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1.
Am J Primatol ; : e23676, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148233

RESUMO

Using unmanned aerial vehicles (UAVs) for surveys on thermostatic animals has gained prominence due to their ability to provide practical and precise dynamic censuses, contributing to developing and refining conservation strategies. However, the practical application of UAVs for animal monitoring necessitates the automation of image interpretation to enhance their effectiveness. Based on our past experiences, we present the Sichuan snub-nosed monkey (Rhinopithecus roxellana) as a case study to illustrate the effective use of thermal cameras mounted on UAVs for monitoring monkey populations in Qinling, a region characterized by magnificent biodiversity. We used the local contrast method for a small infrared target detection algorithm to collect the total population size. Through the experimental group, we determined the average optimal grayscale threshold, while the validation group confirmed that this threshold enables automatic detection and counting of target animals in similar datasets. The precision rate obtained from the experiments ranged from 85.14% to 97.60%. Our findings reveal a negative correlation between the minimum average distance between thermal spots and the count of detected individuals, indicating higher interference in images with closer thermal spots. We propose a formula for adjusting primate population estimates based on detection rates obtained from UAV surveys. Our results demonstrate the practical application of UAV-based thermal imagery and automated detection algorithms for primate monitoring, albeit with consideration of environmental factors and the need for data preprocessing. This study contributes to advancing the application of UAV technology in wildlife monitoring, with implications for conservation management and research.

2.
Opt Express ; 31(2): 2492-2507, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785262

RESUMO

The Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2) can measure the global surface with unprecedented resolution. Accurate classification of land and sea data is the prerequisite for generating high-quality data products. Current land-sea classification methods rely on assisted data or manual participation, and the automation degree cannot meet the needs of massive data processing. Therefore, using the land-sea difference of photon-counting LiDAR data, an index called normalized photon rate-elevation ratio (NPRER) is designed. Inspired by this, an automatic land-sea classification method is proposed, and the results are obtained through preliminary classification, reclassification, and post-processing enhancement. The results in Cook Inlet, Alaska, show that NPRER can measure the probability of sea appearance in the nearshore environment. At the same time, the automatic classification method can achieve an overall accuracy of 97.98%. The changes in the coastal type, data collection time, and classification feature sets have little influence on this method. Therefore, the method provides a reliable technical scheme for improving the automation of land-sea classification of satellite-based photon-counting LiDAR data.

3.
Small ; 17(19): e2005248, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33734598

RESUMO

Tremendous efforts have been dedicated to the development of high-performance electrochemical energy storage devices. The development of lithium- and sodium-ion batteries (LIBs and SIBs) with high energy densities is urgently needed to meet the growing demands for portable electronic devices, electric vehicles, and large-scale smart grids. Anode materials with high theoretical capacities that are based on alloying storage mechanisms are at the forefront of research geared towards high-energy-density LIBs or SIBs. However, they often suffer from severe pulverization and rapid capacity decay due to their huge volume change upon cycling. So far, a wide variety of advanced materials and electrode structures are developed to improve the long-term cyclability of alloying-type materials. This review provides fundamentals of anti-pulverization and cutting-edge concepts that aim to achieve high-performance alloying anodes for LIBs/SIBs from the viewpoint of architectural engineering. The recent progress on the effective strategies of nanostructuring, incorporation of carbon, intermetallics design, and binder engineering is systematically summarized. After that, the relationship between architectural design and electrochemical performance as well as the related charge-storage mechanisms is discussed. Finally, challenges and perspectives of alloying-type anode materials for further development in LIB/SIB applications are proposed.

4.
J Anim Ecol ; 90(3): 751-765, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33314075

RESUMO

Apposite conceptualization and measurement of resource variation is critical for understanding many issues in ecology, including ecological niches, persistence and distribution of populations, the structure of communities and population resilience to perturbations. We apply the nutritional geometry framework to conceptualize and quantify the responses of a temperate-living primate, the golden snub-nosed monkey Rhinopithecus roxellana to variation in resource quality and quantity and in nutrient requirements associated with seasonal environments. We present a geometric model distinguishing qualitative constraint, quantitative constraint and 'pseudo-constraint' whereby nutrient intakes resemble response to qualitative resource constraint but are in fact driven by variation in nutrient requirements. The model is applied to analyse nutrient intakes recorded in 164 full-day observations of monkeys from two populations, one wild and the other captive, across seasons. Additionally, we recorded the diet of a single animal over 32 consecutive days in the wild. Despite considerable differences in available resources, the captive and wild populations showed marked similarities in nutrient intakes, including indistinguishable amounts and ratios of ingested macronutrients during summer and autumn and strong year-round maintenance of protein compared to seasonally variable fat and carbohydrate intakes. These similarities suggest homeostatically regulated nutritional targets and provide reference points to identify factors driving population differences in macronutrient intake in winter and spring. Our framework enabled us to distinguish examples of quantitative, qualitative and 'pseudo-constraint'. We suggest that this approach can increase the resolution at which resource constraint is conceptualized and measured in ecological studies.


Assuntos
Colobinae , Presbytini , Animais , China , Dieta/veterinária , Estações do Ano
5.
Conserv Biol ; 35(6): 1787-1796, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34219272

RESUMO

A systematic understanding of dynamic animal extinction trajectories for different regions in a nation like China is critically important to developing practical conservation strategies. We explored historical and contemporary changes in terrestrial mammalian diversity to determine how diversity in each of the 5 regions in China has changed over time and to examine the conservation potential of these regions. We used records from databases on Pleistocene mammalian fossils and historical distribution records (1175-2020) for Primates (as a case study) to reconstruct evolutionary and historical distribution trajectories of the 11 orders of terrestrial mammals and to predict their prospective survival based on the national conservation strategy applied. The results indicated that since the Pleistocene, 4-5 mammalian orders have been lost in the northeast, 3 in central China, 2 along the coast, and 1 in the northwest. In the southwest, all 11 orders were maintained. Contemporarily, the coast and southwest had the highest and second-highest species densities. The southwest region and southeastern sections of the northwest region were the most historically and contemporarily diverse areas, which suggests that they should be the first priority for protected area (PA) designation. The central and coastal areas should be secondarily prioritized. In these 2 regions, conservation should focus on human coexistence with nature. Less attention should be paid to the PA in the northeast and western northwest because in these areas ecosystems are depauperate and the climate is harsh. Conservation in these areas should focus principally on avoiding further human encroachment on natural areas. Article impact statement: Historical and contemporary patterns of extinction can be a basis for mammalian conservation strategies.


Uso de la Distribución Histórica y Contemporánea de los Mamíferos en China para Orientar a la Conservación Resumen El entendimiento sistemático de las trayectorias de extinción dinámica de los animales para diferentes regiones en un país como en China es de importancia crítica para poder desarrollar estrategias de conservación prácticas. Exploramos los cambios históricos y contemporáneos en la diversidad de mamíferos terrestres para determinar cómo ha cambiado con el tiempo la diversidad en cada una de las cinco regiones de China y para examinar el potencial de conservación de aquellas regiones. Usamos registros tomados de bases de datos con información sobre los fósiles de mamíferos del Pleistoceno y registros de la distribución histórica (1175 - 2020) de los primates (como estudio de caso) para reconstruir las trayectorias de distribución históricas y contemporáneas de los once órdenes de mamíferos terrestres presentes en China. También utilizamos esta información para predecir la supervivencia potencial de estos órdenes con base en la estrategia nacional de conservación aplicada. Los resultados indicaron que, desde el Pleistoceno, entre cuatro y cinco órdenes de mamíferos se han perdido en el noreste de China, tres en la zona central, dos a lo largo de la costa y uno en el noroeste. En el suroeste del país se han mantenido los once órdenes. Actualmente, la costa y el suroeste tienen la primera y segunda densidad más alta de especies. La región del suroeste y las secciones al sureste de la región del noroeste son las áreas con la mayor diversidad histórica y contemporánea, lo que sugiere que deberían ser de primera prioridad para la designación de áreas protegidas (AP). Las áreas de la costa y el centro deberían ser las de segunda prioridad por la misma razón. En estas dos últimas regiones, la conservación debería enfocarse en la coexistencia entre los humanos y la naturaleza. Se les debería prestar una menor atención a las AP en el noreste y en la zona oeste del noroeste porque en estas áreas los ecosistemas son paupérrimos y el clima es hostil. La conservación en estas áreas debería enfocarse principalmente en evitar más invasiones humanas dentro de las áreas naturales.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , China , Mamíferos , Estudos Prospectivos
6.
Am J Phys Anthropol ; 173(4): 630-642, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32918292

RESUMO

OBJECTIVES: Social animals often have dominance hierarchies, with high rank conferring preferential access to resources. In primates, competition among males is often assumed to occur predominantly over reproductive opportunities. However, competition for food may occur during food shortages, such as in temperate species during winter. Higher-ranked males may thus gain preferential access to high-profitability food, which would enable them to spend longer engaged in activities other than feeding. MATERIALS AND METHODS: We performed a field experiment with a breeding band of golden snub-nosed monkeys, a species that lives in a multi-level society in high-altitude forests in central China. We provisioned monkey's high-profitability food during winter when natural foods are limited, and then recorded the times individual adult males spent engaged in different behaviors. RESULTS: Higher-ranking males spent less time feeding overall and fed on provisioned foods at a higher rate than lower-ranking males. Higher-ranking males therefore had more time to spend on alternative behaviors. We found no significant difference according to rank in times spent moving or resting. However, high-ranking males spend significantly longer on affiliative behaviors with other members of their social sub-units, especially grooming and being groomed, behaviors known to promote social cohesion in primates. DISCUSSION: We show that preferential access to high-profitability foods likely relaxes time-budget constraints to higher-ranking males. High-ranking males thus spend more time on non-feeding activities, especially grooming, which may enhance social cohesion within their social sub-unit. We discuss the potential direct and indirect benefits to high-ranking males associated with preferential access to high-value food during winter.


Assuntos
Colobinae/fisiologia , Comportamento Competitivo/fisiologia , Comportamento Alimentar/fisiologia , Predomínio Social , Animais , Antropologia Física , China , Feminino , Asseio Animal/fisiologia , Masculino
7.
Am J Primatol ; 82(7): e23142, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32452078

RESUMO

Depicting a taxonomic group's evolutionary trajectory as a function of changes in the geographical landscape and its historical distribution is critical for constructing informed conservation strategies. Based on fossil sites from the Pliocene to the Holocene, and historical records since 1175 AD, we established macaques' dispersal pathways into and through China. These routes include internal pathways starting from the southeast corner of the Qinghai-Tibet Plateau and Mts. Hengduan in western China, and the routes through the estuaries of the three major rivers (Yangtze, Yellow, and Pearl). Our results indicate that macaques used the three rivers and avoided the higher elevation of the plateaus to promote their radiation. They occupied the whole mainland and islands in the Pleistocene and experienced shrunken distribution in the Holocene due to climate changes and human-induced activities. A prominent China-wide reduction occurred between 1817 and 1917; and a remarkable retraction from central China happened between 1918 and 2018 following further eco-social development and human expansion in central China, particularly since the second half of the last century. Starting in 1175 there was a restriction of range to higher altitudes, so that macaques have contracted their range to the west, and the Qinghai-Tibet Plateau and Mts. Hengduan have become an important sanctuary. We predict that if the current climate and human-induced changes are not reversed by decisive conservation actions, macaques in east and central China will likely be extinct in the near future.


Assuntos
Evolução Biológica , Macaca/classificação , Filogeografia , Altitude , Distribuição Animal , Animais , China , Mudança Climática , Conservação dos Recursos Naturais , Fósseis , Atividades Humanas
8.
Folia Primatol (Basel) ; 91(6): 669-687, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32126549

RESUMO

With 60% of all primate species now threatened with extinction and many species only persisting in small populations in forest fragments, conservation action is urgently needed. But what type of action? Here we argue that restoration of primate habitat will be an essential component of strategies aimed at conserving primates and preventing the extinctions that may occur before the end of the century and propose that primates can act as flagship species for restoration efforts. To do this we gathered a team of academics from around the world with experience in restoration so that we could provide examples of why primate restoration ecology is needed, outline how primates can act as flagship species for restoration efforts of tropical forest, review what little is known about how primate populations respond to restoration efforts, and make specific recommendations of the next steps needed to make restoration of primate populations successful. We set four priorities: (1) academics must effectively communicate both the value of primates and the need for restoration; (2) more research is needed on how primates contribute to forest restoration; (3) more effort must be put into Masters and PhD level training for tropical country nationals; and finally (4) more emphasis is needed to monitor the responses of regenerating forest and primate populations where restoration efforts are initiated. We are optimistic that populations of many threatened species can recover, and extinctions can be prevented, but only if concerted large-scale efforts are made soon and if these efforts include primate habitat restoration.


Assuntos
Conservação dos Recursos Naturais/métodos , Florestas , Primatas , Animais , Ecossistema , Recuperação e Remediação Ambiental , Extinção Biológica
9.
Proc Biol Sci ; 286(1916): 20192047, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31797732

RESUMO

Research is a highly competitive profession where evaluation plays a central role; journals are ranked and individuals are evaluated based on their publication number, the number of times they are cited and their h-index. Yet such evaluations are often done in inappropriate ways that are damaging to individual careers, particularly for young scholars, and to the profession. Furthermore, as with all indices, people can play games to better their scores. This has resulted in the incentive structure of science increasingly mimicking economic principles, but rather than a monetary gain, the incentive is a higher score. To ensure a diversity of cultural perspectives and individual experiences, we gathered a team of academics in the fields of ecology and evolution from around the world and at different career stages. We first examine how authorship, h-index of individuals and journal impact factors are being used and abused. Second, we speculate on the consequences of the continued use of these metrics with the hope of sparking discussions that will help our fields move in a positive direction. We would like to see changes in the incentive systems, rewarding quality research and guaranteeing transparency. Senior faculty should establish the ethical standards, mentoring practices and institutional evaluation criteria to create the needed changes.


Assuntos
Autoria , Pesquisa , Academias e Institutos , Fator de Impacto de Revistas
10.
BMC Evol Biol ; 18(1): 29, 2018 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-29534675

RESUMO

BACKGROUND: Maintaining variation in immune genes, such as those of the major histocompatibility complex (MHC), is important for individuals in small, isolated populations to resist pathogens and parasites. The golden snub-nosed monkey (Rhinopithecus roxellana), an endangered primate endemic to China, has experienced a rapid reduction in numbers and severe population fragmentation over recent years. For this study, we measured the DRB diversity among 122 monkeys from three populations in the Qinling Mountains, and estimated the relative importance of different agents of selection in maintaining variation of DRB genes. RESULTS: We identified a total of 19 DRB sequences, in which five alleles were novel. We found high DRB variation in R. roxellana and three branches of evidence suggesting that balancing selection has contributed to maintaining MHC polymorphism over the long term in this species: i) different patterns of both genetic diversity and population differentiation were detected at MHC and neutral markers; ii) an excess of non-synonymous substitutions compared to synonymous substitutions at antigen binding sites, and maximum-likelihood-based random-site models, showed significant positive selection; and iii) phylogenetic analyses revealed a pattern of trans-species evolution for DRB genes. CONCLUSIONS: High levels of DRB diversity in these R. roxellana populations may reflect strong selection pressure in this species. Patterns of genetic diversity and population differentiation, positive selection, as well as trans-species evolution, suggest that pathogen-mediated balancing selection has contributed to maintaining MHC polymorphism in R. roxellana over the long term. This study furthers our understanding of the role pathogen-mediated balancing selection has in maintaining variation in MHC genes in small and fragmented populations of free-ranging vertebrates.


Assuntos
Colobinae/genética , Genética Populacional , Cadeias beta de HLA-DR/genética , Complexo Principal de Histocompatibilidade/genética , Polimorfismo Genético , Seleção Genética , Alelos , Animais , Sequência de Bases , China , Éxons/genética , Frequência do Gene/genética , Geografia , Funções Verossimilhança , Repetições de Microssatélites/genética , Filogenia , Especificidade da Espécie
11.
Am J Primatol ; 80(4): e22755, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29635833

RESUMO

There is a great deal of spatial and temporal variation in the availability and nutritional quality of foods eaten by animals, particularly in temperate regions where winter brings lengthy periods of leaf and fruit scarcity. We analyzed the availability, dietary composition, and macronutrients of the foods eaten by the northern-most golden snub-nosed monkey (Rhinopithecus roxellana) population in the Qinling Mountains, China to understand food choice in a highly seasonal environment dominated by deciduous trees. During the warm months between April and November, leaves are consumed in proportion to their availability, while during the leaf-scarce months between December and March, bark and leaf/flower buds comprise most of their diet. When leaves dominated their diet, golden snub-nosed monkeys preferentially selected leaves with higher ratios of crude protein to acid detergent fiber. While when leaves were less available, bark and leaf/flower buds that were high in nonstructural carbohydrates and energy, and low in acid detergent fiber were selected. Southern populations of golden snub-nosed monkey can turn to eating lichen, however, the population studied here in this lichen-absent area have adapted to their cool deciduous habitat by instead consuming buds and bark. Carbohydrate and energy rich foods appear to be the critical resources required for the persistence of this species in temperate habitat. The dietary flexibility of these monkeys, both among seasons and populations, likely contributes to their wide distribution over a range of habitats and environments.


Assuntos
Colobinae/fisiologia , Dieta/veterinária , Estações do Ano , Animais , China , Comportamento Alimentar , Feminino , Preferências Alimentares , Masculino , Valor Nutritivo , Componentes Aéreos da Planta/química , Árvores
12.
Sensors (Basel) ; 17(8)2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28820496

RESUMO

Recently, the simultaneous wireless information and power transfer (SWIPT) technique has been regarded as a promising approach to enhance performance of wireless sensor networks with limited energy supply. However, from a green communication perspective, energy efficiency optimization for SWIPT system design has not been investigated in Wireless Rechargeable Sensor Networks (WRSNs). In this paper, we consider the tradeoffs between energy efficiency and three factors including spectral efficiency, the transmit power and outage target rate for two different modes, i.e., power splitting (PS) and time switching modes (TS), at the receiver. Moreover, we formulate the energy efficiency maximization problem subject to the constraints of minimum Quality of Service (QoS), minimum harvested energy and maximum transmission power as non-convex optimization problem. In particular, we focus on optimizing power control and power allocation policy in PS and TS modes to maximize energy efficiency of data transmission. For PS and TS modes, we propose the corresponding algorithm to characterize a non-convex optimization problem that takes into account the circuit power consumption and the harvested energy. By exploiting nonlinear fractional programming and Lagrangian dual decomposition, we propose suboptimal iterative algorithms to obtain the solutions of non-convex optimization problems. Furthermore, we derive the outage probability and effective throughput from the scenarios that the transmitter does not or partially know the channel state information (CSI) of the receiver. Simulation results illustrate that the proposed optimal iterative algorithm can achieve optimal solutions within a small number of iterations and various tradeoffs between energy efficiency and spectral efficiency, transmit power and outage target rate, respectively.

13.
Am J Primatol ; 78(11): 1137-1148, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27383018

RESUMO

Although the evolutionary history of primates in China dates to the Eocene, and includes major radiations of lorisids, hominoids, cercopithecines, and colobines during the Miocene, Pliocene, and Pleistocene, extensive human-induced habitat change and deforestation over the past few centuries has resulted in 22 of 25 extant species listed as threatened or endangered, and two species of gibbons extirpated in the last few years. This commentary briefly reviews factors that have contributed to the decline of primates in China over the past 400 years, and in particular how major social events and economic development in modern China have resulted in unsustainable environmental change. In response, we describe our efforts to develop a strategic scientific, educational and conservation partnership in China, focusing on primates, in which GIS technology will be used to integrate geographical profiles, climatic information, and changes in land use patterns and human and nonhuman primate distributions to highlight issues of immediate concern and to develop priority-based conservation solutions. Our goal is to evaluate how human-induced environmental change has impacted primates over time and to predict the likelihood of primate population extinctions in the near future. This model represents an early warning system that will be widely available to the Chinese government, public, educational institutions, researchers, and NGOs through social media and educational videos in order to arouse public awareness and promote wildlife conservation. We encourage colleagues across a broad range of academic disciplines, political ideologies, and the public to help move this strategy into reality, the sooner the better. Am. J. Primatol. 78:1137-1148, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Primatas , Animais , China , Geografia , Humanos , Modelos Teóricos
14.
Am J Phys Anthropol ; 156(4): 606-13, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25448828

RESUMO

A small number of mammalian species live in a modular or multilevel society in which several individual social/reproductive units called one-male units (OMUs) are embedded within a large cohesive band. Factors that affect band composition and stability are poorly understood. In this study we examined the role of kinship in the formation and maintenance of a multilevel society in an endangered population of golden snub-nosed monkeys (Rhinopithecus roxellana). From 2005 to 2011, we obtained genetic samples from 86 individuals (including 88.9% of leader males and 80.5% of adult females) living in a band of 8-10 OMUs. We used microsatellite genotyping to identify patterns of relatedness and individual transfer. We found that adult females residing in the same OMU were more closely related to each other than to a random set of females drawn from the band and that females tended to disperse into OMUs that contained female relatives. In addition, adult females who transferred were not more closely related to their previous leader male than to the leader male of their new OMU. These results support the contention that kin bonds contribute importantly to the formation and stability of this primate multilevel society by influencing a female's decision to remain in her current OMU, or during transfer, which new OMU to enter.


Assuntos
Colobinae/genética , Técnicas de Genotipagem/métodos , Repetições de Microssatélites/genética , Animais , Feminino , Masculino , Comportamento Social , Predomínio Social
15.
Folia Primatol (Basel) ; 86(5): 446-54, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26575480

RESUMO

This study analyzed conflict and postconflict (PC) conciliation between males and females within one-male breeding units in Sichuan snub-nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains, China. The PC matched-control and time rule methods were used to collect and analyze data recorded from September 2013 to June 2014. The conciliatory tendency among individuals following conflict was 82.07%, and affiliation occurred within a few minutes after the conflict, which was not significantly different between mating and nonmating seasons. The PC conciliation scenarios were different from those reported from captivity. Lumbar hold and grooming were the most common expressions in reconciliation. In addition, bystander affiliation was uniquely found, which may be associated with the more terrestrial locomotion of R. roxellana, compared with other colobines.


Assuntos
Colobinae/fisiologia , Comportamento Social , Animais , Comportamento Animal , China , Colobinae/psicologia , Conflito Psicológico , Feminino , Asseio Animal , Masculino , Estações do Ano
16.
Folia Primatol (Basel) ; 85(6): 343-57, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25612509

RESUMO

Due to their rich animal diversity and the presence of rare and endemic species, the Qinling Mountains are listed as a significant global biodiversity area. The Sichuan snub-nosed monkey (Rhinopithecus roxellana) has been distributed in this area since the Middle Pleistocene. Due to the gradual encroachment of humans into their habitat, both the distribution range and population sizes of R. roxellana have significantly decreased. Based on literature research as well as field and questionnaires, we investigated the influence of human activities on R. roxellana distribution in the Qinling Mountains. Human activity within the habitat of R. roxellana began in the Stone and Bronze Ages, though initially it had no significant influence on its populations. When China entered the Iron Age, however, different historical and social periods had a considerable impact on R. roxellana distribution. Although national and provincial level governments introduced strict protection policies with the establishment of the People's Republic of China in 1949, human activities continued to influence R. roxellana distribution. Since the launch of the Natural Forest Protection Project across the Qinling Mountains in 1999, the quality of R. roxellana habitat has shown marked improvement. This research will help promote the survival and conservation of the Sichuan snub-nosed monkey in the Qinling Mountains.


Assuntos
Distribuição Animal , Colobinae/fisiologia , Conservação dos Recursos Naturais , Ecossistema , Animais , China , Atividades Humanas , Humanos , Densidade Demográfica
17.
Artigo em Inglês | MEDLINE | ID: mdl-38896514

RESUMO

The emergence of 5G technology has enabled the development of Metaverse applications that provide users with immersive experiences through augmented reality (AR) devices, and the integration of federated learning (FL) with the Metaverse AR (MAR) systems can enable many edge intelligence services in 5G. However, the presence of nonindependent and identically distributed (Non-IID) data across all AR users' devices, coupled with limited edge communication resources, makes it challenging to achieve human-centric Metaverse-related applications such as target detection or image classification that combine virtual content with real-world. To address these challenges, we propose a novel adaptive resource-efficient Metaverse-based FL (AMFL) algorithm for AR applications that mitigates the negative effect of Non-IID data and reduces resource costs as well as improves the quality of experience (QoE). We first analyze the impact of wireless communication factors such as CPU frequency, bandwidth, and transmission power on FL training performance by a toy example in the MAR systems. Based on this analysis, furthermore, we establish a Non-IID degree, model accuracy, and resource consumption-related QoE maximization problem under given resource budgets, which is a stochastic optimization problem with strongly coupled variables, including bandwidth, CPU frequency, and transmission power. Guided by the theoretical analysis, to solve this issue, AMFL employs a deep reinforcement learning (DRL)-based method to adaptively allocate resources. Numerical results demonstrate that AMFL can significantly improve the QoE by up to 30.28 % , and reduce communication round and energy costs by up to 81.08 % and 72.20 % , respectively, even under the worst Non-IID case, compared to benchmarks.

18.
J Colloid Interface Sci ; 673: 616-627, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38897063

RESUMO

Oxygen evolution reaction (OER) is the efficiency limiting half-reaction in water electrolysis for green hydrogen production due to the 4-electron multistep process with sluggish kinetics. The electrooxidation of thermodynamically more favorable organics accompanied by CC coupling is a promising way to synthesize value-added chemicals instead of OER. Efficient catalyst is of paramount importance to fulfill such a goal. Herein, a molybdenum iron carbide-copper hybrid (Mo2C-FeCu) was designed as anodic catalyst, which demonstrated decent OER catalytic capability with low overpotential of 238 mV at response current density of 10 mA cm-2 and fine stability. More importantly, the Mo2C-FeCu enabled electrooxidation assisted aldol condensation of phenylcarbinol with α-H containing alcohol/ketone in weak alkali electrolyte to selective synthesize cinnamaldehyde/benzalacetone at reduced potential. The hydroxyl and superoxide intermediate radicals generated at high potential are deemed to be responsible for the electrooxidation of phenylcarbinol and aldol condensation reactions to afford cinnamaldehyde/benzalacetone. The current work showcases an electrochemical-chemical combined CC coupling reaction to prepare organic chemicals, we believe more widespread organics can be synthesized by tailored electrochemical reactions.

19.
J Hazard Mater ; 476: 134938, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38901262

RESUMO

Microplastics (MPs) and heavy metals (HMs) are important pollutants in terrestrial ecosystems. In particular, the "island" landscape's weak resistance makes it vulnerable to pollution. However, there is a lack of research on MPs and HMs in island landscapes. Therefore, we used Helan Mountain as the research area. Assess the concentrations, spatial distribution, ecological risks, sources, and transport of MPs and HMs in the soil and blue sheep (Pseudois nayaur) feces. Variations in geographical distribution showed a connection between human activity and pollutants. Risk assessment indicated soil and wildlife were influenced by long-term pollutant polarization and multi-element inclusion (Igeo, Class I; PHI, Class V; RI (MPs), 33 % Class II, and 17 % Class IV; HI = 452.08). Source apportionment showed that tourism and coal combustion were the primary sources of pollutants. Meanwhile, a new coupling model of PMF/Risk was applied to quantify the source contribution of various risk types indicated transportation roads and tourism sources were the main sources of ecological and health risks, respectively. Improve the traceability of pollution source risks. Furthermore, also developed a novel tracing model for pollutant transportation, revealing a unique "source-sink-source" cycle in pollutant transportation, which provides a new methodological framework for the division of pollution risk areas in nature reserves and the evaluation of spatial transport between sources and sinks. Overall, this study establishes a foundational framework for conducting comprehensive risk assessments and formulating strategies for pollution control and management.


Assuntos
Ecossistema , Monitoramento Ambiental , Fezes , Metais Pesados , Microplásticos , Microplásticos/análise , Metais Pesados/análise , Animais , Medição de Risco , Fezes/química , Poluentes do Solo/análise , Ovinos , China
20.
Integr Zool ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597117

RESUMO

Golden snub-nosed monkeys show inconsistent frequency of placentophagy between wild and captive populations, with almost all births in the wild but around half of the births in captivity accompanied by the female's consumption of placenta. This aligns with nutritional demands-driven placentophagy, as captive populations are generally under less nutritional constraints for breeding females than the wild population. Placentophagy is probably adaptive in the wild and under positive selection due to nutritional benefits to both mothers and infants.

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