Recent advances in our understanding of avian chemical communication have highlighted the importance of olfaction in many aspects of avian life.Prior studies investigating predator avoidance behaviors in response to p...Recent advances in our understanding of avian chemical communication have highlighted the importance of olfaction in many aspects of avian life.Prior studies investigating predator avoidance behaviors in response to predator odor cues have produced mixed results across species and contexts.Here we assess if a community of birds in eastern Pennsylvania displays avoidance behaviors towards predator odor cues in a natural foraging setting.We use clay caterpillars to measure foraging activity by birds in the presence of predator(bobcat)urine,non-predator(rabbit)urine,and water controls in two different environmental contexts(field vs.forest).Although we detected a weak trend for birds to forage less at predator urine-treated sites,we found no significant difference in avian foraging between the site types.We did find that foraging rates between environmental contexts changed significantly over the course of the experiment,with forest sites showing decreasing foraging rates and field sites showing increasing foraging rates.Our results reinforce the published literature that avoidance of predator odors by birds may not be ubiquitous across contexts and species.展开更多
Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi...Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi-encing increased aridity.Although numerous studies have investigated birds’responses to drought,the emphasis has primarily been on landbirds.Drought can significantly alter the wetland environments that waterbirds inhabit,but the response of waterbirds to drought remains understudied.In this study,we surveyed the distri-bution and behavior of Oriental Storks(Ciconia boyciana)in Poyang Lake,which is the largest freshwater lake in China.Results indicate that drought-induced catchment areas at the lowest water level limited the total popu-lation size of Oriental Storks in the sub-lakes.Sub-lakes with large catchment areas at the lowest water level demonstrated a capacity to support a larger population of wintering Oriental Storks.Over time,Oriental Storks exhibited a gradual concentration in Changhu Lake,characterized by larger catchments,after resource depletion in sub-lakes with smaller catchments.Additionally,the duration of Oriental Storks’vigilance and moving be-haviors decreased significantly compared with that observed before the drought.After the drought,Oriental Storks increased their foraging efforts,as evidenced by increased presence in deeper water and reaching their heads and necks into deeper water to forage,higher search rates,but lower foraging rates.In accordance with area-restricted search theory,reductions in habitat quality resulting from drought,including extensive fish die-offs,forced Oriental Storks to increase their foraging efforts.Sustaining a specific water area in sub-lakes during droughts can preserve resource availability,which is crucial for the conservation of Oriental Storks.Imple-menting measures such as water level control and micro-modification of lake bottoms in sub-lakes might mitigate the impact of drought on the piscivorous Oriental Storks.展开更多
Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell ...Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell migration,and cell–cell interactions.One of the fundamental characteristics of cell movement is the specific distribution of cell speed,containing valuable information that still requires comprehensive understanding.This article investigates the distribution of mean velocities along cell trajectories,with a focus on optimizing the efficiency of cell food search in the context of the entire colony.We confirm that the specific velocity distribution in the experiments corresponds to an optimal search efficiency when spatial weighting is considered.The simulation results indicate that the distribution of average velocity does not align with the optimal search efficiency when employing average spatial weighting.However,when considering the distribution of central spatial weighting,the specific velocity distribution in the experiment is shown to correspond to the optimal search efficiency.Our simulations reveal that for any given distribution of average velocity,a specific central spatial weighting can be identified among the possible central spatial weighting that aligns with the optimal search strategy.Additionally,our work presents a method for determining the spatial weights embedded in the velocity distribution of cell movement.Our results have provided new avenues for further investigation of significant topics,such as relationship between cell behavior and environmental conditions throughout their evolutionary history,and how cells achieve collective cooperation through cell-cell communication.展开更多
Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to...Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to maximize energy gains and cope with the intensified challenges of parenting and self-maintenance.Such tradeoff may stem from the heterogeneity of food resources and the constraints of central place foraging.Nevertheless,abundant marine productivity could alleviate the energy limitation for seabirds,resulting in a consistent foraging approach.Here,we investigated the foraging strategy during the breeding season of a cryptic small-sized seabird,Swinhoe’s Storm-petrel(Hydrobates monorhis),in the Yellow Sea,a productive marginal sea of the Northwest Pacific.Using GPS tracking,we evaluated habitat preference,quantified the foraging strategy,and tested if environmental conditions and individual traits influence foraging trips.We found that Swinhoe’s Storm-petrels preferred nearshore areas with shallow water and engaged in primarily short foraging trips.Distinctive southeastward and southwestward strategies emerged when combining trip metrics,including foraging direction,duration,and maximum distance.The bathymetry,proximity to the coastline,and sea surface temperature differed in two foraging strategies.Foraging strategies exhibited flexibility between individuals,potentially explained by wing morphology,in which longer-winged birds are more likely to embark on longer-distance foraging trips.These findings highlight the impact of environmental factors and individual traits on seabirds’foraging decisions in productive marginal sea ecosystems.Our study also provides valuable insights into the foraging ecology of this Asian endemic storm-petrel.展开更多
In order to play a positive role of decentralised wind power on-grid for voltage stability improvement and loss reduction of distribution network,a multi-objective two-stage decentralised wind power planning method is...In order to play a positive role of decentralised wind power on-grid for voltage stability improvement and loss reduction of distribution network,a multi-objective two-stage decentralised wind power planning method is proposed in the paper,which takes into account the network loss correction for the extreme cold region.Firstly,an electro-thermal model is introduced to reflect the effect of temperature on conductor resistance and to correct the results of active network loss calculation;secondly,a two-stage multi-objective two-stage decentralised wind power siting and capacity allocation and reactive voltage optimisation control model is constructed to take account of the network loss correction,and the multi-objective multi-planning model is established in the first stage to consider the whole-life cycle investment cost of WTGs,the system operating cost and the voltage quality of power supply,and the multi-objective planning model is established in the second stage.planning model,and the second stage further develops the reactive voltage control strategy of WTGs on this basis,and obtains the distribution network loss reduction method based on WTG siting and capacity allocation and reactive power control strategy.Finally,the optimal configuration scheme is solved by the manta ray foraging optimisation(MRFO)algorithm,and the loss of each branch line and bus loss of the distribution network before and after the adoption of this loss reduction method is calculated by taking the IEEE33 distribution system as an example,which verifies the practicability and validity of the proposed method,and provides a reference introduction for decision-making for the distributed energy planning of the distribution network.展开更多
Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their...Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM ha<sup>-1</sup>) and contributed the most total N (167 kg∙ha<sup>-1</sup>) and total C (3043 kg∙ha<sup>-1</sup>) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea produced 8.41 t DM ha<sup>-1</sup> with a total N yield of 319 kg N ha<sup>-1</sup> and total C production of 3835 kg C ha<sup>-1</sup>. The WSL treatments had only small effects on rye forage yield and N concentration, possibly due to mineralization of N from a large SOC pool already in place. The CSL treatments also had only minimal effects on sorghum-sudangrass forage production. Winter pea, arrow leaf and crimson clover were productive cool season legumes and could be useful as green manure crops. Mungbean and cowpea (Vigna unguiculata [L.] Walp.) were highly productive warm season legumes but may include more production risk in green manure systems due to soil moisture competition.展开更多
A critical function of animal movement is to maximize access to essential resources in temporally fluctuating and spatially heterogeneous environments.Seasonally mediated resource fluctuations may influence animal mov...A critical function of animal movement is to maximize access to essential resources in temporally fluctuating and spatially heterogeneous environments.Seasonally mediated resource fluctuations may influence animal movements,enabling them to track changing resource distributions,resulting in annual migration patterns.The conservation-dependent giant panda(Ailuropoda melanoleuca) displays seasonal movement patterns;however,the key factor driving these seasonal migration patterns remains poorly understood.Here,we used GPS tracking collars to monitor the movements of six giant pandas over a 12-year period across different elevations,and performed statistical analysis of seasonal migration directions,routes,habitat revisitation,home range overlap,first arrival events,and stability.Our results revealed a compelling pattern of seasonal migrations that facilitated the ability of the pandas to forage at the appropriate time and place to maximize nutritional intake.Our results indicated that pandas utilize spatial memory to locate reliable food resources,as evidenced by their annual return to the same or similar winter and summer home ranges and the consistently maintained percentage of home range overlap.These novel insights into giant panda foraging and movement ecology not only enhance our understanding of its ability to adapt to nutritionally poor dietary resources but also provide important information for the development of resource utilization-based protection and management strategies.展开更多
Background Previous investigations into the effect of dietary forage on calf performance have been inconsistent,and there is a paucity of information exploring the effect of age on the growth performance and ruminatio...Background Previous investigations into the effect of dietary forage on calf performance have been inconsistent,and there is a paucity of information exploring the effect of age on the growth performance and rumination of calves.Eighty-four female Holstein calves(41.5±4.2 kg)were enrolled at birth,a subset of the calves were fed calf starter only(CON,n=21)while the rest(n=63)were classified into three treatment groups:the early(EHAY,n=26,5.1±0.8 d),the middle(MHAY,n=21,7.9±0.8 d)and the late(LHAY,n=16,12.1±1.4 d)hay consumers.The short-term effect of the age at first forage consump-tion(AFF)on calves’feed intake was monitored until d 84.In addition,the long-term effects of AFF on body weight,structural growth and rumination behavior were recorded until d 196.Rumen samples were collected on d 1,7,35,84 and 196 to ana-lyze the rumen fermentation,while fecal samples were collected from d 78 to 84 to estimate digestibility parameters.Results Treatment had no effect on feed intake.While,the EHAY calves tended to have lower BW and ADG compared to LHAY and CON calves.Several total-tract apparent digestibility parameters and digestible nutrients intake were significantly lower in EHAY calves compared with CON and LHAY calves.Calves in the EHAY group tended to begin ruminating ealier,while CON calves were the latest(12.3 vs.15.5 days of age).A treatment and time interaction was present for rumination time due to greater rumination in calves consuming hay compared to CON calves in week 10 to 12,the differences in rumination disappeared afterwards,no long-lasting significant differences in the rumina-tion and rumen fermentation parameters were found between treatments.Conclusions In conclusion,this study showed that hay consumption earlier in life(in the first week,around 5 days of life)could negatively affect the growth of the calf in the short and long term.Compared to consuming hay from the second week(around 12 days of life)or feeding concentrate only without hay,starting to consume hay from the first week could compromise nutrient digestibility and digestible nutrient intake independent of developing rumination behaviour and rumen fermentation.展开更多
A significant advantage of medical image processing is that it allows non-invasive exploration of internal anatomy in great detail.It is possible to create and study 3D models of anatomical structures to improve treatm...A significant advantage of medical image processing is that it allows non-invasive exploration of internal anatomy in great detail.It is possible to create and study 3D models of anatomical structures to improve treatment outcomes,develop more effective medical devices,or arrive at a more accurate diagnosis.This paper aims to present a fused evolutionary algorithm that takes advantage of both whale optimization and bacterial foraging optimization to optimize feature extraction.The classification process was conducted with the aid of a convolu-tional neural network(CNN)with dual graphs.Evaluation of the performance of the fused model is carried out with various methods.In the initial input Com-puter Tomography(CT)image,150 images are pre-processed and segmented to identify cancerous and non-cancerous nodules.The geometrical,statistical,struc-tural,and texture features are extracted from the preprocessed segmented image using various methods such as Gray-level co-occurrence matrix(GLCM),Histo-gram-oriented gradient features(HOG),and Gray-level dependence matrix(GLDM).To select the optimal features,a novel fusion approach known as Whale-Bacterial Foraging Optimization is proposed.For the classification of lung cancer,dual graph convolutional neural networks have been employed.A com-parison of classification algorithms and optimization algorithms has been con-ducted.According to the evaluated results,the proposed fused algorithm is successful with an accuracy of 98.72%in predicting lung tumors,and it outper-forms other conventional approaches.展开更多
Pallid Swifts(Apus pallidus),as other swifts,are birds extremely adapted to an aerial lifestyle,showing unique adaptations that allow them to fly almost continuously.The diet of these non-stopping high-altitudinal aer...Pallid Swifts(Apus pallidus),as other swifts,are birds extremely adapted to an aerial lifestyle,showing unique adaptations that allow them to fly almost continuously.The diet of these non-stopping high-altitudinal aerial birds has been mostly studied through techniques that fail to produce highly resolved prey identifications,and for that have been replaced by molecular techniques,such as DNA metabarcoding.Faecal samples of Pallid Swifts were monthly collected from a colony in the north of Portugal during the breeding season.DNA from the faecal samples was used to sex the birds and to identify the arthropods present in the diet through DNA metabarcoding.From the detected prey items,74 families were identified belonging to 16 orders,with Hymenoptera and Hemiptera being the most frequently consumed.There were seasonal variations in diet richness,composition and prey size.Regarding the diet of males and females,although no differences were found between the diet of males and females in terms of composition and richness,there were differences in the size of arthropods preyed by the different sexes,with males feeding on larger arthropods.The large seasonal variation in Pallid Swifts’diet during the breeding season is probably a result of spatiotemporal variation in aerial prey,of which swifts likely predate opportunistically.Although no significant differences were detected in diet richness and composition between sexes,the fact that males consumed larger prey may suggest the existence of sexual dietary segregation in this group of birds.At last,several pest species were found in these swifts’diet,which,if studied through DNA metabarcoding,can be used to monitor small arthropods,including airborne pests.展开更多
Throughout evolutionary history,animals are finely tuned to adjust their behaviors corresponding to environmental variations.Behavioral flexibility represents an important component of a species'adaptive capacity ...Throughout evolutionary history,animals are finely tuned to adjust their behaviors corresponding to environmental variations.Behavioral flexibility represents an important component of a species'adaptive capacity in the face of rapid anthropogenetic environmental change,and knowledge of animal behaviors is increasingly recognized in conservation biology.In aquatic ecosystem,variation of water depth is a key factor affecting the availability of food;thus,the foraging behaviors of many waterbirds,especially piscivores.In this study,we compared the foraging behaviors of the Scaly-sided Merganser(Mergus squamatus),an endangered migratory diving duck endemic to East Asia,in habitats with different water depths(Shallow waters:0–40 cm;Deep waters:40–300 cm),using video camera records obtained from the known wintering sites during three winters from 2018 to 2020.Further,the energy expenditure of foraging behavior profile and energy intake based on fish sizes were calculated to study the foraging energetics.In total,200 effective video footages that contained 1086 min with 17,995 behaviors and 163 events of catching fish were recorded.Results showed that:1)time length for fishing(including eye-submerging,head-dipping,diving and food handling)of M.squamatus in shallow waters was significantly more than in deep waters;2)M.squamatuss spent significantly more time for preparing(including vigilance,preening and swimming)in deep waters than in shallow waters;3)the mean catch rate was 0.28 fish/min in shallow waters,which is significantly higher than the value of 0.13 fish/min in deep waters;4)despite the distinct foraging behavior profiles and energy intakes,M.squamatus showed similar energetics in shallow and deep waters.We concluded that M.squamatus is a good example of behavioral flexibility that aligns with expectations of optimal foraging theory,in that it behaves in accordance to resource availability in different environments,resulting in high foraging efficiency.展开更多
At present,the traditional channel estimation algorithms have the disadvantages of over-reliance on initial conditions and high complexity.The bacterial foraging optimization(BFO)-based algorithm has been applied in w...At present,the traditional channel estimation algorithms have the disadvantages of over-reliance on initial conditions and high complexity.The bacterial foraging optimization(BFO)-based algorithm has been applied in wireless communication and signal processing because of its simple operation and strong self-organization ability.But the BFO-based algorithm is easy to fall into local optimum.Therefore,this paper proposes the quantum bacterial foraging optimization(QBFO)-binary orthogonal matching pursuit(BOMP)channel estimation algorithm to the problem of local optimization.Firstly,the binary matrix is constructed according to whether atoms are selected or not.And the support set of the sparse signal is recovered according to the BOMP-based algorithm.Then,the QBFO-based algorithm is used to obtain the estimated channel matrix.The optimization function of the least squares method is taken as the fitness function.Based on the communication between the quantum bacteria and the fitness function value,chemotaxis,reproduction and dispersion operations are carried out to update the bacteria position.Simulation results showthat compared with other algorithms,the estimationmechanism based onQBFOBOMP algorithm can effectively improve the channel estimation performance of millimeter wave(mmWave)massive multiple input multiple output(MIMO)systems.Meanwhile,the analysis of the time ratio shows that the quantization of the bacteria does not significantly increase the complexity.展开更多
Drivers of bird niche separation in temperate primeval forests have not yet been determined,due to the low number of intact forest sites.Here,we analyzed the general patterns of niche usage on trees by birds’assembla...Drivers of bird niche separation in temperate primeval forests have not yet been determined,due to the low number of intact forest sites.Here,we analyzed the general patterns of niche usage on trees by birds’assemblages.We tested how tree species affect the sharing of space in an assemblage of birds and their level of specialization.We conducted our study in the Białowieża primeval forest(NE Poland).During two breeding seasons,we observed bird positions on trees,divided into three vertical and six horizontal zones in 768 observation points.Based on the interaction networks framework we calculated the Kullback-Leibler distance d′as a metric of species specialization and the resource range RR index,which estimates the species’specificity based on the fraction of space utilized with a non-zero performance.The d′index was the highest in the lower understory for all parts of the tree on the basis of the position from the trunk.The RR index was the highest in the lower understory for all parts based on the position from the trunk.Regarding the tree species,the lowest d′index was observed in all tree species together,and hornbeam,whereas the highest in oak.At the tree species level,the RR index was the lowest for hornbeam.We show tree species importance in forest space sharing in the case of bird assemblages.Hornbeam,alder,and spruce are universal species that were used by birds almost entirely.In contrast,oak,lime,and maple were only partially used.Tree species with less complex structures could shape bird assemblages,as they could offer birds much fewer niches to realize.Therefore,we showed that high specialization and niche separation are drivers of high bird diversity.Consequently maintaining a diverse stand structure is crucial for biodiversity conservation.展开更多
Animals that live in seasonal environments adjust their reproduction cycle to optimize seasonal forage quality.Giant pandas(Ailuropoda melanoleuca)are seasonal altitudinal migrants that feed on bamboo shoots and leave...Animals that live in seasonal environments adjust their reproduction cycle to optimize seasonal forage quality.Giant pandas(Ailuropoda melanoleuca)are seasonal altitudinal migrants that feed on bamboo shoots and leaves with different nutritional quality.However,the importance of bamboo shoots to giant pandas,especially small and isolated populations,is not fully appreciated.Here,we explored whether mating time of giant pandas is shaped by bamboo shoot phenology.We also assessed the intensity of ongoing bamboo shoot harvesting by local communities in 42 giant panda reserves based on questionnaire surveys.Varying intensity and protection levels of bamboo shoot harvesting were found.From these data,we developed a priority ranking scheme of protection areas for this key food resource.Our study showed that pandas time their mating behavior to coincide with bamboo shoot phenology due to the high nutritional demands associated with mating and pregnancy.We also found that bamboo shoots were not well protected in many places.Liangshan,Daxiangling,and Xiaoxiangling,containing the most isolated panda populations,were identified as the areas with the most urgent need of protection.Furthermore,equal attention should be paid to the Qiong L-B population,as this region holds considerable potential to serve as a corridor between the Minshan and Qionglai populations.To address the challenges posed by bamboo shoot harvesting,we recommend establishing more practical bamboo shoot management policies,increasing public awareness of bamboo shoot protection,and providing alternative sources of income for local communities.展开更多
Background Forage inclusion in starters of young dairy calves has become an acceptable strategy in the last decade.To compensate for the lower energy provided by forage,concurrent lipid supplementation can be proposed...Background Forage inclusion in starters of young dairy calves has become an acceptable strategy in the last decade.To compensate for the lower energy provided by forage,concurrent lipid supplementation can be proposed.How-ever,ruminal microbial activity and forage digestibility may be decreased by lipid supplementation.We hypothesized that the composite effect of forage and lipid supplements may be dependent on forage particle size and the type of lipid supplement.Therefore,we evaluated the effect of long(LP;geometric mean,4.97 mm)vs.short alfalfa hay particle sizes(SP;geometric mean,1.26 mm)with either soybean oil(SBO)or palm fatty acids(PLF)as lipid source in a 2×2 factorial design with treatments SP-SBO,SP-PLF,LP-SBO,and LP-PLF.Treatments(n=13 with 6 males and 7 females each)were offered to Holstein calves(3 days old)with equal amounts of lipid(25 g/kg DM)through-out the experimental period.The milk offering scheme(d 1 to 53)was equal for all groups.Data collection continued until 20 d post-weaning.Results Interaction between forage particle size and lipid supplement was significant for the following readouts:the highest and lowest starter intakes during the pre-weaning period occurred in LP-PLF and LP-SBO,respectively.This was associated with similarly contrasting changes in average daily gain(ADG)during the post-weaning period,body weight at the end of experiment,withers height,digestibility of organic matter and neutral detergent fiber,and blood serum concentrations of glucose,beta-hydroxybutyrate,and insulin during the pre-weaning period.Dur-ing both pre-and post-weaning periods,the highest and lowest urinary excretion of allantoin and total purine deriva-tives,representing microbial protein synthesis,were observed in LP-PLF and LP-SBO,respectively,indicating that those diets were most and least favorable for rumen development.Irrespective of forage particle size,supplemental SBO vs.PLF increased serum malondialdehyde as an oxidative stress indicator across periods,increased blood urea nitrogen and feed efficiency in the pre-weaning period,and reduced hip height during the post-weaning period.Conclusions It can be concluded that feeding a rumen-inert,mostly saturated fatty acid source with alfalfa hay as long particle size is recommended with view on performance,whereas a combination soybean oil rich in unsatu-rated fatty acids should not be provided to milk-fed Holstein calves together with long particle forage.Feeding soybean oil and alfalfa hay as long particles is not advisable mainly due to lower starter consumption and impaired development of ruminal function.If dietary supplementation of soybean oil is applied,incorporation of forage as small particles should be preferred to support rumen development.展开更多
Niche partitioning is a widespread ecological strategy within trophic guilds,ensuring the coexistence of sympatric species by reducing interspecific competition.Stable isotope analysis of carbon and nitrogen and isoto...Niche partitioning is a widespread ecological strategy within trophic guilds,ensuring the coexistence of sympatric species by reducing interspecific competition.Stable isotope analysis of carbon and nitrogen and isotopic niche metrics(width and overlap)are used as a proxy to investigate niche partitioning among species of a guild.In our study,we investigated if niche partitioning was an ecological mechanism contributing to the coexistence of granivorous birds from the same geographic region along time,employing an isotopic approach.We sampled and isotopically analyzed(δ^(13)C andδ^(15)N values)wing feathers from 58 specimens of granivorous birds collected between 1900 and 1966 in southeastern Brazil.We grouped birds according to the main habitat type used by them(forest:Cyanoloxia brissonii,Leptotila and Leptotila verreauxi;and grassland:Columbina squammata and Sicalis flaveola).We used the Isotopic Richness(IRic)metric to measure the isotopic niche width and the Isotopic Similarity(ISim)and Isotopic Nestedness(INes)metrics to measure the niche overlap between groups and species.The results of low isotopic niche overlap suggest that common granivorous birds had a clear niche partitioning in southeastern Brazil in the late past,especially through foraging in distinct habitat types(forest and grassland;ISim=0.1,INes=0.2).Niche overlaps in almost all species-by-species comparisons were low(ISim≤0.3,INes≤0.4),except between C.brissonii and L.verreauxi(ISim=0.6,INes=1.0).These results suggest that these birds,belonging to the same trophic guild,coexisted through niche and resource partitioning.Despite being considered a plastic trophic guild,the isotopic niche partitioning among granivorous birds indicates that each of these species uses a set of specific resources and habitats.This raises an ecological concern about the homogenization of landscapes across the Neotropics,oversimplifying food resources and habitats to granivorous birds.展开更多
Object detection and classification are the trending research topics in thefield of computer vision because of their applications like visual surveillance.However,the vision-based objects detection and classification met...Object detection and classification are the trending research topics in thefield of computer vision because of their applications like visual surveillance.However,the vision-based objects detection and classification methods still suffer from detecting smaller objects and dense objects in the complex dynamic envir-onment with high accuracy and precision.The present paper proposes a novel enhanced method to detect and classify objects using Hyperbolic Tangent based You Only Look Once V4 with a Modified Manta-Ray Foraging Optimization-based Convolution Neural Network.Initially,in the pre-processing,the video data was converted into image sequences and Polynomial Adaptive Edge was applied to preserve the Algorithm method for image resizing and noise removal.The noiseless resized image sequences contrast was enhanced using Contrast Limited Adaptive Edge Preserving Algorithm.And,with the contrast-enhanced image sequences,the Hyperbolic Tangent based You Only Look Once V4 was trained for object detection.Additionally,to detect smaller objects with high accuracy,Grasp configuration was observed for every detected object.Finally,the Modified Manta-Ray Foraging Optimization-based Convolution Neural Network method was carried out for the detection and the classification of objects.Comparative experiments were conducted on various benchmark datasets and methods that showed improved accurate detection and classification results.展开更多
A study was conducted in Northern Province of Rwanda, from the College of Agriculture and Veterinary Medicine, Busogo Campus located in Musanze district to evaluate the effect of feed type on rabbit growth in rabbit i...A study was conducted in Northern Province of Rwanda, from the College of Agriculture and Veterinary Medicine, Busogo Campus located in Musanze district to evaluate the effect of feed type on rabbit growth in rabbit intensification systems in Rwanda. The Complete Randomized Design (CRD) was used and data were collected on rabbit growth weekly for a period of 12 weeks. The experiment was composed of three treatments replicated ten times. The treatments included three types of feeds namely;cabbage combined with Mucuna pruriens added to local forage (I), cabbages combined with Leucaena leucocephala added to local forage (II) and a control composed of other varieties of locally available forage, such as Bidens pilosa, Crassocephalum vitellium and Galinsoga parviflora (III) which was considered as the control (Farmers practice). The feeds were given to ten rabbits separated in individual cages, and each rabbit was considered a replicate. Water was given ad libitum. One month old rabbits (weaners) were used and data were collected after one week of adaptation for 12 weeks. The results showed that the mean of weight gain after 12 weeks was 783.3 g, 760.7 g and 705.7 g for feed type I, II and III respectively. The difference between means of feed types after 12 weeks was not significant (p > 0.5), which implied that rabbit growth did not depend on the feed type. The mean weight gain after 8 weeks was 707.5 g, 661.4 g and 577.1 g for feed type I, II and III respectively. At 8 weeks, the difference between means of feed types was significant (p Mucuna pruriens combined with cabbage and local forage were growing faster than rabbits from other treatments at 8 weeks. The researchers recommended that farmers should be facilitated with feeding materials by the concerned institutions. Training of rabbit farmers and further researches on locally available feeding materials were also given as recommendations at the end of this study.展开更多
[Objectives] Caragana korshinskii resources are rich in Ordos with a large planting area, but they have not been fully and reasonably utilized. This study aims to effectively convert C. korshinskii into high-quality f...[Objectives] Caragana korshinskii resources are rich in Ordos with a large planting area, but they have not been fully and reasonably utilized. This study aims to effectively convert C. korshinskii into high-quality feed, improve the quality of milk and meat of herbivores and increase production. [Methods] The utilization of C. korshinskii in feed was studied in various aspects, the factors were selected, the level was determined, and the multi-factor experiment—orthogonal experiment was conducted. [Results] The effect on the growth of sheep was in the order of silage > C. korshinskii feed > corn stalk silage > hay meal, and the effect on the growth of goats was in the order of hay meal > C. korshinskii feed > silage > corn stalk silage. [Conclusions] From the analysis of the range results, the best level combination was selected: in different growing seasons, C. korshinskii branch and leaf silage in full-bloom stage had the greatest effect on the growth of sheep and goats, and the fattening effect was the best;among the different silage methods of C. korshinskii, the C. korshinskii—corn stalk mixture silage had a good feeding effect for sheep and goats.展开更多
Natural pastures constitute a major component of ruminant livestock feed, and are the most cost-effective feed resource available for smallholder subsistence farmers. However, this feed resource does not meet animal n...Natural pastures constitute a major component of ruminant livestock feed, and are the most cost-effective feed resource available for smallholder subsistence farmers. However, this feed resource does not meet animal nutritional requirement due to deficiency in nitrogen, energy and minerals. In addition, at maturity lignification is the major concern since it reduces digestibility and contributes to methane emission. Thus, the objective of this study was to evaluate the effect of supplementing low-quality Eragrostis grass hay with five (9281, 11,252, 11,255, 11,595 and 11,604) selected Stylosanthes scabra accessions on in vitro ruminal fermentation and neutral detergent fiber degradation. Therefore, in vitro study was conducted on grass hay, accessions and the mixture of grass hay with each accession included at two (15%, 30%) levels. The substrates (grass hay, accessions and the mixtures) were incubated in separate serum bottles for 72 h. Neutral detergent fiber (NDF) of the accessions ranged from 300 to 350 g/kg DM with crude protein (CP) value ranging from 177.5 to 184.1 g/kg DM. Eragrostis grass hay had NDF value of 813 g/kg DM, with CP value of 34.3 g/kg DM. Grass hay fermented slowly, it took 30 h for grass hay to produce gas volume above 50 mL, while Stylosanthes scabra accessions took 12 h. Supplementing grass hay with accessions significantly improved fermentation. However, it was observed that 15% inclusion took 30 h to produce gas volume above 50 mL, whereas at 30% inclusions it took 24 h for accession 9281, 11,595 and 11,604. Accession 11,604 improve grass fermentation by almost three times the value of grass hay in 2 h. Grass hay supplemented with accession 11,604 at 30% had a positive associative effect and significantly improved NDF degradability. In conclusion, accession 11,604 may be fed strategically as forage supplement to low-quality forage for ruminants.展开更多
文摘Recent advances in our understanding of avian chemical communication have highlighted the importance of olfaction in many aspects of avian life.Prior studies investigating predator avoidance behaviors in response to predator odor cues have produced mixed results across species and contexts.Here we assess if a community of birds in eastern Pennsylvania displays avoidance behaviors towards predator odor cues in a natural foraging setting.We use clay caterpillars to measure foraging activity by birds in the presence of predator(bobcat)urine,non-predator(rabbit)urine,and water controls in two different environmental contexts(field vs.forest).Although we detected a weak trend for birds to forage less at predator urine-treated sites,we found no significant difference in avian foraging between the site types.We did find that foraging rates between environmental contexts changed significantly over the course of the experiment,with forest sites showing decreasing foraging rates and field sites showing increasing foraging rates.Our results reinforce the published literature that avoidance of predator odors by birds may not be ubiquitous across contexts and species.
基金funded by the National Natural Science Foundation of China(Grant No.32360142).
文摘Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi-encing increased aridity.Although numerous studies have investigated birds’responses to drought,the emphasis has primarily been on landbirds.Drought can significantly alter the wetland environments that waterbirds inhabit,but the response of waterbirds to drought remains understudied.In this study,we surveyed the distri-bution and behavior of Oriental Storks(Ciconia boyciana)in Poyang Lake,which is the largest freshwater lake in China.Results indicate that drought-induced catchment areas at the lowest water level limited the total popu-lation size of Oriental Storks in the sub-lakes.Sub-lakes with large catchment areas at the lowest water level demonstrated a capacity to support a larger population of wintering Oriental Storks.Over time,Oriental Storks exhibited a gradual concentration in Changhu Lake,characterized by larger catchments,after resource depletion in sub-lakes with smaller catchments.Additionally,the duration of Oriental Storks’vigilance and moving be-haviors decreased significantly compared with that observed before the drought.After the drought,Oriental Storks increased their foraging efforts,as evidenced by increased presence in deeper water and reaching their heads and necks into deeper water to forage,higher search rates,but lower foraging rates.In accordance with area-restricted search theory,reductions in habitat quality resulting from drought,including extensive fish die-offs,forced Oriental Storks to increase their foraging efforts.Sustaining a specific water area in sub-lakes during droughts can preserve resource availability,which is crucial for the conservation of Oriental Storks.Imple-menting measures such as water level control and micro-modification of lake bottoms in sub-lakes might mitigate the impact of drought on the piscivorous Oriental Storks.
基金Project supported by the National Natural Science Foundation of China(Grant No.31971183).
文摘Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell migration,and cell–cell interactions.One of the fundamental characteristics of cell movement is the specific distribution of cell speed,containing valuable information that still requires comprehensive understanding.This article investigates the distribution of mean velocities along cell trajectories,with a focus on optimizing the efficiency of cell food search in the context of the entire colony.We confirm that the specific velocity distribution in the experiments corresponds to an optimal search efficiency when spatial weighting is considered.The simulation results indicate that the distribution of average velocity does not align with the optimal search efficiency when employing average spatial weighting.However,when considering the distribution of central spatial weighting,the specific velocity distribution in the experiment is shown to correspond to the optimal search efficiency.Our simulations reveal that for any given distribution of average velocity,a specific central spatial weighting can be identified among the possible central spatial weighting that aligns with the optimal search strategy.Additionally,our work presents a method for determining the spatial weights embedded in the velocity distribution of cell movement.Our results have provided new avenues for further investigation of significant topics,such as relationship between cell behavior and environmental conditions throughout their evolutionary history,and how cells achieve collective cooperation through cell-cell communication.
基金supported by the National Natural Science Foundation of China(T2350005 to YL)。
文摘Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to maximize energy gains and cope with the intensified challenges of parenting and self-maintenance.Such tradeoff may stem from the heterogeneity of food resources and the constraints of central place foraging.Nevertheless,abundant marine productivity could alleviate the energy limitation for seabirds,resulting in a consistent foraging approach.Here,we investigated the foraging strategy during the breeding season of a cryptic small-sized seabird,Swinhoe’s Storm-petrel(Hydrobates monorhis),in the Yellow Sea,a productive marginal sea of the Northwest Pacific.Using GPS tracking,we evaluated habitat preference,quantified the foraging strategy,and tested if environmental conditions and individual traits influence foraging trips.We found that Swinhoe’s Storm-petrels preferred nearshore areas with shallow water and engaged in primarily short foraging trips.Distinctive southeastward and southwestward strategies emerged when combining trip metrics,including foraging direction,duration,and maximum distance.The bathymetry,proximity to the coastline,and sea surface temperature differed in two foraging strategies.Foraging strategies exhibited flexibility between individuals,potentially explained by wing morphology,in which longer-winged birds are more likely to embark on longer-distance foraging trips.These findings highlight the impact of environmental factors and individual traits on seabirds’foraging decisions in productive marginal sea ecosystems.Our study also provides valuable insights into the foraging ecology of this Asian endemic storm-petrel.
基金supported by the National Natural Science Foundation of China(52177081).
文摘In order to play a positive role of decentralised wind power on-grid for voltage stability improvement and loss reduction of distribution network,a multi-objective two-stage decentralised wind power planning method is proposed in the paper,which takes into account the network loss correction for the extreme cold region.Firstly,an electro-thermal model is introduced to reflect the effect of temperature on conductor resistance and to correct the results of active network loss calculation;secondly,a two-stage multi-objective two-stage decentralised wind power siting and capacity allocation and reactive voltage optimisation control model is constructed to take account of the network loss correction,and the multi-objective multi-planning model is established in the first stage to consider the whole-life cycle investment cost of WTGs,the system operating cost and the voltage quality of power supply,and the multi-objective planning model is established in the second stage.planning model,and the second stage further develops the reactive voltage control strategy of WTGs on this basis,and obtains the distribution network loss reduction method based on WTG siting and capacity allocation and reactive power control strategy.Finally,the optimal configuration scheme is solved by the manta ray foraging optimisation(MRFO)algorithm,and the loss of each branch line and bus loss of the distribution network before and after the adoption of this loss reduction method is calculated by taking the IEEE33 distribution system as an example,which verifies the practicability and validity of the proposed method,and provides a reference introduction for decision-making for the distributed energy planning of the distribution network.
文摘Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM ha<sup>-1</sup>) and contributed the most total N (167 kg∙ha<sup>-1</sup>) and total C (3043 kg∙ha<sup>-1</sup>) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea produced 8.41 t DM ha<sup>-1</sup> with a total N yield of 319 kg N ha<sup>-1</sup> and total C production of 3835 kg C ha<sup>-1</sup>. The WSL treatments had only small effects on rye forage yield and N concentration, possibly due to mineralization of N from a large SOC pool already in place. The CSL treatments also had only minimal effects on sorghum-sudangrass forage production. Winter pea, arrow leaf and crimson clover were productive cool season legumes and could be useful as green manure crops. Mungbean and cowpea (Vigna unguiculata [L.] Walp.) were highly productive warm season legumes but may include more production risk in green manure systems due to soil moisture competition.
基金supported by the National Natural Science Foundation of China (31821001)Strategic Priority Research Program of the Chinese Academy of Sciences (XDB3100000)。
文摘A critical function of animal movement is to maximize access to essential resources in temporally fluctuating and spatially heterogeneous environments.Seasonally mediated resource fluctuations may influence animal movements,enabling them to track changing resource distributions,resulting in annual migration patterns.The conservation-dependent giant panda(Ailuropoda melanoleuca) displays seasonal movement patterns;however,the key factor driving these seasonal migration patterns remains poorly understood.Here,we used GPS tracking collars to monitor the movements of six giant pandas over a 12-year period across different elevations,and performed statistical analysis of seasonal migration directions,routes,habitat revisitation,home range overlap,first arrival events,and stability.Our results revealed a compelling pattern of seasonal migrations that facilitated the ability of the pandas to forage at the appropriate time and place to maximize nutritional intake.Our results indicated that pandas utilize spatial memory to locate reliable food resources,as evidenced by their annual return to the same or similar winter and summer home ranges and the consistently maintained percentage of home range overlap.These novel insights into giant panda foraging and movement ecology not only enhance our understanding of its ability to adapt to nutritionally poor dietary resources but also provide important information for the development of resource utilization-based protection and management strategies.
基金supported by the National Key Research and Development Program(No.2021YFF1000703,NKPs)funded by the Ministry of Science and Technology of the People’s Republic of China.
文摘Background Previous investigations into the effect of dietary forage on calf performance have been inconsistent,and there is a paucity of information exploring the effect of age on the growth performance and rumination of calves.Eighty-four female Holstein calves(41.5±4.2 kg)were enrolled at birth,a subset of the calves were fed calf starter only(CON,n=21)while the rest(n=63)were classified into three treatment groups:the early(EHAY,n=26,5.1±0.8 d),the middle(MHAY,n=21,7.9±0.8 d)and the late(LHAY,n=16,12.1±1.4 d)hay consumers.The short-term effect of the age at first forage consump-tion(AFF)on calves’feed intake was monitored until d 84.In addition,the long-term effects of AFF on body weight,structural growth and rumination behavior were recorded until d 196.Rumen samples were collected on d 1,7,35,84 and 196 to ana-lyze the rumen fermentation,while fecal samples were collected from d 78 to 84 to estimate digestibility parameters.Results Treatment had no effect on feed intake.While,the EHAY calves tended to have lower BW and ADG compared to LHAY and CON calves.Several total-tract apparent digestibility parameters and digestible nutrients intake were significantly lower in EHAY calves compared with CON and LHAY calves.Calves in the EHAY group tended to begin ruminating ealier,while CON calves were the latest(12.3 vs.15.5 days of age).A treatment and time interaction was present for rumination time due to greater rumination in calves consuming hay compared to CON calves in week 10 to 12,the differences in rumination disappeared afterwards,no long-lasting significant differences in the rumina-tion and rumen fermentation parameters were found between treatments.Conclusions In conclusion,this study showed that hay consumption earlier in life(in the first week,around 5 days of life)could negatively affect the growth of the calf in the short and long term.Compared to consuming hay from the second week(around 12 days of life)or feeding concentrate only without hay,starting to consume hay from the first week could compromise nutrient digestibility and digestible nutrient intake independent of developing rumination behaviour and rumen fermentation.
文摘A significant advantage of medical image processing is that it allows non-invasive exploration of internal anatomy in great detail.It is possible to create and study 3D models of anatomical structures to improve treatment outcomes,develop more effective medical devices,or arrive at a more accurate diagnosis.This paper aims to present a fused evolutionary algorithm that takes advantage of both whale optimization and bacterial foraging optimization to optimize feature extraction.The classification process was conducted with the aid of a convolu-tional neural network(CNN)with dual graphs.Evaluation of the performance of the fused model is carried out with various methods.In the initial input Com-puter Tomography(CT)image,150 images are pre-processed and segmented to identify cancerous and non-cancerous nodules.The geometrical,statistical,struc-tural,and texture features are extracted from the preprocessed segmented image using various methods such as Gray-level co-occurrence matrix(GLCM),Histo-gram-oriented gradient features(HOG),and Gray-level dependence matrix(GLDM).To select the optimal features,a novel fusion approach known as Whale-Bacterial Foraging Optimization is proposed.For the classification of lung cancer,dual graph convolutional neural networks have been employed.A com-parison of classification algorithms and optimization algorithms has been con-ducted.According to the evaluated results,the proposed fused algorithm is successful with an accuracy of 98.72%in predicting lung tumors,and it outper-forms other conventional approaches.
基金supported by the project TOPDEVILfinanced by Fundacão para a Ciencia e a Tecnologia(FCT)and the European Regional Development Fund(FEDER)through Portugal 2020 Competitiveness and Internationalization Operational Programme(POCI),reference POCI-01-0145-FEDER-030250 and PTDC/ASP-SIL/30250/2017funded by FCT through the research contracts 2020.02547.CEECIND and CEECIND/02064/2017,respectively。
文摘Pallid Swifts(Apus pallidus),as other swifts,are birds extremely adapted to an aerial lifestyle,showing unique adaptations that allow them to fly almost continuously.The diet of these non-stopping high-altitudinal aerial birds has been mostly studied through techniques that fail to produce highly resolved prey identifications,and for that have been replaced by molecular techniques,such as DNA metabarcoding.Faecal samples of Pallid Swifts were monthly collected from a colony in the north of Portugal during the breeding season.DNA from the faecal samples was used to sex the birds and to identify the arthropods present in the diet through DNA metabarcoding.From the detected prey items,74 families were identified belonging to 16 orders,with Hymenoptera and Hemiptera being the most frequently consumed.There were seasonal variations in diet richness,composition and prey size.Regarding the diet of males and females,although no differences were found between the diet of males and females in terms of composition and richness,there were differences in the size of arthropods preyed by the different sexes,with males feeding on larger arthropods.The large seasonal variation in Pallid Swifts’diet during the breeding season is probably a result of spatiotemporal variation in aerial prey,of which swifts likely predate opportunistically.Although no significant differences were detected in diet richness and composition between sexes,the fact that males consumed larger prey may suggest the existence of sexual dietary segregation in this group of birds.At last,several pest species were found in these swifts’diet,which,if studied through DNA metabarcoding,can be used to monitor small arthropods,including airborne pests.
基金supported by the Fundamental Research Funds for the Central Universities(BLX202147)the Joint Fund for Regional Innovation and Development of NSFC(U22A20563).
文摘Throughout evolutionary history,animals are finely tuned to adjust their behaviors corresponding to environmental variations.Behavioral flexibility represents an important component of a species'adaptive capacity in the face of rapid anthropogenetic environmental change,and knowledge of animal behaviors is increasingly recognized in conservation biology.In aquatic ecosystem,variation of water depth is a key factor affecting the availability of food;thus,the foraging behaviors of many waterbirds,especially piscivores.In this study,we compared the foraging behaviors of the Scaly-sided Merganser(Mergus squamatus),an endangered migratory diving duck endemic to East Asia,in habitats with different water depths(Shallow waters:0–40 cm;Deep waters:40–300 cm),using video camera records obtained from the known wintering sites during three winters from 2018 to 2020.Further,the energy expenditure of foraging behavior profile and energy intake based on fish sizes were calculated to study the foraging energetics.In total,200 effective video footages that contained 1086 min with 17,995 behaviors and 163 events of catching fish were recorded.Results showed that:1)time length for fishing(including eye-submerging,head-dipping,diving and food handling)of M.squamatus in shallow waters was significantly more than in deep waters;2)M.squamatuss spent significantly more time for preparing(including vigilance,preening and swimming)in deep waters than in shallow waters;3)the mean catch rate was 0.28 fish/min in shallow waters,which is significantly higher than the value of 0.13 fish/min in deep waters;4)despite the distinct foraging behavior profiles and energy intakes,M.squamatus showed similar energetics in shallow and deep waters.We concluded that M.squamatus is a good example of behavioral flexibility that aligns with expectations of optimal foraging theory,in that it behaves in accordance to resource availability in different environments,resulting in high foraging efficiency.
基金supported by the National Natural Science Foundation of China(Nos.61861015,62061013 and 61961013)Key Research and Development Program of Hainan Province(No.ZDYF2019011)+3 种基金National Key Research and Development Program of China(No.2019CXTD400)Young Elite Scientists Sponsorship Program by CAST(No.2018QNRC001)Scientific Research Setup Fund of Hainan University(No.KYQD(ZR)1731)the Natural Science Foundation High-Level Talent Project of Hainan Province(No.622RC619).
文摘At present,the traditional channel estimation algorithms have the disadvantages of over-reliance on initial conditions and high complexity.The bacterial foraging optimization(BFO)-based algorithm has been applied in wireless communication and signal processing because of its simple operation and strong self-organization ability.But the BFO-based algorithm is easy to fall into local optimum.Therefore,this paper proposes the quantum bacterial foraging optimization(QBFO)-binary orthogonal matching pursuit(BOMP)channel estimation algorithm to the problem of local optimization.Firstly,the binary matrix is constructed according to whether atoms are selected or not.And the support set of the sparse signal is recovered according to the BOMP-based algorithm.Then,the QBFO-based algorithm is used to obtain the estimated channel matrix.The optimization function of the least squares method is taken as the fitness function.Based on the communication between the quantum bacteria and the fitness function value,chemotaxis,reproduction and dispersion operations are carried out to update the bacteria position.Simulation results showthat compared with other algorithms,the estimationmechanism based onQBFOBOMP algorithm can effectively improve the channel estimation performance of millimeter wave(mmWave)massive multiple input multiple output(MIMO)systems.Meanwhile,the analysis of the time ratio shows that the quantization of the bacteria does not significantly increase the complexity.
基金supported by the University of Natural Sciences and Humanities in Siedlce and the Institute of Dendrology,Polish Academy of Sciencesupport from the Foundation for Polish Science (FNP) from the START scholarship
文摘Drivers of bird niche separation in temperate primeval forests have not yet been determined,due to the low number of intact forest sites.Here,we analyzed the general patterns of niche usage on trees by birds’assemblages.We tested how tree species affect the sharing of space in an assemblage of birds and their level of specialization.We conducted our study in the Białowieża primeval forest(NE Poland).During two breeding seasons,we observed bird positions on trees,divided into three vertical and six horizontal zones in 768 observation points.Based on the interaction networks framework we calculated the Kullback-Leibler distance d′as a metric of species specialization and the resource range RR index,which estimates the species’specificity based on the fraction of space utilized with a non-zero performance.The d′index was the highest in the lower understory for all parts of the tree on the basis of the position from the trunk.The RR index was the highest in the lower understory for all parts based on the position from the trunk.Regarding the tree species,the lowest d′index was observed in all tree species together,and hornbeam,whereas the highest in oak.At the tree species level,the RR index was the lowest for hornbeam.We show tree species importance in forest space sharing in the case of bird assemblages.Hornbeam,alder,and spruce are universal species that were used by birds almost entirely.In contrast,oak,lime,and maple were only partially used.Tree species with less complex structures could shape bird assemblages,as they could offer birds much fewer niches to realize.Therefore,we showed that high specialization and niche separation are drivers of high bird diversity.Consequently maintaining a diverse stand structure is crucial for biodiversity conservation.
基金supported by the National Natural Science Foundation of China (32071496,32225033)Chinese Academy of Sciences (XDA23080500,QYZDB-SSW-SMC047)。
文摘Animals that live in seasonal environments adjust their reproduction cycle to optimize seasonal forage quality.Giant pandas(Ailuropoda melanoleuca)are seasonal altitudinal migrants that feed on bamboo shoots and leaves with different nutritional quality.However,the importance of bamboo shoots to giant pandas,especially small and isolated populations,is not fully appreciated.Here,we explored whether mating time of giant pandas is shaped by bamboo shoot phenology.We also assessed the intensity of ongoing bamboo shoot harvesting by local communities in 42 giant panda reserves based on questionnaire surveys.Varying intensity and protection levels of bamboo shoot harvesting were found.From these data,we developed a priority ranking scheme of protection areas for this key food resource.Our study showed that pandas time their mating behavior to coincide with bamboo shoot phenology due to the high nutritional demands associated with mating and pregnancy.We also found that bamboo shoots were not well protected in many places.Liangshan,Daxiangling,and Xiaoxiangling,containing the most isolated panda populations,were identified as the areas with the most urgent need of protection.Furthermore,equal attention should be paid to the Qiong L-B population,as this region holds considerable potential to serve as a corridor between the Minshan and Qionglai populations.To address the challenges posed by bamboo shoot harvesting,we recommend establishing more practical bamboo shoot management policies,increasing public awareness of bamboo shoot protection,and providing alternative sources of income for local communities.
基金Open Access funding enabled and organized by Projekt DEALthe first author thesis (Grant No. 95–6102) that was financially supported by University of Zanjan,Iran+1 种基金the Ministry of Science,Research and Technology,Iransupport by the open access publication fund of the Freie Universitat Berlin (Germany)
文摘Background Forage inclusion in starters of young dairy calves has become an acceptable strategy in the last decade.To compensate for the lower energy provided by forage,concurrent lipid supplementation can be proposed.How-ever,ruminal microbial activity and forage digestibility may be decreased by lipid supplementation.We hypothesized that the composite effect of forage and lipid supplements may be dependent on forage particle size and the type of lipid supplement.Therefore,we evaluated the effect of long(LP;geometric mean,4.97 mm)vs.short alfalfa hay particle sizes(SP;geometric mean,1.26 mm)with either soybean oil(SBO)or palm fatty acids(PLF)as lipid source in a 2×2 factorial design with treatments SP-SBO,SP-PLF,LP-SBO,and LP-PLF.Treatments(n=13 with 6 males and 7 females each)were offered to Holstein calves(3 days old)with equal amounts of lipid(25 g/kg DM)through-out the experimental period.The milk offering scheme(d 1 to 53)was equal for all groups.Data collection continued until 20 d post-weaning.Results Interaction between forage particle size and lipid supplement was significant for the following readouts:the highest and lowest starter intakes during the pre-weaning period occurred in LP-PLF and LP-SBO,respectively.This was associated with similarly contrasting changes in average daily gain(ADG)during the post-weaning period,body weight at the end of experiment,withers height,digestibility of organic matter and neutral detergent fiber,and blood serum concentrations of glucose,beta-hydroxybutyrate,and insulin during the pre-weaning period.Dur-ing both pre-and post-weaning periods,the highest and lowest urinary excretion of allantoin and total purine deriva-tives,representing microbial protein synthesis,were observed in LP-PLF and LP-SBO,respectively,indicating that those diets were most and least favorable for rumen development.Irrespective of forage particle size,supplemental SBO vs.PLF increased serum malondialdehyde as an oxidative stress indicator across periods,increased blood urea nitrogen and feed efficiency in the pre-weaning period,and reduced hip height during the post-weaning period.Conclusions It can be concluded that feeding a rumen-inert,mostly saturated fatty acid source with alfalfa hay as long particle size is recommended with view on performance,whereas a combination soybean oil rich in unsatu-rated fatty acids should not be provided to milk-fed Holstein calves together with long particle forage.Feeding soybean oil and alfalfa hay as long particles is not advisable mainly due to lower starter consumption and impaired development of ruminal function.If dietary supplementation of soybean oil is applied,incorporation of forage as small particles should be preferred to support rumen development.
基金supported by the Sāo Paulo Research Foundation(FAPESP)postdoctoral fellowship grants 2018-05970-1 and 2019-11901-5。
文摘Niche partitioning is a widespread ecological strategy within trophic guilds,ensuring the coexistence of sympatric species by reducing interspecific competition.Stable isotope analysis of carbon and nitrogen and isotopic niche metrics(width and overlap)are used as a proxy to investigate niche partitioning among species of a guild.In our study,we investigated if niche partitioning was an ecological mechanism contributing to the coexistence of granivorous birds from the same geographic region along time,employing an isotopic approach.We sampled and isotopically analyzed(δ^(13)C andδ^(15)N values)wing feathers from 58 specimens of granivorous birds collected between 1900 and 1966 in southeastern Brazil.We grouped birds according to the main habitat type used by them(forest:Cyanoloxia brissonii,Leptotila and Leptotila verreauxi;and grassland:Columbina squammata and Sicalis flaveola).We used the Isotopic Richness(IRic)metric to measure the isotopic niche width and the Isotopic Similarity(ISim)and Isotopic Nestedness(INes)metrics to measure the niche overlap between groups and species.The results of low isotopic niche overlap suggest that common granivorous birds had a clear niche partitioning in southeastern Brazil in the late past,especially through foraging in distinct habitat types(forest and grassland;ISim=0.1,INes=0.2).Niche overlaps in almost all species-by-species comparisons were low(ISim≤0.3,INes≤0.4),except between C.brissonii and L.verreauxi(ISim=0.6,INes=1.0).These results suggest that these birds,belonging to the same trophic guild,coexisted through niche and resource partitioning.Despite being considered a plastic trophic guild,the isotopic niche partitioning among granivorous birds indicates that each of these species uses a set of specific resources and habitats.This raises an ecological concern about the homogenization of landscapes across the Neotropics,oversimplifying food resources and habitats to granivorous birds.
文摘Object detection and classification are the trending research topics in thefield of computer vision because of their applications like visual surveillance.However,the vision-based objects detection and classification methods still suffer from detecting smaller objects and dense objects in the complex dynamic envir-onment with high accuracy and precision.The present paper proposes a novel enhanced method to detect and classify objects using Hyperbolic Tangent based You Only Look Once V4 with a Modified Manta-Ray Foraging Optimization-based Convolution Neural Network.Initially,in the pre-processing,the video data was converted into image sequences and Polynomial Adaptive Edge was applied to preserve the Algorithm method for image resizing and noise removal.The noiseless resized image sequences contrast was enhanced using Contrast Limited Adaptive Edge Preserving Algorithm.And,with the contrast-enhanced image sequences,the Hyperbolic Tangent based You Only Look Once V4 was trained for object detection.Additionally,to detect smaller objects with high accuracy,Grasp configuration was observed for every detected object.Finally,the Modified Manta-Ray Foraging Optimization-based Convolution Neural Network method was carried out for the detection and the classification of objects.Comparative experiments were conducted on various benchmark datasets and methods that showed improved accurate detection and classification results.
文摘A study was conducted in Northern Province of Rwanda, from the College of Agriculture and Veterinary Medicine, Busogo Campus located in Musanze district to evaluate the effect of feed type on rabbit growth in rabbit intensification systems in Rwanda. The Complete Randomized Design (CRD) was used and data were collected on rabbit growth weekly for a period of 12 weeks. The experiment was composed of three treatments replicated ten times. The treatments included three types of feeds namely;cabbage combined with Mucuna pruriens added to local forage (I), cabbages combined with Leucaena leucocephala added to local forage (II) and a control composed of other varieties of locally available forage, such as Bidens pilosa, Crassocephalum vitellium and Galinsoga parviflora (III) which was considered as the control (Farmers practice). The feeds were given to ten rabbits separated in individual cages, and each rabbit was considered a replicate. Water was given ad libitum. One month old rabbits (weaners) were used and data were collected after one week of adaptation for 12 weeks. The results showed that the mean of weight gain after 12 weeks was 783.3 g, 760.7 g and 705.7 g for feed type I, II and III respectively. The difference between means of feed types after 12 weeks was not significant (p > 0.5), which implied that rabbit growth did not depend on the feed type. The mean weight gain after 8 weeks was 707.5 g, 661.4 g and 577.1 g for feed type I, II and III respectively. At 8 weeks, the difference between means of feed types was significant (p Mucuna pruriens combined with cabbage and local forage were growing faster than rabbits from other treatments at 8 weeks. The researchers recommended that farmers should be facilitated with feeding materials by the concerned institutions. Training of rabbit farmers and further researches on locally available feeding materials were also given as recommendations at the end of this study.
基金Supported by Demonstration Project of Forestry and Grassland Science and Technology Popularization by Central Finance[NeiLinCaoKeTui(2021)]Major Project of"Revitalizing Mongolia through Science and Technology"(KJXM-EEDS-2020006)Major Science and Technology Project of Inner Mongolia Autonomous Region(2019ZD007)。
文摘[Objectives] Caragana korshinskii resources are rich in Ordos with a large planting area, but they have not been fully and reasonably utilized. This study aims to effectively convert C. korshinskii into high-quality feed, improve the quality of milk and meat of herbivores and increase production. [Methods] The utilization of C. korshinskii in feed was studied in various aspects, the factors were selected, the level was determined, and the multi-factor experiment—orthogonal experiment was conducted. [Results] The effect on the growth of sheep was in the order of silage > C. korshinskii feed > corn stalk silage > hay meal, and the effect on the growth of goats was in the order of hay meal > C. korshinskii feed > silage > corn stalk silage. [Conclusions] From the analysis of the range results, the best level combination was selected: in different growing seasons, C. korshinskii branch and leaf silage in full-bloom stage had the greatest effect on the growth of sheep and goats, and the fattening effect was the best;among the different silage methods of C. korshinskii, the C. korshinskii—corn stalk mixture silage had a good feeding effect for sheep and goats.
文摘Natural pastures constitute a major component of ruminant livestock feed, and are the most cost-effective feed resource available for smallholder subsistence farmers. However, this feed resource does not meet animal nutritional requirement due to deficiency in nitrogen, energy and minerals. In addition, at maturity lignification is the major concern since it reduces digestibility and contributes to methane emission. Thus, the objective of this study was to evaluate the effect of supplementing low-quality Eragrostis grass hay with five (9281, 11,252, 11,255, 11,595 and 11,604) selected Stylosanthes scabra accessions on in vitro ruminal fermentation and neutral detergent fiber degradation. Therefore, in vitro study was conducted on grass hay, accessions and the mixture of grass hay with each accession included at two (15%, 30%) levels. The substrates (grass hay, accessions and the mixtures) were incubated in separate serum bottles for 72 h. Neutral detergent fiber (NDF) of the accessions ranged from 300 to 350 g/kg DM with crude protein (CP) value ranging from 177.5 to 184.1 g/kg DM. Eragrostis grass hay had NDF value of 813 g/kg DM, with CP value of 34.3 g/kg DM. Grass hay fermented slowly, it took 30 h for grass hay to produce gas volume above 50 mL, while Stylosanthes scabra accessions took 12 h. Supplementing grass hay with accessions significantly improved fermentation. However, it was observed that 15% inclusion took 30 h to produce gas volume above 50 mL, whereas at 30% inclusions it took 24 h for accession 9281, 11,595 and 11,604. Accession 11,604 improve grass fermentation by almost three times the value of grass hay in 2 h. Grass hay supplemented with accession 11,604 at 30% had a positive associative effect and significantly improved NDF degradability. In conclusion, accession 11,604 may be fed strategically as forage supplement to low-quality forage for ruminants.