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Accurate assessment of life history and population ecology of widespread species in ultra‐eutrophic freshwater lakes is a prerequisite for understanding the mechanisms by which widespread species respond to eutrophication. Freshwater pulmonate (Radix swinhoei) is widespread and abundant in many eutrophic water bodies in Asia. Despite its key roles in eutrophic lake systems, the information on life history and population ecology of R. swinhoei is lacking, especially in ultra‐eutrophic freshwater plateau lakes. Here, we conducted a 1‐year survey of R. swinhoei with monthly collections to measure the life history traits (life span and growth), annual secondary production, and population size structure of R. swinhoei in nearshore regions with a high seasonally variation of nutrients in Lake Dianchi, a typic hypereutrophic plateau lake in Southwest China. Our results showed that R. swinhoei had the highest biomass in autumn and had the lowest in winter. Its maximum potential life span was 2.5 years, with three recruitment periods (November, March, and July) within a year. Its annual secondary production and P/B ratio were 137.19 g WW/m2 and 16.05, respectively. Redundancy analysis showed that eutrophication‐related environmental factors had weak correlations with population size structure of R. swinhoei. Our results suggested that R. swinhoei is a typical r‐strategist with high secondary production and thrive in eutrophic environment. Our study can help better understand the mechanisms for widespread species to survive eutrophication and could also be relevant for biodiversity conservation and management of eutrophic ecosystems. [ABSTRACT FROM AUTHOR]

Feeding a growing population and preventing dangerous climate change are two challenges facing humanity. Biological nitrogen (N) fixation is considered a sustainable production measure that helps maintain crop production and mitigate climate change by supplementing alternative N nutrients. However, the simultaneous impacts of symbiotic N fixation (SNF) by leguminous green manure crops on rice crop production and nitrous oxide (N 2 O) emissions remain poorly understood. Here, a field experiment of two annual rotation cycles was conducted to monitor rice yield and the N 2 O emissions under rice (Oryza sativa subsp. japonica Kato.)-wheat (Triticum aestivum L.) (RW) and rice-hairy vetch (Vicia villosa Roth.) (RV) cropping systems at three N input rates (0 (N0), 50 (N1) and 100 (N2) kg ha−1) for the upland crops and 200 kg ha−1 for the rice crop. Growing hairy vetch introduced a significant amount of N as SNF to the agroecosystem, ranging from 123 to 182 kg ha−1. Compared to the treatments without N for the RV system, the N1 and N2 treatments significantly increased the amount of SNF by 44–47% and 19%− 24%, respectively. The cumulative N 2 O emissions from SNF ranged from 0.28–0.65 kg ha−1, with the N 2 O emission factor from SNF (EF SNF) ranging from 0.18%− 0.52% for the RV system. The RV system significantly decreased the N 2 O emission factor from the total N input (EF TN) by an average of 10.0% compared with the RW system. The RV-N1 treatment produced an obviously lower EF TN , averaging 0.37%, than the other treatments receiving N applications. Compared to the RW system, the RV system slightly increased rice yield by an average of 3.5%. Therefore, the most appropriate N application rate was 50 kg ha−1 for the leguminous crop, and SNF of leguminous green manure could serve as complementary to mineral N fertilizers for reducing N 2 O emissions while improving soil quality and rice yield in paddy field. [Display omitted] • Symbiotic nitrogen fixation (SNF) contributed 58.1-84.9% of N uptake by hairy vetch. • N 2 O emission factor from SNF (0.18%−0.52%) was firstly established in agroecosystems. • The N1 at 50 kg ha−1 facilitated SNF and reduced N 2 O emission factor of total N input. [ABSTRACT FROM AUTHOR]

Knocking down the oncogene ROC1 with siRNA inhibits the proliferation of cancer cells by suppressing the Neddylation pathway. However, methods for delivering siRNA in vivo to induce this high anticancer activity with low potential side effects are urgently needed. Herein, a folic acid (FA)-modified polydopamine (PDA) nanomedicine used in photothermal therapy was designed for siRNA delivery. The designed nanovector can undergo photothermal conversion with good biocompatibility. Importantly, this genetic nanomedicine was selectively delivered to liver cancer cells by FA through receptor-mediated endocytosis. Subsequently, the siRNA cargo was released from the PDA nanomedicine into the tumor microenvironment by controlled release triggered by pH. More importantly, the genetic nanomedicine not only inhibited liver cancer cell proliferation but also promoted liver cell apoptosis by slowing ROC1 activity, suppressing the Neddylation pathway, enabling the accumulation of apototic factor ATF4 and DNA damage factor P-H2AX. Combined with photothermal therapy, this genetic nanomedicine showed superior inhibition of the growth of liver cancer in vitro and in vivo. Taken together, the results indicate that this biodegradable nanomedicine exhibits good target recognition, an effective pH response, application potential for genetic therapy, photothermal imaging and treatment of liver cancer. Therefore, this work contributes to the design of a multifunctional nanoplatform that combines genetic therapy and photothermal therapy for the treatment of liver cancer. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is Available in the Text. [ABSTRACT FROM AUTHOR]

The holarctic genus Mesenchytraeus is one of the species‐rich genera in the family Enchytraeidae. Changbai Mountain supports high diversity of Mesenchytraeus species, making it an ideal area to explore species boundaries. We explored species boundaries of Mesenchytraeus using an integrative approach. Morphological taxonomy recognized 10 species in this region, five of them new to science. In contrast, molecular species delimitation analyses showed that there are at least 16 species, 11 of them new to science. Clear genetic gaps were observed among species with high interspecific distances (10%–21.2%) and low intraspecific distances (0.2%–6.7%) based on uncorrected p‐distance of the COI gene. Morphological species complex M. spermatoglomeratus consists of three species, M. spermatoglomeratus Zhang, Lu & Xie, 2018 sensu stricto, M. rijina sp. n., and M. manchu sp. n. The M. duodiverticulus complex consists of M. duodiverticulus sp. n. and M. similiduodiverticulus sp. n. The M. monodiverticulus complex consists of M. monodiverticulus Shen, Chen & Xie, 2012 sensu stricto, M. ngulen sp. n., M. zhenggulen sp. n., and M. fokulen sp. n. Further new species, distinguishable with morphological as well as molecular methods, are M. similigigachaetus sp. n., M. parvidiverticulus sp. n., M. digitalisdiverticulus sp. n., and M. infradiverticulus sp. n. Finally, we inferred the morphogenetic processes of spermathecae and sperm bundles, and filtrated some morphological characters which are useful to identify species. As the first attempt in this genus, our study provides an opportunity to discuss the currently used taxonomic criteria and acquire new ideas for the taxonomy of enchytraeids. [ABSTRACT FROM AUTHOR]

Our patient represents the first reported case of neoadjuvant immune checkpoint inhibitor (ICI) therapy for stage II melanoma. At this time, surgical resection and adjuvant therapy remain the standard of care for high-risk stage II and clinical stage III melanoma.[1] However, appropriate patients can be considered for neoadjuvant therapy in ongoing clinical trials. [Extracted from the article]

With excessive nitrogen (N) input, high nitrous oxide (N2O) emissions are frequently observed in greenhouse vegetable fields. We hypothesized that the underlying production mechanisms can be derived across a wide selection of vegetable fields in the middle and lower reaches of the Yangtze River. Thus, we investigated the emission characteristics and relative contributions of ammonia-oxidizing archaea (AOA) and bacteria (AOB) and other microbial processes to the N2O production from five long-term greenhouse vegetable fields through an incubation experiment with combined inhibition methods. The results showed that the ammonia oxidation process is the dominant contributor to N2O production at all five sites, accounting for 88–97% of the total N2O emissions. Regardless of acidic, neutral, or alkaline soil, AOA-driven N2O emission rates were consistently higher than AOB-driven N2O emission rates. Both AOA-driven and AOB-driven N2O emissions exhibited positive correlations with soil pH, with significant increases in soil N2O production associated with high pH levels. Therefore, general production mechanisms were derived, such that more attention should be paid to AOA-driven N2O emissions and to vegetable soils with a relatively high pH in the middle and lower reaches of the Yangtze River. [ABSTRACT FROM AUTHOR]

Microcystin-LR (MCLR) and copper are commonly found in eutrophic water bodies because of eutrophic run-offs, cyanobacterial blooms, and copper algicide applications. However, the ecotoxicological risk of their combination remains unknown. This study investigated the effect of MCLR, Cu, and their mixture on the growth and physiological responses of Vallisneria natans . Results showed that the combined toxicity of them was concentration dependent. Synergistic effects were elicited at low concentrations of MCLR and Cu exposure (≤0.25 + 0.64 mg/L). Additive or antagonistic effects were induced at higher concentrations. Single and combined exposures could induce oxidative stress, such as increased superoxide anion radical levels. To cope with oxidative stress, V. natans could activate their antioxidant defense systems, such as enhanced superoxide dismutase production and changes in peroxidase activities. Exposure to combined MCLR and Cu (even only with 0.005 + 0.041 mg/L) adversely affected their antioxidant defense systems. As a consequence, malondialdehyde levels significantly increased. The interaction of MCLR and Cu could also significantly increase the bioaccumulations of MCLR and Cu. This increase could be accounted for their synergistic toxic effects on V. natans . Our results suggested that the exacerbated ecological hazard of MCLR and Cu with environmental concentrations may harm aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Aim: Disentangling how stochastic and deterministic processes contribute to variation in beta diversity is a common goal for ecologists and biogeographers. However, such studies are scarce in alpine streams, especially when different diversity facets are considered. Here, we combined different approaches to examine the drivers of taxonomic, phylogenetic and functional beta diversities, and discussed how our results can inform community assembly and biodiversity conservation in Tibetan streams. Location: Tibet plateau. Taxon: Macroinvertebrates. Methods: We first partitioned multiple facets of beta diversity (Btotal) into species replacement (Brepl) and richness difference (Brich) as well as local (LCBD) or species (SCBD) contributions. Then, we applied ordination methods to examine the relative importance of local, climatic and spatial factors on Btotal, Brepl and Brich, respectively. We explored community assembly rules using null models based on trait and phylogeny structure. Results: Btotal displayed high values and was primarily driven by Brepl. Local, climatic and spatial factors were poor predictors of the different facets of beta diversity. Null models showed that the diversity metrics did not differ from those of null expectations, suggesting that most individual streams might be occupied by species that were merely random draws from the functional or phylogenetic pools available in this region. Partitioning beta diversity into LCBD and SCBD implied that the upper canyon streams were more unique than those at lower elevations and can be valuable for biodiversity conservation. Main Conclusions: Analysing multiple facets of beta diversity provide important insights into community assembly that cannot be acquired by focusing on taxonomic diversity only. Using a multi‐faceted approach involving species, phylogenetic and trait data, our study not only sheds light on the assembly mechanisms of macroinvertebrate communities in alpine streams, but also bring inspirations for biodiversity conservation in the 'World's Third Pole' that is highly sensitive to global change. [ABSTRACT FROM AUTHOR]

The highly endemic diversity of the Yun-Gui plateau lakes has decreased severely in recent decades. Protecting these native species is a challenge, in part because their biology and population ecology remain unexplored. We investigated 1 focal endangered gastropod species (Margarya melanioides) in 1 plateau lake: 1) to quantify spatiotemporal variation in population abundance and size structure, and 2) to identify the key variables influencing these variations. Density was 0.068 individuals/m2 with an estimated total population size of 2.1 × 107 individuals. The size-frequency distribution was skewed toward larger, mature individuals (40.0-60.0 mm), a result indicating that the population is aging. Population size structure showed high spatial heterogeneity, and density was highest in the north-central region of the lake. Redundancy analysis indicated that human-induced environmental degradation strongly controlled the spatial patterns in size-structure. This species has experienced a remarkable decrease in range and population size over the past 50 y, and the population probably will collapse by 2015. The decline could be attributed to demographic drift, environmental filtering, human harvesting, and its limited dispersal ability. Our studies should give useful information for building efficient conservation strategies for M. melanioides and other threatened plateau gastropods. Further studies are needed on the population ecology and reproductive biology of M. melanioides, particularly on its reproductive behavior and size-specific survivorship. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, structural configuration of layered Li-ion battery electrode plates is evaluated by analytically formulating the diffusion induced stress. Both symmetric electrode and asymmetric bilayer electrode are discussed. The thickness ratio and the modulus ratio of current collector to active plate are analytically identified to be the important influence parameters on the stress. Applying a material with smaller elastic modulus for current collector could reduce the peak stresses in both current collector and active plate. Increasing the thickness of current collector would reduce the stress in itself while promote the stress in active plate. Therefore, from mechanical viewpoint on designing an electrode, the material for current collector should be as soft and flexible as possible. And the thickness of current collector should be in an appropriate range. Basically, it should be as small as possible on the precondition that the mechanical strength is satisfied. Finally, effects of three charging conditions, i.e. uniform, galvanostatic, and potentiostatic, on the diffusion induced stress is discussed. It is found the maximum stresses for three cases are linear to the total amount of intercalated lithium ions. Based on the stresses, an optimized charging operation, i.e. first galvanostatic followed by potentiostatic, is suggested. [Copyright &y& Elsevier]

In-plane compressive strength of z-pinned unidirectional composites is predicted by using variational principle and maximum shear strength criterion. The fiber waviness and the fiber volume content concentration, which are inhomogeneously distributed, as well as the resin-rich pocket, are taken into account. The predicted results are in good agreement with the test data. The effects of pin parameters on the compressive strength of z-pinned laminates are discussed in detail. The results showed that in-plane compressive strength of laminates decreases as the diameter of pin increases under the same pin volume content. Compressive strength decreases as the pin volume content increases under the same pin diameter. The non-linear shear property of matrix has relatively remarkable influence on compressive strength of unidirectional z-pinned laminates when pin diameter is small. [ABSTRACT FROM AUTHOR]

In this article a theoretical model based upon micromechanical analysis of damage is developed to predict nonlinear stress-strain response and progressive failure of continuous fiber-reinforced metal matrix composites (MMCf). A micromechanically analytical model using an influence function superimposition technique is developed to derive stress profiles for any configuration of breaks in MMCf under tensile loading, by considering local matrix tensile yield and interface yield (or sliding). Several hundred Monte Carlo simulations including these failure mechanisms have been executed to simulate failure process and determine statistically the ultimate strength distributions of the composites. Site discretization, material sizes and shape parameter in Weibull distribution are studied to investigate the dependence of ultimate strength on these factors. It is shown that the size dependence of composite ultimate strength is dominated by fiber strength statistics and stress redistribution due to progressive microdamage. [ABSTRACT FROM AUTHOR]

Abstract: The problem of a steady line heat source within a decagonal quasicrystalline half-space, in which the boundary is traction-free, is investigated in detail by applying the complex variable technique. The line heat source is infinitely long in the period direction, then the plane strain condition prevails. The four complex stress functions are derived. It is found that the determination of the complex stress functions is independent of the thermal boundary conditions. The stress fields induced by the heat source are explicitly given based on the complex stress functions. Furthermore, we consider, both qualitatively and quantitatively, the distribution of σ11 on the boundary y=0 of the half-space to demonstrate the influence of the phonon–phason coupling constant R on the stress field. [Copyright &y& Elsevier]

Abstract: This paper is concerned with the problem of two circular inclusions with circumferentially inhomogeneously imperfect interfaces embedded in an infinite matrix in plane elastostatics. Infinite series form solutions to this problem are derived by applying complex variable techniques. The numerical results demonstrate that the interface imperfection, interface inhomogeneity, and interaction among neighboring inclusions (fibers) will exert a significant influence on the stresses along the interfaces and average stresses within the inclusions. [Copyright &y& Elsevier]

This two-part contribution presents a novel and efficient method to analyze the two-dimensional (2-D) electromechanical fields of a piezoelectric layer bonded to an elastic substrate, which takes into account the fully coupled electromechanical behavior. In Part I, Hellinger–Reissner variational principle for elasticity is extended to electromechanical problems of the bimaterial, and is utilized to obtain the governing equations for the problems concerned. The 2-D electromechanical field quantities in the piezoelectric layer are expanded in the thickness-coordinate with seven one-dimensional (1-D) unknown functions. Such an expansion satisfies exactly the mechanical equilibrium equations, Gauss law, the constitutive equations, two of the three displacement–strain relations as well as one of the two electric field-electric potential relations. For the substrate the fundamental solutions of a half-plane subjected to a vertical or horizontal concentrated force on the surface are used. Two differential equations and two singular integro-differential equations of four unknown functions, the axial force, N, the moment, M, the average and the first moment of electric displacement, D0 and D1, as well as the associated boundary conditions have been derived rigorously from the stationary conditions of Hellinger–Reissner variational functional. In contrast to the thin film/substrate theory that ignores the interfacial normal stress the present one can predict both the interfacial shear and normal stresses, the latter one is believed to control the delamination initiation. [Copyright &y& Elsevier]

This two-part contribution presents a novel and efficient method to analyze the two-dimensional (2-D) electromechanical fields of a piezoelectric layer bonded to an elastic substrate, which takes into account the fully coupled electric and mechanical behaviors. In Part I, we have obtained a system of governing integro-differential equations for the structure via a variational principle. This part presents a numerical solution algorithm of the integro-differential equations and the numerical results of some applications. A numerical algorithm for solving the system of four integro-differential equations with strongly singular kernels is developed. The convergence of the numerical algorithm is discussed. The numerical results suggest that the fully coupled electromechanical analysis is helpful for a better understanding of the performance of the piezoelectric sensor and actuator. The interfacial normal stress is much higher than the interfacial shear stress, suggesting that the interfacial normal stress causes a delamination initiation. [Copyright &y& Elsevier]

The local cyclic plasticity of the interface around a broken fiber in ductile matrix composites under the in-phase and out-of-phase thermomechanical fatigue (TMF) loads is analyzed by using the single-fiber shear-lag model. The elastic, perfectly-plastic shear stress–strain relation is used to model the thermomechanical behavior of the fiber/matrix interface. It is shown that the alternating plastic shearing of the interface takes place under an appropriate combination of mechanical stress and thermal load. In the stress versus temperature diagram the so-called cyclic plasticity zone is identified. A new parameter, i.e. the cyclic plasticity length, L−s, is found which is smaller than the yield length, Ls, caused by monotonic loading. The closed-form solutions for L−s, Ls, the fiber stress profiles and the cyclic plastic shear strain range, Δγp, are obtained. L−s and Δγp increase for both the in-phase and out-of-phase TMF conditions as the mechanical load and/or thermal load increase. The in-phase condition produces a higher plastic shear strain range than the out-of-phase condition does. The solutions obtained may be used for modeling fiber/matrix debonding caused by the fiber breakage under TMF fatigue loading. [Copyright &y& Elsevier]

The Orange County Sanitation District (OCSD) is a public agency that provides treatment of wastewater for residents in Orange County, California. The final effluent characteristics at OCSD have been altered in the last 18 years due to the ~20-fold increase of sodium hypochlorite usage for disinfecting waste streams from 2002 to 2010, implementation of the Ground Water Replenishment System (GWRS) in 2008, and conversion to full secondary treatment, together with a major reduction of sodium hypochlorite usage in 2011. This study analyzed infauna data gathered from 1994 to 2016 at the zone of initial dilution (ZID) and reference stations located on the San Pedro Shelf to assess the effects of these treatment process changes on biota in the receiving water. Impacts to the infauna community within the ZID were observed during the period of high chlorine usage, including the increased proportion of the pollution tolerant polychaete Capitella capitata complex from 6.2% in 2003 to nearly 60% in 2010, the lowest Infaunal Trophic Index score in 2009, and the highest Benthic Response Index score in 2006. The degradation of the infauna community in the ZID was correlated with chlorination and was coincidental with the initiation of the GWRS. The infauna community at the ZID recovered rapidly after the implementation of full secondary treatment as indicated by the significant reduction of the relative abundance of C. capitata complex from 59.8% in 2010 to less than 0.1% after 2012, and by the markedly improved community health index scores. This study demonstrated the composition and biointegrity of the infauna community at the ZID varied in response to changes in the wastewater treatment process. Caution should be exercised at wastewater treatment plants when relatively higher dosages of sodium hypochlorite are used over a multi-year period, as this may negatively impact aquatic biota in the receiving water. Unlabelled Image • Infauna health declined in an outfall zone after chlorination of waste streams. • Infauna communities in a reference zone were not affected. • Impact to infauna communities was linked to chlorine usage and chlorine residuals. • Infauna communities rapidly recovered due to improvements in treatment processes [ABSTRACT FROM AUTHOR]

Metallic nanowires (NWs) are essential building blocks for flexible electronics, and experience different deformation modes due to external mechanical loading. Using atomistic simulations, this work investigated the deformation behavior of copper nanowire under coupled tension–torsion loading. A transition in both yielding pattern and dislocation pattern were observed with varying torsion/tension strain ratios. Specifically, increasing the torsion/tension strain ratio (with larger torsional strain) triggered the nucleation of different partial dislocations in the slip system. At low torsion/tension strain ratios, plastic deformation of the nanowire was dominated by stacking faults with trailing partial dislocations pinned at the surface, shifting to two partial dislocations with stacking faults as the strain ratio increases. More interestingly, the NW under tension-dominated loading exhibited a stacking fault structure after yielding, whereas torsion-dominated loading resulted in a three-dimensional dislocation network within the structure. This work thus suggests that the deformation behavior of the NW varies depending on the coupled mechanical loading, which could be beneficial for various engineering applications. [ABSTRACT FROM AUTHOR]

Accurate fire identification can help to control fires. Traditional fire detection methods are mainly based on temperature or smoke detectors. These detectors are susceptible to damage or interference from the outside environment. Meanwhile, most of the current deep learning methods are less discriminative with respect to dynamic fire and have lower detection precision when a fire changes. Therefore, we propose a dynamic convolution YOLOv5 fire detection method using a video sequence. Our method first uses the K-mean++ algorithm to optimize anchor box clustering; this significantly reduces the rate of classification error. Then, the dynamic convolution is introduced into the convolution layer of YOLOv5. Finally, pruning of the network heads of YOLOv5's neck and head is carried out to improve the detection speed. Experimental results verify that the proposed dynamic convolution YOLOv5 fire detection method demonstrates better performance than the YOLOv5 method in recall, precision and F1-score. In particular, compared with three other deep learning methods, the precision of the proposed algorithm is improved by 13.7%, 10.8% and 6.1%, respectively, while the F1-score is improved by 15.8%, 12% and 3.8%, respectively. The method described in this paper is applicable not only to short-range indoor fire identification but also to long-range outdoor fire detection. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) have garnered significant attention as a vital driver of economic growth and environmental sustainability. Nevertheless, ensuring the safety of high-energy batteries is now a top priority that cannot be overlooked during large-scale applications. This paper proposes an innovative active protection and cooling integrated battery module using smart materials, magneto-sensitive shear thickening fluid (MSTF), which is specifically designed to address safety threats posed by lithium-ion batteries (LIBs) exposed to harsh mechanical and environmental conditions. The theoretical framework introduces a novel approach for harnessing the smoothed-particle hydrodynamics (SPH) methodology that incorporates the intricate interplay of non-Newtonian fluid behavior, capturing the fluid-structure coupling inherent to the MSTF. This approach is further advanced by adopting an enhanced Herschel-Bulkley (H-B) model to encapsulate the intricate rheology of the MSTF under the influence of the magnetorheological effect (MRE) and shear thickening (ST) behavior. Numerical simulation results show that in the case of cooling, the MSTF is an effective cooling medium for rapidly reducing the temperature. In terms of mechanical abuse, the MSTF solidifies through actively applying the magnetic field during mechanical compression and impact within the battery module, resulting in 66% and 61.7% reductions in the maximum stress within the battery jellyroll, and 31.1% and 23% reductions in the reaction force, respectively. This mechanism effectively lowers the risk of short-circuit failure. The groundbreaking concepts unveiled in this paper for active protection battery modules are anticipated to be a valuable technological breakthrough in the areas of EV safety and lightweight/integrated design. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mohs micrographic surgery may be discontinued with positive margins as an anticipated strategy for multidisciplinary care or as an unanticipated occurrence. Management of primary tumors has not been compared after anticipated versus unanticipated incomplete Mohs micrographic surgery (iMMS). OBJECTIVE: To compare rates and timing of adjuvant surgery after iMMS and final margin status when iMMS is anticipated versus unanticipated. Secondary outcomes were preoperative and intraoperative clinicopathologic factors associated with iMMS. METHODS: Cases of iMMS of keratinocyte carcinomas at a tertiary academic center between 2005 and 2022 were classified as anticipated (preoperative assembly of multidisciplinary teams) or unanticipated (ad hoc management of positive margins). Rate, timing, and final margin status of adjuvant surgery was compared between anticipated and unanticipated iMMS cohorts using χ2/Fisher exact test for categorical variables and t -test for continuous variables. RESULTS: Of 127 iMMS cases, 51.2% (65/127) were anticipated. Anticipated iMMS cases were more likely to undergo additional resection (98.5% vs 72.6%, p <.001), with fewer delays (3.9 vs 13.2 days, p <.001) and higher rates of final margin clearance (84.6% vs 59.7%, p <.001). CONCLUSION: When iMMS is anticipated as part of multidisciplinary care, patients are more likely to undergo additional resection, with fewer delays to next surgery and higher final margin clearance rates. [ABSTRACT FROM AUTHOR]

The lithium diffusion in graphite anode, which is the most widely used commercial electrode material today, affects the charge/discharge performance of lithium-ion batteries. In this study, the anisotropic strain effects on lithium diffusion in graphite anodes are systematically investigated using first-principles calculations based on density functional theory (DFT) with van der Waals corrections. It is found that the effects of external applied strains along various directions of Li x C 6 (i.e., perpendicular or parallel to the basal planes of the graphite host) on lithium diffusivity are different. Along the direction perpendicular to the graphite planes, the tensile strain facilitates in-plane Li diffusion by reducing the energy barrier, and the compressive strain hinders in-plane Li diffusion by raising the energy barrier. In contrast, the in-plane biaxial tensile strain (parallel to the graphite planes) hinders in-plane Li diffusion, and the in-plane biaxial compressive strain facilitates in-plane Li diffusion. Furthermore, both in-plane and transverse shear strains slightly influence Li diffusion in graphite anodes. A discussion is presented to explain the anisotropic strain dependence of lithium diffusion. This research provides data for the continuum modelling of the electrodes in the lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The interfacial debonding between the active layer and the current collector has been recognized as a critical mechanism for battery fading, and thus has attracted great efforts focused on the related analyses. However, much still remains to be studied regarding practical methods for suppressing electrode debonding, especially from the perspective of mechanics. In this paper, a pre-strain strategy of current collectors to alleviate electrode debonding is proposed. An analytical model for a symmetric electrode with a deformable and limited-thickness current collector is developed to analyze the debonding behavior involving both a pre-strain of the current collector and an eigen-strain of the active layers. The results reveal that the well-designed pre-strain can significantly delay the debonding onset (by up to 100%) and considerably reduce the debonding size. The critical values of the pre-strain are identified, and the pre-strain design principles are also provided. Based on these findings, this work sheds light on the mechanical design to suppress electrode degradation. [ABSTRACT FROM AUTHOR]

Due to the complex mesostructure and components of composite active layers in lithium-ion battery (LIB) electrodes, coupled with the concentration-dependent material properties and eigenstrains, efficiently estimating the effective modulus of the active layers remains a great challenge. In this work, the classic Mori–Tanaka method is found to be unable to estimate the modulus of the active layer. By realizing the importance of the mesostructure feature, a rod-rod model is proposed. The resulting modulus is expressed analytically. It is shown that the rod-rod model can accurately estimate the modulus evolution of the active layer if the material properties of the components and the evolution of volume fractions are known in advance. Moreover, a simplified rod-rod model is also developed to reduce the complexity of the proposed method. By knowing the volume fractions at two arbitrary states of charge and subsequently determining two constants, the simplified model can estimate the modulus efficiently. Considering both its accuracy and its simplicity, the simplified rod-rod model is the most suitable for the estimation. Thus, the methods developed in this work provide a new perspective for analyzing the material properties of composite active layers in LIB electrodes. [ABSTRACT FROM AUTHOR]

The in situ curvature measurement of bilayer beam electrodes is widely used to measure the lithium concentration-dependent material properties of lithium-ion battery electrodes, and further understand the mechano–electrochemical coupling behaviors during electrochemical cycling. The application of this method relies on the basic assumption that lithium is uniformly distributed along the length and thickness of the curved active composite layer. However, when the electrode undergoes large bending deformation, the distribution of lithium concentration in the electrolyte and active composite layer challenges the reliability of the experimental measurements. In this paper, an improved experiment for simultaneously measuring the partial molar volume and the elastic modulus of the graphite composite electrode is proposed. The distance between the two electrodes in the optical electrochemical cell is designed and graphite composite electrodes with four different thickness ratios are measured. The quantitative experimental data indicate that the improved experiment can better satisfy the basic assumptions. The partial molar volume and the elastic modulus of the graphite composite electrode evolve nonlinearly with the increase of lithium concentration, which are related to the phase transition of graphite and also affected by the other components in the composite active layer. This improved experiment is valuable for the reliable characterization of the Li concentration-dependent material properties in commercial electrodes, and developing next-generation lithium batteries with more stable structures and longer lifetimes. [ABSTRACT FROM AUTHOR]

A preface to the journal "Mechanics of Advanced Materials & Structures" is presented.

This article demonstrates the design of charging strategies for lithium ion batteries with considering the balance between diffusion induced stress and total charge time for two- and three-stage charge methods. For the two-stage galvanostatic-potentiostatic charge method the low mechanical stress can be achieved without increasing total charge time by switching the galvanostatic to the potentiostatic at the time moment when the lithium concentration at the surface of particles reaches the limit c ¯ surf = 0 . A three-stage method, which consists of an initial galvanostatic stage of high current, a galvanostatic stage of low current and a potentiostatic ending stage, is suggested. Employing the initial galvanostatic stage of high current is helpful not only in accelerating the charge process, but also in controlling the mechanical stress once the electrical current and time duration of the initial galvanostatic stage are properly designed. [ABSTRACT FROM AUTHOR]

A multiscale approach based upon the micromechanical analysis of multiple damage events at the fibre/matrix scale is developed to investigate the mechanical behaviour of unidirectional composites subjected to tensile loading. The composites are reinforced with bamboo fibres under conditions of fibre breakage and matrix transverse cracking, by considering longitudinal splitting derived from the weak interfacial bonding between fibre and matrix. Due to the statistical nature, an improved Weibull model is employed to describe fibre strength distributions affected by the diameter change in the fibres. A simulation scheme coupled with the Monte Carlo method is performed to characterise the progressive failure in the composite. Compared with experimental results, the validity of the model for composite strength prediction is examined as well. [ABSTRACT FROM AUTHOR]

The state of charge (SOC) or the depth of discharge (DOD) to and the time to delamination onset and the critical size for delamination, which are potentially important in lithium ion battery design for preventing the patterned thin film electrodes from delamination, are investigated. A theoretical approach based on the cohesive model is proposed to formulate the time to and the SOC (or DOD) to delamination onset, as well as the critical size for patterned disk-like electrodes. It is found that for negative electrode the delamination initiation is dominated by mode-II during cell charging and by mode-I during cell discharging. For positive electrode both delamination modes are theoretically possible during cell charging. When the electrochemical load factor i ¯ is very high, the mode-I delamination is possible and an optimal size of electrodes exists for a given maximum i ¯ . The SOC to mode-II delamination onset decreases significantly with increasing dimensionless radius, being independent of i ¯ . When the mode-II is the dominated mode the critical size for delamination exists, and a formula for the critical size for delamination has been deduced, which is proportional to interface ductility and inversely proportional to maximum volumetric strain. [ABSTRACT FROM AUTHOR]

Understanding the relative role of dispersal dynamics and niche constraints is not only a core task in community ecology, but also becomes an important prerequisite for bioassessment. Despite the recent progress in our knowledge of community assembly in space and time, patterns and processes underlying biotic communities in alpine glacierized catchments remain mostly ignored. To fill this knowledge gap, we combined the recently proposed dispersal-niche continuum index (DNCI) with traditional constrained ordinations and idealized patterns of species distributions to unravel community assembly mechanisms of different key groups of primary producers and consumers (i.e., phytoplankton, epiphytic algae, zooplankton, macroinvertebrates, and fishes) in rivers in the Qinghai-Tibet Plateau, the World's Third Pole. We tested whether organismal groups with contrasting body sizes differed in their assembly processes, and discussed their applicability in bioassessment in alpine zones. We found that community structure of alpine river biotas was always predominantly explained in terms of dispersal dynamics and historical biogeography. These patterns are most likely the result of differences in species-specific functional attributes, the stochastic colonization-extinction dynamics driven by multi-year glacier disturbances and the repeated hydrodynamic separation among alpine catchments after the rising of the Qilian mountains. Additionally, we found that the strength of dispersal dynamics and niche constraints was partially mediated by organismal body sizes, with dispersal processes being more influential for microscopic primary producers. Finding that zooplankton and macroinvertebrate communities followed clumped species replacement structures (i.e., Clementsian gradients) supports the notion that environmental filtering also contributes to the structure of high-altitude animal communities in glacierized catchments. In terms of the applied fields, we argue that freshwater bioassessment in glacierized catchments can benefit from incorporating the metacommunity perspective and applying novel approaches to (i) detect the optimal spatial scale for species sorting and (ii) identify and eliminate the species that are sensitive to dispersal-related processes. [Display omitted] • Community assembly in glacierized rivers remain mostly ignored. • We applied multiple analyses to examine the assembly of multiple aquatic taxa. • Community structure was mainly explained by dispersal and historical biogeography. • The strength of dispersal and niche constraints was mediated by body sizes. • Freshwater bioassessment can benefit from incorporating the metacommunity concept. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a strategy to reduce the diffusion induced stress and enhance the capacity of a layered electrode by allowing the plastic deformation of current collector. Based on analytical formulations of the stress in whole electrode, three types of elastoplastic behaviors of current collector, i.e. pure elastic deformation, plastic shakedown and cyclic plasticity, are identified. Criterions separating the three cases are proposed. It is found applying a thin current collector and allowing it to plastically yield in the charge/discharge cycles is beneficial not only to capacity as more space can be provided for active materials but also to electrochemical stability because the stress in active layer is significantly reduced. Structural design corresponding to plastic shakedown shows good balance between the said improvements and structural safety, whereas the case of cyclic plasticity further enhances the improvements. Therefore, structural designing scheme is provided for the former case according to the criterion of plastic shakedown but for the latter one based on the Coffin–Manson relation with expected cycle life. [Copyright &y& Elsevier]

BACKGROUND: The relationship of postoperative facial scar assessments among patients, physicians, and societal onlookers is not clearly defined. OBJECTIVE: To identify differences in perceived scar outcomes by different stakeholders. METHODS AND Materials: Retrospective cohort study at a single Mohs micrographic surgery (MMS) center during which scars were assessed by: patients, physicians, and medical student observers not involved in patients' care using the Patient and Observer Scar Assessment Scale (v.2). Eighty-one patients graded their scars at 2 visits: 1 to 2 weeks post-MMS and 3 months post-MMS. Deidentified patient photographs were taken at each visit and graded by 4 physicians and 12 observers. RESULTS : At week 1, there was a significant difference in overall opinion of scar appearance between patient and physicians (p =.001) and medical student observers and physicians (p <.001). Physicians graded scars more favorably. At 3 months, there remained a difference in scar evaluations between patient and physicians (p =.005), whereas medical student observers rated scars more similarly to physicians (p =.404). CONCLUSION : Postoperative scar perceptions differ among stakeholders. Physicians must be mindful of this disparity when counseling patients in the perioperative setting to align patient expectations with realistic scar outcomes. [ABSTRACT FROM AUTHOR]

Prelithiation has been intensively investigated in high-capacity lithium-ion batteries (LIBs). However, the optimization of prelithiation degrees for long service life of LIBs still remains a challenge. The positive efffect of prelithiation on suppressing degradation of LIBs, besides directly pursuing the high first Coulomb efficiency which has been widely reported in the literature, is revealed and discussed based on an analytical model focusing on the interfacial delamination in electrodes. For full charge-discharge cycling, well-designed prelithiation can effectively suppress the delamination and reduce the debonding size by approximately 25%, compared with the case without prelithiation. For the strategy combining partial charge-discharge cycling and prelithiation, the largest reversible capacity without debonding can be significantly improved by approximately 100% with well-designed prelithiation. This work is expected to provide a prelithiation design principle and further improve the mechanical stability of LIB electrodes. [ABSTRACT FROM AUTHOR]

Abstract: An ecological engineering project using water hyacinth for nutrient removal was performed in Baishan Bay of a large shallow eutrophic lake, Lake Dianchi in China. In the present study, a systematic survey of water quality, macrozoobenthos and zooplankton inside (IWH), around (AWH) and far away (FWH) water hyacinth mats was conducted in Baishan Bay from August to October 2010. The results showed that the water quality significantly improved at AWH area. Concentrations of nitrogen and phosphorus were lower and transparency was higher at AWH area than those in IWH and FWH areas. Total densities, dominant species densities, and biodiversity indexes of macrozoobenthos and cladocerans as well as copepods did not differ (P >0.05) among each other in all three areas. It was significantly (P <0.05) different for those of rotifers at IWH area compared to those in AWH and FWH areas. The results might suggest a tremendous potential for the utilization of water hyacinth in the eutrophic lake like Lake Dianchi for nutrients removal. [Copyright &y& Elsevier]

Lithium (Li) concentration-dependent mechanical properties are crucial to the performance and durability of lithium ion batteries. Here, we report an in situ measurement of the evolution of elastic modulus and partial molar volume of commercial graphite electrodes. A bending model is developed to analyze the relationship between large curvature changes and materials properties. The curvature changes of the electrode are captured using a CCD camera during electrochemical cycling. Composite graphite electrodes with different thickness ratios are chosen as the working electrode. The modulus and partial molar volume are extracted which are both associated with the stress evolution of electrodes. The results show that the elastic modulus increases during the second lithiation process, while the partial molar volume shows a stage change corresponding to the phase change of graphite materials. These results are important for the mechanical modeling and provide basic information for the commercial graphite electrodes. Image 1 • Lithium concentration-dependent mechanical properties were measured in situ. • A mechanics model was developed to analyze the curvature deformation of electrodes. • Elastic modulus and partial molar volume of the commercial graphite electrode were reported. [ABSTRACT FROM AUTHOR]

Abstract Partial lithiation strategies for silicon composite electrodes are experimentally investigated in this article. Two types of partial lithiation, i.e. voltage- and capacity-control strategies, are presented. Capacity loss and irreversibility of silicon electrodes are significantly suppressed by either partial lithiation strategy without any complicated modifications or treatments. The capacity of partially lithiated silicon electrodes is even higher than that of fully lithiated one after certain cycles. The images of scanning electron microscope suggest that the mechanical damage generated in partially lithiated electrodes is less than that in fully lithiated one. Furthermore, after dozens of cycles with partial lithiation, capacity decay also slows down in subsequent full charge-discharge cycles. The presented experimental results suggest that the partial lithiation strategy relieves the coupled mechanical-electrochemical degradation and is a promising approach for the long-term use of silicon composite electrodes. [ABSTRACT FROM AUTHOR]

A fully coupling model for the diffusion induced finite elastoplastic bending of bilayer electrodes in lithium-ion batteries is proposed. The effect of the mechanical stress on the lithium diffusion is accounted for by the mechanical part of the chemical potential derived from the Gibbs free energy along with the logarithmic stress and strain. Eight dimensionless parameters, governing the stress-assisted diffusion and the diffusion induced elastoplastic bending, are identified. It is found that the finite plasticity starting from the interface of the bilayer increases the chemical potential gradient and thereby facilitates the lithium diffusion. The full plastic flow makes the abnormal lithium concentration distribution possible, i.e., the concentration at the lithium inlet can be lower than the concentration at the interface (downstream). The increase in the thickness of the active layer during charging is much larger than the eigen-stretch due to lithiation, and this excess thickening is found to be caused by the lithiation induced plastic yield. [ABSTRACT FROM AUTHOR]

Abstract This article sheds light on advantages of fast charging methods with time-varying current. Analytical solutions of concentration and stress for charging processes with general time-varying currents are derived. A fast charging protocol for a multistage constant current of gradually decreasing value is first evaluated. A properly designed multistage constant-current method is able to simultaneously suppress stress overflow and accelerate charging, but stress undulation induced by sharp switching between stages is inevitable. A charging scheme with a nonlinear exponential current is then investigated. The applied current varies continuously and smoothly with time so stress undulation is avoided. Suggestions for the design of an exponential current method are proposed to achieve the best charging acceleration without sacrificing charging capacity or increasing risk of mechanical failures. A well-designed exponential-current method is superior to a multistage constant-current method in accelerating charging speed. [ABSTRACT FROM AUTHOR]

Intercalation of lithium ions into the electrodes of lithium ion batteries is affected by the stress of active materials, leading to energy dissipation and stress dependent voltage hysteresis. A reaction-diffusion-stress coupling model is established to investigate the stress effects under galvanostatic and potentiostatic operations. It is found from simulations that the stress hysteresis contributes to the voltage hysteresis and leads to the energy dissipation. In addition, the stress induced voltage hysteresis is small in low rate galvanostatic operations but extraordinarily significant in high rate cases. In potentiostatic operations, the stresses and stress induced overpotentials increase to a peak value very soon after the operation commences and decays all the left time. Therefore, a combined charge-discharge operation is suggested, i.e., first the galvanostatic one and then the potentiostatic one. This combined operation can not only avoid the extreme stress during operations so as to prevent electrodes from failure but also reduce the voltage hysteresis and energy dissipation due to stress effects. [ABSTRACT FROM AUTHOR]

This work focuses on understanding the role of various binders, including sodium alginate (SA), Nafion, and polyvinylidene fluoride (PVDF), on the mechanical behavior and cracking resistance of silicon composite electrodes during electrochemical cycling. In situ curvature measurement of bilayer electrodes, consisting of a silicon-binder-carbon black composite layer on a copper foil, is used to determine the effects of binders on bending deformation, elastic modulus, and stress on the composite electrodes. It is found that the lithiation induced curvature and the modulus of the silicon/SA electrodes are larger than those of electrodes with Nafion and PVDF as binders. Although the modulus of Nafion is smaller than that of PVDF, the curvature and the modulus of silicon/Nafion composite are larger than those of silicon/PVDF electrodes. The moduli of all three composites decrease not only during lithiation but also during delithiation. Based on the measured stress and scanning electron microscopy observations of cracking in the composite electrodes, we conclude that the stress required to crack the composite electrodes with SA and Nafion binders is considerably higher than that of the silicon/PVDF electrode during electrochemical cycling. Thus, the cracking resistance of silicon/SA and silicon/Nafion composite electrodes is higher than that of silicon/PVDF electrodes. [ABSTRACT FROM AUTHOR]

The occurrence and temporal–spatial distributions of 13 antibiotics (tetracyclines, sulfonamides, and fluoroquinolones) in the water of a high-intensity aquaculture lake, Honghu Lake, and its associated river network and ponds were investigated. Tetracycline, oxytetracycline, chlortetracycline, and sulfadiazine are the four dominant antibiotics in this region, with maximum and median concentrations of 1454.8 and 304.8 ng/L, 2796.6 and 161.9 ng/L, 1431.3 and 349.9 ng/L, and 499.5 and 106.5 ng/L, respectively. The median concentrations of the other nine antibiotics are lower than 57.1 ng/L. The highest contaminated sites are located in the Four-lake main canal and its lake inlets. Antibiotic concentrations were higher in November than in May and the concentrations were strongly correlated with water temperature, dissolved oxygen, and nitrates according to redundancy analysis. The source analysis indicated that besides untreated domestic and husbandry sewage, the aquaculture in the lake and ponds is a main source of antibiotics in the study region. The environmental hazards posed by the selected antibiotics were assessed by using the methods of hazard quotient and mixture hazard quotient. The results suggested that tetracycline, oxytetracycline, sulfadiazine, and ciprofloxacin pose medium to high ecological hazard to algae in almost all of the water samples, and the high combination ecological hazards of antibiotics are mainly posed by the high individual hazard quotient of tetracycline in the study area. [ABSTRACT FROM AUTHOR]

Mechanical properties and lithiation-induced stress are crucial to the performance and durability of lithium-ion batteries. Here, we report the evolution of elastic modulus and stress in a silicon/polyvinylidene fluoride (PVDF) composite electrode coated on a copper foil, along with a model for analyzing the large change in the radius of curvature of the composite electrode/copper foil cantilever. The radius of curvature of the cantilever is captured by a video camera during lithiation/delithiation. The elastic modulus of the composite electrode decreases from about 0.64 GPa to 0.18 GPa during lithiation. It decreases further to about 0.10 GPa after delithiation, which is caused by the fracture of the electrode. The magnitude of the compressive stress increases lineally during lithiation and decreases suddenly to reach a steady state value during delithiation. [ABSTRACT FROM AUTHOR]

• Beta diversity weighted by incidence vs abundance data varied differently along urbanization gradient. • Richness difference contributed more to beta diversity weighted by abundance than incidence data. • Stochasticity was more dominant in shaping beta diversity weighted by abundance than incidence data. • Homogenization studies should consider the roles of rare and abundant taxa. Urbanization is one of the major drivers of biotic homogenization (i.e., decrease in beta diversity) in freshwater systems. However, only a few studies have simultaneously examined how urbanization affects multiple facets (i.e., taxonomic, functional and phylogenetic) of beta diversity and its underlying ecological drivers in urban river macroinvertebrates. Here, we distinguished the patterns and ecological mechanisms of multiple facets of macroinvertebrate beta diversity weighted by incidence and abundance data in a subtropical river system with a distinct urbanization gradient. We also investigated how total beta diversity patterns stem from replacement versus richness difference among sites. Our results showed that taxonomic and phylogenetic beta diversities weighted by incidence data were primarily driven by replacement of taxa, whereas the richness difference contributed more to multiple facets of beta diversity based on abundance data. Furthermore, multiple facets of beta diversity decreased with urbanization for both incidence-weighted and abundance-weighted data, but the former showed more substantial decreases. Both replacement and richness difference components contributed roughly equally to the decline of incidence-weighted beta diversity. In contrast, the losses of abundance-weighted beta diversity were mainly associated with replacement of taxa. Variation partitioning results revealed that all beta diversity measures based on incidence data were governed primarily by local and land-use variables, whereas spatial variables were more relevant in driving beta diversity weighted by abundance data. Overall, by comparing different facets and components of beta diversity weighted by incidence versus abundance data, we suggest that incidence-weighted data may be more sensitive in portraying the impacts of urbanization on macroinvertebrate diversity. This likely resulted from the fact that incidence-weighted data shows the importance of rare taxa in shaping homogenization induced by urbanization. [ABSTRACT FROM AUTHOR]

Bilayer electrode, composed of a current collector layer and an active material layer, has great potential in applications of in-situ electrochemical experiments due to the bending upon lithiation. This paper establishes an elastoplastic theory for the lithiation induced deformation of bilayer electrode with consideration of the plastic yield of current collector. It is found that the plastic yield of current collector reduces the restriction of current collector to an active layer, and therefore, enhances in-plane stretching while lowers down the rate of electrode bending. Key parameters that influence the elastoplastic deformation are identified. It is found that the smaller thickness ratio and lower elastic modulus ratio of current collector to an active layer would lead to an earlier plastic yield of the current collector, the larger in-plane strain, and the smaller bending curvature, due to balance between the current collector and the active layer. The smaller yield stress and plastic modulus of current collector have similar impacts on the electrode deformation. [ABSTRACT FROM AUTHOR]

Tensile strength of brittle fibres exhibits statistical distribution and size dependence. In this work, the average strength of bamboo fibre is found to decrease from 568 to 483 MPa as mean diameter increases from 196.6 to 584.3 μm. The morphologies of bamboo fibres with increasing diameters were investigated through Scanning Electron Microscopy (SEM) to demonstrate variations in the quantity of elementary fibres. The influence of elementary fibre distributions on the fibre strength was also studied. A modified Weibull model based on number of elementary fibres is proposed to perform scaling predictions for the fracture strength of the fibres at different between-fibre diameters. It was shown that the predicted results are in reasonable agreement with experimental data, highlighting the adequacies of the new analytical model for describing the diameter dependence of tensile strength. [ABSTRACT FROM AUTHOR]