decrease in soil moisture (SM) in 2010, and no significant changes in other soil parameters. Seasonal patterns differed greatly for different GHG fluxes in response to different nutrient treatments, largely as a result of differences in influential factors. The 10N + PK treatment significantly increased CO uptake, whereas the 20N + PK treatment significantly decreased CO uptake. The application of P and K without additional N significantly enhanced CH uptake, whereas the two N + PK treatments significantly enhanced NO emissions. Significant positive, linear relationships were found between cumulative CO uptake and soil total nitrogen (TN), microbial biomass carbon, and microbial biomass nitrogen, whereas significant negative, linear relationships were found with NPP, SM, and the C/N ratio. Significant positive, linear relationships were found between cumulative NO emission and ST, TN, NPP, and total organic carbon, whereas no relationships were found between cumulative CH uptake and any soil parameters. CO flux was related to NO flux temporally, to a certain extent, for all the treatments. In the control, NO flux showed a negative, linear relationship with CH flux, whereas no regular relationships were detected between CO and CH fluxes in any treatment. Our findings imply that increasing nutrient deposition will change the magnitude, patterns, and relationships among GHG uptakes and emissions in the future. [ABSTRACT FROM AUTHOR]

Abstract: Ammonia (NH3) is an important component of the nitrogen (N) cycle in terrestrial ecosystems and is a significant atmospheric pollutant. Results from studies of ammonia emissions from semi-arid grasslands have been infrequently reported although these emissions may be increasing rapidly with a subsequent increase in atmospheric N deposition. Moreover, whether N deposition regimes (fertilization vs. atmospheric N deposition) influence NH3 volatilization from soil is unclear. We conducted an N deposition experiment in an Inner Mongolian grassland with nine levels of N addition (0, 1, 2, 3, 5, 10, 15, 20, and 50 g N m−2 yr−1) and two additional N regimes: a two-pulse addition (N2) simulating fertilization and monthly addition (N12) simulating atmospheric N deposition. We investigated NH3 volatilization from the soil in 2010 and 2011 after the addition of N. NH3 volatilization rates significantly increased with increasing intensities of N addition for both the two-pulse (R 2 = 0.993, P < 0.001) and monthly addition (R 2 = 0.992, P < 0.001). Cumulative NH3 emissions during the growing season were higher for the monthly addition regime (1.28–3.54 g N m−2) than the two-pulse addition regime (1.12–2.71 g N m−2) (P < 0.001), and there was a significant inter-annual variation in both of the N addition regimes. NH3 volatilization rates and cumulative emissions were significantly positively correlated with soil ammonium concentration in both N addition regimes. Overall, a higher level of N application at a higher frequency resulted in higher NH3 emissions indicating that the assessments made in most N fertilization experiments will underestimate the effects of N deposition on NH3 emissions from soils as well as on N cycles. [Copyright &y& Elsevier]

Whether the current pharmacogenetic knowledge of clopidogrel could be translated into Chinese clinical practice is yet to be defined. To address this issue, we assessed the relation of single nucleotide polymorphisms within genes modulating clopidogrel absorption (ABCB1), metabolic activation (CYP2B6, CYP2D6, CYP3A4, CYP2C9, and CYP2C19), and biologic activity (P2RY12) to the response of clopidogrel as measured by ex-vivo platelet reactivity and ischemic events during half a year of follow-up. Only CYP2C19∗2 and ∗3, of the investigated polymorphisms, were associated with postclopidogrel platelet aggregation and the presence of high platelet reactivity. Moreover, the effect of the CYP2C19∗2 versus the ∗3 allele on platelet reactivity did not differ. Although the carriage of one or two CYP2C19 loss-of-function alleles, irrespective of the CYP2C19∗2 or ∗3 allele, increased the propensity for high platelet reactivity, only the two loss-of-function allele carriage was associated with clinical outcome in the first 6 months. [ABSTRACT FROM AUTHOR]

The Eurasian steppe has long been subject to grazing by domestic ungulates at high levels, resulting in widespread deterioration of biodiversity and ecosystem services. While abundant evidence demonstrates that heavy grazing alters the ecosystem structure and function of grasslands, research on how grazing specifically affects ecosystem functioning and stoichiometry on broad scales is scarce because of a lack of adequate ungrazed reference sites., We examined the effects of grazing on ecosystem functioning and C : N : P stoichiometry across a precipitation gradient along the 700 km China- Mongolia transect ( CMT), covering three community types: meadow steppe, typical steppe and desert steppe., Long-term grazing has dramatically altered the C, N and P pools and stoichiometry of steppe ecosystems along the CMT. Grazing reduced the C, N and P pools in above-ground biomass and litter, while the responses in below-ground biomass and soil C, N and P pools to grazing differed substantially among community types., Grazing increased N content and decreased C : N ratios in all plant compartments, suggesting accelerated N cycling. The altered C : N : P stoichiometry may be explained by changes in the composition of species and functional groups as well as increased foliar N and P contents for the same species in grazed communities., Synthesis and applications. Plant stoichiometric responses to grazing ranged from large in the meadow steppe to small in the typical steppe to generally insignificant in the desert steppe, implying that different underlying mechanisms operated along the regional precipitation gradient. Our findings suggest that reducing the stocking rate and restoring the vastly degraded steppes are essential to sustain native steppe biodiversity, ecosystem functioning and biological capacity for mitigating the impact of climate change in the Inner Mongolia grassland. [ABSTRACT FROM AUTHOR]

Abstract: The influences of winter climate on terrestrial ecosystem processes have been the subject of growing attention, which is necessary to make the predictions about ecological responses to global warming in the future. However, little information can be found about the impacts of a large range of soil temperature fluctuation (e.g. −10 to 5°C) over winter on the soil nitrogen (N) dynamics in the field. In the present study, we employed an intact soil core in situ incubation technique, and measured soil N mineralization and nitrification rates under three plant communities, i.e. a grassland, a shrub and a plantation, during the non-growing season (October 2004–April 2005) in Inner Mongolia, China. Our results demonstrate the significant effects of different plant communities on soil net N mineralization and the great temporal variations of soil N dynamics during the incubation period. The mean soil net N mineralization rates were 0.93, 0.77 and −1.28mg Nm−2 d−1, respectively, in the grassland, shrub and plantation. The mean soil NH4 +-N in the three plant communities declined by 40%, but the mean soil NO3 −-N increased by 190% by the end of the incubation compared with their initial concentrations at the beginning of incubation. The differences in plant communities significantly affected their soil N mineralization rates, accumulations and turnover rates, which followed the order: grassland>shrub>plantation. During the winter time, the studied soils experienced the three phases consisting of mild freezing (−7 to −2°C soil), deep freezing (approximately −10°C soil) and freeze–thaw (−2 to 5°C soil). The results suggest that temporal variations of soil N mineralization are positively affected by the soil temperature and the soil nitrification is dominant in the N transformation process during the non-growing season. Our study indicates that the soil N mineralization over winter can make a substantial contribution to the mineral N pool that plants are able to utilize in the upcoming spring, but may also pose a great risk of mineral N leaching loss if great rainfalls occur during spring and early summer. [Copyright &y& Elsevier]

• We assess effect of long-term N addition on plant uptake traced by three 15N labels. • Species that continue to be dominant with N addition show high N-uptake plasticity. • Either dominant or minor plant species used N from the most abundant soil N form. • The N addition frequency affects N uptake by interacting with addition level. Nitrogen (N) deposition can significantly alter plant diversity and soil N status and cycling. However, there is rare information about the responses of plant N uptake of coexisting species to N deposition, which could facilitate the understanding of these N-induced ecosystem changes, particularly when taking N addition frequency into consideration. We assessed the uptake rates of N of various chemical forms (both inorganic and organic N) among coexisting plant species in response to N enrichment, using in situ stable isotope labeling techniques (15N-labeled ammonium, 15N-labeled nitrate and 13C-15N-labeled glycine), through a long-term N deposition experiment with monthly and biannual N addition frequencies in a temperate grassland. The plants of all three targeted species took up much greater inorganic N than amino acid N (93.4–99.4 % vs. 0.6–6.6 % in relative contributions to the total N uptake). The most abundant soil N form that originally was NH 4 +, was shifted to be NO 3 − under low and moderate N additions and back to be NH 4 + at high addition level. Plants of not only dominant but also minor species predominantly took up N from the most abundant soil N form along N addition gradient. The dominant species Leymus chinensis , which continued to maintain its dominance under N enrichment, exhibited the ability to capture N of all different forms to tolerate and survive in a wide range of soil N environments. In contrast, another dominant species Stipa grandis , which was losing its dominance with N addition, showed the acquisition capacity of single N form in response to increased N inputs. It should be noted that there were interaction effects of N addition frequency and level on plant N uptake rates. Plant N uptake patterns and acquisition strategies could have important consequences for changes in ecosystem biodiversity and function under current and future N deposition scenarios. [ABSTRACT FROM AUTHOR]

As more attentions have been paid to microbial taxonomic community structure along altitudinal gradients, the knowledge of the altitudinal variations in microbial functional structure in terrestrial ecosystems is limited. More importantly, the dominant assembly processes that drive altitudinal variations in both taxonomic composition and functional structure remain unclear. To fill the gaps, we integrated soil prokaryotic taxonomic community structure, functional community structure and community assembly processes along an altitudinal gradient into a comprehensive understanding. The results revealed that both taxonomic community structure and core functional community structure of soil prokaryotic microbes significantly differed across altitudes. We detected the core functional groups associated with the redox reactions essential for microbial metabolism and biogeochemical cycles across altitudes. Chemoheterotrophy and photoautotrophy were dominant in abundance, indicating the important roles of primary energy metabolism for soil prokaryotic community. The whole prokaryotic community taxonomic composition was dominantly shaped by dispersal limitation (governing 74% of spatial turnover). The variation of functional structure was primarily caused by environmental selection, while the taxonomic variation within individual functional groups was weakly related to selection but mainly driven by drift. These results are critical for predicting the future dynamics of soil microbial community in the face of disturbances. [ABSTRACT FROM AUTHOR]

• Root trait dynamics were assessed biweekly in a cold Alpine grassland for 3-years. • Precipitation had a time lag effect on root traits. • Accumulative air temperature exerted synchronic effects on root traits. • SRL in non-growing season was significantly 17 % higher than that in growing season. Root trait dynamics can reflect the adjustment in the strategy of plant roots in resource acquisition and energy storage when responding to climatic fluctuations. Under global change, the responses of root traits in climate sensitive ecosystems, e.g. high-elevation and cold Alpine ecosystems, remain unclear. To identify how climatic fluctuations drive the variations in the root traits in a Tibetan alpine grassland, we intensively investigated the temporal dynamic of root traits by biweekly measuring root length, root biomass and specific root length for three continuous years. The SRL showed strong seasonal patterns across three years, which did not support SRL considered as a constant in previous root system modeling, while as hypothesized, mean SRL in non-growing seasons was significantly higher than that in growing seasons by 17 %. The accumulative air temperature of growing or non-growing season exerted synchronic effects on the changes in root traits. Nevertheless, precipitation was observed to have the lag effects on root traits, showing that January-April accumulative precipitation was a major driver for the variations in the root length and root biomass respectively peaking in July and June each year. Distinguishingly, root length relied on the lag effect of precipitation; however, for root biomass, the continuous accumulative precipitation together with peak month, i.e. the January-June accumulative precipitation, was also significantly vital. Our results would have an important implication for predicting responses of belowground carbon cycling to global climate change. [ABSTRACT FROM AUTHOR]

Nutrient resorption processes in the plants infected by pathogen remain poorly understood. Huanglongbing (HLB) is a destructive disease of citrus. HLB-pathogen 'Candidatus Liberibacter asiaticus' grows specifically in the phloem of hosts and may cause problems in the plant vascular system after infection. Therefore, it brings a great concern about the phloem nutrient transport and nutrient intra-cycling in HLB-affected plants. We investigated the effects of 'Ca. L. asiaticus' infection on nitrogen (N) and phosphorus (P) concentrations and resorption in different citrus species (i.e. Citrus reticulata, Citrus limon and Citrus maxima). HLB-pathogen infection had distinctive impacts on nutrient resorption in different species. P resorption efficiency substantially decreased in infected C. reticulata plants relative to the healthy plants in summer, which may account for the marked decrease in the average fruit yield. P resorption was more efficient in infected C. limon plants than in the healthy plants. However, for C. maxima plants, HLB had no significant effects on N:P ratio in live leaves and resorption efficiency as well as on fruit yield. Keeping efficient internal nutrient cycling can be a strategy of citrus species being tolerant to HLB. [ABSTRACT FROM AUTHOR]