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Human activities have profoundly altered the Earth's phosphorus (P) cycling process and its associated microbial communities, yet their global distribution pattern and response to human influences remain unclear. Here, we estimated the abundances of P‐cycling genes from 3321 global soil metagenomic samples and mapped the global distribution of five key P‐cycling processes, that is, organic phosphoester hydrolysis, inorganic phosphorus solubilization, two‐component system, phosphotransferase system, and transporters. Structural equation modeling and random forest analysis were employed to assess the impact of anthropogenic and environmental factors on the abundance of P‐cycling genes. Our findings suggest that although less significant than the climate and soil profile, human‐related factors, such as economic activities and population, are important drivers for the variations in P‐cycling gene abundance. Notably, the gene abundances were increased parallel to the extent of human intervention, but generally at low and moderate levels of human activities. Furthermore, we identified critical genera, such as Pseudomonas and Lysobacter, which were sensitive to the changes in human activities. This study provides insights into the responses of P‐cycling microbes to human activities at a global scale, enhancing our understanding of soil microbial P cycling and underscoring the importance of sustainable human activities in the Earth's biogeochemical cycle. [ABSTRACT FROM AUTHOR]

Most existing diagnostic models are developed to detect whether students have mastered a set of skills of interest, but few have focused on identifying what scientific misconceptions students possess. This article developed a general dual‐purpose model for simultaneously estimating students' overall ability and the presence and absence of misconceptions. The expectation‐maximization algorithm was developed to estimate the model parameters. A simulation study was conducted to evaluate to what extent the parameters can be accurately recovered under varied conditions. A set of real data in science education was also analyzed to examine the viability of the proposed model in practice. [ABSTRACT FROM AUTHOR]

The effect of structure and properties of polyacrylonitrile (PAN) fibers during thermal oxidative stabilization (TOS) stage (especially high‐temperature TOS stage at 270–300°C) on the skin‐core structure of carbonized fibers was studied. The work clarified the reasons for selecting the highest TOS temperature, and also determined the optimal TOS temperature range of obtaining structurally stable carbonized fibers. The changes of chemical groups were quantitatively calculated by a combination of peak‐fitting and second‐order derivative methods. The results showed that the cyclization was dominant in the early TOS stage, oxidation reaction mainly occurred in the post‐TOS stage, and crosslinking structure significantly increased after 250°C. In the high‐temperature TOS stage, cyclization reaction was basically completed, the growth rate of oxygen content slowed down, and dehydrogenation index continued to increase. The microstructure observation found that the grooves on the fiber surface were gradually smooth after low‐temperature and high‐temperature carbonization. The radial structure of A285‐1350 and A300‐1350 fibers have obvious heterogeneity, and diameter dropped below 5 μm. Therefore, carbonized fibers have obvious structural defects when the TOS temperature is above 285°C. The TOS temperature between 200 and 285°C is more conducive to obtain structurally stable carbonized fibers. [ABSTRACT FROM AUTHOR]

Vulnerabilities in the source code of the software are critical issues in the realm of software engineering. Coping with vulnerabilities in software source code is becoming more challenging due to several aspects such as complexity and volume. Deep learning has gained popularity throughout the years as a means of addressing such issues. This paper proposes an evaluation of vulnerability detection performance on source code representations and evaluates how machine learning (ML) strategies can improve them. The structure of our experiment consists of three deep neural networks (DNNs) in conjunction with five different source code representations: abstract syntax trees (ASTs), code gadgets (CGs), semantics‐based vulnerability candidates (SeVCs), lexed code representations (LCRs), and composite code representations (CCRs). Experimental results show that employing different ML strategies in conjunction with the base model structure influences the performance results to a varying degree. However, ML‐based techniques suffer from poor performance on class imbalance handling and dimensionality reduction when used in conjunction with source code representations. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the current charging load forecasting accuracy is not high, it is difficult to simulate the actual charging load distribution of Electric Vehicles (EVs), and it is impossible to reasonably predict the future load, a charging load forecasting model based on Sparrow Search Algorithm (SSA) improved Random Forest Regression (RFR) is proposed. The SSA is used to enhance the ability of global optimization and local exploration. Combined with the advantages of the RFR model, such as low generalization error, fast convergence speed, and few adjustment parameters, the SSA was used to optimize the parameters of the decision tree number and the number of split nodes in the RFR, and the optimal value of the parameters is obtained, so as to obtain the optimal performance of the RFR. Firstly, based on the concept of travel chain and conditional probability distribution, the user's travel habits are described. Monte Carlo simulation method was used to simulate the driving, parking, and charging behaviours of a large number of EVs in different regions, so as to obtain the charging load of EVs in different regions. Then, a charging load forecasting model based on SSA improved RFR is established. Monte Carlo simulation results are used as sample data to predict the charging load of EVs in different regions. Finally, taking a certain area as an example, the experimental results show that the charging load prediction model based on Sparrow Search Algorithm improved Random Forest Regression (SSA‐RFR) can accurately predict the charging load of EVs in different regions, and the charging load of different regional types is obviously different. Compared with the RFR model and other literature models, the SSA‐RFR model has better prediction accuracy, which verifies the feasibility and superiority of SSA‐RFR model in EVs charging load prediction. [ABSTRACT FROM AUTHOR]

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]

In this brief, a type of novel fully distributed adaptive protocols is designed for achieving leader‐follower multi‐agents tracking. The design procedure constitutes three steps. First, a local observer is constructed for each agent (including the leader) in virtue of its own inputs and outputs, aiming to estimating of that agent's state. Second, to propagate the estimate of the leader from target followers to all the followers, a distributed adaptive estimator is then proposed, via embedding with time‐varying coupling weights. At last, an elegant controller is designed for each follower based on the estimate of its own state and the estimate of the leader's state. The rigorous convergence analysis is provided. Finally, the simulation results validate the effectiveness of the proposed protocols. [ABSTRACT FROM AUTHOR]

Biodiversity is known to affect ecosystem resistance and have implications for the maintenance of ecosystem functions and services under climate change. Compared to numbers of studies focusing on above‐ground vegetation, the response of below‐ground communities to abiotic stresses along plant diversity gradients is often ignored and is considered an important knowledge gap in ecosystem ecology. Here we conducted an integrative research to evaluate the resistance of plant biomass, and soil microbial communities and associated functional profiles to drought under varying plant diversity.We carried out a 3‐year manipulation experiment by factorially controlling plant diversity gradient (1, 2, 4 and 8 species richness) and soil moisture treatment (drought and non‐drought), and investigated the responses of plant biomass, soil bacterial and fungal diversity and community composition, soil glomalin, and five key soil enzymes.We found that plant diversity significantly improved the resistance of soil fungal communities and microbial functional profiles characterized by soil glomalin and five key enzymes, which was partly driven by the availability and accessibility of soil resources (e.g. soil moisture and organic matter) mediated by plant diversity. Furthermore, our results indicated that the enhanced resistance of fungal communities was consistent with ecological insurance theory that diverse fungal communities at high plant diversity had a higher probability of containing taxa that adapt to drought.Synthesis. Our study provides novel empirical insights into the mechanism underlying the regulatory effect of plant diversity on resistance of above‐ground vegetation and below‐ground biota to drought, with implications for understanding ecosystem response to climate change and improving biodiversity conservation practices. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile precursor was pretreated under nitrogen to study the effect of the extent of cyclization of pretreated fibers on the chemical structure, crystal structure and skin‐core structure of thermal oxidative stabilization (TOS) fibers. Based on the FTIR spectra, the cyclization degree of pretreated fibers was quantitatively calculated by a combination of peak‐fitting and second‐derivative operations. Combining the results of wide‐angle X‐ray diffraction, Raman spectroscopy and scanning electron microscope analysis, pretreatment was beneficial to increase the cyclized structure of TOS fibers, but inhibited the oxidation reactions in the TOS process. As the increase of cyclization degree of pretreated fibers, the oxygen content and crystal size of TOS fibers decreased and the crystal interplanar spacing increased; in the skin layer of TOS fibers, the ID/IG ratio increased and brittle fracture area decreased. When the cyclization degree of pretreated fibers was in the range of 10%–35%, the skin‐core structure of TOS fibers was weakened, which demonstrated that proper pretreatment before TOS process can improve the skin‐core structure. [ABSTRACT FROM AUTHOR]

Soil microbial communities, key players of many crucial ecosystem functions, are susceptible to environmental disturbances, which might cause the loss of microbial diversity and functions. However, few ecological concepts and practices have been developed for rescuing stressed soil microbial communities. Here, we manipulated an experiment with or without arbuscular mycorrhizal fungi (AMF) inoculation and at three levels (one, three and six species) of plant diversity to disentangle how the AMF and vegetation rescue soil nitrogen (N) ‐cycling microbial loop from simulated degraded soil ecosystem. Our results showed that AMF inoculation improved the restoration of soil N‐cycling microbial communities. This improved restoration was related to the role of AMF in enhancing interactions within the N‐cycling microbial loop. Furthermore, increased plant diversity strengthened the role of AMF in rescuing N‐cycling microbial communities. Our findings provide novel insights into the roles of AMF and plant diversity in facilitating the rescue of microbial communities in degraded terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Observational and experimental evidence has revealed the functional importance of microbial diversity. However, the effects of microbial diversity loss on ecosystem functions are not consistent across studies, which are probably tempered by microbial functional redundancy, specific taxa and functions evaluated. Here we conducted diversity manipulation experiments in two independent soils with distinct prokaryotic communities, and investigated how the initial community traits (e.g., distinct functional redundancy and taxonomic composition) modulate the contribution of prokaryotic diversity loss and composition shift to eight ecosystem functions related to soil nutrient cycling. We found that diversity loss impaired three functions (potential nitrification rate, N2‐fixation activity and phosphatase) and multifunctionality only in the communities with low functional redundancy, but all examined functions were unaffected in the communities with high functional redundancy. All significantly affected functions belonged to specialized functions, while the broad function (soil basal respiration) was unaffected. Moreover, prokaryotic composition explained more functional variation than diversity, which was ascribed to the crucial role of specific taxa that influence particular functions. Taken together, this study provides empirical evidence for identifying the mechanism underlying the ecosystem response to changes in microbial community, with implications for improving the prediction of ecosystem process models and managing microbial communities to promote ecosystem services. [ABSTRACT FROM AUTHOR]

The effects of chemical and physical structural evolution of polyacrylonitrile (PAN)‐based carbon fibers precursor during thermal oxidative stabilization (TOS) on the mechanical properties of stabilized fibers were systematically studied. The results of Fourier transform infrared spectroscopy, wide‐angle X‐ray diffraction, and density gradient column showed that the PAN fibers treated with high temperature and for long time have higher extent of cyclization, oxygen content, and crosslinking content. The crystallinity and crystallite size decreased with the increase of TOS time and temperature, whereas the bulk density of the stabilized fibers increased. The mechanical property results indicated that the decrease in tensile strength was inseparable from the formation of the cyclic structure and the amorphization transition of the crystal structure. The fibers have better structural stability when the extent of cyclization was 80–83%, the crystallinity was 34–45%, and the bulk density of stabilized fibers was 1.33–1.35 g/cm3, but exceeding these ranges, a serious skin‐core structure appeared. [ABSTRACT FROM AUTHOR]

Although diazotrophs are major participants in biological nitrogen fixation (BNF) processes, the variations in community structure and assembly processes in response to long‐term fertilization with different fertilizer application are still ambiguous, especially under various doses with balance or not. Using nifH amplicon sequencing, we investigated the soil diazotrophic communities in a paddy field which received 20‐year fertilization including control (CK), balanced fertilization (three doses of nitrogen (N), phosphorus (P), and potassium (K) at same ratio (NPK, 2(NPK), and 3(NPK)), unbalanced fertilization (three ratios, (2 N)PK, N(2P)K, and NP(2K)), and manure (M). Our results showed that the diazotrophic diversity increased with the long‐term fertilization, but it was tapering‐off with doses increment. However, the community dissimilarities increased with fertilizer doses. These variations were attributed to the trade‐off between the variation of soil pH and nutrients. The increasing of fertilizer doses induced the transformation of community assembly processes, which changed from mainly dominated by deterministic processes in CK, NPK, NP(2K) and M to stochastic processes in the other treatments. Our findings suggest that the long‐term fertilization, especially different fertilizer doses, strongly affect soil diazotrophic diversity, community structure, and assembly processes, which could help to improve the sustainable agricultural management in the future. [ABSTRACT FROM AUTHOR]

Summary: Microbial elevational diversity patterns have been extensively studied, but their shaping mechanisms remain to be explored. Here, we examined soil bacterial and fungal diversity and community compositions across a 3.4 km elevational gradient (consists of five elevations) on Mt. Kilimanjaro located in East Africa. Bacteria and fungi had different diversity patterns across this extensive mountain gradient—bacterial diversity had a U shaped pattern while fungal diversity monotonically decreased. Random forest analysis revealed that pH (12.61% importance) was the most important factor affecting bacterial diversity, whereas mean annual temperature (9.84% importance) had the largest impact on fungal diversity, which was consistent with results obtained from mixed‐effects model. Meanwhile, the diversity patterns and drivers of those diversity patterns differ among taxonomic groups (phyla/classes) within bacterial or fungal communities. Taken together, our study demonstrated that bacterial and fungal diversity and community composition responded differently to climate and edaphic properties along an extensive mountain gradient, and suggests that the elevational diversity patterns across microbial groups are determined by distinct environmental variables. These findings enhanced our understanding of the formation and maintenance of microbial diversity along elevation, as well as microbial responses to climate change in montane ecosystems. [ABSTRACT FROM AUTHOR]

In this paper, polymer‐dispersed liquid crystal (PDLC) films consisting of liquid crystal (LC)/monomers/indium tin oxide (ITO) nanoparticles with good near‐infrared absorption property had been fabricated, and the influence of the ITO nanoparticles modified with 3‐methacryloxypropyltrimethoxysilane (KH570) on the PDLC films was systematically studied. First, different liquid crystal content was studied to obtain PDLC films with good electro‐optical properties. And then, various weight ratio of ITO nanoparticles was added to samples. While the content of ITO nanoparticles was increased, the saturation voltage increased and the CR decreased. Though the electro‐optical properties of PDLC samples reduced with the addition ITO nanoparticles, the near‐infrared absorption property of films was enhanced. [ABSTRACT FROM AUTHOR]

Pyropia haitanensis (Bangiales, Rhodophyta), a major economically important marine crop, is also considered as an ideal research model of Rhodophyta to address several major biological questions such as sexual reproduction and adaptation to intertidal abiotic stresses. However, comparative genomic analysis to decipher the underlying molecular mechanisms is hindered by the lack of high‐quality genome information. Therefore, we integrated sequencing data from Illumina short‐read sequencing, PacBio single‐molecule sequencing and BioNano optical genome mapping. The assembled genome was approximately 53.3 Mb with an average GC% of 67.9%. The contig N50 and scaffold N50 were 510.3 kb and 5.8 Mb, respectively. Additionally, 10 superscaffolds representing 80.9% of the total assembly (42.7 Mb) were anchored and orientated to the 5 linkage groups based on markers and genetic distance; this outcome is consistent with the karyotype of five chromosomes (n = 5) based on cytological observation in P. haitanensis. Approximately 9.6% and 14.6% of the genomic region were interspersed repeat and tandem repeat elements, respectively. Based on full‐length transcriptome data generated by PacBio, 10,903 protein‐coding genes were identified. The construction of a genome‐wide phylogenetic tree demonstrated that the divergence time of P. haitanensis and Porphyra umbilicalis was ~204.4 Ma. Interspecies comparison revealed that 493 gene families were expanded and that 449 were contracted in the P. haitanensis genome compared with those in the Po. umbilicalis genome. The genome identified is of great value for further research on the genome evolution of red algae and genetic adaptation to intertidal stresses. [ABSTRACT FROM AUTHOR]

Summary: Acid rain can cause severe effects on soil biota and nutrient biogeochemical cycles in the forest ecosystem, but how plant‐symbiotic ectomycorrhizal fungi will modulate the effects remains unknown. Here, we conducted a full factorial field experiment in a Masson pine forest by simultaneously controlling the acidity of the simulated rain (pH 5.6 vs. pH 3.5) and the ectomycorrhizal fungi Pisolithus tinctorius inoculation (non‐inoculation vs. inoculation), to investigate the effects on ammonia oxidizers and denitrifiers. After 10 months, compared with the control (rain pH 5.6, and non‐inoculation), simulated acid rain (pH 3.5) reduced soil nutrient content, decreased archaeal amoA gene abundance and inhibited denitrification enzyme activity. Also, simulated acid rain altered the community compositions of all the examined functional genes (archaeal amoA, bacterial amoA, nirK, nirS and nosZ). However, inoculation with ectomycorrhizal fungi under acid rain stress recovered soil nutrient content, archaeal amoA gene abundance and denitrification enzyme activity to levels comparable to the control, suggesting that ectomycorrhizal fungi inoculation ameliorates simulated acid rain effects. Taken together, ectomycorrhizal fungi inoculation – potentially through improving soil substrate availability – could alleviate the deleterious effects of acid rain on nitrogen cycling microbes in forest soils. [ABSTRACT FROM AUTHOR]

Summary: Programmed cell death (PCD) induced by endoplasmic reticulum (ER) stress is implicated in various plant physiological processes, yet its mechanism is still elusive. An activation of caspase‐3‐like enzymatic activity was clearly demonstrated but the role of the two known plant proteases with caspase‐3‐like activity, cathepsin B and proteasome subunit PBA1, remains to be established. Both genetic downregulation and chemical inhibition were used to investigate the function of cathepsin B and PBA1 in ER‐stress‐induced PCD (ERSID). Transcript level and activity labelling of cathepsin B were used to assess activation. To study tonoplast rupture, a plant PCD feature, both confocal and electronic microscopies were used. Cathepsin B downregulation reduced reactive oxygen species (ROS) accumulation and ERSID without affecting the induction of the unfolded protein response (UPR), but downregulation of PBA1 increased UPR and ERSID. Tonoplast rupture was not altered in the cathepsin B mutant and cathepsin B activation was independent of vacuolar processing enzyme (VPE). VPE activity was independent of cathepsin B. ERSID is regulated positively by cathepsin B and negatively by PBA1, revealing a complex picture behind caspase‐3‐like activity in plants. Cathepsin B may execute its function after tonoplast rupture and works in parallel with VPE. [ABSTRACT FROM AUTHOR]

This paper focuses on the full-order state estimation problem for continuous-time Markovian jumping systems with time delay and incomplete transition probabilities. Based on the Lyapunov stability theory, an extended Wirtinger's inequality is used to value the upper bound of integral term by considering the relationship among time delay, its upper, and their difference. At the same time, an extended vector inequality is applied to deal with the accompanying fractions that contain the information of time delay. As a result, an improved stability criterion is derived, and a full-order state estimates design method is proposed. Finally, two examples are provided to illustrate the merits of the proposed method. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Lidocaine has been reported to induce apoptosis on rabbit corneal endothelial cells. However, the apoptotic effect and exact mechanism involved in cytotoxicity of lidocaine are not well-established in human corneal endothelial ( HCE) cells. In this study, we investigated the apoptosis-inducing effect of lidocaine on HCE cells in vitro. After HCE cells were treated with lidocaine at concentrations of 0.15625-10.0 g/l, the morphology and ultrastructure of the cells were observed by inverted light microscope and transmission electron microscope ( TEM). Cell viability was measured by MTT assay, and the apoptotic ratio was evaluated with flow cytometry and fluorescent microscopic counting after FITC-Annexin V/ PI and AO/ EB staining. DNA fragmentation was detected by electrophoresis, and the activation of caspases was evaluated by ELISA. In addition, changes in mitochondrial membrane potential were determined by JC-1 staining. Results suggest that lidocaine above 1.25 g/l reduced cellular viability and triggered apoptosis in HCE cells in a time- and dose-dependent manner. Diminishment of ΔΨm and the activation of caspases indicate that lidocaine-induced apoptosis was caspase dependent and may be related to mitochondrial pathway. [ABSTRACT FROM AUTHOR]

Stimulated exocytosis and endocytosis of post-synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid subtype of glutamate receptors (AMPARs) have been proposed as primary mechanisms for the expression of hippocampal CA1 long-term potentiation (LTP) and long-term depression (LTD), respectively. LTP and LTD, the two most well characterized forms of synaptic plasticity, are thought to be important for learning and memory in behaving animals. Both LTP and LTD can also be induced in the lateral amygdala (LA), a critical structure involved in fear conditioning. However, the role of AMPAR trafficking in the expression of either LTP or LTD in this structure remains unclear. In this study, we show that NMDA receptor-dependent LTP and LTD can be reliably induced at the synapses of the auditory thalamic inputs to the LA in brain slices. The expression of LTP was prevented by post-synaptic blockade of vesicle-mediated exocytosis with application of a light chain of Clostridium tetanus neurotoxin and was associated with increased cell-surface AMPAR expression. In contrast, the expression of LTD was prevented by post-synaptic application of a glutamate receptor 2-derived interference peptide, which specifically blocks the stimulated clathrin-dependent endocytosis of AMPARs, and was correlated with a reduction in plasma membrane-surface expression of AMPARs. These results strongly suggest that regulated trafficking of post-synaptic AMPARs is also involved in the expression of LTP and LTD in the LA. [ABSTRACT FROM AUTHOR]

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Variations in levels of apolipoprotein E (ApoE) have been tied to the risk and progression of Alzheimer's disease (AD). Our group has previously compared and contrasted the promoters of the mouse and human ApoE gene (APOE) promoter sequences and found notable similarities and significant differences that suggest the importance of the APOE promoter's role in the human disease. We examine here three specific single-nucleotide polymorphisms within the human APOE promoter region, specifically at -491 (A/T), -427 (T/C), and at -219 (G/T) upstream from the +1 transcription start site. The -219 and -491 polymorphic variations have significant association with instance of AD, and -491AA has significant risk even when stratified for the APOEepsilon4 allele. We also show significant effects on reporter gene expression in neuronal cell cultures, and, notably, these effects are modified by species origin of the cells. The -491 and -219 polymorphisms may have an interactive effect in addition to any independent activity. DNA-protein interactions differ between each polymorphic state. We propose SP1 and GATA as candidates for regulatory control of the -491 and -219 polymorphic sites. This work's significance lies in drawing connection among APOE promoter polymorphisms' associations with AD to functional promoter activity differences and specific changes in DNA-protein interactions in cell culture-based assays. Taken together, these results suggest that APOE expression levels are a risk factor for AD irrespective of APOEepsilon4 allele status., ((c) 2009 Wiley-Liss, Inc.)