Search

Although phylogenetic distance between native and exotic species has a close link with their interactions, it is still unclear how environmental stresses and species interactions influence the relationship between phylogenetic distance and biological invasions. Here we assessed the effect of invader–native phylogenetic distance on the growth of the invader (Symphyotrichum subulatum) under three levels of drought (no, moderate, or intense drought). Under no drought, interspecific competition between close relatives was the dominant process and native communities more closely related to the invader showed higher resistance to invasion, supporting Darwin's naturalization hypothesis. In contrast, under intense drought, facilitation between close relatives by mutualism with arbuscular mycorrhizal fungi (AMF) became more important, and the invader became more successful in their more closely related native communities, supporting the preadaptation hypothesis. The colonization rate of AMF of the invader was higher in more closely related native communities regardless of the drought treatment, but it was only positively related to invader biomass under intense drought. Therefore, the shift of species interactions from competition to facilitation may be ascribed to the promotion of AMF to invasion occurring under intense drought, which leads to the effect of closely related natives on the invader shifting from negative to positive. Our results provide a new angle to resolve Darwin's naturalization conundrum from the change of species interactions along a stress gradient, and provide important clues for invasion management when species interactions change in response to global climatic change. [ABSTRACT FROM AUTHOR]

Since Darwin's time, degree of ecological similarity between exotic and native species has been assumed to affect the establishment success or failure of exotic species. However, a direct test of the effect of exotic–native similarity on establishment of exotics is scarce because of the difficulty in recognizing failures of species to establish in the field. Here, using a database on the establishment success and failure of exotic fish species introduced into 673 freshwater lakes, we evaluate the effect of similarity on the establishment of exotic fishes by combining phylogenetic and functional information. We illustrate that, relative to other biotic and abiotic factors, exotic–native phylogenetic and functional similarities were the most important correlates of exotic fish establishment. While phylogenetic similarity between exotic and resident fish species promoted successful establishment, functional similarity led to failure of exotics to become established. Those exotic species phylogenetically close to, but functionally distant from, native fishes were most likely to establish successfully. Our findings provide a perspective to reconcile Darwin's naturalization conundrum and suggest that, while phylogenetic relatedness allows exotic fish species to pre‐adapt better to novel environments, they need to possess distinct functional traits to reduce competition with resident native fish species. [ABSTRACT FROM AUTHOR]

Elton's biotic resistance hypothesis, which posits that diverse communities should be more resistant to biological invasions, has received considerable experimental support. However, it remains unclear whether such a negative diversity–invasibility relationship would persist under anthropogenic environmental change. By using the common ragweed (Ambrosia artemisiifolia) as a model invader, our 4‐year grassland experiment demonstrated consistently negative relationships between resident species diversity and community invasibility, irrespective of nitrogen addition, a result further supported by a meta‐analysis. Importantly, our experiment showed that plant diversity consistently resisted invasion simultaneously through increased resident biomass, increased trait dissimilarity among residents, and increased community‐weighted means of resource‐conservative traits that strongly resist invasion, pointing to the importance of both trait complementarity and sampling effects for invasion resistance even under resource enrichment. Our study provides unique evidence that considering species' functional traits can help further our understanding of biotic resistance to biological invasions in a changing environment. [ABSTRACT FROM AUTHOR]

Summary: The study of islands has made substantial contributions to the development of evolutionary and ecological theory. However, we know little about microbial community assembly on islands. Using soil microbial data collected from 29 lake islands and nearby mainland, we examined the assembly mechanisms of soil bacterial and fungal communities among and within islands. We found that deterministic processes, especially homogeneous selection, tended to be more important in shaping the assembly of soil bacterial communities among islands, while stochastic processes tended to be more important within islands. Moreover, increasing island area increased the importance of homogeneous selection, but reduced the importance of variable selection, for soil bacterial community assembly within islands. By contrast, stochastic processes tended to dominate soil fungal community assembly both among and within islands, with dispersal limitation playing a more important role within than among islands. Our results highlight the scale‐ and taxon‐dependence of insular soil microbial community assembly, suggesting that spatial scale should be explicitly considered when evaluating the influences of habitat fragmentation on soil microbial communities. [ABSTRACT FROM AUTHOR]

A central aim of invasion biology has been to identify key functional differences between native and exotic species to determine which traits may be responsible for invasion success and impacts. There are two primary ways that differences may exist between native and exotic species—the traits of the local species pools may differ, or the way that the traits interact with their environment may differ.We explored leaf nutrient concentrations as functional traits that directly link to plant metabolic processes by sampling healthy, mature leaves from 119 native and exotic taxa across a wide range of successional statuses in New Jersey, USA. Leaf nutrient concentration data (carbon, calcium, magnesium, nitrogen, phosphorus, potassium) were paired with long‐term community dynamics from the Buell–Small Succession Study to evaluate abundance‐weighted trait values over succession for native and exotic species.After accounting for differences across growth forms, there were minimal differences in foliar nutrients based on plant origin, with only lower leaf carbon and higher leaf potassium in exotic species. However, these differences were not sufficient to generate overall differences between native and exotic species in a multivariate analysis. In contrast, the successional trajectories of the abundance‐weighted trait values for most leaf nutrients differed strongly between native and exotic plants. While this pattern may be partially attributable to variation in the species pool for carbon and potassium, successional processes generated differential sorting, suggesting underlying differences in how the same traits function in native and exotic assemblages.Synthesis. These results suggest that both variation in the species pool and variation in the successional selection of plant traits can generate functional differences between native and exotic plants. Assessments of trait differences between native and exotic species will require information on traits and plant performance to unambiguously link traits to function in dynamic plant communities. Analysis of a long‐term dataset suggests that both variation in the species pool and variation in the successional selection of plant traits can generate functional differences between native and exotic plants. Assessments of trait differences between native and exotic species will require information on traits and plant performance to unambiguously link traits to function in dynamic plant communities. [ABSTRACT FROM AUTHOR]

Abstract A novel semi-direct monocular visual simultaneous localization and mapping (SLAM) system is proposed to maintain the fast performance of a direct method and the high precision and loop closure capability of a feature-based method. This system extracts and matches Oriented FAST and Rotated BRIEF features in a keyframe and tracks a non-keyframe via a direct method without the requirement of extracting and matching features. A keyframe is used for global or local optimization and loop closure, whereas a non-keyframe is used for fast tracking and localization, thereby combining the advantages of direct and feature-based methods. A monocular visual-inertial SLAM system that fuses inertial measurement data with visual SLAM is also proposed. This system successfully recovers the metric scale successfully. The evaluation on datasets shows that the proposed approach accomplishes loop closure detection successfully and requires less time to achieve accuracy comparable with that of feature-based method. The physical experiment demonstrates the feasibility and robustness of the proposed SLAM. The approach achieves good balance between speed and accuracy and provides valuable references for design and improvement of other SLAM methods. Highlights • A novel semi-direct monocular visual SLAM system is proposed. • The SLAM system also fuses inertial data to form a visual-inertial SLAM. • The method maintains the advantages of the direct and the feature-based method. • Comparative results of semi-direct SLAM are given. [ABSTRACT FROM AUTHOR]

High-alumina fly ash (HAFA) is a special solid waste because it consists of more than 40 wt.% alumina and 40 wt.% silica, which can be applied in the alumina extraction and preparation of Al–Si composite if the Al/Si weight ratio can be elevated to a high level (> 2.55). However, traditional desilication cannot satisfy this demand because of its low desilication ratio and the presence of abundant impurities. Therefore, this study systematically analyzed acid activation of desilicated HAFA (DHAFA) to extensively remove amorphous silica and impurities. The efficient desilicated ratio (EDR) is first applied to characterize DHAFA. Moreover, the effects of different factors on the mineralogical structure, pore structure, specific surface area and extraction of Al and Fe were investigated. The results of energy-dispersive X-ray spectroscopy and X-ray diffraction indicate that zeolites on the external and internal portion of DHAFA can be decomposed. Results also indicated that increased acid concentration, reaction temperature, and reaction time elevated the EDR values from 11.1% to 29.51% and evidently increased the Al 3 + /Fe 3 + leaching ratios. The removal of zeolites and reactive Al 3 + /Fe 3 + result in an increase of specific surface area from 23.86 m 2 /g to 70 m 2 /g and formation of more mesopores (3–4 nm). X-ray fluorescence results revealed that the Al/Si weight ratio can be elevated from 1.2 to approximately 2.85. [ABSTRACT FROM AUTHOR]

Darwin’s naturalization hypothesis (DNH), which predicts that alien species more distantly related to native communities are more likely to naturalize, has received much recent attention. The mixed findings from empirical studies that have tested DNH, however, seem to defy generalizations. Using meta-analysis to synthesize results of existing studies, we show that the predictive power of DNH depends on both the invasion stage and the spatial scale of the studies. Alien species more closely related to natives tended to be less successful at the local scale, supporting DNH; invasion success, however, was unaffected by alien–native relatedness at the regional scale. On the other hand, alien species with stronger impacts on native communities tended to be more closely related to natives at the local scale, but less closely related to natives at the regional scale. These patterns are generally consistent across different ecosystems, taxa and investigation methods. Our results revealed the different effects of invader–native relatedness on invader success and impact, suggesting the operation of different mechanisms across invasion stages and spatial scales. [ABSTRACT FROM AUTHOR]

Whether plant communities in a given region converge towards a particular stable state during succession has long been debated, but rarely tested at a sufficiently long time scale. By analysing a 50-year continuous study of post-agricultural secondary succession in New Jersey, USA, we show that the extent of community convergence varies with the spatial scale and species abundance classes. At the larger field scale, abundance-based dissimilarities among communities decreased over time, indicating convergence of dominant species, whereas incidence-based dissimilarities showed little temporal tend, indicating no sign of convergence. In contrast, plots within each field diverged in both species composition and abundance. Abundance-based successional rates decreased over time, whereas rare species and herbaceous plants showed little change in temporal turnover rates. Initial abandonment conditions only influenced community structure early in succession. Overall, our findings provide strong evidence for scale and abundance dependence of stochastic and deterministic processes over old-field succession. [ABSTRACT FROM AUTHOR]

Darwin's naturalisation conundrum describes the paradox that the relatedness of exotic species to native residents could either promote or hinder their success through opposing mechanisms: niche pre-adaptation or competitive interactions. Previous studies focusing on single snapshots of invasion patterns have provided support to both sides of the conundrum. Here, by examining invasion dynamics of 480 plots over 40 years, we show that exotic species more closely related to native species were more likely to enter, establish and dominate the resident communities, and that native residents more closely related to these successful exotics were more likely to go locally extinct. Therefore, non-random displacement of natives during invasion could weaken or even reverse the negative effects of exotic-native phylogenetic distances on invasion success. The scenario that exotics more closely related to native residents are more successful, but tend to eliminate their closely related natives, may help to reconcile the 150-year-old conundrum. [ABSTRACT FROM AUTHOR]

Ecological communities often transition from phylogenetic and functional clustering to overdispersion over succession as judged by space-for-time substitution studies. Such a pattern has been generally attributed to the increase in competitive exclusion of closely related species with similar traits through time, although colonisation and extinction have rarely been examined. Using 44 years of uninterrupted old-field succession in New Jersey, USA, we confirmed that phylogenetic and functional clustering decreased as succession unfolded, but the transition was largely driven by colonisation. Early colonists were closely related and functionally similar to residents, while later colonists became less similar to the species present. Extirpated species were generally more distantly related to residents than by chance, or exhibited random phylogenetic/functional patterns, and their relatedness to residents was not associated with time. These results provide direct evidence that the colonisation of distant relatives, rather than extinction of close relatives, drives phylogenetic and functional overdispersion over succession. [ABSTRACT FROM AUTHOR]

Identifying the factors determining the success of invasive species is critical for management of biological invasions. Darwin's naturalization conundrum states that exotic species closely related to natives should be successful because of a shared affinity for local environmental conditions, but at the same time close relatives often compete more intensively, limiting 'niche' opportunities for the invaders. Previous studies have generally considered these two 'opposing' hypotheses as mutually exclusive, yet evidence for both of them abounds, indicating a practical dilemma for management of biological invasions., In this study, we sowed the seeds of the invasive exotic Ambrosia artemisiifolia L. into 369 experimental plant communities to mimic an introduction of the exotics into a series of new habitats. We further linked the establishment and growth performance of the invader in these experimental communities to the phylogenetic relatedness between the invader and the community residents where it was introduced., We found that the probability of invader establishment declined with increasing phylogenetic distance between the invader and residents, whereas the average size of surviving invader individuals increased with the phylogenetic distance., These results can be at least partly explained by the observations that close relatives tend to create similar soil microhabitat through harbouring similar soil enzymes (e.g. alkaline and acid phosphatases) benefiting invader establishment and that intense competitive interactions between the invader and its close relatives suppressed exotic growth., Synthesis and applications. This study presents the first experimental evidence that phylogenetic relatedness has contrasting effects on different aspects of invader success, thus shedding light on the long-standing Darwin's naturalization conundrum. Moreover, our findings also have important implications for management of plant invasions: for controlling invasive species characterized by high establishment probability, native species distantly related to the invasive species can be planted in sites surrounding the invasion foci, whereas the opposite seems to be true for controlling those characterized by large individual size. [ABSTRACT FROM AUTHOR]

Results of previous wind tunnel testing have shown that the span-wise correlation of the buffeting force on bridge deck is greater than that of the turbulent components. Due to the limitation of wind tunnel size and model scale, above-mentioned results were usually obtained for smaller separation along the span and the turbulent flow was generated by passive method. In order to study of the span-wise correlation of the buffeting force with large separation and different turbulent flow field, thorouphty lift buffeting force is taken for instance in this paper. Theoretical analysis method is employed to establish a reasonable mathematic model, and then the difference of the span-wise correlation between buffeting force and wind fluctuations was investigated by means of the wind spectra simkulation in wind tunnel and in natural atmosphere, respectively. The buffeting force that better correlated span-wise than the wind fluctuations applies only to certain interval in turbulent flow simulated in wind tunnel, while as in the natural atmospheric turbulent field, the correlation of buffeting force is between the longitudinal and vertical oncoming flow fluctuations. Finally, the empirical coherence function proposed by Davenport is employed to verify the validity of the analysis method. [ABSTRACT FROM AUTHOR]

1. An important factor limiting the wider application of constructed ecosystems for bioremediation of sites contaminated by toxic chemicals is their relatively low efficiency of contaminant removal. Although there is growing evidence that species-rich ecosystems may out-perform species-poor ecosystems in removing excessive nutrients from water through niche partitioning, it remains unknown whether diverse ecosystems are more efficient in removing toxic chemicals from the environment, and if they are, by what mechanisms diverse ecosystems can lead to enhanced removals. 2. In this study, we exposed aquatic algal microcosm ecosystems of varying species richness to a realistic cadmium (Cd) contamination scenario. We explore the mechanisms of Cd removal by assemblages with differing diversity and consider the potential role of diversity on Cd bioremediation. 3. Our results suggest that Cd removal efficiencies of the algal microcosms increased with species richness. Furthermore, we found that 45% of all polycultures out-performed the monocultures of their most efficient component species in removing Cd from the growth substrates (referred as to 'over Cd removal'). However, the average Cd removal efficiency of the most diverse (eight-species) polycultures was not higher than that of the most efficient monoculture (i.e. the algal species most tolerant to Cd) in this study. We also showed that the observed over Cd removal could be largely ascribed to the enhanced biomass yields of the polycultures, which were mainly driven by the positive effects of Cd-tolerant species on Cd-sensitive species. 4. Synthesis and applications. This study demonstrates that some algal polycultures containing both Cd-tolerant and Cd-sensitive species may show over Cd removal through facilitation provided by Cd-tolerant species. These polycultures are likely to be assembled and applied to achieve Cd removals higher than those of their most efficient component species in monoculture. Given that species-rich ecosystems tend to be more environmentally stable than ones with fewer species, it would be prudent to employ diverse polycultures rather than risk the loss of individual monocultures. [ABSTRACT FROM AUTHOR]

Abstract: The cubic phase LiMn2O4 spinel is synthesized via a directly soft chemistry method via hydrothermal reaction of Mn(NO3)2, LiOH and H2O2 at 383K for 5–10h, more favorable to control the nanocrystalline structure with well-defined pore-size distribution and high surface area than traditional solid-phase reaction at high temperature. Further, the 1D MnO2 nanorod ion-sieves with lithium ion selective adsorption property is prepared by the acid treatment process to completely extract lithium ions from the LiMn2O4 lattice. The effects of hydrothermal conditions on the nanostructure, chemical stability and ion-exchange property of the LiMn2O4 spinel and MnO2 ion-sieve are examined via powder X-ray diffraction (XRD), N2 adsorption–desorption at 77K, high-resolution transmission electron microscopy (HRTEM), selected-area electron diffraction (SAED) and lithium ion selective adsorption measurements. The results show that the 1D MnO2 nanorods might be utilized in lithium extraction from aqueous environment including brine, seawater and waste water. [Copyright &y& Elsevier]

Abstract: Mesoporous titania nanoribbons were synthesized via an optimized soft hydrothermal process and the derived titania ion-sieves with lithium selective adsorption property were accordingly prepared via a simple solid-phase reaction between Li2CO3 and TiO2 nanomaterials followed by the acid treatment process to extract lithium from the Li2TiO3 ternary oxide precursors. First, mesoporous titania nanoribbons were prepared and the formation mechanism was discussed; second, the physical chemistry structure and texture were characterized by powder X-ray diffraction (XRD), (high-resolution) transmission electron microscopy (TEM/HRTEM), selected-area electron diffraction (SAED) and N2 adsorption–desorption analysis (BET); third, the lithium selective adsorption properties were tested by the adsorption isotherm, adsorption kinetics measurement and demonstrated with the distribution coefficient of a series of alkaline and alkaline–earth metal ions. [Copyright &y& Elsevier]

Abstract: β-MnO2, spinel-type Li4Mn5O12 and pure cubic phase MnO2 nanorod, with the size about 20–140nm in diameter and 0.8–4μm in length, were synthesized via a combination of hydrothermal synthesis and low temperature solid-phase reaction, more favorable to control the nanocrystalline structure with well-defined pore size distribution and high surface area than the traditional high temperature calcination process. Further, the MnO2 ion-sieves with lithium selective adsorption property were prepared by the acid treatment process to completely extract lithium from the spinel Li4Mn5O12 precursor with little change to the Mn–O lattice structure and the 1-D nanorod morphology. The effects of hydrothermal and solid-phase reaction process on the nanostructure, chemical stability and ion-exchange property of the ion-sieve material were examined with powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), N2 adsorption–desorption at 77K, and Li+ selective adsorption measurements. The lithium selective adsorption capacity was improved remarkably to 6.62mmolg−1 at equilibrium and about 5mmolg−1 at the initial lithium concentration of only 5.0mmoll−1, which is significant for lithium extraction from aqueous solutions with very low lithium content. [Copyright &y& Elsevier]

Background: Immune checkpoint inhibitors (ICIs) are playing a significant role in the treatment of hepatocellular carcinoma (HCC). This study aims to explore the prognostic value of alpha-fetoprotein (AFP) and initial tumor shape irregularity in patients treated with ICIs.In this retrospective, multi-center study, 296 HCC patients were randomly divided into the training set and the validation set in a 3:2 ratio. The training set was used to evaluate prognostic factors and to develop an easily applicable ATSI (AFP and Tumor Shape Irregularity) score, which was verified in the validation set.The ATSI score was developed from two independent prognostic risk factors: baseline AFP ≥ 400 ng/ml (HR 1.73, 95% CI 1.01–2.96, P = 0.046) and initial tumor shape irregularity (HR 1.94, 95% CI 1.03–3.65, P = 0.041). The median overall survival (OS) was not reached (95% CI 28.20–NA) in patients who met no criteria (0 points), 25.8 months (95% CI 14.17–NA) in patients who met one criterion (1 point), and 17.03 months (95% CI 11.73–23.83) in patients who met two criteria (2 points) (P = 0.001). The median progression-free survival (PFS) was 10.83 months (95% CI 9.27–14.33) for 0 points, 8.03 months (95% CI 6.77–10.57) for 1 point, and 5.03 months (95% CI 3.83–9.67) for 2 points (P < 0.001). The validation set effectively verified these results (median OS, 37.43/24.27/14.03 months for 0/1/2 points, P = 0.028; median PFS, 13.93/8.30/4.90 months for 0/1/2 points, P < 0.001).The ATSI score can effectively predict prognosis in HCC patients receiving ICIs.Methods: Immune checkpoint inhibitors (ICIs) are playing a significant role in the treatment of hepatocellular carcinoma (HCC). This study aims to explore the prognostic value of alpha-fetoprotein (AFP) and initial tumor shape irregularity in patients treated with ICIs.In this retrospective, multi-center study, 296 HCC patients were randomly divided into the training set and the validation set in a 3:2 ratio. The training set was used to evaluate prognostic factors and to develop an easily applicable ATSI (AFP and Tumor Shape Irregularity) score, which was verified in the validation set.The ATSI score was developed from two independent prognostic risk factors: baseline AFP ≥ 400 ng/ml (HR 1.73, 95% CI 1.01–2.96, P = 0.046) and initial tumor shape irregularity (HR 1.94, 95% CI 1.03–3.65, P = 0.041). The median overall survival (OS) was not reached (95% CI 28.20–NA) in patients who met no criteria (0 points), 25.8 months (95% CI 14.17–NA) in patients who met one criterion (1 point), and 17.03 months (95% CI 11.73–23.83) in patients who met two criteria (2 points) (P = 0.001). The median progression-free survival (PFS) was 10.83 months (95% CI 9.27–14.33) for 0 points, 8.03 months (95% CI 6.77–10.57) for 1 point, and 5.03 months (95% CI 3.83–9.67) for 2 points (P < 0.001). The validation set effectively verified these results (median OS, 37.43/24.27/14.03 months for 0/1/2 points, P = 0.028; median PFS, 13.93/8.30/4.90 months for 0/1/2 points, P < 0.001).The ATSI score can effectively predict prognosis in HCC patients receiving ICIs.Results: Immune checkpoint inhibitors (ICIs) are playing a significant role in the treatment of hepatocellular carcinoma (HCC). This study aims to explore the prognostic value of alpha-fetoprotein (AFP) and initial tumor shape irregularity in patients treated with ICIs.In this retrospective, multi-center study, 296 HCC patients were randomly divided into the training set and the validation set in a 3:2 ratio. The training set was used to evaluate prognostic factors and to develop an easily applicable ATSI (AFP and Tumor Shape Irregularity) score, which was verified in the validation set.The ATSI score was developed from two independent prognostic risk factors: baseline AFP ≥ 400 ng/ml (HR 1.73, 95% CI 1.01–2.96, P = 0.046) and initial tumor shape irregularity (HR 1.94, 95% CI 1.03–3.65, P = 0.041). The median overall survival (OS) was not reached (95% CI 28.20–NA) in patients who met no criteria (0 points), 25.8 months (95% CI 14.17–NA) in patients who met one criterion (1 point), and 17.03 months (95% CI 11.73–23.83) in patients who met two criteria (2 points) (P = 0.001). The median progression-free survival (PFS) was 10.83 months (95% CI 9.27–14.33) for 0 points, 8.03 months (95% CI 6.77–10.57) for 1 point, and 5.03 months (95% CI 3.83–9.67) for 2 points (P < 0.001). The validation set effectively verified these results (median OS, 37.43/24.27/14.03 months for 0/1/2 points, P = 0.028; median PFS, 13.93/8.30/4.90 months for 0/1/2 points, P < 0.001).The ATSI score can effectively predict prognosis in HCC patients receiving ICIs.Conclusions: Immune checkpoint inhibitors (ICIs) are playing a significant role in the treatment of hepatocellular carcinoma (HCC). This study aims to explore the prognostic value of alpha-fetoprotein (AFP) and initial tumor shape irregularity in patients treated with ICIs.In this retrospective, multi-center study, 296 HCC patients were randomly divided into the training set and the validation set in a 3:2 ratio. The training set was used to evaluate prognostic factors and to develop an easily applicable ATSI (AFP and Tumor Shape Irregularity) score, which was verified in the validation set.The ATSI score was developed from two independent prognostic risk factors: baseline AFP ≥ 400 ng/ml (HR 1.73, 95% CI 1.01–2.96, P = 0.046) and initial tumor shape irregularity (HR 1.94, 95% CI 1.03–3.65, P = 0.041). The median overall survival (OS) was not reached (95% CI 28.20–NA) in patients who met no criteria (0 points), 25.8 months (95% CI 14.17–NA) in patients who met one criterion (1 point), and 17.03 months (95% CI 11.73–23.83) in patients who met two criteria (2 points) (P = 0.001). The median progression-free survival (PFS) was 10.83 months (95% CI 9.27–14.33) for 0 points, 8.03 months (95% CI 6.77–10.57) for 1 point, and 5.03 months (95% CI 3.83–9.67) for 2 points (P < 0.001). The validation set effectively verified these results (median OS, 37.43/24.27/14.03 months for 0/1/2 points, P = 0.028; median PFS, 13.93/8.30/4.90 months for 0/1/2 points, P < 0.001).The ATSI score can effectively predict prognosis in HCC patients receiving ICIs. [ABSTRACT FROM AUTHOR]

The radiative energy loss accounts for roughly 70% of the energy loss in the polysilicon chemical vapor deposition (CVD) reactors and therefore takes up to about 25% cost in the production of polysilicon used for solar cells. In this work, cold spray (CS) process was used to deposit Ag coating with ultra-high infrared reflectance on inner wall of the CVD reactor to minimize the radiative losses. To solve the bond strength problem of depositing soft coatings on hard substrate by CS, a Ni buffer layer with medium hardness was introduced. Results show that Ag coating can be successfully deposited with a porosity lower than 0.1%. Even the as-sprayed Ag coating has a high near-infrared reflectivity of 92% which was much higher than that of a well-polished substrate surface (65%) suggesting an excellent radiation energy saving capacity. The bond strength of the Ag coating is significantly increased from 3.7 MPa to 35.4 MPa and the thermal shock resistance is improved from 22 ± 3 to over 150 cycles by the Ni buffer layer. The scientific methodology demonstrated here can be a cost effective approach to reduce the radiation energy losses in the polysilicon-CVD industry. Unlabelled Image • Ag coating was cold sprayed on polysilicon CVD reactor wall for radiation energy saving. • A high near infrared reflectivity of 99.3% was achieved indicating 17 kWh/kg energy saving. • adhesion and thermal shock resistance was improved by several folds by the Ni buffer layer. • An economic radiation saving method was provided for polysilicon production. [ABSTRACT FROM AUTHOR]

Grime's competitive, stress‐tolerant, ruderal (CSR) theory predicts a shift in plant communities from ruderal to stress‐tolerant strategies during secondary succession. However, this fundamental tenet lacks empirical validation using long‐term continuous successional data. Utilizing a 60‐year longitudinal data of old‐field succession, we investigated the community‐level dynamics of plant strategies over time. Our findings reveal that while plant communities generally transitioned from ruderal to stress‐tolerant strategies during succession, initial abandonment conditions crucially shaped early successional strategies, leading to varied strategy trajectories across different fields. Furthermore, we found a notable divergence in the CSR strategies of alien and native species over succession. Initially, alien and native species exhibited similar ruderal strategies, but in later stages, alien species exhibited higher ruderal and lower stress tolerance compared to native species. Overall, our findings underscore the applicability of Grime's predictions regarding temporal shifts in CSR strategies depending on both initial community conditions and species origin. [ABSTRACT FROM AUTHOR]

The complex relationship between aboveground and belowground diversity and whether they act as surrogates for one another remains unresolved. Increasing evidence suggests that investigating phylogenetic diversity could provide valuable insights into the interplay between plants and soil microbes, but the proliferation of phylogenetic diversity metrics has hindered comparative studies and the identification of general patterns. To overcome this challenge, we implemented a multi‐dimensional framework that classifies phylogenetic diversity metrics into three dimensions: richness, divergence, and regularity, each of which captures different ecological aspects of species differences. Then we applied this framework to investigate the relationship between above and belowground diversity in a subtropical forest in eastern China. We found that phylogenetic diversity of plant and soil microbes, including bacteria and fungi, were more strongly correlated at the richness and regularity dimensions compared with divergence dimension. Further analyses revealed that these observed correlation patterns align with variations in soil total phosphorus content, a key factor influencing both plant and microbial phylogenetic diversity at richness and regularity dimensions. Together, our study demonstrated the necessity of using a multi‐dimensional approach to advance our understanding of the complex relationships between plant and soil microbial biodiversity. [ABSTRACT FROM AUTHOR]

• We applied 5-aminolevulinic acid (5-ALA) or thidiazuron (TDZ) to litchi preharvest. • 5-ALA increased fruit weight, and anthocyanin, phenolic, and antioxidant contents. • TDZ reduced anthocyanin content but did not significantly alter antioxidant levels. • 5-ALA and TDZ treatment increased harvest browning index and relative leakage rate. • Preharvest colour promotion by 5-ALA was optimal for postharvest litchi storage. Litchi (Litchi chinensis Sonn. cv. 'Feizixiao') has a high market value. However, its value declines during postharvest storage because its quality deteriorates, and its pericarp turns brown. Therefore, safe and effective ways of improving litchi quality and inhibiting postharvest browning are required. In this study, 5-aminolaevulinic acid (5-ALA) and thidiazuron (TDZ) were applied to litchi fruit before harvest to determine their relative effects on litchi colour and postharvest storage characteristics. The results showed that preharvest 5-ALA application significantly increased postharvest fruit weight, anthocyanins, total phenol, vitamin C and antioxidant activity relative to those in the untreated fruits. Compared with the control, TDZ significantly increased fruit weight but inhibited anthocyanin accumulation and did not significantly alter antioxidant activity. Both preharvest treatments significantly reduced the browning index, the relative leakage rate and polyphenol oxidase activity after 6 d of storage. A membership function analysis indicated that preharvest 5-ALA application was the most beneficial for postharvest storage whereas TDZ treatment was relatively less effective. Preharvest colour promotion was preferable for improving litchi quality and inhibiting postharvest browning. [ABSTRACT FROM AUTHOR]

Predicting which nonnative species become invasive is critical for their successful management, and Charles Darwin provided predictions based on species' relatedness. However, Darwin provided two opposing predictions about the relatedness of introduced nonnatives to indigenous species. First, environmental fit is the dominant factor determining invader success; thus, we should expect that invasive species are closely related to local native residents. Alternatively, if competition is important, we should expect successful invaders are distantly related to the native residents. These opposing expectations are referred to as Darwin's naturalization conundrum. The results of studies that examine nonnative species relatedness to natives are largely inconsistent. This inconsistency arises from the fact that studies occur at different spatial and temporal scales, and at different stages of invasion, and so implicitly examine different mechanisms. Further, while species have evolved ecological differences, the mode and tempo of evolution can affect species' differences, complicating the predictions from simple hypotheses. We outline unanswered questions and provide guidelines for collecting the data required to test competing hypotheses. [ABSTRACT FROM AUTHOR]

Purpose: Nitrogen (N) deposition and increased precipitation were widely reported to promote plant productivity in terrestrial ecosystems. However, few studies have explored the effects of historical resource supplements on plant communities (legacy effects). Methods: Based on a field experiment, we examined the legacy effects of N deposition and increased precipitation on plant productivity in a semi-arid steppe after the cessation of 13-year N and water addition. Results: We found historical N and water addition generally had positive effects on plant productivity even after the treatments were ceased. However, such legacy effects showed strong inter-annual variation, and the positive effects of historical N and water addition on productivity were stronger in a wet year (i.e., 2019) than in an extreme drought year (i.e., 2018). Although N availability decreased rapidly, the positive effect of historical N input persisted after 2 years of cessation largely due to the maintenance of the enhanced community plant stature (CWMstature) through the increased stature of all functional groups. Moreover, the dominance of tall grasses persisted in water added plots largely contributed to the increased productivity after the historical N and water addition. Conclusions: Our study highlights the importance of plant traits and community compositions in regulating the short-term legacy effects of historical N and water input on community productivity. The positive N and water legacy effects on productivity would both last for long given the substantially changed species compositions. Long-term observation is needed for further validation of these legacy effects because of their great year-to-year variability. [ABSTRACT FROM AUTHOR]

Plant microbiomes are known to influence host fitness and ecosystem functioning, but mechanisms regulating their structure are poorly understood.Here, we explored the assembly mechanisms of leaf epiphytic and endophytic bacterial communities using a subtropical forest biodiversity experiment.Both epiphytic and endophytic bacterial diversity increased as host tree diversity increased. However, the increased epiphytic diversity in more diverse forests was driven by greater epiphytic diversity (i.e. greater α‐diversity) on individual trees, whereas the increased endophytic diversity in more diverse forests was driven by greater dissimilarity in endophytic composition (i.e. greater β‐diversity) among trees. Mechanistically, responses of epiphytes to changes in host diversity were consistent with mass effects, whereas responses of endophytes were consistent with species sorting.Synthesis. These results provided novel experimental evidence that biodiversity declines of plant species will lead to biodiversity declines of plant‐associated microbiomes, but the underlying mechanism may differ between habitats on the plant host. [ABSTRACT FROM AUTHOR]

1. Human activities are greatly changing the conditions of ecosystems. One of these major changes is that more and more ecosystems are facing increasing concentrations of highly toxic heavy metals like cadmium (Cd), lead (Pb) and mercury (Hg). Previous studies have shown this type of pollution may be associated with the loss of biodiversity, leaving some pollution-tolerant species to dominate the polluted ecosystems. To date, however, little is known about the extent to which the pollution caused by these toxins may affect the relationship between biodiversity and ecosystem function. 2. In this study, we aimed to assess the role of Cd pollution in determining biodiversity–productivity relationships in aquatic ecosystems, by using data from a laboratory microcosm experiment that tested 110 algal communities with three levels of Cd pollution. 3. Our results showed that the productivities of algal communities growing in non-Cd-polluted media did not significantly increase with increasing species richness, and this pattern did not change over time. In contrast, significantly positive biodiversity–productivity relationships were consistently found in algal communities growing in Cd-polluted media. 4. We revealed that the putative facilitation among algal species in response to Cd pollution was the main driver of the observed significantly positive biodiversity–productivity relationships. Most importantly, we found that not only Cd-tolerant algal species but also Cd-sensitive algal species were able to dominate Cd-polluted polycultures and contribute to the increased productivities of these polycultures. 5. Synthesis and applications. Collectively, our results provide the first explicit experimental evidence that Cd pollution can trigger a positive biodiversity–productivity relationship. We identify two profound implications: (i) conservation of biodiversity in all environments may reduce the future impacts of increasing environmental stresses (like Cd pollution) on ecosystem function (such as primary productivity); (ii) one possible approach to maintain or improve algal primary productivity in a polluted aquatic ecosystem may be to construct some suitable diverse algal assemblages that include not only pollution-tolerant species but also pollution-sensitive ones. [ABSTRACT FROM AUTHOR]

Spinel-type ternary LiMn2O4 oxide precursor was synthesized by direct hydrothermal synthesis of Mn(NO3)2, LiOH, and H2O2 at 383 K for 8 h, a better technique for controlling the nanocrystalline structure with well-defined pore size distribution and high surface area than the traditional solid state reaction method. The final low-dimensional MnO2 nanorod ion-sieve with a lithium ion selective adsorption property was further prepared by an acid treatment process to completely extract lithium ions from the Li–Mn–O lattice. The effects of hydrothermal reaction conditions on the nanostructure, chemical stability, and ion-exchange property of the LiMn2O4 precursor and MnO2 ion-sieve were systematically examined via powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected-area electron diffraction (SAED), and lithium ion selective adsorption measurements. The results show that this new kind of low-dimensional MnO2 nanorod can be used for lithium extraction from aqueous environments, including brine, seawater, and waste water. [ABSTRACT FROM AUTHOR]

Plant community may provide products and services to humans. However, patterns and drivers of community stability along a precipitation gradient remain unclear. A regional‐scale transect survey was conducted over a 3‐year period from 2013 to 2015, along a precipitation gradient from 275 to 555 mm and spanning 440 km in length from west to east in a temperate semiarid grassland of northern China, a central part of the Eurasian steppe. Our study provided regional‐scale evidence that the community stability increased with increasing precipitation in the semiarid ecosystem. The patterns of community stability along a precipitation gradient were ascribed to community composition and community dynamics, such as species richness and species asynchrony, rather than the abiotic effect of precipitation. Species richness regulated the temporal mean (μ) of aboveground net primary productivity (ANPP), while species asynchrony regulated the temporal standard deviation (σ) of ANPP, which in turn contributed to community stability. Our findings highlight the crucial role of community composition and community dynamics in regulating community stability under climate change. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the roots of Swietenia macrophylla yielded one new pharagmalin-type limonoid named 2-dehydroxyl-swietephragmin C (1) and one new xanthone, 1,5-dihydroxy-6-methoxy-6′,6′-dimethyl-2H-pyrano[2′,3′:3,2]xanthone (2), in addition to three known compounds. The structures of the new compounds were unambiguously determined by comprehensive spectroscopic methods (NMR, UV, IR, MS), as well as by comparison with the reported data in the literature. Xanthones were reported from Swietenia genus for the first time. [ABSTRACT FROM AUTHOR]

Winter snowfall is an important water source for plants during summer in semiarid regions. Snow, rain, soil water, and plant water were sampled for hydrogen and oxygen stable isotopes analyses under control and increased snowfall conditions in the temperate steppe of Inner Mongolia, China. Our study showed that the snowfall contribution to plant water uptake continued throughout the growing season and was detectable even in the late growing season. Snowfall versus rainfall accounted for 30% and 70%, respectively, of the water source for plants, on the basis of hydrogen stable isotope signature (δD) analysis, and accounted for 12% and 88%, respectively, on the basis of oxygen stable isotope signature (δ18O) analysis. Water use partitioning between topsoil and subsoil was found among species with different rooting depths. Increased snowfall weakened complementarity of plant water use during summer. Our study provides insights into the relationships between precipitation regimes and species interactions in semiarid regions. [ABSTRACT FROM AUTHOR]

This study investigated the desuckering effect of a 2:1 mixture of KH 2 PO 4 (KDP) and paclobutrazol (PBZ) and its influence on banana mother plant growth, fruit yield, and quality. The mixed reagent was injected into suckers sprouting from 5-month-old banana ( Musa paradisiaca AA) plants after removing the above-ground part of the suckers. Compared to control plants, treatment with the KDP/PBZ mixture significantly reduced superoxide dismutase, peroxidase, and catalase activities but increased malondialdehyde content at sucker growth points and in adjacent tissue after 1 d. There was evidence of damage to the cellular structure at sucker growth points after 2 d of treatment, with an increase in intercellular space as well as rupturing and death of most cells. All suckers died 3 d later, resulting in a mortality rate of up to 100%, and there was no subsequent regrowth of the dead suckers; indicating that a single application of the KDP/PBZ reagent is a viable desuckering practice. Relative to the control, the treatment of suckers also indirectly increased the height and stem diameter of mother plants, which was associated with increased fruit yield (yield per plant, weight per hand, weight per fruit, transverse and longitudinal diameters of fruit fingers) and enhanced nutritional quality of the fruits (edible fraction, soluble solid, titratable acidity, vitamin C, and moisture content). These results indicate that a 2:1 KDP/PBZ mixture can effectively remove banana suckers while improving fruit yield and the quality of the mother plant. The proposed desuckering practice can help to address challenges associated with banana production such as difficulties in desuckering and preventing sucker regrowth, minimizing fertilizer waste, and high costs. [ABSTRACT FROM AUTHOR]

Abstract: Although much research has explored changes in ecosystem functions associated with global environmental changes, the mechanistic pathways behind the observed changes remain poorly understood. Using an 11‐year experiment that increased growing season precipitation and nitrogen deposition in a temperate steppe, we explored the relative importance of direct and indirect environmental change effects on plant primary productivity. We show that increases in water and nitrogen availability influenced plant productivity via both direct and indirect pathways. While both treatments stimulated plant productivity, changes in plant productivity cannot be explained by observed changes in species or phylogenetic diversity. Instead, the indirect effects of water and nitrogen addition were through their positive effects on plant functional diversity. Importantly, while the increase in one component of functional diversity (community‐level weighted mean of plant stature) resulted in increased productivity, the increase in another component of functional diversity (functional dispersion) resulted in decreased productivity. Synthesis. Our study provides the first evidence for the opposite effects of community‐weighted means and functional dispersion of plant functional traits on grassland productivity and highlights the importance of both traits of dominant species and trait distribution among species in modulating the effects of global changes on ecosystem functions. [ABSTRACT FROM AUTHOR]

Cyclic wave loading on geotube dams creates a cyclic flow in seams between geotubes regime distinct from the uni-directional flow that has been previously studied. A new laboratory apparatus was used to investigate the effects of hydraulic conditions on the core sand of geotube dams with seams between tubes. With this apparatus, a series of tests was conducted. Various maximum pressure heads (0.25, 0.3, 0.35, and 0.4 m), periods of cyclic wave loading (6, 7, 8, and 10 s) and particle porosities (34%, 35%, 40%, and 45%) were used in this test series. In the test series, the erosion development process of sand was analyzed. The results also indicate that the sand in the dam core can still perform satisfactorily after being scoured into the seam and extending a certain length. This critical length was found to be a function of the sand porosity, cycle period and maximum pressure head. [ABSTRACT FROM AUTHOR]

Litchi chinensis Sonn. cv. ‘Feizixiao’ is commonly cultivated in orchards in Hainan Island of tropical China; however, its commodity value was reduced due to the non-synchronized pericarp coloration and low aril nutritional quality. 5-Aminolevulinic acid (5-ALA), a key precursor in the biosynthesis of porphyrin compounds, is known to be an effective plant growth regulator for improving fruit coloration and nutritive quality. In this study, 5-ALA solution was exogenously sprayed at concentrations of 80, 100, 120, 140, and 160 mg L −1 on the fruit peel of ‘Feizixiao’ litchi at 45 days after full bloom. Fruit growth, coloration and nutritive quality were determined. The treatment with 5-ALA at 80 mg L −1 maintained the vitamin C content of the aril at a higher level than that of the control. The application of 5-ALA significantly increased fruit length and diameter compared with that of the control, but there was no significant effect on the titratable acid content. At 20 days after 5-ALA treatment, anthocyanin contents of the pericarp were significantly higher and the hue angle (h°) was significantly lower than those of the control. Redundancy analysis showed that 5-ALA improved the skin color of ‘Feizixiao’ litchi by promoting anthocyanin accumulation, but not chlorophyll degradation, in the pericarp during the time of harvest. This study showed that 5-ALA significantly improved the skin color at harvest time and fruit quality by promoting the growth of fruit, delaying the degradation of soluble solids, increasing the edible rate, and shortening the interval of aril development and skin coloration. [ABSTRACT FROM AUTHOR]

A new carbazole alkaloid, claulansine K (1), together with six known carbazole alkaloids (2–7), was isolated from the peels of Clausena lansium (Lour.) Skeels. The new compound was elucidated using a combination of 1D and 2D NMR (HMQC, HMBC, COSY, and ROESY) techniques, and HR-EI-MS analyses. Compound 1 showed in vitro α-glucosidase inhibitory activity with the IC50 value of 0.11 mM. Compound 2 exhibited moderate antibacterial activity against Staphylococcus aureus with the diameter of inhibition zone of 14.2 mm. [ABSTRACT FROM AUTHOR]

• A two-way coupled method was used of 166.6 MHz superconducting coupler. • The two-way coupled method is electromagnetic-fluid-thermal coupled method. The improved design reduces the risk of quench, while reducing heat leakage. Five 166.6 MHz beta = 1 quarter-wave resonator (QWR) superconducting cavities (SC) have been chosen for the High Energy Photon Source (HEPS), a 6 GeV kilometer-scale diffraction-limited storage light source to be built in Beijing suburb. Each cavity is equipped with one high power input coupler to deliver over 180 kW RF power in continuous mode (cw). Overheating and the result in excessive heat load, even quench were observed during the horizontal test of the first proof-of principle (PoP) cavity. To find the overheating reason, a dedicated two-way coupled electromagnetic-fluid-thermal simulation of the helium gas-cooled coupler was carried out by Ansys solver. This paper presents some key parameters of the coupler calculated by the two-way coupled electromagnetic-fluid-thermal numerical simulation and the accuracy of the simulation was proved by comparing with the horizontal test results. Based on the electromagnetic-fluid-thermal coupling analysis, this paper takes into account the inlet gas temperature and flow rate on the temperature distribution, electromagnetic loss distribution, and 4.2 K heat load of the coupler. Furthermore, the occurrence conditions of overheating and quench are explored and some improvement suggestions of the coupler structure are given. [ABSTRACT FROM AUTHOR]

A phytochemical investigation of the roots of Swietenia macrophylla led to the isolation of seven polyacetylenes, including five new compounds (1–5) and two known ones (6–7). Their structures were elucidated by extensive spectroscopic analysis and detailed comparison with reported data. All the isolates were tested for their cytotoxicity against the human hepatocellular carcinoma cell line BEL-7402, human myeloid leukemia cell line K562, and human gastric carcinoma cell line SGC-7901. Compounds 1 and 6 showed moderate cytotoxicity against the above three human cancer cell lines with IC50 values ranging from 14.3 to 45.4 μM. Compound 4 displayed cytotoxicity against the K562 and SGC-7901 cancer cell lines with IC50 values of 26.2 ± 0.4 and 21.9 ± 0.3 μM, respectively. [ABSTRACT FROM AUTHOR]