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As predators are generally larger than their prey, positive body size and trophic position relationships are typically assumed, and these relationships have helped in estimating and predicting the effects of global environmental change on the trophic dynamics of aquatic ecosystems. However, current efforts to confirm the generality of body size-trophic position relationships have focused mainly on interspecific patterns using species-aggregated and averaged data, and little effort has been devoted to assessing how trophic position scales with body size at the intraspecific and community levels as well as exploring its ecological drivers, particularly for fishes in freshwater ecosystems. To fill this gap, we present a broad-scale study of body size-trophic position relationships in freshwater ecosystems at both the intraspecific and community levels using an individual-based body size and isotopic signature dataset that includes 2564 samples of 65 fish species in China. Our results indicate that body size-trophic position patterns at both the intraspecific and community levels can be positive, negative or insignificant. Non-significant patterns predominated at both levels, with slightly more than 30 % showing positive relationships, which highlights that the positive body size-trophic position pattern is not universally prevalent and that body size should be used with caution as a proxy for the trophic position of fishes at both the intraspecific and community levels in freshwater ecosystems. No factor was related to body size-trophic position patterns at the community level, while habitat type, elevation, temperature and fishing pressure were identified as the key determinants of body size-trophic position patterns at the intraspecific level, implying that fishing and climate warming can shift the food-web size structure of freshwater ecosystems by affecting population trophic dynamics.

Despite the existence of a prophylactic vaccine against hepatitis B virus (HBV), chronic hepatitis B virus (CHB) infection remains the leading cause of cirrhosis and liver cancer in developing countries. Because HBV persistence is associated with insufficient host immune responses to the infection, development of an immunomodulator as a component of therapeutic vaccination may become an important strategy for treatment CHB. In the present study, we aimed to design a novel immunomodulator with the capacity to subvert immune tolerance to HBV. We developed a lymphoid organ-targeting immunomodulator by conjugating a naturally occurring, lipophilic molecule, α-tocopherol, to a potent CpG oligonucleotide adjuvant pharmacophore. This approach resulted in preferential trafficking of the α-tocopherol-conjugated oligonucleotide to lymphoid organs where it was internalized by antigen-presenting cells (APCs). Moreover, we show that conjugation of the oligonucleotides to α-tocopherol results in micelle-like structure formation, which improved cellular internalization and enhanced immunomodulatory properties of the conjugates. In a mouse model of chronic HBV infection, targeting CpG oligonucleotide to lymphoid organs induced strong cellular and humoral immune responses that resulted in sustained control of the virus. Given the potency and tolerability of an α-tocopherol-conjugated CpG oligonucleotide, this modality could potentially be broadly applied for therapeutic vaccine development.

Abstract Background The scale degeneration is thought to be related to the adaptation to the extreme environment with cold climate and high-altitude in schizothoracine fishes. Gymnocypris eckloni, a schizothoracine fish living in plateau waters with the elevation above 2500 m, is nearly esquamate and only covered with shoulder scales and anal scales, making it a good model species to study the molecular mechanism of scale degeneration. Results The transcriptomes of shoulder scaled skins (SSS), anal scaled skins (ASS) and scaleless skins (NSS) were sequenced and analyzed in G. eckloni at the age of 1 year. Histological examination showed that shoulder scale had completed its differentiation and anal scale just initiated the differentiation. A total of 578,046 unigenes were obtained from the transcriptomes, with 407,799 unigenes annotated in public databases. A total of 428 and 142 differentially expressed unigenes (DEUs) were identified between SSS and NSS, and between ASS and NSS, respectively, with 45 DEUs that were overlapped. Annotation analysis indicated that these DEUs were mainly enriched in Gene Ontology (GO) terms and KEGG pathways associated with bone and muscle formation, such as myofibril, contractile fiber, cytoskeletal protein binding, muscle structure development, cardiac muscle contraction, hypertrophic cardiomyopathy (HCM) and calcium signaling pathway. Conclusions Our results would provide insights into the molecular mechanisms of scale degeneration in G. eckloni and other congeneric fishes. In addition, the transcriptome data provides candidate genes and markers for future studies.

Abstract Resource polymorphism is a ubiquitous phenomenon in vertebrates and may represent a critical intermediate stage in speciation. Freshwater lakes in high‐altitude areas represent a natural system for understanding resource polymorphism in fishes benefiting from diverse lacustrine environments and species‐poor fish assemblages. We report resource polymorphism in a cyprinid fish, Schizopygopsis thermalis, in Lake Amdo Tsonak Co, a headwater lake in the upper Salween River system. Two discrete intraspecific morphs, planktivorous and benthivorous, were identified according to geometric morphometrics and traditional univariate linear measures. The planktivorous morph exhibits a longer head, longer upper and lower jaw, larger asymptotic standard length (L∞), lower growth rate (k), and higher growth performance index (φ) than the benthivorous morph. With respect to descriptive traits, the planktivorous morph possesses a large, terminal mouth and obvious mucus pores on the cheek and chin, while the benthivorous morph is characterized by a more inferior mouth with a sharpen horny edge on the lower jaw and unconspicuous mucus pores. The discrete pelagic–benthic resources and low interspecific competition in the lake system might drive the initial differentiation of the two morphs, and partial spatial reproductive isolation in breeding further maintains and reinforces the differences between them.

As one of the most sensitive regions to global climate change, Tibet is subject to remarkable changes in biota over the past decades, including endemic fish species. However, no study has attempted to predict the changes in the distribution of Tibetan fishes, leaving a great blank for aquatic conservation in Tibet. Based on the Maximum Entropy model (MaxEnt), this study predicted the changes in the suitable habitats of three endemic fish species, including two species mainly inhabiting the rivers (Glyptosternon maculatum, Oxygymnocypris stewartii) and one species mainly inhabiting lakes (Gymnocypris selincuoensis) in Tibet under two representative concentration pathways (RCP2.6 and RCP8.5) under two future scenarios (2050 and 2090), and explored the impact of the barrier effects of hydropower projects on the suitable habitats of fish. The results showed that under the four scenarios, the net change in the suitable habitats of the G. maculatum was negative (−2.0–−18.8%), while the suitable habitats of the O. stewartii and G. selincuoensis would be expanded, with the net change of 60.0–238.3% and 46.4–56.9%, respectively. Under different scenarios, the suitable habitats of the three species had a tendency to migrate to a higher elevation, and the largest expansion in the range of migration was projected to occur under the 2090-RCP8.5 scenario. In addition, due to the impact of the hydropower projects, the ability of G. maculatum to obtain new suitable habitats from climate change would be reduced by 2.0–8.1%, which was less than the loss induced by climate change (5.5–25.1%), while the suitable habitats of O. stewartii would be reduced by 3.0–9.7%, which was more than the impact of climate change (about 1%). The results of this study have guiding significance for the conservation and management of fish resources diversity in the Yarlung Tsangpo River basin and Siling Co basin of Tibet, and also provide a reference for the coordination and scientific planning of hydropower projects in Tibet.

Global environmental change has altered biotic interactions in ecosystems. Trophic structure is a major characteristic of ecosystems, and understanding the factors determining trophic structure is thus important for predicting the response of ecological dynamics and ecosystem services to future environmental change. Different kinds of drivers, including ecosystem size, productivity, and disturbance, have been proposed to explain trophic structure variation in various ecosystems. Much remains unknown about how these drivers operate in determining trophic structure and its underlying mechanisms, particularly in shallow lakes. Here, we evaluated the relative importance of ecosystem size, productivity and disturbance in influencing the trophic structure of fish assemblages in 30 subtropical shallow lakes. We determined that (1) ecosystem size, productivity and disturbance had no effect on food chain length; (2) the mean trophic level increased with increasing ecosystem size and productivity, with productivity contributing the most to explaining the variance in mean trophic level; and (3) ecosystem size, productivity, and disturbance, alone or combined, affected the proportion of species at specific trophic levels. These results indicate the potential for systematic discrepancies in the drivers of trophic structure among different systems and highlight that focusing on food chain length alone may not be sufficient in reflecting the variation in trophic status. Thus, changes in the mean trophic level and specific trophic-level guilds must be considered in future lake management practices.

Understanding different facets of biodiversity patterns and their ecological drivers are essential for freshwater conservation. This is especially true for fish fauna in the Mekong River, one of the largest rivers in the world, which faces large-scale hydropower development and climate change. Here, we divided the Mekong River into 37 sub-basins to explore the alpha and beta taxonomic and functional diversity of fish fauna and the explanatory power of environmental and spatial factors on fish diversity. We found that species and functional richness varied significantly along environmental gradients, while functional evenness and divergence were weakly correlated with environmental variables. We also found that the high taxonomic beta diversity was mainly contributed by the turnover component, while that of the functional facet was mainly due to the nestedness component. In addition, environmental filtering played a more important role than spatial factors in structuring both taxonomic and functional facets of fish communities. Finally, we found that environmental filtering was more important in determining taxonomic structure than functional structure, which was opposite to the general understanding that functional traits should be better associated with environmental variation. Our study illustrated that functional diversity and taxonomic diversity are complementary ecological indicators when assessing fish diversity of large rivers.

Objective To compare the baseline clinical characteristics between patients with ROS1 -positive and ALK -positive advanced non-small cell lung cancer (NSCLC), and the correlations of these subtypes with the distribution of metastases. Methods We compared the clinical characteristics and imaging features of patients with ROS1 -positive and ALK -positive NSCLC using statistical methods. Results Data for 232 patients were analyzed. Compared with ALK -positive NSCLC, ROS1 -positive NSCLC was more likely to occur in women (71% vs 53%), and primary lesions ≤3 cm were more common in patients with ROS1 -positive compared with ALK -positive NSCLC (58% vs 37%). There was no significant difference in the distribution of metastases between the two groups. Subgroup analysis within the ROS1 -positive group showed that, compared with primary lesions >3 cm, primary lesions ≤3 cm were more likely to present as peripheral tumors (72% vs 43%) and more likely to exhibit non-solid density (44% vs 4%). Conclusions Although ROS1 -positive and ALK -positive NSCLCs show similar clinical features, the differences may help clinicians to identify patients requiring further genotyping at initial diagnosis.

Surrogate species approaches are widely employed by conservation biologists to help address biodiversity conservation issues when distribution and abundance data for most species of conservation concern are not available or are limited due to insufficient funding and support. However, global reviews of research statuses and trends in the ecological uses of various surrogate approaches in ecosystem conservation are relatively scarce. Here, to fill identified knowledge gaps, we comparatively analyze the research hotspots and trends of five surrogate approaches (i.e., keystone, flagship, umbrella, indicator, and focal species) in vertebrates based on research publications from 1962 to 2019. We found that surrogate species have increased focus since the 1990s. The five individual surrogate approaches showed clear differences in terms of scientific outputs and focal themes, which could be attributed to country/territory and journal preferences. We also found that research activities were mainly conducted in terrestrial ecosystems with mammals and birds, while freshwater species were disproportionately considered relative to the threats they face. In addition, we found that the focal themes changed from pollution monitoring to climate change and conservation strategy. Our study showed that “species distribution model”, “protected areas” and “habitat selection” are possible hotspots of future research using surrogate approaches under the consistent effects of climate change and habitat fragmentation. This study highlights the different uses of individual surrogate approaches and potential imbalances in conservation efforts among ecosystems and taxa, providing a reference for conservation management.

Teleost otoliths provide a pivotal medium for studying changes in population structure and population dynamics of fish. Understanding the otolith-fish size relationship and intraspecies variation in otolith morphology is essential for the accurate assessment and management of fishery resources. In our study, we aimed to estimate the relationships between otolith morphological measurements and fish length, and detect differences in the otolith morphology of planktivorous and benthivorous morphs of Schizopygopsis thermalis in Lake Amdo Tsonak Co on the Qinghai-Tibet Plateau (QTP). Both morphs exhibited strong linear otolith-fish size relationships; otolith morphology was sexually dimorphic in each morph; the morphs differed significantly in otolith shape and size (e.g., posterior side, the region between the posterior and ventral otolith, otolith length, circularity, and surface density). In addition, we found that the differences in otolith morphology between morphs are related to habitat preferences, diet, and growth. Basic data on the biology of S. thermalis are essential for poorly studied Lake Amdo Tsonak Co, and our study emphasizes that intraspecific variation in otolith morphology should be taken into consideration when differentiating stocks, populations, and age classes based on otolith morphology.

Drawing scheduling is the most important process in block cave mining. The traditional analysis process of drawing scheduling is random and inefficient without system scientific analysis. A mixed integer programming method was proposed in this paper to solve the optimization problem of drawing scheduling. Taking the ore reserve quantity, ore grade, drawing index and production scheduling index as the constraints and the grade fluctuation as the objective function, a drawing scheduling optimization model was built based on the mixed integer programming method. It was solved with the CPLEX solver invoked by model language that was programmed with YALMIP in MATLAB for a certain copper mine. Finally, the optimal arrangement scheme of drawing scheduling was obtained. It is proved that this model is scientific and feasible, the grade fluctuation reduces by 18%, and compared with the traditional, this drawing scheduling saves costs by meeting the desired production quantity more closely and reducing the employee time spent on preparing schedules.

Identifying the spatial pattern of fish assemblages and the correlation between fish assemblages and environmental factors is basic for conserving and managing stream fishes. Based on data collected from 91 sampling segments within first-order through third-order streams of the Xin'an basin, China, we examined the spatial variation of fish assemblages in this area and related it to local, river-network and catchment factors. We found that fish species richness significantly increased from first-order to second- and third-order streams, but assemblage structures showed no among-stream variation. When the independent influence of the three categories of factors was considered, fish assemblages were significantly related to local habitat (e.g. wetted and substrate heterogeneity), tributary spatial position (e.g. confluence link and distance from mouth) and land use (e.g. agriculture and urbanization areas), respectively. However, when the effects of the these factors were considered jointly, local habitat and tributary spatial position were more important in influencing fish assemblages than land use. Our results suggest that fish assemblages in the headwater streams of the Xin'an basin were mainly determined by both local and spatial factors. The landscape data should be further refined in the future to provide more information for assessing how land use influence stream fishes.

Piezoelectricity in diphenylalanine peptide nanotubes (PNTs) suggests an avenue towards green piezoelectric devices. Here the authors show ‘smart’ PNTs whose polarization can be controlled with an electric field, and a resultant power generator which harvests biomechanical energy with high power density.

Background/Aims: The aggressive manner of non-small cell lung cancer (NSCLC) cells accounts for the majority of the lethality of the disease. Recently, increased astrocyte elevated gene-1 (AEG-1) levels have been shown to closely correlate with poor prognosis of NSCLC, whereas the underlying mechanisms are not clear. Methods: We examined the AEG-1 and matrix metalloproteinase 7 (MMP7) levels in NSCLC tissues, compared to the paired adjacent non-tumor lung tissue. We modulated AEG-1 levels in NSCLC cells, and examined its effects on MMP7 levels by RT-qPCR, on cellular protein by Western blot, and on secreted protein by ELISA. We also examined the cell invasiveness in AEG-1-modified NSCLC cells in a transwell cell migration assay. We used specific signal pathway inhibitors to treat AEG-1-modified NSCLC cells and examined its effects on MMP7. Results: AEG-1 and MMP7 levels were both significantly increased in NSCLC tissues, compared to the paired adjacent non-tumor lung tissue. The AEG-1 and MMP7 levels were strongly correlated. Overexpression of AEG-1 in NSCLC cells significantly increased MMP7 levels and cell invasiveness, while AEG-1 depletion in NSCLC cells significantly decreased MMP7 levels and cell invasiveness. Application of a specific MAPK-p42/p44 inhibitor, but not application of specific inhibitors for MAPK-p38, PI3k/Akt, or JNK signaling pathways, to AEG-1-overexpressing NSCLC cells substantially abolished the AEG-1-mediated MMP7 up regulation. Conclusion: AEG-1 promotes NSCLC cell invasiveness through MAPK-p42/p44-dependent activation of MMP7.

Strain-induced polarization charges in a piezoelectric semiconductor effectively modulate the band structure near the interface and charge carrier transport. Fundamental investigation of the piezotronic effect has attracted broad interest, and various sensing applications have been demonstrated. This brief review discusses the fundamentals of the piezotronic effect, followed by a review highlighting important applications for strain sensors, pressure sensors, chemical sensors, photodetectors, humidity sensors and temperature sensors. Finally, the review offers some perspectives and outlook for this new field of multi-functional sensing enabled by the piezotronic effect.

Abstract ATP-citrate lyase (ACL), one of the lipogenic enzymes, catalyses the formation of acetyl-coenzyme A (CoA) involved in the synthesis of fatty acid and cholesterol. In pig, very little is known about the ACL gene. In this work, the mRNA differential display technique was used to analyse the differences in gene expression between Meishan and Large White pigs and the F1 hybrids of both direct and reciprocal crosses. Our results show that among the differentially expressed genes ACL is up-regulated in the backfat of the F1 hybrids. After cloning and analysing the fulllength cDNA and the 870 bp 5'-flanking sequence of the porcine ACL gene, a C/T mutation at position -97 bp upstream of the transcription site was detected. Luciferase activity detection showed that this mutation changed the transcriptional activity. In F1 hybrids, the heterozygous genotype CT was more frequent than the homozygous genotypes CC and TT. Real-time PCR analysis showed that in Meishan pigs, ACL mRNA expression was more abundant in individuals with genotype CT than in those with genotype CC or TT or in Large White pigs. These results indicate that the C/T mutation affects ACL mRNA expression, probably via the activator protein 2.

Background: In the aftermath of bereavement, our research explores the subtleties of Prolonged Grief Disorder (PGD), focusing particularly on its correlation with suicidal behaviors and their variation across genders. This study seeks to elucidate the impact of gender on these behaviors among individuals suffering from PGD, thereby enhancing our understanding and facilitating the development of tailored therapeutic interventions. Methods: By November 24th, 2023, we had rigorously reviewed key databases such as PubMed, Web of Science, Cochrane Library, PsycINFO, and Embase. Independently, two researchers conducted detailed interviews and filled out questionnaires with participants to gather demographic information and record instances of prolonged grief disorder. The study also meticulously tracked occurrences of suicidal ideation, suicide attempts, suicide deaths, and self-injury among the participants. Results: The findings indicate that 22.34% of males reported suicidal ideation (95% CI: 21.33--23.35), a figure that rises to 26.84% among females (95% CI: 25.99--27.69). Notably, 12.11% of males attempted suicide (95% CI: 11.49--12.72), marginally surpassing the 9.60% observed in females (95% CI: 9.17--10.04). More striking disparities were observed in suicide deaths, with rates for males at 3.66% (95% CI: 3.32--4.00) compared to a notably higher 7.12% for females (95% CI: 6.44--7.81). Furthermore, the incidence of self-injury was lower among males, at 2.48% (95% CI: 2.03--2.94), than in females, who reported a rate of 5.09% (95% CI: 4.69--5.49). These patterns underscore the critical need for gender-specific interventions aimed at reducing these significant disparities. Conclusion: This study distinctly underscores the profound impact of gender on the manifestation of suicidal behaviors in individuals afflicted with prolonged grief disorder. It reveals that females are more prone to suicidal ideation, self- injury, and suicide deaths, while males predominantly exhibit a higher incidence of suicide attempts and risk-taking behaviors. These unmediated trends highlight the necessity for gender-specific clinical interventions tailored to address particular behaviors and modify prevalent patterns that typically resist conventional approaches. Systematic review registration: PROSPERO (york.ac.uk), identifier CRD42023480035. [ABSTRACT FROM AUTHOR]

Due to its unique climate and geographic location, Siling Co National Nature Reserve, located in the northwest of the Tibet Autonomous Region of China, is an important natural habitat, a hotspot of endemism, and sustains numerous endangered species. Climate change and warming temperatures, invasion by non-native species and human disturbance are serious threats to the Tibetan Plateau's local biodiversity and specialized ecosystems. To better protect biodiversity and ecosystem functions in the specialized endemic habitats of the Plateau, we summarize the status, threats and protective conservation measures in the Reserve. It is hoped that this study will provide useful information and strategies for biodiversity conservation for the Tibetan Plateau and other highland regions. [ABSTRACT FROM AUTHOR]