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To solve the problem of the proportional design of cement concrete prepared by using manufactured sand instead of river sand, a new method of manufactured sand concrete mix design was proposed with the dense packing of coarse and fine aggregate. Compared with the original sieving method, the stone powder in the manufactured sand can be regarded as cementitious materials for slurry. With the proposed mix design method, there is no need to separate from the manufactured sand. This dense packing method considers the actual situation that both the manufactured sand and coarse aggregate are mechanically prepared, and all the aggregates can be unified in proportion. The composition ratio of aggregate with particle size greater than 0.075 mm is designed by the maximum density theory, and the rest of the part (below 0.075 mm) is treated as a cementitious material. As a parameter of the maximum density theory, the Fuller index of 0.45 was verified when the calculation values agreed well with the test results. With the proposed mix ratio design method, the different grades C30, C40, and C50 of manufactured sand concrete were designed. Furthermore, the properties such as workability and mechanical properties for the designed manufactured sand concrete were investigated to determine the applicability of the proposed mix design method. The test results show that the workability, uniformity, and strength of the manufactured sand concrete were better than the original mix ratio design method, which verifies the operability and reasonableness of the proposed mix ratio design method. [ABSTRACT FROM AUTHOR]

Nutrient enrichment impacts grassland plant diversity such as species richness, functional trait composition and diversity, but whether and how these changes affect ecosystem stability in the face of increasing climate extremes remains largely unknown.We quantified the direct and diversity‐mediated effects of nutrient addition (by nitrogen, phosphorus, and potassium) on the stability of above‐ground biomass production in 10 long‐term grassland experimental sites. We measured five facets of stability as the temporal invariability, resistance during and recovery after extreme dry and wet growing seasons.Leaf traits (leaf carbon, nitrogen, phosphorus, potassium, and specific leaf area) were measured under ambient and nutrient addition conditions in the field and were used to construct the leaf economic spectrum (LES). We calculated functional trait composition and diversity of LES and of single leaf traits. We quantified the contribution of intraspecific trait shifts and species replacement to change in functional trait composition as responses to nutrient addition and its implications for ecosystem stability.Nutrient addition decreased functional trait diversity and drove grassland communities to the faster end of the LES primarily through intraspecific trait shifts, suggesting that intraspecific trait shifts should be included for accurately predicting ecosystem stability. Moreover, the change in functional trait diversity of the LES in turn influenced different facets of stability. That said, these diversity‐mediated effects were overall weak and/or overwhelmed by the direct effects of nutrient addition on stability. As a result, nutrient addition did not strongly impact any of the stability facets. These results were generally consistent using individual leaf traits but the dominant pathways differed. Importantly, major influencing pathways differed using average trait values extracted from global trait databases (e.g. TRY).Synthesis. Investigating changes in multiple facets of plant diversity and their impacts on multidimensional stability under global changes such as nutrient enrichment can improve our understanding of the processes and mechanisms maintaining ecosystem stability. [ABSTRACT FROM AUTHOR]

The article explores the ontogenetic shifts in leaf biomass allocation in crop plants, focusing on the leaf mass ratio and its variations over transient timescales. The study develops a theoretical model to predict how plant-plant interactions affect leaf mass ratios in corn and soybean crops. Results show that leaf mass ratios differ between crop species and even within the same species planted in different years, highlighting the complexity of biomass allocation patterns during plant ontogeny. The research emphasizes the importance of considering plant competition and ontogenetic changes in understanding leaf mass ratio dynamics, providing insights into the mechanisms underlying contrasting empirical observations in plant ecology. [Extracted from the article]

Clarifying the effects of biodiversity on ecosystem stability in the context of global environmental change is crucial for maintaining ecosystem functions and services. Asynchronous changes between trophic levels over time (i.e. trophic community asynchrony) are expected to increase trophic mismatch and alter trophic interactions, which may consequently alter ecosystem stability. However, previous studies have often highlighted the stabilising mechanism of population asynchrony within a single trophic level, while rarely examining the mechanism of trophic community asynchrony between consumers and their food resources.In this study, we analysed the effects of population asynchrony within and between trophic levels on community stability under the disturbances of climate warming, fishery decline and de‐eutrophication, based on an 18‐year monthly monitoring dataset of 137 phytoplankton and 91 zooplankton in a subtropical lake.Our results showed that species diversity promoted community stability mainly by increasing population asynchrony both for phytoplankton and zooplankton. Trophic community asynchrony had a significant negative effect on zooplankton community stability rather than that of phytoplankton, which supports the match‐mismatch hypothesis that trophic mismatch has negative effects on consumers. Furthermore, the results of the structural equation models showed that warming and top‐down effects may simultaneously alter community stability through population dynamics processes within and between trophic levels, whereas nutrients act on community stability mainly through the processes within trophic levels. Moreover, we found that rising water temperature decreased trophic community asynchrony, which may challenge the prevailing idea that climate warming increases the trophic mismatch between primary producers and consumers.Overall, our study provides the first evidence that population and trophic community asynchrony have contrasting effects on consumer community stability, which offers a valuable insight for addressing global environmental change. [ABSTRACT FROM AUTHOR]

A dual-emission fluorescent biosensing method was developed for simultaneous determination of CaMV35S and NOS in genetically modified (GM) plants. Two designed hairpin DNA (H1, H2) sequences were used as templates to synthesize H1-AgNCs (λex = 570 nm, λem = 625 nm) and H2-AgNCs (λex = 470 nm, λem = 555 nm). By using H1-AgNCs and H2-AgNCs as dual-signal tags, combined with signal amplification strategy of magnetic separation to reduce background signal and an enzyme-free catalytic hairpin assembly (CHA) signal amplification strategy, a novel multi-target fluorescent biosensor was fabricated to detect multiple targets based on FRET between signal tags (donors) and magnetic Fe3O4 modified graphene oxide (Fe3O4@GO, acceptors). In the presence of the target NOS and CaMV35S, the hairpin structures of H1 and H2 can be opened respectively, and the exposed sequences will hybridize with the G-rich hairpin sequences HP1 and HP2 respectively, displacing the target sequences to participate in the next round of CHA cycle. Meanwhile, H1-HP1 and H2-HP2 double-stranded DNA sequences (dsDNA) were formed, resulting in the desorption of dsDNA from the surface of Fe3O4@GO due to weak π-π interaction between dsDNA and Fe3O4@GO and leading to the fluorescence recovery of AgNCs. Under optimal conditions, the linear ranges of this fluorescence sensor were 5 ~ 300 nmol L−1 for NOS and 5 ~ 200 nmol L−1 CaMV35S, and the LODs were 0.14 nmol L−1 and 0.18 nmol L−1, respectively. In addition, the fluorescence sensor has good selectivity for the detection of NOS and CaMV35S in GM soybean samples, showing the potential applications in GM screening. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to validate the efficiency of Doppler ultrasonography for predicting the innominate, subclavian, and common carotid artery stenosis. Methods: This retrospective multicenter study between 2013 and 2022 enrolled 636 patients who underwent carotid Doppler ultrasonography and subsequent digital subtraction angiography. And 58 innominate artery stenosis, 147 common carotid artery stenosis, and 154 subclavian artery stenosis were included. The peak systolic velocity at innominate, subclavian, and common carotid artery, and velocity ratios of innominate artery to common carotid artery, innominate artery to subclavian artery, and common carotid artery to internal carotid artery were measured or calculated. The threshold values were determined using receiver operating characteristic analysis. Results: The threshold values of innominate artery stenosis were peak systolic velocity >206 cm/s (sensitivity: 82.8%; specificity: 91.4%) to predict ≥50% stenosis and >285 cm/s (sensitivity: 89.2%; specificity: 94.9%) to predict ≥70% stenosis. The threshold values of common carotid artery stenosis were peak systolic velocity >175 cm/s (sensitivity: 78.2%; specificity: 91.9%) to predict ≥50% stenosis and >255 cm/s (sensitivity: 87.1%; specificity: 87.2%) to predict ≥70% stenosis. The threshold values of subclavian artery stenosis were peak systolic velocity >200 cm/s (sensitivity: 68.2%; specificity: 84.4%) to predict ≥50% stenosis and >305 cm/s (sensitivity: 57.9%; specificity: 91.4%) to predict ≥70% stenosis. Conclusions: Symptomatic patients with ultrasonic parameters of velocity at innominate artery ≥206 cm/s, velocity at common carotid artery ≥175 cm/s, or velocity at subclavian artery ≥200 cm/s need to be considered for further verification and whether revascularization is necessary. [ABSTRACT FROM AUTHOR]

Seaweed polysaccharides (SPs) obtained from seaweeds are a class of functional prebiotics. SPs can regulate glucose and lipid anomalies, affect appetite, reduce inflammation and oxidative stress, and therefore have great potential for managing metabolic syndrome (MetS). SPs are poorly digested by the human gastrointestinal tract but are available to the gut microbiota to produce metabolites and exert a series of positive effects, which may be the mechanism by which SPs render their anti-MetS effects. This article reviews the potential of SPs as prebiotics in the management of MetS-related metabolic disturbances. The structure of SPs and studies related to the process of their degradation by gut bacteria and their therapeutic effects on MetS are highlighted. In summary, this review provides new perspectives on SPs as prebiotics to prevent and treat MetS. [ABSTRACT FROM AUTHOR]

Atmosphere‐ocean dynamics in the tropics play a key role in global climate change. An abrupt cooling event that occurred between 4500 and 3900a BP, known as the 4.2 ka event, has long been believed to be linked to changes in sea surface temperatures (SSTs) associated with intensified El Niño and Southern Oscillation (ENSO) variability. However, the precise timing and amplitude of ENSO variability during the 4.2 ka event remain uncertain, largely due to the lack of resolution in records from the ENSO‐sensitive regions. Here we present a 104‐year‐long monthly resolved coral record from the South China Sea that spans from 4400 to 4300 years BP, corresponding to the onset of the 4.2 ka event. Using the Sr/Ca paleo‐thermometry, we show a significant decrease in ENSO variability during this time interval compared to the modern period. The ENSO events decrease in the frequency from one every 3.5 years during the modern era to one every 5.6 years during the onset of the 4.2 ka event, with weaker magnitude in the latter period. This reduction in ENSO variability is largely associated with an intensification of the Pacific Walker circulation. We therefore suggest that ENSO variability was a response to, not a driver of, the development of the 4.2 ka event. Plain Language Summary: Abrupt climate change occurred between 4,500 and 3,900 years ago, known as the 4.2 ka event, stands out as one of the most prominent climatic events in the Holocene and witnesses a northern hemisphere cooling and agricultural‐based civilization collapsed. A growing number of terrestrial records have shown that anomalous sea surface temperatures in the tropical oceans associated with intensified El Niño and Southern Oscillation (ENSO) variability triggered this abrupt climatic event. However, precise ENSO variability based on tropical oceanic records is still scarce, hindering our understanding of this event. Here, we evidence a significant reduction in ENSO variability during the onset of the 4.2 ka event using multiple monthly resolved coral records from the tropical oceans. This contrasts with previous studies that suggest increased ENSO variability triggers the 4.2 ka event, implying that anomalous ENSO variability may be a response to the 4.2 ka event. Key Points: Monthly resolved coral Sr/Ca record provides a century‐long evolution of El Niño and Southern Oscillation (ENSO) variability during the onset of the 4.2 ka eventThere is a significant reduction in ENSO variability during the onset of the 4.2 ka eventReduced ENSO variability during this time interval is associated with intensified Pacific Walker circulation [ABSTRACT FROM AUTHOR]

The outbreak and scale of harmful algal blooms (HABs) have been on the rise in recent years, mainly attributed to the effects of worsening seawater eutrophication and climate-change-related temperature increases. Yet, current approaches for detecting HABs fail to meet the requirements of rapid qualification and on-site quantification of the algae species and early warning of the outbreaks. Herein, an electrochemical biosensor based on In2O3/NC/Au NP nanomaterials was developed for the dynamic detection of Skeletonema costatum (S. costatum), one of the typical HABs. Specifically, the biosensor demonstrated a lower limit of detection (LOD, 671 fg/μL or 3528 cells/L) and had been confirmed to be accurate and reliable when compared to droplet digital PCR (ddPCR) and traditional microscope techniques. Moreover, for actual sample analysis, the concentrations of S. costatum were determined as 3.8 × 103 to 2.1 × 105 cells/L by the biosensor, which demonstrated a lower risk of S. costatum bloom outbreak in the sampling region and was consistent with the standard survey method. Therefore, the biosensor has great potential in the early stage qualitative analysis and on-site quantification of S. costatum and serves as an ideal warning technology of HAB outbreaks. [ABSTRACT FROM AUTHOR]

Hexanucleotide repeat expansion in the C9ORF72 gene is the most frequent inherited cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The expansion results in multiple dipeptide repeat proteins, among which arginine-rich poly-GR proteins are highly toxic to neurons and decrease the rate of protein synthesis. We investigated whether the effect on protein synthesis contributes to neuronal dysfunction and degeneration. We found that the expression of poly-GR proteins inhibited global translation by perturbing translation elongation. In iPSC-differentiated neurons, the translation of transcripts with relatively slow elongation rates was further slowed, and stalled, by poly-GR. Elongation stalling increased ribosome collisions and induced a ribotoxic stress response (RSR) mediated by ZAKα that increased the phosphorylation of the kinase p38 and promoted cell death. Knockdown of ZAKα or pharmacological inhibition of p38 ameliorated poly-GR–induced toxicity and improved the survival of iPSC–derived neurons from patients with C9ORF72-ALS/FTD. Our findings suggest that targeting the RSR may be neuroprotective in patients with ALS/FTD caused by repeat expansion in C9ORF72. Editor's summary: Repeat expansions in the gene C9ORF72 frequently cause the neurodegenerative diseases ALS and frontotemporal dementia. Using neurons derived from patients, Dong et al. found that repeats of glycine-arginine (poly-GR) encoded by mutant C9ORF72 RNA stalled the translational machinery, which caused ribosomes to collide. The resulting ribotoxic stress response induced neuronal death. Blocking this response by inhibiting the kinases ZAKα or p38 MAPK increased the survival of patient-derived neurons in culture. The approach might have therapeutic potential to preserve neurons in patients. —Leslie K. Ferrarelli [ABSTRACT FROM AUTHOR]

The role of plant biodiversity in stabilizing ecosystem multifunctionality has been extensively studied; however, the impact of soil biota biodiversity on ecosystem multifunctional stability, particularly under multiple environmental changes, remains unexplored. By conducting an experiment with environmental changes (adding water and nitrogen to a long‐term grazing experiment) and an experiment without environmental changes (an undisturbed site) in semi‐arid grasslands, our research revealed that environmental changes‐induced changes in temporal stability of both above‐ and belowground multifunctionality were mainly impacted by plant and soil biota asynchrony, rather than by species diversity. Furthermore, changes in temporal stability of above‐ and belowground multifunctionality, under both experiments with and without environmental changes, were mainly associated with plant and soil biota asynchrony, respectively, suggesting that the temporal asynchrony of plant and soil biota has independent and non‐substitutable effects on multifunctional stability. Our findings emphasize the importance of considering both above‐ and belowground biodiversity or functions when evaluating the stabilizing effects of biodiversity on ecosystem functions. [ABSTRACT FROM AUTHOR]

A prominent strengthened Y2O3 stabilized t-ZrO2 (YSTZ)/MgO nanocomposite coating is achieved by the plasma electrolytic oxidation (PEO) process and in-situ synthesized YSTZ reinforced phase with a quantitative control approach. The idea of activating double slip systemic semi-coherent interface dislocations in YSTZ/MgO nanocomposite coating to realize crack self-healing is proposed. High dislocation densities are associated with {101} < 101> YSTZ slip and {111} < 101> MgO slip system to coordinate interfacial deformation to stop crack initiation and propagation. This crack propagation path can absorb more fracture energy, providing more opportunities for crack deflection and bridge, which closes crack and realizes crack self-healing. This paper reveals semi-coherent interface dislocation of double slip systems in nanocomposite coating stop crack initiation and propagation is proposed to realize crack self-healing. [ABSTRACT FROM AUTHOR]

Cytokinin (CK) is an important hormone that regulates cell differentiation. The CK content in plants is regulated by cytokinin oxidase (CKX), an important enzyme that participates in hormone-regulated pathways. Additionally, CKXs comprise a large family of enzymes, but little information exists on the CKXs in potato (Solanum tuberosum). In this study, nine CKXs were identified in the potato genome and named StCKX01-09, according to their order on the linkage groups (LGs). They belong to six subfamilies, and the members within the respective subfamilies had similar motifs, a similar gene structure, and similar cis-acting elements. Additionally, the CKXs from four other species, including Arabidopsis, rice (Oryza sativa), soybean (Glycine max), and maize (Zea mays), were also divided into six subfamilies, while members within each subfamily had similar types of motifs. Moreover, the potato StCKXs were shown to influence plant hormones and stress-related factors. StCKXs were collinear, with one CKX in Arabidopsis and five CKXs in Glycine max. Quantitative real-time PCR (qRT-PCR) revealed tissue-specific expression patterns in the potato seedlings and changes in the expression levels in response to stress. Furthermore, the cytokinin content and CKX enzyme activity were shown to be regulated by StCKXs. This study provides detailed information that can help future endeavors in the molecular breeding of potato (Solanum tuberosum). [ABSTRACT FROM AUTHOR]

H1N1 influenza is highly contagious and can cause zoonotic respiratory disease. Thus, early detection is essential to prevent and control its rapid spread in the population. Given the limitations of traditional detection methods in clinical laboratories, an electrochemical biosensor modified with TAPT-TP COFs/MWCNT nanomaterial (TAPT: 4,4′,4″-(1,3,5-Triazine-2,4,6-trial) trianiline; TP: 1,3,5-Triformylphloroglucinol; MWCNTs: Multiwalled carbon nanotubes), dual-probe-specific recognizer and signal amplifier was reported, which was capable of quantifying H1N1 virus complementary DNA (cDNA) from 10 fM to 1 nM (limit of detection, LOD = 1.01 fM) with distinguished selectivity and reproducibility. Furthermore, the portable device achieved a detection range of 1 fM to 1 pM and LOD of 0.17 fM, and the accuracy was confirmed by spiked recovery experiments (recovery: 98.01–101.24%). The applicability of the portable biosensing device was verified by quantifying the concentration of H1N1 virus in the nasal turbinates and lung tissue of mice, the results of which were compared with droplet PCR (ddPCR) to validate its reliability (P > 0.05) and confirm its potential application in influenza surveillance. Thus, the above biosensor can help doctors or other professionals obtain rapid and accurate monitoring results and is expected to realize the on-site diagnosis of the H1N1 influenza virus for early intervention and epidemic management. [ABSTRACT FROM AUTHOR]

Efficient biocatalytic cascade reactions play a crucial role in guiding intricate, specific and selective intracellular transformation processes. However, the catalytic activity of the enzyme cascade reaction in bulk solution was greatly impacted by the spatial morphology and inter‐enzyme distance. The programmability and addressability nature of framework nucleic acid (FNA) allows to be used as scaffold for immobilization and to direct the spatial arrangement of enzyme cascade molecules. Here, we used tetrahedral DNA framework (TDF) as nanorulers to assemble two enzymes for constructing a double‐enzyme complex, which significantly enhance the catalytic efficiency of sarcosine oxidase (SOx)/horseradish peroxidase (HRP) cascade system. We synthesized four types of TDF nanorulers capable of programming the lateral distance between enzymes from 5.67 nm to 12.33 nm. Enzymes were chemical modified by ssDNA while preserving most catalytic activity. Polyacrylamide gel electrophoresis (PAGE), transmission electron microscopy (TEM) and atomic force microscopy (AFM) were used to verify the formation of double‐enzyme complex. Four types of double‐enzyme complexes with different enzyme distance were constructed, in which TDF26(SOx+HRP) exhibited the highest relative enzyme cascade catalytic activity, ~3.11‐fold of free‐state enzyme. Importantly, all the double‐enzyme complexes demonstrate a substantial improvement in enzyme cascade catalytic activity compared to free enzymes. [ABSTRACT FROM AUTHOR]

With the explosion of digital world, the dramatically increasing data volume is expected to reach 175 ZB (1 ZB = 1012 GB) in 2025. Storing such huge global data would consume tons of resources. Fortunately, it has been found that the deoxyribonucleic acid (DNA) molecule is the most compact and durable information storage medium in the world so far. Its high coding density and long-term preservation properties make itself one of the best data storage carriers for the future. High-throughput DNA synthesis is a key technology for "DNA data storage", which encodes binary data stream (0/1) into quaternary long DNA sequences consisting of four bases (A/G/C/T). In this review, the workflow of DNA data storage and the basic methods of artificial DNA synthesis technology are outlined first. Then, the technical characteristics of different synthesis methods and the state-of-the-art of representative commercial companies, with a primary focus on silicon chip microarray-based synthesis and novel enzymatic DNA synthesis are presented. Finally, the recent status of DNA storage and new opportunities for future development in the field of high-throughput, large-scale DNA synthesis technology are summarized. [ABSTRACT FROM AUTHOR]

Biodiversity can stabilize ecological communities through biological insurance, but climate and other environmental changes may disrupt this process via simultaneous ecosystem destabilization and biodiversity loss. While changes to diversity–stability relationships (DSRs) and the underlying mechanisms have been extensively explored in terrestrial plant communities, this topic remains largely unexplored in benthic marine ecosystems that comprise diverse assemblages of producers and consumers. By analyzing two decades of kelp forest biodiversity survey data, we discovered changes in diversity, stability, and their relationships at multiple scales (biological organizational levels, spatial scales, and functional groups) that were linked with the most severe marine heatwave ever documented in the North Pacific Ocean. Moreover, changes in the strength of DSRs during/after the heatwave were more apparent among functional groups than both biological organizational levels (population vs. ecosystem levels) and spatial scales (local vs. broad scales). Specifically, the strength of DSRs decreased for fishes, increased for mobile invertebrates and understory algae, and were unchanged for sessile invertebrates during/after the heatwave. Our findings suggest that biodiversity plays a key role in stabilizing marine ecosystems, but the resilience of DSRs to adverse climate impacts primarily depends on the functional identities of ecological communities. [ABSTRACT FROM AUTHOR]

By designing stator teeth using grain-oriented sheets (GO) and other parts still with non-grain-oriented sheets (NGO), the electromagnetic performance of the interior permanent magnet synchronous machine (GO-IPMSM) can be improved greatly. As the stator core of the designed GO-IPMSM is a hybrid core that is composed of two different silicon sheets, both the electromagnetic and mechanical performances are affected by the stator joint shape between GO and NGO sheets. Meanwhile, with the adoption of GO, the torque ripple of GO-IPMSM is increased though the average torque is increased as well. For reducing the torque ripple, optimizing the rotor barrier shape is an effective way. In this paper, the piecewise linear interpolation method is employed for establishing the stator joint shape between GO and NGO sheets, and the polynomial method is proposed to establish the rotor barrier shape. Through the analysis, it can be seen that the stator joint shape plays a strong role in affecting the mechanical performance of the GO-IPMSM, while the effect on the electromagnetic performance is weak. The genetic algorithm is used to optimize the rotor barrier shape for achieving high average torque and low torque ripple. Lastly, a quick and accurate efficiency map calculation method based on the Kriging model is proposed for GO-IPMSM with less finite element method (FEM) samples are required. [ABSTRACT FROM AUTHOR]

Aim: Species–area relationships (SAR) are widely utilized for estimating the species richness and its spatial turnover across various scales. Despite the prevalent characterization of SAR using the power law in many microbial community studies, its efficacy remains unvalidated. This study aims to characterize the microbial SAR and its mechanisms in alpine grassland soils on the Qinghai‐Tibet Plateau (QTP). Location: Qinghai‐Tibet Plateau, China. Time Period: August 2014. Major Taxa Studied: Soil bacteria. Methods: Soil samples were collected from five alpine grassland sites on the QTP. Employing a nested sampling strategy at each site, soil samples were collected in plot sizes ranging from 0.5 × 0.5 m2 to 2048 × 2048 m2. Soil bacterial communities were analysed by sequencing 16S ribosomal RNA gene amplicons using an Illumina MiSeq. Results: The bacterial SAR exhibited a logarithmic power law (R2: 0.952–0.999), outperforming the power law (R2: 0.701–0.852). Consequently, the most widely adopted power law led to an overestimation of species richness by up to 15.07% in areas >256 × 256 m2, and the regional maximum theoretical richness based on Chao1 by up to 9.88%. Mechanistically, the passive sampling hypothesis was refuted through the rarefied species richness analysis, and the disproportionate effect hypothesis was rejected based on analyses of the effective numbers of species number conversions for the probability of interspecific encounters (SPIE). Notably, Pearson and multiple linear regression analyses indicated that the spatial turnover of bacterial richness was determined by the environmental heterogeneity (R2: 0.855–0.999), rather or better than environmental variables themselves, supporting the 'environment heterogeneity hypothesis'. Main Conclusions: Soil bacterial SAR in alpine grasslands exhibited a logarithmic power relationship. Spatial turnover was primarily governed by the environmental heterogeneity. In contrast, the traditional power law leads to an overestimation of soil bacterial diversity at the regional scale. [ABSTRACT FROM AUTHOR]

Simple Summary: Nemognathinae is notable for its high diversity in Meloidae, yet our knowledge about its species in China remains restricted. Here, we describe a new genus and species and report three other species as new additions to the Chinese fauna. Based on our investigation of the types, we transfer the genus Oreomeloe from Meloini to Nemognathini. Finally, we present molecular phylogenies built on multi-locus data, which corroborate the systematic placement of Sinostenoria and Longizonitis. Our findings and treatment contribute to the understanding of Chinese Nemognathinae and resolve a pending issue in the taxonomy of Nemognathinae. Despite being the most widespread blister beetle subfamily, Nemognathinae is unfairly understudied in China. In this study, a new genus and species, Sinostenoria yangi Pan, from northern China is described and illustrated. The antennae, elytra, hind wings, and claws of the new genus form a truly unique set of characteristics never observed in other genera of Nemognathini Laporte de Castelnau, 1840. Three species from China are newly recorded and illustrated: Megatrachelus sibiricus (Tauscher, 1812), Zonitomorpha dollei (Fairmaire 1889), and Stenodera djakonovi Aksentjev, 1978. The genus Oreomeloe Tan, 1981, is transferred from the tribe Meloini Gyllenhal, 1910, to Nemognathini based on an examination of the types. Aiming to test the morphology-based placement of the new genus, we conducted molecular phylogenetic analyses using two mitochondrial (COI, 16S) and three nuclear markers (28S, CAD, ITS2). The results confirm our tribal assignment of the new genus and support a clade that consists of Sinostenoriagen. n., Longizonitis Pan and Bologna, 2018, Stenoria cf. grandiceps, and Ctenopus cf. persicus. [ABSTRACT FROM AUTHOR]

Background: Synchroa medogensis, a new species of Synchroidae Lacordaire, 1859, is described and illustrated, based on a single male collected from Mêdog, Xizang, China. This new species is close to S. elongatula Nikitsky, 1999 and S. melanotoides Lewis, 1895, but could be distinguished by the elongated antennae and elytra, the apically narrowed prosternal process and the stout parameres. New information: The new information of this new species provided in this paper include: description, type information, distribution and comparison amongst S. medogensis sp. nov., S. elongatula and S. melanotoides. [ABSTRACT FROM AUTHOR]

BACKGROUND: Organophosphorus pesticides (OPs) were used in large quantities, and pesticide residues have caused different degrees of environmental pollution. Because the current laboratory detection techniques cannot meet the requirements of quickly and accurately monitoring pesticide concentration, there is an urgent need for a portable and accurate method to trace pesticide residues. This paper reports an effective electrochemical sensor composed of ZrO2@PDA electrode material and glassy carbon electrode (GCE). RESULTS: This sensor displayed optimal selectivity for dichloride among various OPs with a low limit of detection (LOD = 1.318 × 10−3 mg L−1). Wherein the accuracy and reliability of this electrochemical sensor were verified through the standard method of gas chromatography–mass spectrometry (GC–MS) (p = 0.977 > 0.05), as well as the stability and anti‐interference capabilities. In addition, the results of recovery experiments have shown that the recovery rate of the electrochemical sensor for dichlorvos ranged from 89.2% to 103.8%, with RSD less than 5%, indicating its practical application in the actual sample detection. CONCLUSIONS: Finally, the portable sensing platform for on‐site analysis of dichlorvos concentration in farmland water samples was also demonstrated with excellent results. All the results suggested that the prepared ZrO2@PDA composites could serve as a prospective microchip sensor for the on‐site detection of dichlorvos. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Drought is a major threat to alfalfa (Medicago sativa L.) production. The discovery of important alfalfa genes regulating drought response will facilitate breeding for drought‐resistant alfalfa cultivars. Here, we report a genome‐wide association study of drought resistance in alfalfa. We identified and functionally characterized an MYB‐like transcription factor gene (MsMYBH), which increases the drought resistance in alfalfa. Compared with the wild‐types, the biomass and forage quality were enhanced in MsMYBH overexpressed plants. Combined RNA‐seq, proteomics and chromatin immunoprecipitation analysis showed that MsMYBH can directly bind to the promoters of MsMCP1, MsMCP2, MsPRX1A and MsCARCAB to improve their expression. The outcomes of such interactions include better water balance, high photosynthetic efficiency and scavenge excess H2O2 in response to drought. Furthermore, an E3 ubiquitin ligase (MsWAV3) was found to induce MsMYBH degradation under long‐term drought, via the 26S proteasome pathway. Furthermore, variable‐number tandem repeats in MsMYBH promoter were characterized among a collection of germplasms, and the variation is associated with promoter activity. Collectively, our findings shed light on the functions of MsMYBH and provide a pivotal gene that could be leveraged for breeding drought‐resistant alfalfa. This discovery also offers new insights into the mechanisms of drought resistance in alfalfa. [ABSTRACT FROM AUTHOR]

Introducing nanomaterials in gas sensor applications has conspicuously improved the detection performance due to the unique nanostructures. Transition-metal dichalcogenides (TMDs) recently aroused widespread interest because of their ultrathin and layered two-dimensional nanosheet structures. The graphene-like MoS2 has good electrical, chemical, mechanical, and optical properties, making it of great interest for developing gas sensors and an exceptionally promising building block for designing novel semiconducting nanomaterials. The content of this mini-review aspires to summarize the current progress on mono/few-layered MoS2-based gas sensors and the influence of different components. Herein, we described the current progress on MoS2-based gas sensors, which encompasses the preparation and application of MoS2, and the potential improvement directions for future possibilities of expanding its applications. [ABSTRACT FROM AUTHOR]

Cr coatings with a thickness of about 19 μm were synthesized on Zr-4 cladding using plasma-enhanced arc ion plating. A Zr-Cr micro-diffusion layer was formed via Cr ion cleaning before deposition to enhance the interface bonding strength. Cr coatings exhibit an obvious columnar crystal structure with an average grain size of 1.26 μm using SEM (scanning electron microscopy) and EBSD (electron backscatter diffraction) with a small amount of nanoscale pores on the surface. A long-term aqueous test at 420 ± 3 °C, 10.3 ± 0.7 MPa and isothermal oxidation tests at 900~1300 °C in air were conducted to evaluate the Cr-coated Zr-4 cladding. All the results showed that the Cr coatings had a significant protective effect to the Zr-4 alloy. However, the corrosion deterioration mechanism is different. A gradual thinning of the Cr coating was observed in a long-term aqueous test, but a cyclic corrosion mechanism of void initiation–propagation–cracking at the oxide film interface is the main corrosion characteristic of the Cr coating in isothermal oxidation. Different corrosion models are constructed to explain the corrosion mechanism. [ABSTRACT FROM AUTHOR]

In this paper, a new multiple plasma jet tangentially mixed reactor (MPJ-TMR) is proposed. The impact of varying tangent circle diameters on the mixing process is investigated through CFD simulation. The MPJ-TMR has been preliminarily applied to high-conductive carbon black (HCCB) preparation. The results show that the MPJ-TMR with a tangent circle diameter dc/din = 0 is directed to form the "counter-flow recirculation zone", which impedes mixing between plasma jets and cold fluids. For the MPJ-TMR with a tangent circle diameter dc/din > 0, the intensity of the "counter-flow recirculation zone" weakens and disappears as the tangent circle diameter increases. The eccentric impact flow drives the fluid to spiral around the central axis. So that a spiral vortex structure is formed to enhance the mixing. Among them, the MPJ-TMR with a tangent circle diameter dc/din = 0.5 exhibits the best mixing efficiency due to its highest local circumferential velocity and axial vortex flux, resulting in good entrainment between plasma jets and cold fluids. Therefore, the MPJ-TMR with a tangent circle diameter dc/din = 0.5 is applied to prepare carbon black. The resulting products show a rich branched chain structure with over 90% of the primary particle size distributed within the range of 10–20 nm. The physicochemical indices DBP Absorption, IAN and resistivity of HCCB are very close to that of acetylene carbon black. The reactor demonstrates excellent product uniformity. [ABSTRACT FROM AUTHOR]

The abrupt onset of the COVID-19 pandemic in late 2019 significantly disrupted China's domestic agricultural production and supply chain stability. Local governments, responding to urgent circumstances, implemented various trade restrictions that profoundly affected regional economic development. This study, covering data from 2010 to 2019 across 31 provinces, investigates agricultural market integration and regional economic development. Employing a dynamic spatial panel Durbin model, it systematically analyzes the complex relationship between these variables. International trade variables related to agricultural products are then introduced to examine their "substitution effect" in promoting regional economic development through agricultural market integration. The research findings are summarized as follows: (1) disregarding international agricultural trade, a one-unit increase in the agricultural market integration index corresponds to a 0.156% rise in regional economic development. (2) In an open economy, the substitution coefficients for agricultural imports, exports, and total trade concerning market integration are −0.00097, −0.0012, and −0.0038, respectively. (3) The strength of the substitution effect from the international agricultural market to the domestic market varies regionally, with coefficients of −0.00099 and −0.00217 for the eastern and western regions, respectively. [ABSTRACT FROM AUTHOR]

When the high-voltage transmission line inspection robot (HVTIR) with gripper is pre-landing line during flight, the vibration of the landing gripper seriously affects the stability of landing line. To study the vibration characteristics of the flying HVTIR during pre-landing flight, a mass-stiffness-damping vibration model from the rotor to the landing gripper is constructed based on the D'Alembert's principle. Secondly, based on the model, a sensitivity function between the HVTIR's gripper vibration and the damping ratio, mass ratio, and natural frequency of the components is constructed using the normalization method. By this function, the HVTIR structure is quickly optimized accordingly, the maximum vibration value of the gripper is reduced by 25.72 %, and the minimum interquartile spacing of the box graph is reduced by 23.01 %. Finally, the HVTIR test system is established using MPU6050. Under different flight modes, the trend of theoretical value and experimental value are the same, and the maximum error range is not more than 26 %, and the minimum interquartile spacing of the box graph is not more than 27.01 %. The rationality of the model is proved, which also provides a basis for subsequent control. [ABSTRACT FROM AUTHOR]

Background: To determine the efficacy and safety of intravitreally injected conbercept, a vascular endothelial growth factor receptor fusion protein, for the treatment of idiopathic choroidal neovascularization (ICNV). Methods: This retrospective study analyzed outcomes in 40 patients (40 eyes) with ICNV who received intravitreal injections of conbercept 0.5 mg (0.05 ml) and were followed up for at least 12 months. All patients underwent full ophthalmic examinations, including best-corrected vision acuity (BCVA), intraocular pressure (IOP), slit-lamp examination, color fundus photography, optical coherence tomography angiography, multifocal electroretinogram, and fundus fluorescence angiography, if necessary, at baseline and after 1, 3, 6, and 12 months. BCVA, macular central retinal thickness (CRT), IOP, CNV blood flow area, thickness of the CNV-pigment epithelial detachment complex, thickness of the retinal nerve fiber layer (RNFL), and the first positive peak (P1) amplitude density in ring 1 before and after treatment were compared. Results: Mean baseline BCVA (logMAR), CRT, CNV blood flow area, and CNV-pigment epithelial detachment complex thickness were significantly lower 1, 3, 6, and 12 months after than before conbercept treatment (P < 0.05 each). IOP and baseline RNFL thickness were unaffected by conbercept treatment. P1 amplitude density was significantly higher 1, 3, 6, and 12 months after than before conbercept treatment (P < 0.05 each). None of the 40 eyes showed obvious ocular adverse reactions, such as endophthalmitis, glaucoma, cataract progression, and retinal detachment, and none of the patients experienced systemic adverse events, such as cardiovascular and cerebrovascular accidents. Conclusions: Intravitreal injection of conbercept is beneficial to eyes with ICNV, inducing the recovery of macular structure and function and improving BCVA, while not damaging the neuroretina. Intravitreal conbercept is safe and effective for the treatment of ICNV. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) piezoelectric semiconductor materials are garnering significant attention in applications such as intelligent sensing and energy harvesting due to their exceptional physical and chemical properties. Among these, molybdenum disulfide (MoS2), a 2D wide-bandgap semiconductor, exhibits piezoelectricity in odd-layered structures due to the absence of an inversion symmetry center. In this study, we present a straightforward chemical vapor deposition (CVD) technique to synthesize monolayer MoS2 on a Si/SiO2 substrate, achieving a lateral size of approximately 50 µm. Second-harmonic generation (SHG) characterization confirms the non-centrosymmetric crystal structure of the wide-bandgap MoS2, indicative of its piezoelectric properties. We successfully transferred the triangular MoS2 to a polyethylene terephthalate (PET) flexible substrate using a wet-transfer method and developed a wide-bandgap MoS2-based micro-displacement sensor employing maskless lithography and hot evaporation techniques. Our testing revealed a piezoelectric response current of 5.12 nA in the sensor under a strain of 0.003% along the armchair direction of the monolayer MoS2. Furthermore, the sensor exhibited a near-linear relationship between the piezoelectric response current and the strain within a displacement range of 40–100 µm, with a calculated response sensitivity of 1.154 µA/%. This research introduces a novel micro-displacement sensor, offering potential for advanced surface texture sensing in various applications. [ABSTRACT FROM AUTHOR]

In this paper, a new defective phononic crystal (PC) microbeam model in a thermal environment is developed with the application of modified couple stress theory (MCST). By using Hamilton's principle, the wave equation and complete boundary conditions of a heated Bernoulli–Euler microbeam are obtained. The band structures of the perfect and defective heated PC microbeams are solved by employing the transfer matrix method and supercell technology. The accuracy of the new model is validated using the finite element model, and the parametric analysis is conducted to examine the influences of size and temperature effects, as well as defect segment length, on the band structures of current microbeams. The results indicate that the size effect induces microstructure hardening, while the increase in temperature has a softening impact, decreasing the band gap frequencies. The inclusion of defect cells leads to the localization of elastic waves. These findings have significant implications for the design of microdevices, including applications in micro-energy harvesters, energy absorbers, and micro-electro-mechanical systems (MEMS). [ABSTRACT FROM AUTHOR]

Bacterial infections, increasingly resistant to common antibiotics, pose a global health challenge. Traditional diagnostics often depend on slow cell culturing, leading to empirical treatments that accelerate antibiotic resistance. We present a novel large-volume microscopy (LVM) system for rapid, point-of-care bacterial detection. This system, using low magnification (1–2×), visualizes sufficient sample volumes, eliminating the need for culture-based enrichment. Employing deep neural networks, our model demonstrates superior accuracy in detecting uropathogenic Escherichia coli compared to traditional machine learning methods. Future endeavors will focus on enriching our datasets with mixed samples and a broader spectrum of uropathogens, aiming to extend the applicability of our model to clinical samples. [ABSTRACT FROM AUTHOR]

The detection and analysis of small molecules, typically defined as molecules under 1000 Da, is of growing interest ranging from the development of small-molecule drugs and inhibitors to the sensing of toxins and biomarkers. However, due to challenges such as their small size and low mass, many biosensing technologies struggle to have the sensitivity and selectivity for the detection of small molecules. Notably, their small size limits the usage of labeled techniques that can change the properties of small-molecule analytes. Furthermore, the capability of real-time detection is highly desired for small-molecule biosensors' application in diagnostics or screening. This review highlights recent advances in label-free real-time biosensing technologies utilizing different types of transducers to meet the growing demand for small-molecule detection. [ABSTRACT FROM AUTHOR]

Questions: The minimum sampling area (minimum area) is the smallest space that reflects species composition and characteristics of a plant community. The quantitative concept of minimum area is often estimated using species–area relationships (SARs) and has become the classical foundation for managing protected areas. However, sampling designs to determine the minimum area in different forest types have not been systematically evaluated. Location: China. Methods: We used tree census data from three forest dynamic plots, each with a size of 25–60 ha, in different climatic zones in China to determine the minimum areas of woody plants and to analyze the effects of species richness and topographic heterogeneity on the minimum areas by changing sampling origin and direction. Results: We found that mainly sampling design affects the estimation of woody plant species richness and required minimum area in different forest types. The estimated size of the minimum areas required was several hectares and varied significantly with sampling origin and direction, and showed a difference of approximately 1.5–2 times in the forest plots. Topographic heterogeneity significantly affected the minimum area through changes in species composition. Conclusions: Sampling origin and direction should be considered when using SARs to estimate the minimum area and species diversity in communities. Such a comprehensive approach of sampling can contribute to a better understanding of vegetation characteristics and the minimum area required for a conservation census in heterogeneous environments. [ABSTRACT FROM AUTHOR]

A central aim of community ecology is to understand how local species diversity is shaped. Agricultural activities are reshaping and filtering soil biodiversity and communities; however, ecological processes that structure agricultural communities have often overlooked the role of the regional species pool, mainly owing to the lack of large datasets across several regions. Here, we conducted a soil survey of 941 plots of agricultural and adjacent natural ecosystems (e.g., forest, wetland, grassland, and desert) in 38 regions across diverse climatic and soil gradients to evaluate whether the regional species pool of soil microbes from adjacent natural ecosystems is important in shaping agricultural soil microbial diversity and completeness. Using a framework of multiscales community assembly, we revealed that the regional species pool was an important predictor of agricultural bacterial diversity and explained a unique variation that cannot be predicted by historical legacy, large‐scale environmental factors, and local community assembly processes. Moreover, the species pool effects were associated with microbial dormancy potential, where taxa with higher dormancy potential exhibited stronger species pool effects. Bacterial diversity in regions with higher agricultural intensity was more influenced by species pool effects than that in regions with low intensity, indicating that the maintenance of agricultural biodiversity in high‐intensity regions strongly depends on species present in the surrounding landscape. Models for community completeness indicated the positive effect of regional species pool, further implying the community unsaturation and increased potential in bacterial diversity of agricultural ecosystems. Overall, our study reveals the indubitable role of regional species pool from adjacent natural ecosystems in predicting bacterial diversity, which has useful implication for biodiversity management and conservation in agricultural systems. [ABSTRACT FROM AUTHOR]

In this paper, we present a plasma rapid heater (PRH) designed to uniformly heat methane with electric arc thermal plasma and reduce loss rate. Our model uses a simplified and detailed mechanism to analyze the rapid and intense mixing process between a plasma mainstream and circumferential cold jets of methane in a hydrogen environment. The research focuses on three areas: the plasma mainstream section, the circumferential jet mixing chamber, and the reaction chamber. We investigate the characteristics of the mainstream and explore the impact of the jet momentum ratio on the mixing process and the losses from methane heating. We explain these phenomena using Damkohler numbers to demonstrate the relationship from a time-scale perspective. The findings indicate that an increased momentum ratio improves mixing, reduces temperature and material non-uniformity, and minimizes losses from pyrolysis during methane heating. Additionally, we provide a formula for calculating the penetration depth of the jet. The examination of Damkohler numbers also suggests that the momentum ratio primarily reduces methane losses by extending the reaction time scale. This work offers guidance on extending the usage of plasma heaters and integrating them into other industry processes in the future. [ABSTRACT FROM AUTHOR]

Although epidemiological studies have evaluated the association between ambient air pollution and chronic kidney disease (CKD), the results remain mixed. To clarify the nature of the association, we conducted a comprehensive systematic review and meta‐analysis to assess the global relationship between air pollution and CKD. The Web of Science, PubMed, Embase and Cochrane Library databases systematically were searched for studies published up to July 2023 and included 32 studies that met specific criteria. The random effects model was used to derive overall risk estimates for each pollutant. The meta‐analysis estimated odds ratio (ORs) of risk for CKD were 1.42 (95% confidence interval [CI]: 1.31–1.54) for each 10 μg/m3 increase in PM2.5; 1.20 (95% CI: 1.14–1.26) for each 10 μg/m3 increase in PM10; 1.07 (95% CI: 1.05–1.09) for each 10 μg/m3 increase in NO2; 1.03 (95% CI: 1.02–1.03) for each 10 μg/m3 increase in NOX; 1.07 (95% CI: 1.01–1.12) for each 1 ppb increase in SO2; 1.03 (95% CI: 1.00–1.05) for each 0.1 ppm increase in CO. Subgroup analysis showed that this effect varied by gender ratio, age, study design, exposure assessment method, and income level. Furthermore, PM2.5, PM10, and NO2 had negative effects on CKD even within the World Health Organization‐recommended acceptable concentrations. Our results further confirmed the adverse effect of air pollution on the risk of CKD. These findings can contribute to enhance the awareness of the importance of reducing air pollution among public health officials and policymakers. [ABSTRACT FROM AUTHOR]

Ketones are well-known biomarkers of fat oxidation produced in the liver as a result of lipolysis. These biomarkers include acetoacetic acid and β-hydroxybutyric acid in the blood/urine and acetone in our breath and skin. Monitoring ketone production in the body is essential for people who use caloric intake deficit to reduce body weight or use ketogenic diets for wellness or therapeutic treatments. Current methods to monitor ketones include urine dipsticks, capillary blood monitors, and breath analyzers. However, these existing methods have certain disadvantages that preclude them from being used more widely. In this work, we introduce a novel acetone sensor device that can detect acetone levels in breath and overcome the drawbacks of existing sensing approaches. The critical element of the device is a robust sensor with the capability to measure acetone using a complementary metal oxide semiconductor (CMOS) chip and convenient data analysis from a red, green, and blue deconvolution imaging approach. The acetone sensor device demonstrated sensitivity of detection in the micromolar-concentration range, selectivity for detection of acetone in breath, and a lifetime stability of at least one month. The sensor device utility was probed with real tests on breath samples using an established blood ketone reference method. [ABSTRACT FROM AUTHOR]

The inter-particle bonding (IPB) mechanism of cold-sprayed titanium alloy during heat treatment (HT) is not clear. The interfacial microstructure and bonding characteristics at the interface of cold-sprayed Ti6Al4V after HT were studied at the micro- and nano-scale. As a result, the nanocrystallization at IPB during cold spray (CS) cannot cause obvious metallurgical bonding between Ti6Al4V particles. The average Young's modulus of CS Ti6Al4V is 57% higher than that of powder, but the average Young's modulus of HT sample decreases by 16%. The internal stress and dislocation distribution of interfacial microstructure can lead to various microstructure features and non-uniform rates of microstructure growth at deformed transition layer and IPB during HT. The nanograins at the IPB grow into micron-equiaxed grains. On the contrary, the micron martensitic laths at deformed transition layer adjacent to IPB show the characteristics of equiaxed nanograins transformation under the action of grain boundary bulges induced by dislocation entanglement. [ABSTRACT FROM AUTHOR]

Context: Forest–grassland ecotones, the transitional zones between forests and grasslands, often harbor high levels of biodiversity. According to the portfolio theory, communities with such high biodiversity should exhibit high stability in ecosystem functioning. On the contrary, the theory of 'bi-stability' or 'multistability' predicts that ecosystems exhibiting multiple states or regimes (e.g. forest and grassland) are less stable. Understanding the stability of forest–grassland ecotone has broad implications for forest management and restoration. Objectives: In this study, by quantifying landscape heterogeneity and temporal invariability of regional climatic and vegetational metrics, we aimed to reveal how landscape diversity influences the stability of ecosystem functioning in the forest–grassland ecotone. Methods: We focused on the forest–grassland ecotone in northern China (i.e. from the forest belt in the Greater Khingan Mountains to the steppe grassland in Inner Mongolia) and used remote sensing data of land cover dynamics from 1992 to 2015 to analyze the landscape diversity and ecosystem dynamics at different grain sizes. To measure the temporal stability of climatic variables and vegetational dynamics, we calculated the interannual variation of temperature (T), wind speed (WS), precipitation (P), and the net primary productivity (NPP) on the grided sampling cells at different spatial scale over the same period. Results: Our results showed that landscape diversity across this forest–grassland ecotone was positively related to the stability of T and NPP, but negatively related to that of WS and P. These opposite patterns may be explained by the differential nature of ecosystem variables, namely whether they involve transporting substance across space (WS and P) or not (T and NPP). We also found that as the spatial scale increases, the diversity-stability relationships strengthened for all three climatic variables (i.e., T, P, WS). However, the stabilizing effects of landscape diversity on NPP first increased but then decreased with increasing grain size, peaking at ~ 30 km. Conclusions: Our empirical analyses demonstrate strong, but context-dependent diversity-stability relationships, shedding light on the paradox in the stability of ecosystem functioning in the ecotone. These findings also have implications for the management of landscape resources to maintain the sustainability of forest–grassland ecotones. [ABSTRACT FROM AUTHOR]

Selective logging is one of the most prevalent land uses of forests worldwide, affecting biodiversity and ecosystem functioning. However, the effect of selective logging on the dual nature of temporal stability, and the scale dependence of this effect, remain to be elucidated. By conducting several decade‐long experiments in temperate forest ecosystems, we tested the effects of selective logging on aggregate and compositional stability at multiple spatial scales. As expected, forest ecosystem stability at larger spatial scales was enhanced both by the stability of local scales (i.e. α stability) and asynchronous dynamics among local communities (i.e. spatial asynchrony). We found that the negative effects of selective logging on both facets of forest stability propagated from local to larger spatial scales due to reduced α stability and the biological insurance effects of α diversity. However, both spatial aggregate and compositional asynchrony were not affected by selective logging. Interestingly, despite the selective logging, α diversity still provided biological insurance effects for maintaining aggregate and compositional stability. Our results imply that selective logging may destabilize the aggregate ecosystem functioning and species composition of forest ecosystems at local and larger spatial scales. To our knowledge, this study provides the first evidence of the scale dependence of aggregate and compositional stability of forest ecosystems in response to selective logging. Our findings suggest that forest management should avoid excessive selective logging and strive to protect forest diversity to safeguard the sustainability of the functioning and composition of natural forest ecosystems at multiple spatial scales. Keywords: aggregate stability, compositional stability, diversity, ecosystem functioning, spatial asynchrony, stability [ABSTRACT FROM AUTHOR]

Eutrophication usually impacts grassland biodiversity, community composition, and biomass production, but its impact on the stability of these community aspects is unclear. One challenge is that stability has many facets that can be tightly correlated (low dimensionality) or highly disparate (high dimensionality). Using standardized experiments in 55 grassland sites from a globally distributed experiment (NutNet), we quantify the effects of nutrient addition on five facets of stability (temporal invariability, resistance during dry and wet growing seasons, recovery after dry and wet growing seasons), measured on three community aspects (aboveground biomass, community composition, and species richness). Nutrient addition reduces the temporal invariability and resistance of species richness and community composition during dry and wet growing seasons, but does not affect those of biomass. Different stability measures are largely uncorrelated under both ambient and eutrophic conditions, indicating consistently high dimensionality. Harnessing the dimensionality of ecological stability provides insights for predicting grassland responses to global environmental change. Anthropogenic eutrophication is a driver of plant community shifts in many grassland ecosystems. Here, the authors use data from a globally distributed experiment to assess how nutrient addition affects multiple facets of grassland ecological stability and their correlations. [ABSTRACT FROM AUTHOR]

Plant community productivity generally increases with biodiversity, but the strength of this relationship exhibits strong empirical variation. In meta‐food‐web simulations, we addressed if the spatial overlap in plants' resource access and animal space‐use can explain such variability. We found that spatial overlap of plant resource access is a prerequisite for positive diversity–productivity relationships, but causes exploitative competition that can lead to competitive exclusion. Space‐use of herbivores causes apparent competition among plants, resulting in negative relationships. However, space‐use of larger top predators integrates sub‐food webs composed of smaller species, offsetting the negative effects of exploitative and apparent competition and leading to strongly positive diversity–productivity relationships. Overall, our results show that spatial overlap of plants' resource access and animal space‐use can greatly alter the strength and sign of such relationships. In particular, the scaling of animal space‐use effects opens new perspectives for linking landscape processes without effects on biodiversity to productivity patterns. [ABSTRACT FROM AUTHOR]

A new size-dependent axially functionally graded (AFG) micro-beam model is established with the application of a reformulated strain gradient elasticity theory (RSGET). The new micro-beam model incorporates the strain gradient, velocity gradient, and couple stress effects, and accounts for the material variation along the axial direction of the two-component functionally graded beam. The governing equations and complete boundary conditions of the AFG beam are derived based on Hamilton's principle. The correctness of the current model is verified by comparing the static behavior results of the current model and the finite element model (FEM) at the micro-scale. The influence of material inhomogeneity and size effect on the static and dynamic responses of the AFG beam is studied. The numerical results show that the static and vibration responses predicted by the newly developed model are different from those based on the classical model at the micro-scale. The new model can be applied not only in the optimization of micro acoustic wave devices but also in the design of AFG micro-sensors and micro-actuators. [ABSTRACT FROM AUTHOR]