Black soldier fly larvae(Hermetia illucens)receive growing interest as a potential alternative animal feed source.These insects may be exposed to insecticide residues in the rearing substrate.This study aimed to inves...Black soldier fly larvae(Hermetia illucens)receive growing interest as a potential alternative animal feed source.These insects may be exposed to insecticide residues in the rearing substrate.This study aimed to investigate the effects of six different pyrethroid and organophosphate insecticides on this insect species'performance.The toxicity of two"model"substances for each of these classes(cypermethrin;pirimiphosmethyl)was quantified,with and without the synergist piperonyl butoxide(PBO).Critical effect doses corresponding to 10%yield(CED10)for cypermethrin(0.4 mg/kg)and pirimiphos-methyl(4.8 mg/kg)were determined.The addition of PBO to cypermethrin enhanced its relative potency with a factor 2.6.These data were compared against the relative toxicity of two analogue substances in each class(permethrin,deltamethrin;chlorpyrifosmethyl,malathion).Results suggest that exposure to concentrations complying with legal limits can cause significant reductions in yield.Exposure to multiple substances at lower concentrations resulted in negative additive and synergistic effects.Of the tested substances,deltamethrin was most toxic,causing 94%yield at 0.5 mg/kg.Analytical results suggested that transfer of tested substances to the larval biomass was substance-and concentration-specific,but appeared to be correlated to reduced yields and the presence of PBO.Transfer of organophosphates was overall low(<2%),but ranged from 8%to 75%for pyrethroids.Due to very low limits in insect biomass(~0.01 mg/kg),high transfer may result in noncompliance.It is recommended that rearing companies implement lower contractual thresholds,and that policymakers consider adjusting legally allowed maximum residue levels in insect feed.展开更多
A typical Whipple shield consists of double-layered plates with a certain gap.The space debris impacts the outer plate and is broken into a debris cloud(shattered,molten,vaporized)with dispersed energy and momentum,wh...A typical Whipple shield consists of double-layered plates with a certain gap.The space debris impacts the outer plate and is broken into a debris cloud(shattered,molten,vaporized)with dispersed energy and momentum,which reduces the risk of penetrating the bulkhead.In the realm of hypervelocity impact,strain rate(>10^(5)s^(-1))effects are negligible,and fluid dynamics is employed to describe the impact process.Efficient numerical tools for precisely predicting the damage degree can greatly accelerate the design and optimization of advanced protective structures.Current hypervelocity impact research primarily focuses on the interaction between projectile and front plate and the movement of debris cloud.However,the damage mechanism of debris cloud impacts on rear plates-the critical threat component-remains underexplored owing to complex multi-physics processes and prohibitive computational costs.Existing approaches,ranging from semi-empirical equations to a machine learningbased ballistic limit prediction method,are constrained to binary penetration classification.Alternatively,the uneven data from experiments and simulations caused these methods to be ineffective when the projectile has irregular shapes and complicate flight attitude.Therefore,it is urgent to develop a new damage prediction method for predicting the rear plate damage,which can help to gain a deeper understanding of the damage mechanism.In this study,a machine learning(ML)method is developed to predict the damage distribution in the rear plate.Based on the unit velocity space,the discretized information of debris cloud and rear plate damage from rare simulation cases is used as input data for training the ML models,while the generalization ability for damage distribution prediction is tested by other simulation cases with different attack angles.The results demonstrate that the training and prediction accuracies using the Random Forest(RF)algorithm significantly surpass those using Artificial Neural Networks(ANNs)and Support Vector Machine(SVM).The RF-based model effectively identifies damage features in sparsely distributed debris cloud and cumulative effect.This study establishes an expandable new dataset that accommodates additional parameters to improve the prediction accuracy.Results demonstrate the model's ability to overcome data imbalance limitations through debris cloud features,enabling rapid and accurate rear plate damage prediction across wider scenarios with minimal data requirements.展开更多
BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current statu...BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current status of family rearing,parental stress,and behavioral and emotional problems of preschool children and to analyze the mediating effect of the current status of family rearing on parental stress and behavioral/emo-tional problems.METHODS We use convenience sampling to select 258 preschool children in the physical examination center of our hospital from October 2021 to September 2023.The children and their parents were evaluated using a questionnaire survey.Pearson's correlation was used to analyze the correlation between child behavioral and emotional problems and parental stress and family rearing,and the structural equation model was constructed to test the mediating effect.RESULTS The score for behavioral/emotional problems of 258 preschool children was(27.54±3.63),the score for parental stress was(87.64±11.34),and the score for parental family rearing was(31.54±5.24).There was a positive correlation between the behavioral and emotional problems of the children and the“hostile/mandatory”parenting style;meanwhile,showed a negative correlation with the“support/participation”parenting style(all P<0.05).The intermediary effect value between the family upbringing of parents in parental stress and children's behavior problems was 29.89%.CONCLUSION Parental family upbringing has a mediating effect between parental stress and behavioral and emotional problems of children.Despite paying attention to the behavioral and emotional problems of preschool-age children,clinical medical staff should provide correct and reasonable parenting advice to their parents to promote the mental health of preschool-age children.展开更多
Citrus is the highest-yielding fruit crop globally,with China ranking first in both cultivation area and production worldwide.During citrus growth,the crop is often damaged by various pests such as Diaphorina citri,sc...Citrus is the highest-yielding fruit crop globally,with China ranking first in both cultivation area and production worldwide.During citrus growth,the crop is often damaged by various pests such as Diaphorina citri,scale insects,and aphids.Among these,D.citri,the vector of Huanglongbing(citrus greening disease),is particularly severe and has caused substantial economic losses globally.Currently,chemical pesticides remain the primary method for controlling citrus pests.However,their overuse can lead to pest resistance and excessive pesticide residues,posing threats to human health and the environment.Therefore,utilizing natural enemy insects for biological control is of significant importance.This paper systematically reviewed the research progress in artificial rearing of natural enemy insects for citrus pests,aiming to provide references for green pest management in citrus cultivation and promote the healthy and sustainable development of the citrus industry.展开更多
Insects have become an efficient and eco-friendly bioreactor for plastics and even micro/nano-plastics biodegradation.However,the optimal conditions for rearing insects to maximize plastic biodegradation and the under...Insects have become an efficient and eco-friendly bioreactor for plastics and even micro/nano-plastics biodegradation.However,the optimal conditions for rearing insects to maximize plastic biodegradation and the underlying mechanisms remain unclear,hindering its practical applications.We investigated the effects of multiple rearing factors on plastics degradation efficiency of Tenebrio molitor larvae,including larval instar,water addition frequency,plastic specific surface area and plastic types.The functional gut microbes and enzymes associated with the improved efficiency were further explored.Our findings revealed that adult larvae achieved the highest plastics degradation efficiency when receiving regular water additions without causing drowning of insects on hydrophobic plastics.Additionally,they effectively ingested foam plastics of polystyrene,polyethylene and polyurethane without prior comminution and densification.The biodegradation processes involving oxidation,cleavage and depolymerization of plastics were all demonstrated.Furthermore,foam plastic type-dependent functional microbes and enzymes that contributed to the efficient plastic degradationwere identified.Thiswork provides valuable insights into the practical applications of insects for sustainable plastics biodegradation.展开更多
Chouioia cunea Yang is a natural enemy for many kinds of crop and forest pests, particularly for Hyphantria cunea Drary, which is an international quarantine pest. The experiment of rearing Chouioia cunea with Tussah ...Chouioia cunea Yang is a natural enemy for many kinds of crop and forest pests, particularly for Hyphantria cunea Drary, which is an international quarantine pest. The experiment of rearing Chouioia cunea with Tussah (Silkworm) pupa were carried out by 搕hree-cut method?and inoculating method. The results showed that three-cut method is effective way for breed-ing Chouioia cunea, with a parasitical rate of 95%. The biological characteristics and the life cycle of Chouioia cunea were ob-served and described and more hosts of Chouioia cunea were found. 揟hree-cut method?as a new technique of rearing Chouioia cunea has been put into practice.展开更多
[ Objective] The aim of this experiment was to explore the effects of different rearing modes on muscle histological traits and muscle ten demess and to provide theoretical basis for regulating chicken meat quality. [...[ Objective] The aim of this experiment was to explore the effects of different rearing modes on muscle histological traits and muscle ten demess and to provide theoretical basis for regulating chicken meat quality. [ Method] The effects of outdoor rearing, indoor rearing and cage rea ring modes on the muscular histological traits and meat tenderness of Hetian chicken at the age of 8 weeks, 12 weeks and 16 weeks were re searched. [Result] The results showed that the breast and thigh muscle fibre diameter and muscle shear force of outdoor rearing chicken were sig nificently higher than that of cage rearing chicken ( P 〈 0.05), and muscle fibre density was significantly lower than that of cage rearing chicken ( P 〈 0.05). With aging, the muscle fibre diameter and shear force increased and muscle fibre density decreased ( P 〈 0.05). The muscle fibre di ameter and shear force of male were higher than that of female. The correlation analysis showed that the breast muscle shear force had a signifi cantly positive relation with fibre diameter and negative relation with fibre density ( P 〈 0.05), but thigh muscle shear force had an insignificantly pos itive relation with fibre diameter and fibre density. [ Condusion] Muscular histological traits varied in different rearing modes, and the outdoor rearing promoted the muscular fibre development and increased the muscular shear force.展开更多
The White-eared Night Heron (Gorsachius magnificus) is a Class II protected species in China. It is difficult to observe in the field and its population is small. The present study reports a new distribution site in N...The White-eared Night Heron (Gorsachius magnificus) is a Class II protected species in China. It is difficult to observe in the field and its population is small. The present study reports a new distribution site in Nanxiong County, in northern Guangdong Province, where observations of an active nest were made from 4 May to 14 July 2012, the first time consecutive observations have been made for a period of more than two months. The adults flew away from the nest at night, with a peak at 19:00-20:00 and returned in the mornings with a peak at 04:30-05:30. The peak time for feeding young was at 05:00-05:30, accounting for 26.5%of total feeding activities. No feeding occurred from 10:00 to 16:00. The results of our study of its behavior explain why the White-eared Night Heron is usually observed in the evening just before dark, or in the morning before sunrise, at least during the breeding season. There were about 67 days from hatching to fledging, longer than the fledging time of most heron species. This study is the first to cover the entire period of parental care and fills a gap in previous knowledge.展开更多
[ Objective] The aim was to supply technical basis for developing quarantine and control techniques for orient fruit fly. [ Method] By utilizing facilities including rearing chamber and rearing cage, the population of...[ Objective] The aim was to supply technical basis for developing quarantine and control techniques for orient fruit fly. [ Method] By utilizing facilities including rearing chamber and rearing cage, the population of orient fruit fly was established and sustained by using the methods of artificial feeding and fruit culture, and the continuous indoor biological observation was carried out. The isolated enclosure equipped with temperature and humidity recorder was established in Dongshan area of Taihu for cultivating various species of host plants, then the living habits of orient fruit fly were observed everyday. [ Result] Through feeding and observation in lab, the living habit of adult, larva, pupa and eggs of orient fruit fly were studied; the impact of soil depth on the emergence rate of pupa were conducted, and the result indicated that when the soil layer depth increased to 40 cm, there were still adults appeared and their emergence rate was 80%. The results of indoor trend test showed that the selectivity of orient fruit fly on fruits produced in Suzhou was sequenced from high to low as follows: tangerine, dates, pomegranate, peach, orange, pear and persimmon. While the sequence of fruit tree species were tangerine, dates, pomegranate, pears and persimmons according to damage rates of orient fruit fly from high to low under field isolation rearing conditions. In the local tangerine varieties, the damage rate from high to low were Dongting manda- rin, eady tangerine, Wen orange, Huangpi, Zaohong, Liaohong. [ Conclusion] Orient fruit fly artificial rearing facility was established, which laid the foundation for carrvina out bioloaical characteristics observation and biolooical exoeriments展开更多
[Objective] The aim was to seek the optimal choice of hormones,induced temperature,and initial feed for cultivating loach.[Method] Different hormones were injected to Ioaches for artificial reproduction in water at di...[Objective] The aim was to seek the optimal choice of hormones,induced temperature,and initial feed for cultivating loach.[Method] Different hormones were injected to Ioaches for artificial reproduction in water at different temperatures.During cultivation,varied initial feeds were put in to explore the optimal choice of hormones,temperature and initial feed.[Result] According to the test,fecundity of female loach is directly proportional to gonad maturity,namely,the higher gonad maturity,the more fecundity.For example,for a female loach whose maturity coefficient was 24%,absolute and relative fecundity rates were 62 142 and 990.In contrast,for a female whose maturity coefficient was 9%,the rates were 18 207 and 367,respectively.The induced effect differs upon hormones and the test demonstrated that LRH-A2 is better in improving fertility rate compared with HCG.For example,the fertility rate in the group with HCG was 78.84 and in the group with LRH-A2 was 83.04%.It is notable that the mixture of the two at a certain ratio would enhance induced effect and the fertility rate can be as high as 89.17%.With temperature in a certain range,the higher temperature,the better induced effect.The test indicated that water temperature at (30±0.5) ℃ is an optimal one and the effect horizon is 6-8 h.In group 4,induced rate was 93.33% and the fertility rate was 89.26%.The research indicated that the survival rate was the highest if wheel animalcule,dominated by Brachionus calyciflorus and Brachionus angularis,was taken as an initial feed,followed by artemia nauplii and corpuscule.In addition,loach fry in the group with yolk and wheel animalcule grew about 1.21 times than the group with only yolk,1.04 times than the group with only fairy shrimp,and 1.1 times than the group with fairy shrimp.[Conclusion] The research provides scientific references for scale loach farming.展开更多
[Objective] The research aimed to optimize laboratory artificial rearing methods for Plutella xylostella L. and to select out effective insecticides against this pest species. [Method] Brassica chinensis seedlings wer...[Objective] The research aimed to optimize laboratory artificial rearing methods for Plutella xylostella L. and to select out effective insecticides against this pest species. [Method] Brassica chinensis seedlings were cultivated in the laboratory at (25±1)℃, 60-75% RH, and a photoperiod of 14:10 (L:D) h. The green blow molding papers were used to collect eggs, and Brassica oleracea seedlings were cultivated to breed Plutella xylostella L. until the insects were ready for use. Mean-while, the susceptibility of 3rd instar larvae of Plutella xylostella L. to five types of insecticides was tested by leaf-dipping method. [Result] Plutella xylostella L. larvae were found well-grown and uniform in developmental stages with average pupa weight of 5.4 mg, pupa emergence percentage of 94.0 % and egg number of 135.1 per female. The LCso values of 3rd instar Plutella xylostella L. larvae against 200 g/L chlorantraniliprole SC, 20% flubendiamide WG, 150 g/L indoxacarb EC, 200 g/L tebufenozide SC and 1.8% abamectin EC, were 0.152, 0.223, 1.151, 93.340 and 0.128 mg/L, respectively. [Conclusion] This rearing method is easy to be implemented and of great practicality, suitable for mass propagation of P. xylostella L. Abamectin, chlorantraniliprole and flubendiamide showed high insecticidal activities, so these three insecticides can be used alternately for the field prevention and control of Plutella xylostella L.展开更多
In the White sturgeon fish farms, some individuals have difficulty in getting access to food: such sturgeons are called "runts", and they result in a slower growth rate than normally feeding fish. In this pa...In the White sturgeon fish farms, some individuals have difficulty in getting access to food: such sturgeons are called "runts", and they result in a slower growth rate than normally feeding fish. In this paper, we have studied the gut peculiarities of runt sturgeons. Utilizing in paralleling an analysis of diatom populations in both the fish gut tissues and the rearing tank waters, we hypothesized a causative relation between the occurrence of runt sturgeons and periodic diatom blooms. In fact, we have observed that the diatom species identified in the aquatic environment were also detected in organs (Fragilaria spp and Rhoicosfenia spp for both glandular body, mid-intestine) of the runt sturgeon's gut, but not in tissues of normally feeding individuals. Owing to their siliceous wall, diatoms can be responsible for areas of epithetlial detachment in the mucosal surfaces of the alimentary canal and a catharral inflammation in both the gastric pits and intestinal folds which may be the cause of secondary bacterial diseases. We suggest that diatom blooms may contribute to the occurrence of runt sturgeons in the studied Italian fish farm.展开更多
Calves are the reserve forces for dairy cattle. Scientific rearing strategy of calves is the basis of efficient cattle breeding. However, many problems exist in current rearing systems of calves and restrict the susta...Calves are the reserve forces for dairy cattle. Scientific rearing strategy of calves is the basis of efficient cattle breeding. However, many problems exist in current rearing systems of calves and restrict the sustainable development of dairy cattle in China. The absence of basic research is the most highlighted problem among them. Recent researches on growth performance, nutrient digestibility, blood biochemical indices and rumen development in calves were summarized in this paper. Additionally, the optimal levels of energy and protein in milk replacer and starter diets for calves were indicated, and limiting amino acids for calves fed different diets were discussed. A variety of additives, such as acidifiers, probiotics and polysaccharides, are regarded as promising alternatives to antibiotics to reduce disease in calves. Dietary supplementations of these additives have positive effects on growth and health of calves. However, studies on the nutrition of vitamins and minerals in calves have been seldom done, and deserve our further researches. To sum up, the postnatal period is one of the most critical “windows” for rumen manipulation and epigenetic regulation. Any changes from environments, especially early nutrition, may produce long-term effects on growth, health and milk yields in adult cattle.展开更多
Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data...Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data of Taibus Banner, Duolun county and Zhengxiangbai Banner in the Inner Mongolia autonomous region of China, we identified the impact of livelihood diversification on ecosystems in these agro-pastoral areas by using the ecological footprint theory and methodology together with the one-way analysis of variance (ANOVA) and correlation analysis methods. In 2011, the total ecological footprint of consumption (EFC) was 0.665 g hm2, and the total ecological footprint of production (EFP) was 2.045 g hm2, which was more than three times the EFC. The ecological footprint of arable land consumption (EFAC) accounted for a large proportion of the EFC, and the ecological footprint of grassland production (EFGP) occupied a large proportion of the EFP. Both the ecological footprint of grassland consumption (EFGC) and EFGP had a significant positive correlation with the income, indicating that income was mainly depended on livestock production and the households with higher incomes consumed more livestock prod- ucts. The full-time farming households (FTFHs) had the highest EFP, ecological footprint of arable land production (EFAP), EFGP and EFGC, followed by the part-time farming households (PTFHs) and non-farming households (NFHs), which indicated that part-time farming and non-farming employment reduced the occupancy and con- sumption of rural households on local ecosystems and natural resources to some extent. When farming households engaged in livestock rearing, both the EFAP and EFAC became smaller, while the EFP, EFC, EFGC and EFGP increased significantly. The differences in ecological footprints among different household groups should be taken into account when making ecosystem conservation policies. Encouraging the laborers who have the advantages of participating in non-farming employment to move out of the rural areas and increasing the diversification of liveli- hoods of rural households are important in reducing the environmental pressures and improving the welfare of households in the study area. Moreover, grassland should be utilized more effectively in the future.展开更多
Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural proper...Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural properties and filed application of backfill hydraulic support,this work has firstly proposed the basic principle of backfill hydraulic support optimization design and provided the method of optimal design of key structural components,like four-bar linkage,rear canopy and tamping structure;the method is further elaborated as changing hinging position of upper bar to optimize four-bar linkage,by lengthening or shortening the rear canopy to optimize length ratio of canopy;and by changing length and hinging position of tamping structure as well as suspension height of backfill scrape conveyor to realize optimization of tamping structure.On this basis,the process of optimal design of backfill hydraulic support is built.The optimal design case of ZC5200/14.5/30 six columns-four bar linkage used in 7203 W workface of Zhaizhen Coal Mine shows that the backfill properties like horizontal roof gap,vertical horizontal gap,tamping angle and tamping head gap are improved obviously through optimizing four-bar linkage,canopy length and tamping structure according to the optimal design method proposed in this work.展开更多
Experiments were conducted to study the effects of dietary taurine and housing density on oviduct function in laying hens. Green-shell laying hens were randomly assigned to a free range group and two caged groups, one...Experiments were conducted to study the effects of dietary taurine and housing density on oviduct function in laying hens. Green-shell laying hens were randomly assigned to a free range group and two caged groups, one with low-density and the other with high-density housing. Each group was further divided into control(C) and taurine treatment(T) groups. All hens were fed the same basic diet except that the T groups' diet was supplemented with 0.1% taurine. The experiment lasted 15 d. Survival rates, laying rates, daily feed consumption, and daily weight gain were recorded. Histological changes, inflammatory mediator levels, and oxidation and anti-oxidation levels were determined. The results show that dietary taurine supplementation and reduced housing density significantly attenuated pathophysiological changes in the oviduct. Nuclear factor-κB(NF-κB) DNA binding activity increased significantly in the high-density housing group compared with the two other housing groups and was reduced by taurine supplementation. Tumor necrosis factor-α(TNF-α) m RNA expression in the high-density and low-density C and T groups increased significantly. In the free range and low-density groups, dietary taurine significantly reduced the expression of TNF-α m RNA. Supplementation with taurine decreased interferon-γ(IFN-γ) m RNA expression significantly in the low-density groups. Interleukin 4(IL-4) m RNA expression was significantly higher in caged hens. IL-10 m RNA expression was higher in the high-density C group than in the free range and low-density C groups. Supplementation with taurine decreased IL-10 m RNA expression significantly in the high-density group and increased superoxide dismutase(SOD) activity in the free range hens. We conclude that taurine has important protective effects against oviduct damage. Reducing housing density also results in less oxidative stress, less inflammatory cell infiltration, and lower levels of inflammatory mediators in the oviduct. Therefore, both dietary taurine and reduced housing density can ameliorate oviduct injury, enhance oviduct health, and promote egg production in laying hens.展开更多
In this study,firstly,for the axisymmetric RVABI,the change-rule of adverse pressure gradient caused by radial velocity during the transition of internal flow mode in variable geometry is summarized,and a Bypass Ratio...In this study,firstly,for the axisymmetric RVABI,the change-rule of adverse pressure gradient caused by radial velocity during the transition of internal flow mode in variable geometry is summarized,and a Bypass Ratio(BR) iterative algorithm based on the empirical correlation of non-equilibrium pressure is proposed.The algorithm can estimate the nonlinear relationship between area ratio and BR,with an error range falling below 6.5%.Then,we discuss the favorable effect of uniform mixing on the thrust augmentation of mixed exhaust under variable BR conditions.From this point of view,the characteristics of vortices evolution in different shear strength jets are compared,to clarify the effect of variable cycle parameters on jet mixing.As the results suggest,when ■ is as low as 0.22,the K-H disturbance is of high-frequency wavelet property,and it is difficult to induce large-scale spanwise vortices.The macro migrations of fluid elements in span wise vortices and the diffusion effect caused by edge tearing is weak,which is not conducive to the energy exchange between the two streams.However,the low ■ jet will also correspondingly weaken the viscous dissipation effect of vortices.It is concluded that the dissipation level is proportional to the 2.31 power of the ■.展开更多
Objective:Empathy can help establish harmonious nurse-patient relationships.We aimed to assess the status of empathy,and explore the relationship between learning burnout,parental rearing patterns and empathy amongst ...Objective:Empathy can help establish harmonious nurse-patient relationships.We aimed to assess the status of empathy,and explore the relationship between learning burnout,parental rearing patterns and empathy amongst nursing students.Method:A questionnaire survey that employed the Learning Burnout Scale,the Short-Form Egna Minnenav Barndoms Uppfostran(s-EMBU)and the Jefferson Scale of Empathy was conducted amongst 562 nursing students.The data were analysed on the basis of descriptive statistic and correlation analysis was used.Results:Empathy is negatively correlated with learning burnout,parental rejection and overprotection and showed no positive correlation with parental emotional warmth.Conclusions:Educators should pay attention to nursing students'feelings and learning burnout status and take positive measures to improve the empathy level of the students.Positive parental rearing patterns also help cultivate empathy.展开更多
基金funded by the Netherlands Ministry of Economic Affairs(further:The Ministry)through a Public-Private Partnership project("Controlling the safety of insects for food and feed")of the Topsector AgriFood(LWV19099).
文摘Black soldier fly larvae(Hermetia illucens)receive growing interest as a potential alternative animal feed source.These insects may be exposed to insecticide residues in the rearing substrate.This study aimed to investigate the effects of six different pyrethroid and organophosphate insecticides on this insect species'performance.The toxicity of two"model"substances for each of these classes(cypermethrin;pirimiphosmethyl)was quantified,with and without the synergist piperonyl butoxide(PBO).Critical effect doses corresponding to 10%yield(CED10)for cypermethrin(0.4 mg/kg)and pirimiphos-methyl(4.8 mg/kg)were determined.The addition of PBO to cypermethrin enhanced its relative potency with a factor 2.6.These data were compared against the relative toxicity of two analogue substances in each class(permethrin,deltamethrin;chlorpyrifosmethyl,malathion).Results suggest that exposure to concentrations complying with legal limits can cause significant reductions in yield.Exposure to multiple substances at lower concentrations resulted in negative additive and synergistic effects.Of the tested substances,deltamethrin was most toxic,causing 94%yield at 0.5 mg/kg.Analytical results suggested that transfer of tested substances to the larval biomass was substance-and concentration-specific,but appeared to be correlated to reduced yields and the presence of PBO.Transfer of organophosphates was overall low(<2%),but ranged from 8%to 75%for pyrethroids.Due to very low limits in insect biomass(~0.01 mg/kg),high transfer may result in noncompliance.It is recommended that rearing companies implement lower contractual thresholds,and that policymakers consider adjusting legally allowed maximum residue levels in insect feed.
基金supported by National Natural Science Foundation of China(Grant No.12432018,12372346)the Innovative Research Groups of the National Natural Science Foundation of China(Grant No.12221002).
文摘A typical Whipple shield consists of double-layered plates with a certain gap.The space debris impacts the outer plate and is broken into a debris cloud(shattered,molten,vaporized)with dispersed energy and momentum,which reduces the risk of penetrating the bulkhead.In the realm of hypervelocity impact,strain rate(>10^(5)s^(-1))effects are negligible,and fluid dynamics is employed to describe the impact process.Efficient numerical tools for precisely predicting the damage degree can greatly accelerate the design and optimization of advanced protective structures.Current hypervelocity impact research primarily focuses on the interaction between projectile and front plate and the movement of debris cloud.However,the damage mechanism of debris cloud impacts on rear plates-the critical threat component-remains underexplored owing to complex multi-physics processes and prohibitive computational costs.Existing approaches,ranging from semi-empirical equations to a machine learningbased ballistic limit prediction method,are constrained to binary penetration classification.Alternatively,the uneven data from experiments and simulations caused these methods to be ineffective when the projectile has irregular shapes and complicate flight attitude.Therefore,it is urgent to develop a new damage prediction method for predicting the rear plate damage,which can help to gain a deeper understanding of the damage mechanism.In this study,a machine learning(ML)method is developed to predict the damage distribution in the rear plate.Based on the unit velocity space,the discretized information of debris cloud and rear plate damage from rare simulation cases is used as input data for training the ML models,while the generalization ability for damage distribution prediction is tested by other simulation cases with different attack angles.The results demonstrate that the training and prediction accuracies using the Random Forest(RF)algorithm significantly surpass those using Artificial Neural Networks(ANNs)and Support Vector Machine(SVM).The RF-based model effectively identifies damage features in sparsely distributed debris cloud and cumulative effect.This study establishes an expandable new dataset that accommodates additional parameters to improve the prediction accuracy.Results demonstrate the model's ability to overcome data imbalance limitations through debris cloud features,enabling rapid and accurate rear plate damage prediction across wider scenarios with minimal data requirements.
基金Supported by the Shijiazhuang Science and Technology Research and Development Program,No.221460383.
文摘BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current status of family rearing,parental stress,and behavioral and emotional problems of preschool children and to analyze the mediating effect of the current status of family rearing on parental stress and behavioral/emo-tional problems.METHODS We use convenience sampling to select 258 preschool children in the physical examination center of our hospital from October 2021 to September 2023.The children and their parents were evaluated using a questionnaire survey.Pearson's correlation was used to analyze the correlation between child behavioral and emotional problems and parental stress and family rearing,and the structural equation model was constructed to test the mediating effect.RESULTS The score for behavioral/emotional problems of 258 preschool children was(27.54±3.63),the score for parental stress was(87.64±11.34),and the score for parental family rearing was(31.54±5.24).There was a positive correlation between the behavioral and emotional problems of the children and the“hostile/mandatory”parenting style;meanwhile,showed a negative correlation with the“support/participation”parenting style(all P<0.05).The intermediary effect value between the family upbringing of parents in parental stress and children's behavior problems was 29.89%.CONCLUSION Parental family upbringing has a mediating effect between parental stress and behavioral and emotional problems of children.Despite paying attention to the behavioral and emotional problems of preschool-age children,clinical medical staff should provide correct and reasonable parenting advice to their parents to promote the mental health of preschool-age children.
基金Supported by National Innovation and Entrepreneurship Training Program for College Students(202410580010)Construction Project of the Zhaoqing Citrus Comprehensive Experimental Station Platform under the National Modern Agricultural Industry Technology System(202413004)+1 种基金Key Projects of the Second Round Project of High-quality Development in Hundred Counties,Thousands Towns and Ten Thousand Villages for Rural Science and Technology Special Commissioners Dispatched by the Guangdong Provincial Department of Science and Technology(KTP20240684)Doctoral Scientific Research Initiation Fund Project of Zhaoqing University(611/230009).
文摘Citrus is the highest-yielding fruit crop globally,with China ranking first in both cultivation area and production worldwide.During citrus growth,the crop is often damaged by various pests such as Diaphorina citri,scale insects,and aphids.Among these,D.citri,the vector of Huanglongbing(citrus greening disease),is particularly severe and has caused substantial economic losses globally.Currently,chemical pesticides remain the primary method for controlling citrus pests.However,their overuse can lead to pest resistance and excessive pesticide residues,posing threats to human health and the environment.Therefore,utilizing natural enemy insects for biological control is of significant importance.This paper systematically reviewed the research progress in artificial rearing of natural enemy insects for citrus pests,aiming to provide references for green pest management in citrus cultivation and promote the healthy and sustainable development of the citrus industry.
基金supported by the National Natural Science Foundation of China(No.22241603).
文摘Insects have become an efficient and eco-friendly bioreactor for plastics and even micro/nano-plastics biodegradation.However,the optimal conditions for rearing insects to maximize plastic biodegradation and the underlying mechanisms remain unclear,hindering its practical applications.We investigated the effects of multiple rearing factors on plastics degradation efficiency of Tenebrio molitor larvae,including larval instar,water addition frequency,plastic specific surface area and plastic types.The functional gut microbes and enzymes associated with the improved efficiency were further explored.Our findings revealed that adult larvae achieved the highest plastics degradation efficiency when receiving regular water additions without causing drowning of insects on hydrophobic plastics.Additionally,they effectively ingested foam plastics of polystyrene,polyethylene and polyurethane without prior comminution and densification.The biodegradation processes involving oxidation,cleavage and depolymerization of plastics were all demonstrated.Furthermore,foam plastic type-dependent functional microbes and enzymes that contributed to the efficient plastic degradationwere identified.Thiswork provides valuable insights into the practical applications of insects for sustainable plastics biodegradation.
文摘Chouioia cunea Yang is a natural enemy for many kinds of crop and forest pests, particularly for Hyphantria cunea Drary, which is an international quarantine pest. The experiment of rearing Chouioia cunea with Tussah (Silkworm) pupa were carried out by 搕hree-cut method?and inoculating method. The results showed that three-cut method is effective way for breed-ing Chouioia cunea, with a parasitical rate of 95%. The biological characteristics and the life cycle of Chouioia cunea were ob-served and described and more hosts of Chouioia cunea were found. 揟hree-cut method?as a new technique of rearing Chouioia cunea has been put into practice.
文摘[ Objective] The aim of this experiment was to explore the effects of different rearing modes on muscle histological traits and muscle ten demess and to provide theoretical basis for regulating chicken meat quality. [ Method] The effects of outdoor rearing, indoor rearing and cage rea ring modes on the muscular histological traits and meat tenderness of Hetian chicken at the age of 8 weeks, 12 weeks and 16 weeks were re searched. [Result] The results showed that the breast and thigh muscle fibre diameter and muscle shear force of outdoor rearing chicken were sig nificently higher than that of cage rearing chicken ( P 〈 0.05), and muscle fibre density was significantly lower than that of cage rearing chicken ( P 〈 0.05). With aging, the muscle fibre diameter and shear force increased and muscle fibre density decreased ( P 〈 0.05). The muscle fibre di ameter and shear force of male were higher than that of female. The correlation analysis showed that the breast muscle shear force had a signifi cantly positive relation with fibre diameter and negative relation with fibre density ( P 〈 0.05), but thigh muscle shear force had an insignificantly pos itive relation with fibre diameter and fibre density. [ Condusion] Muscular histological traits varied in different rearing modes, and the outdoor rearing promoted the muscular fibre development and increased the muscular shear force.
基金funded by the National Nature Science Foundation of China(Grant No.31172067)the National Nature Science Foundation of China-Guang dong Joint Fund(U0833005)Guangdong Plan Projects(2010B060200034,2011B031100004)
文摘The White-eared Night Heron (Gorsachius magnificus) is a Class II protected species in China. It is difficult to observe in the field and its population is small. The present study reports a new distribution site in Nanxiong County, in northern Guangdong Province, where observations of an active nest were made from 4 May to 14 July 2012, the first time consecutive observations have been made for a period of more than two months. The adults flew away from the nest at night, with a peak at 19:00-20:00 and returned in the mornings with a peak at 04:30-05:30. The peak time for feeding young was at 05:00-05:30, accounting for 26.5%of total feeding activities. No feeding occurred from 10:00 to 16:00. The results of our study of its behavior explain why the White-eared Night Heron is usually observed in the evening just before dark, or in the morning before sunrise, at least during the breeding season. There were about 67 days from hatching to fledging, longer than the fledging time of most heron species. This study is the first to cover the entire period of parental care and fills a gap in previous knowledge.
基金Supported by Scientific and Technological Project of Jiangsu Province (BE2005350)~~
文摘[ Objective] The aim was to supply technical basis for developing quarantine and control techniques for orient fruit fly. [ Method] By utilizing facilities including rearing chamber and rearing cage, the population of orient fruit fly was established and sustained by using the methods of artificial feeding and fruit culture, and the continuous indoor biological observation was carried out. The isolated enclosure equipped with temperature and humidity recorder was established in Dongshan area of Taihu for cultivating various species of host plants, then the living habits of orient fruit fly were observed everyday. [ Result] Through feeding and observation in lab, the living habit of adult, larva, pupa and eggs of orient fruit fly were studied; the impact of soil depth on the emergence rate of pupa were conducted, and the result indicated that when the soil layer depth increased to 40 cm, there were still adults appeared and their emergence rate was 80%. The results of indoor trend test showed that the selectivity of orient fruit fly on fruits produced in Suzhou was sequenced from high to low as follows: tangerine, dates, pomegranate, peach, orange, pear and persimmon. While the sequence of fruit tree species were tangerine, dates, pomegranate, pears and persimmons according to damage rates of orient fruit fly from high to low under field isolation rearing conditions. In the local tangerine varieties, the damage rate from high to low were Dongting manda- rin, eady tangerine, Wen orange, Huangpi, Zaohong, Liaohong. [ Conclusion] Orient fruit fly artificial rearing facility was established, which laid the foundation for carrvina out bioloaical characteristics observation and biolooical exoeriments
文摘[Objective] The aim was to seek the optimal choice of hormones,induced temperature,and initial feed for cultivating loach.[Method] Different hormones were injected to Ioaches for artificial reproduction in water at different temperatures.During cultivation,varied initial feeds were put in to explore the optimal choice of hormones,temperature and initial feed.[Result] According to the test,fecundity of female loach is directly proportional to gonad maturity,namely,the higher gonad maturity,the more fecundity.For example,for a female loach whose maturity coefficient was 24%,absolute and relative fecundity rates were 62 142 and 990.In contrast,for a female whose maturity coefficient was 9%,the rates were 18 207 and 367,respectively.The induced effect differs upon hormones and the test demonstrated that LRH-A2 is better in improving fertility rate compared with HCG.For example,the fertility rate in the group with HCG was 78.84 and in the group with LRH-A2 was 83.04%.It is notable that the mixture of the two at a certain ratio would enhance induced effect and the fertility rate can be as high as 89.17%.With temperature in a certain range,the higher temperature,the better induced effect.The test indicated that water temperature at (30±0.5) ℃ is an optimal one and the effect horizon is 6-8 h.In group 4,induced rate was 93.33% and the fertility rate was 89.26%.The research indicated that the survival rate was the highest if wheel animalcule,dominated by Brachionus calyciflorus and Brachionus angularis,was taken as an initial feed,followed by artemia nauplii and corpuscule.In addition,loach fry in the group with yolk and wheel animalcule grew about 1.21 times than the group with only yolk,1.04 times than the group with only fairy shrimp,and 1.1 times than the group with fairy shrimp.[Conclusion] The research provides scientific references for scale loach farming.
基金Supported by Key Technologies of R&D Program of Shanxi Province(20120311019-1)Research Project Supported by Shanxi Scholarship Council of China(2012-110)+1 种基金Doctoral Research Fund of Shanxi Academy of Agricultural Sciences(YBSJJ1006)Key Technologies of R&D Program of Shanxi Academy of Agricultural Sciences(2012ygg16)~~
文摘[Objective] The research aimed to optimize laboratory artificial rearing methods for Plutella xylostella L. and to select out effective insecticides against this pest species. [Method] Brassica chinensis seedlings were cultivated in the laboratory at (25±1)℃, 60-75% RH, and a photoperiod of 14:10 (L:D) h. The green blow molding papers were used to collect eggs, and Brassica oleracea seedlings were cultivated to breed Plutella xylostella L. until the insects were ready for use. Mean-while, the susceptibility of 3rd instar larvae of Plutella xylostella L. to five types of insecticides was tested by leaf-dipping method. [Result] Plutella xylostella L. larvae were found well-grown and uniform in developmental stages with average pupa weight of 5.4 mg, pupa emergence percentage of 94.0 % and egg number of 135.1 per female. The LCso values of 3rd instar Plutella xylostella L. larvae against 200 g/L chlorantraniliprole SC, 20% flubendiamide WG, 150 g/L indoxacarb EC, 200 g/L tebufenozide SC and 1.8% abamectin EC, were 0.152, 0.223, 1.151, 93.340 and 0.128 mg/L, respectively. [Conclusion] This rearing method is easy to be implemented and of great practicality, suitable for mass propagation of P. xylostella L. Abamectin, chlorantraniliprole and flubendiamide showed high insecticidal activities, so these three insecticides can be used alternately for the field prevention and control of Plutella xylostella L.
文摘In the White sturgeon fish farms, some individuals have difficulty in getting access to food: such sturgeons are called "runts", and they result in a slower growth rate than normally feeding fish. In this paper, we have studied the gut peculiarities of runt sturgeons. Utilizing in paralleling an analysis of diatom populations in both the fish gut tissues and the rearing tank waters, we hypothesized a causative relation between the occurrence of runt sturgeons and periodic diatom blooms. In fact, we have observed that the diatom species identified in the aquatic environment were also detected in organs (Fragilaria spp and Rhoicosfenia spp for both glandular body, mid-intestine) of the runt sturgeon's gut, but not in tissues of normally feeding individuals. Owing to their siliceous wall, diatoms can be responsible for areas of epithetlial detachment in the mucosal surfaces of the alimentary canal and a catharral inflammation in both the gastric pits and intestinal folds which may be the cause of secondary bacterial diseases. We suggest that diatom blooms may contribute to the occurrence of runt sturgeons in the studied Italian fish farm.
基金funded by the Collaborative Innovation Task of the Agricultural Science and Technology Innovation Program in Chinese Academy of Agricultural Sciences (CAAS)the Fundamental Research Funds for Central Non-profit Scientific Institution of CAAS
文摘Calves are the reserve forces for dairy cattle. Scientific rearing strategy of calves is the basis of efficient cattle breeding. However, many problems exist in current rearing systems of calves and restrict the sustainable development of dairy cattle in China. The absence of basic research is the most highlighted problem among them. Recent researches on growth performance, nutrient digestibility, blood biochemical indices and rumen development in calves were summarized in this paper. Additionally, the optimal levels of energy and protein in milk replacer and starter diets for calves were indicated, and limiting amino acids for calves fed different diets were discussed. A variety of additives, such as acidifiers, probiotics and polysaccharides, are regarded as promising alternatives to antibiotics to reduce disease in calves. Dietary supplementations of these additives have positive effects on growth and health of calves. However, studies on the nutrition of vitamins and minerals in calves have been seldom done, and deserve our further researches. To sum up, the postnatal period is one of the most critical “windows” for rumen manipulation and epigenetic regulation. Any changes from environments, especially early nutrition, may produce long-term effects on growth, health and milk yields in adult cattle.
基金supported by the National Natural Science Foundation of China (41161140352, 41471092)
文摘Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data of Taibus Banner, Duolun county and Zhengxiangbai Banner in the Inner Mongolia autonomous region of China, we identified the impact of livelihood diversification on ecosystems in these agro-pastoral areas by using the ecological footprint theory and methodology together with the one-way analysis of variance (ANOVA) and correlation analysis methods. In 2011, the total ecological footprint of consumption (EFC) was 0.665 g hm2, and the total ecological footprint of production (EFP) was 2.045 g hm2, which was more than three times the EFC. The ecological footprint of arable land consumption (EFAC) accounted for a large proportion of the EFC, and the ecological footprint of grassland production (EFGP) occupied a large proportion of the EFP. Both the ecological footprint of grassland consumption (EFGC) and EFGP had a significant positive correlation with the income, indicating that income was mainly depended on livestock production and the households with higher incomes consumed more livestock prod- ucts. The full-time farming households (FTFHs) had the highest EFP, ecological footprint of arable land production (EFAP), EFGP and EFGC, followed by the part-time farming households (PTFHs) and non-farming households (NFHs), which indicated that part-time farming and non-farming employment reduced the occupancy and con- sumption of rural households on local ecosystems and natural resources to some extent. When farming households engaged in livestock rearing, both the EFAP and EFAC became smaller, while the EFP, EFC, EFGC and EFGP increased significantly. The differences in ecological footprints among different household groups should be taken into account when making ecosystem conservation policies. Encouraging the laborers who have the advantages of participating in non-farming employment to move out of the rural areas and increasing the diversification of liveli- hoods of rural households are important in reducing the environmental pressures and improving the welfare of households in the study area. Moreover, grassland should be utilized more effectively in the future.
基金Project(2017QNA21)supported by the Fundamental Research Funds for the Central Universities of ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China
文摘Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural properties and filed application of backfill hydraulic support,this work has firstly proposed the basic principle of backfill hydraulic support optimization design and provided the method of optimal design of key structural components,like four-bar linkage,rear canopy and tamping structure;the method is further elaborated as changing hinging position of upper bar to optimize four-bar linkage,by lengthening or shortening the rear canopy to optimize length ratio of canopy;and by changing length and hinging position of tamping structure as well as suspension height of backfill scrape conveyor to realize optimization of tamping structure.On this basis,the process of optimal design of backfill hydraulic support is built.The optimal design case of ZC5200/14.5/30 six columns-four bar linkage used in 7203 W workface of Zhaizhen Coal Mine shows that the backfill properties like horizontal roof gap,vertical horizontal gap,tamping angle and tamping head gap are improved obviously through optimizing four-bar linkage,canopy length and tamping structure according to the optimal design method proposed in this work.
基金Project supported by the National Natural Science Foundation of China(Nos.31101783 and 31472164)the Special Fund for Independent Innovation of Agricultural Science and Technology in Jiangsu Province of China(No.CX(13)3070)
文摘Experiments were conducted to study the effects of dietary taurine and housing density on oviduct function in laying hens. Green-shell laying hens were randomly assigned to a free range group and two caged groups, one with low-density and the other with high-density housing. Each group was further divided into control(C) and taurine treatment(T) groups. All hens were fed the same basic diet except that the T groups' diet was supplemented with 0.1% taurine. The experiment lasted 15 d. Survival rates, laying rates, daily feed consumption, and daily weight gain were recorded. Histological changes, inflammatory mediator levels, and oxidation and anti-oxidation levels were determined. The results show that dietary taurine supplementation and reduced housing density significantly attenuated pathophysiological changes in the oviduct. Nuclear factor-κB(NF-κB) DNA binding activity increased significantly in the high-density housing group compared with the two other housing groups and was reduced by taurine supplementation. Tumor necrosis factor-α(TNF-α) m RNA expression in the high-density and low-density C and T groups increased significantly. In the free range and low-density groups, dietary taurine significantly reduced the expression of TNF-α m RNA. Supplementation with taurine decreased interferon-γ(IFN-γ) m RNA expression significantly in the low-density groups. Interleukin 4(IL-4) m RNA expression was significantly higher in caged hens. IL-10 m RNA expression was higher in the high-density C group than in the free range and low-density C groups. Supplementation with taurine decreased IL-10 m RNA expression significantly in the high-density group and increased superoxide dismutase(SOD) activity in the free range hens. We conclude that taurine has important protective effects against oviduct damage. Reducing housing density also results in less oxidative stress, less inflammatory cell infiltration, and lower levels of inflammatory mediators in the oviduct. Therefore, both dietary taurine and reduced housing density can ameliorate oviduct injury, enhance oviduct health, and promote egg production in laying hens.
基金supported by National Major Science and Technology Projects of China(J2019-Ⅱ-0007-0027)Fundamental Research Funds for the Central Universities,China(3082018NP2018102)+1 种基金National Natural Science Foundation of China(12002162)Jiangsu Province Natural Science Foundation,China(BK20200449)。
文摘In this study,firstly,for the axisymmetric RVABI,the change-rule of adverse pressure gradient caused by radial velocity during the transition of internal flow mode in variable geometry is summarized,and a Bypass Ratio(BR) iterative algorithm based on the empirical correlation of non-equilibrium pressure is proposed.The algorithm can estimate the nonlinear relationship between area ratio and BR,with an error range falling below 6.5%.Then,we discuss the favorable effect of uniform mixing on the thrust augmentation of mixed exhaust under variable BR conditions.From this point of view,the characteristics of vortices evolution in different shear strength jets are compared,to clarify the effect of variable cycle parameters on jet mixing.As the results suggest,when ■ is as low as 0.22,the K-H disturbance is of high-frequency wavelet property,and it is difficult to induce large-scale spanwise vortices.The macro migrations of fluid elements in span wise vortices and the diffusion effect caused by edge tearing is weak,which is not conducive to the energy exchange between the two streams.However,the low ■ jet will also correspondingly weaken the viscous dissipation effect of vortices.It is concluded that the dissipation level is proportional to the 2.31 power of the ■.
文摘Objective:Empathy can help establish harmonious nurse-patient relationships.We aimed to assess the status of empathy,and explore the relationship between learning burnout,parental rearing patterns and empathy amongst nursing students.Method:A questionnaire survey that employed the Learning Burnout Scale,the Short-Form Egna Minnenav Barndoms Uppfostran(s-EMBU)and the Jefferson Scale of Empathy was conducted amongst 562 nursing students.The data were analysed on the basis of descriptive statistic and correlation analysis was used.Results:Empathy is negatively correlated with learning burnout,parental rejection and overprotection and showed no positive correlation with parental emotional warmth.Conclusions:Educators should pay attention to nursing students'feelings and learning burnout status and take positive measures to improve the empathy level of the students.Positive parental rearing patterns also help cultivate empathy.