Protein haze was one of the main causes of the instability of white wines. Proteins that caused haze or precipitation in white wines mainly came from grape fruits, and their compositions and contents were affected by ...Protein haze was one of the main causes of the instability of white wines. Proteins that caused haze or precipitation in white wines mainly came from grape fruits, and their compositions and contents were affected by many factors such as fruit diseases, harvesting methods and water stress. Unstable wine proteins were usually pathogenesis-related(PR)proteins of grapes, mainly chitinases and thaumatin-like proteins(TLPs), which had lower isoelectric point(pI)and smaller molecular weight, and were highly resistant to the low pH values of wines and the protease hydrolysis during fermentation. At present, the technology of protein stabilization and clarification in white wines mainly included bentonite fining, heat treatment, enzymatic hydrolysis, polysaccharide treatment and ultrafiltration methods. Among them, the most commonly used method was bentonite treatment. In this paper, the research progresses of the origin, mechanism and influencing factors of the unstable proteins in white wines were summarized, and the applications, advantages and disadvantages of various clarification techniques were also concluded, in order to provide some support for the theoretical and technological research of the protein stability in white wines in the future.展开更多
Background: Bringing free-living animals into captivity subjects them to the stress of both capture and captivity, leading to the alteration of normal physiological processes and behaviors through activation of the hy...Background: Bringing free-living animals into captivity subjects them to the stress of both capture and captivity, leading to the alteration of normal physiological processes and behaviors through activation of the hypothalamic– pituitary–adrenal axis. In free-living birds, although elevated plasma corticosterone (CORT) is an important adaptation regulating physiological and behavioral responses during the process of capture and captivity stress, little information is currently available on the effects of such stress on plasma metabolite levels. Methods: We examined the effects of immediate capture and 24-h captivity on body mass, body condition, plasma CORT, and metabolite levels including glucose (Glu), triglyceride (TG), total cholesterol (TC), uric acid (UA), in breeding Eurasian Tree Sparrows (Passer montanus). Results: CORT and Glu levels were increased significantly by the stress of capture, whereas TC and UA levels decreased. Body mass, body condition declined notably after 24 h in captivity, but CORT, Glu, and UA levels increased. Furthermore, male sparrows had lower TG levels after both capture and captivity than those of females. The relationships between plasma CORT and metabolite levels varied between sexes. Conclusions: Our results revealed that the metabolic status of Eurasian Tree Sparrows could be dramatically altered by capture and captivity. Monitoring the dynamic effects of both capture and captivity on plasma CORT, metabolite levels in a free-living bird contributes to a better understanding of the stress-induced pathways involved in sexdependent energy mobilization.展开更多
Background: Geographic variation in body size is assumed to reflect adaptation to local environmental conditions. Although Bergmann's rule is usually sufficient to explain such variation in homeotherms, some excep...Background: Geographic variation in body size is assumed to reflect adaptation to local environmental conditions. Although Bergmann's rule is usually sufficient to explain such variation in homeotherms, some exceptions have been documented. The relationship between altitude, latitude and body size, has been well documented for some vertebrate taxa during the past decades. However, relatively little information is available on the effects of climate variables on body size in birds.Methods: We collected the data of 267 adult Eurasian Tree Sparrow(Passer montanus) specimens sampled at 48 localities in China's mainland, and further investigated the relationships between two response variables, body mass and wing length, as well as a suit of explanatory variables, i.e. altitude, latitude, mean annual temperature(MAT), annual precipitation(PRC), annual sunshine hours(SUN), average annual wind speed(WS), air pressure(AP) and relative humidity(RH).Results: Our study showed that(1) although the sexes did not differ significantly in body mass, males had longer wings than females;(2) body mass and wing length were positively correlated with altitude but not with latitude;(3) body mass and wing length were negatively correlated with AP and RH, but not significantly correlated with WS. Body mass was positively correlated with SUN and inversely correlated with MAT. Wing length was not correlated with MAT in either sex, but was positively correlated with SUN and negatively correlated with PRC in male sparrows;(4) variation in body mass could be best explained by AP and SUN, whereas variation in wing length could be explained by RH and AP in both sexes. In addition, variation in male sparrows can be explained by SUN, WS and PRC but not in females.Conclusions: Two different proxies of body size, body mass and wing length, correlated with same geographic factors and different climate factors. These differences may reflect selection for heat conservation in the case of body mass, and for efficient flight in the case of wing length.展开更多
Background:Efficient and selective utilization of metabolic substrates is one of the key strategies in high-altitude animals to cope with hypoxia and hypothermia.Previous findings have shown that the energy substrate ...Background:Efficient and selective utilization of metabolic substrates is one of the key strategies in high-altitude animals to cope with hypoxia and hypothermia.Previous findings have shown that the energy substrate utilization of highland animals varies with evolutionary history and phylogeny.The heart is a proxy for the cardiopulmonary system,and the metabolic substrate utilization in the myocardium is also under the strong selective pressure of chronically hypoxic and hypothermic environments.However,little information is available on the physiological adjustments in relation to metabolic substrate utilization in the myocardium for coping with high-altitude environments.Methods:We compared the metabolic enzyme activities,including hexokinase(HK),phosphofructokinase(PFK),pyruvate kinase(PK),citrate synthase(CS),carnitine palmitoyl transferase 1(CPT-1),lactic dehydrogenase(LDH),and creatine kinase(CK),and metabolic substrate contents including glucose(Glu),triglyceride(TG),and free fatty acid(FFA)in the myocardium of a typical human commensal species,Eurasian Tree Sparrows(Passer montanus)between the Qinghai-Tibet Plateau(the QTP,3230 m)and low altitude population(Shijiazhuang,80 m),and between sexes.Results:Among the seven metabolic enzymes and three substrates investigated,we identified no significant differences in PK,CPT-1,HK,CS,LDH,and CK activities and TG content of the myocardium between high and low altitude populations.However,the QTP sparrows had significantly lower Glu content and PFK activities but higher FFA content relative to their lowland counterparts.In addition,male sparrows had higher myocardial HK and CS activities relative to females,independent of altitude.Conclusions:Our results showed that the QTP sparrows elevated fatty acid utilization rather than glucose preference in the myocardium relative to lowland counterpart,which contributes to uncovering both the physiological adjustments for adapting to the extreme conditions of the QTP,intraspecifically.展开更多
Background: Passerida is the largest avian radiation within the order Passeriformes. Current understanding of the high-level relationships within Passerida is based on DNA–DNA hybridizations; however, the phylogeneti...Background: Passerida is the largest avian radiation within the order Passeriformes. Current understanding of the high-level relationships within Passerida is based on DNA–DNA hybridizations; however, the phylogenetic relationships within this assemblage have been the subject of many debates.Methods: We analyzed the 12 S ribosomal RNA gene from 49 species of Passerida, representing 14 currently recognized families, to outline the phylogenetic relationships within this group.Results: Our results identified the monophyly of the three superfamilies in Passerida: Sylvioidea, Muscicapoidea and Passeroidea. However, current delimitation of some species is at variance with our phylogeny estimate. First, the Parus major, which had been placed as a distinct clade sister to Sylvioidea was identified as a member of the super family;second, the genus Regulus was united with the Sturnidae and nested in the Muscicapoidea clade instead of being a clade of Passerida.Conclusion: Our results were consistent with Johansson's study of the three superfamilies except for the al ocation of two families, Paridae and Regulidae.展开更多
Background:Unlike resident birds,migratory birds are generally believed to have evolved to enhance flight efficiency;however,direct evidence is still scarce due to the difficulty of measuring the flight speed and mech...Background:Unlike resident birds,migratory birds are generally believed to have evolved to enhance flight efficiency;however,direct evidence is still scarce due to the difficulty of measuring the flight speed and mechanical power.Methods:We studied the differences in morphology,flight kinematics,and energy cost between two passerines with comparable size,a migrant(Fringilla montifringilla,Brambling,BRAM),and a resident(Passer montanus,Eurasian Tree Sparrow,TRSP).Results:The BRAM had longer wings,higher aspect ratio,lower wingbeat frequency,and stroke amplitude compared to the TRSP despite the two species had a comparable body mass.The BRAM had a significantly lower maximum speed,lower power at any specific speed,and thus lower flight energy cost in relative to the TRSP although the two species had a comparable maximum vertical speed and acceleration.Conclusions:Our results suggest that adaptation for migration may have led to reduced power output and maximum speed to increase energy efficiency for migratory flight while residents increase flight speed and speed range adapting to diverse habitats.展开更多
Human commensal species take advantage of anthropogenic conditions that are less likely to be challenged by the selective pressures of natural environments.Their morphological and physiological phenotypes can therefor...Human commensal species take advantage of anthropogenic conditions that are less likely to be challenged by the selective pressures of natural environments.Their morphological and physiological phenotypes can therefore dissociate from habitat characteristics.Understanding how these species adjust their morphological and physiological traits across latitudinal gradients is fundamental to uncovering the eco-physiological strategies underlying coping mechanisms.Here,we studied morphological traits in breeding Eurasian tree sparrows(ETSs;Passer montanus)among low-latitude(Yunnan and Hunan)and middle-latitude(Hebei)localities in China.We then compared body mass;lengths of bill,tarsometatarsus,wing,total body,and tail feather;and baseline and capture stress-induced levels of plasma corticosterone(CORT)and the metabolites including glucose(Glu),total triglyceride(TG),free fatty acid(FFA),total protein,and uric acid(UA).None of the measured morphological parameters varied with latitude except in the Hunan population,which demonstrated longer bills than those in other populations.Stress-induced CORT levels significantly exceeded baseline levels and decreased with increasing latitude,but total integrated CORT levels did not vary with latitude.Capture stress-induced significantly increased Glu levels and decreased TG levels,independent of site.However,the Hunan population had significantly higher baseline CORT,baseline and stress-induced FFA levels,but lower UA levels,which differed from other populations.Our results suggest that rather than morphological adjustments,physiological adjustments are mainly involved in coping mechanisms for middle-latitude adaptation in ETSs.It is worth investigating whether other avian species also exhibit such dissociation from external morphological designs while depending on physiological adjustments.展开更多
On the Qinghai-Tibet Plateau,extreme environmental conditions have imposed intense selective pressure on the evolution of phenotypic traits of wild animals.To date,limited information is available on behavioral and ec...On the Qinghai-Tibet Plateau,extreme environmental conditions have imposed intense selective pressure on the evolution of phenotypic traits of wild animals.To date,limited information is available on behavioral and ecological traits concerning niche differentiation among sympatric animals on the Qinghai-Tibet Plateau,especially during winter when the environments are most severe.Here,we studied the seasonal variations in habitat occurrence,territorial behavior,and diet in two sympatric snow finches(the white-rumped snow finch,Onychostruthus taczanowskii,WRSF;and the rufous-necked snow finch,Pyrgilauda ruficollis,RNSF)to determine convergence and divergence of ecological traits in such severe climatic conditions.Our results showed that:(i)WRSF occupied rural areas as a dominant species throughout the annual cycle while RNSF occupied the rural areas in summer and then shifted to human-occupied areas in winter and spring;(ii)WRSFs exhibited robust aggressive behavior and territoriality during winter relative to RNSFs;(iii)the diets of both species varied with the season but did not vary between species except that WRSF ate significantly more seeds but RNSF consumed more starchy material derived from human food waste during winter.Therefore,the separations in the spatial niche and territoriality between WRSF and RNSF,especially in winter,may contribute to alleviating the pressure of interspecific competition,and promoting the coexistence of the two sympatric snow finches in the extreme environments on the Qinghai-Tibet Plateau.展开更多
Two consecutive trials were conducted to investigate the effects of glucosinolates(GLS)in rapeseed cake(RSC)on nitrogen(N)metabolism and urine nitrous oxide(N_(2)O)emissions in steers.In trial 1,8 steers and 4 levels ...Two consecutive trials were conducted to investigate the effects of glucosinolates(GLS)in rapeseed cake(RSC)on nitrogen(N)metabolism and urine nitrous oxide(N_(2)O)emissions in steers.In trial 1,8 steers and 4 levels of RSC,i.e.0,2.7%,5.4%and 8.0%dry matter(DM)(0,6.0,12.1,18.1 mmol GLS/g DM)were allocated in a replicated 4×4 Latin square.In trial 2,the static incubation technique was used for measuring the N_(2)O emissions of the urine samples collected from trial 1.The results of trial 1 indicated that dietary inclusion of RSC decreased the digested N and increased the fecal N excretion(P<0.01),whereas it did not affect the urinary N excretion,total N excretion and N retention(P>0.10).Dietary inclusion of RSC decreased the urinary excretion of urea while it increased allantoin,total purine derivatives,the predicted rumen microbial N flow and thiocyanate(SCN)(P<0.05).Dietary inclusion of RSC did not affect the plasma triiodothyronine and thyroxine while it down-regulated the plasma relative concentrations of 4-aminohippuric acid,3a,7a-dihydroxycoprostanic acid,phosphatidylserine(14:0/16:0),6b-hydroxyprogesterone,pyrrhoxanthinol,tatridin B,mandelonitrile rutinoside,taraxacoside(P<0.05),and up-regulated hypoglycin B,neuromedin N(1-4),dhurrin,5-deoxykievitone(P<0.01).The results of trial 2 indicated that dietary RSC increased the steer urine N_(2)OeN fluxes,the ratio of N_(2)OeN to N application and the estimated steer urine N_(2)OeN emissions(P<0.01).A close correlation was found between the estimated steer urine N_(2)OeN emissions and the output of urinary SCN(P<0.001).In conclusion,dietary RSC increased the fecal N excretion,whereas it did not affect the urinary N excretion and the N retention rate in steers.Dietary RSC increased rather than decreased the urine N_(2)OeN emissions even though it decreased the urinary excretion of urea.The SCN excreted in urine could be the major factor in increasing the urine N_(2)OeN emissions.Whether other metabolites excreted into urine from RSC have an impact on the urine N_(2)OeN emissions in steers needs to be investigated in the future.展开更多
Rivers and their lakes are among the world’smost important ecosystems supporting high biodiversity and providing various services through connections with vast landscapes.Reconciling exploitation with sustainability ...Rivers and their lakes are among the world’smost important ecosystems supporting high biodiversity and providing various services through connections with vast landscapes.Reconciling exploitation with sustainability remains one of the world’s greatest challenges tomaintain and/or recover the health of river ecosystems and hence their biodiversity and ecosystem services.1 As one of the major national initiatives toward building“ecological civilization”and an extensive protection of the Yangtze River in China,a“10-year fishing ban”plan(TYFB)was launched from January 2021.展开更多
The cell-derived extracellular matrix(ECM)-modified scaffolds have advantages of mimic tissue specificity and been thought to better mimic the native cellular microenvironment in vitro.ECM derived from cardiac fibrobl...The cell-derived extracellular matrix(ECM)-modified scaffolds have advantages of mimic tissue specificity and been thought to better mimic the native cellular microenvironment in vitro.ECM derived from cardiac fibroblasts(CFs)are considered as key elements that provide a natural cell growth microenvironment and change the fate of cardiomyocytes(CMs).Here,a new hybrid scaffold is designed based on silk fibroin(SF)scaffold and CFs-derived ECM.CFs were seeded on the SF scaffold for 10days culturing and decellularized to produce CFs-derived ECM-coated SF scaffold.The results showed that the cell-derived ECM-modified silk fibroin scaffold material contained collagen,laminin,fibronectin and other ECM components with myocardial-like properties.Further to explore its effects on brown adipose stem cells(BASCs)differentiation into CMs.We found that the CFderived ECM-coated scaffold also increased the expression of CM-specific proteins(e.g.cardiac troponin T and α-actinin)of BASCs.Notably,the b1-integrin-dependent transforming growth factor-β1 signaling pathway was also involved in the regulation of CF-derived ECM by promoting the differentiation of BASCs into CMs.Overall,these findings provide insights into the bionic manufacturing of engineered cardiac tissues(ECTs)and establish a theoretical basis for the construction of ECTs.展开更多
基金The financial support of this work was received from China Agriculture Research System for Grape Industry (CARS-29)。
文摘Protein haze was one of the main causes of the instability of white wines. Proteins that caused haze or precipitation in white wines mainly came from grape fruits, and their compositions and contents were affected by many factors such as fruit diseases, harvesting methods and water stress. Unstable wine proteins were usually pathogenesis-related(PR)proteins of grapes, mainly chitinases and thaumatin-like proteins(TLPs), which had lower isoelectric point(pI)and smaller molecular weight, and were highly resistant to the low pH values of wines and the protease hydrolysis during fermentation. At present, the technology of protein stabilization and clarification in white wines mainly included bentonite fining, heat treatment, enzymatic hydrolysis, polysaccharide treatment and ultrafiltration methods. Among them, the most commonly used method was bentonite treatment. In this paper, the research progresses of the origin, mechanism and influencing factors of the unstable proteins in white wines were summarized, and the applications, advantages and disadvantages of various clarification techniques were also concluded, in order to provide some support for the theoretical and technological research of the protein stability in white wines in the future.
基金supported by the National Natural Science Foundation of China(NSFC,31672292)the Natural Science Foundation of Hebei Province(C2017205059)+1 种基金the foundation of China Scholarship Council(201408130068) to D.Lithe NSFC(31770445)to Y.Wu,the NSFC(31372201)to X.Gao
文摘Background: Bringing free-living animals into captivity subjects them to the stress of both capture and captivity, leading to the alteration of normal physiological processes and behaviors through activation of the hypothalamic– pituitary–adrenal axis. In free-living birds, although elevated plasma corticosterone (CORT) is an important adaptation regulating physiological and behavioral responses during the process of capture and captivity stress, little information is currently available on the effects of such stress on plasma metabolite levels. Methods: We examined the effects of immediate capture and 24-h captivity on body mass, body condition, plasma CORT, and metabolite levels including glucose (Glu), triglyceride (TG), total cholesterol (TC), uric acid (UA), in breeding Eurasian Tree Sparrows (Passer montanus). Results: CORT and Glu levels were increased significantly by the stress of capture, whereas TC and UA levels decreased. Body mass, body condition declined notably after 24 h in captivity, but CORT, Glu, and UA levels increased. Furthermore, male sparrows had lower TG levels after both capture and captivity than those of females. The relationships between plasma CORT and metabolite levels varied between sexes. Conclusions: Our results revealed that the metabolic status of Eurasian Tree Sparrows could be dramatically altered by capture and captivity. Monitoring the dynamic effects of both capture and captivity on plasma CORT, metabolite levels in a free-living bird contributes to a better understanding of the stress-induced pathways involved in sexdependent energy mobilization.
基金supported by grants from the National Natural Science Foundation of China (NSFC, 31330073, 31672292)the Natural Science Foundation of the Department of Education, Hebei Province (YQ2014024)
文摘Background: Geographic variation in body size is assumed to reflect adaptation to local environmental conditions. Although Bergmann's rule is usually sufficient to explain such variation in homeotherms, some exceptions have been documented. The relationship between altitude, latitude and body size, has been well documented for some vertebrate taxa during the past decades. However, relatively little information is available on the effects of climate variables on body size in birds.Methods: We collected the data of 267 adult Eurasian Tree Sparrow(Passer montanus) specimens sampled at 48 localities in China's mainland, and further investigated the relationships between two response variables, body mass and wing length, as well as a suit of explanatory variables, i.e. altitude, latitude, mean annual temperature(MAT), annual precipitation(PRC), annual sunshine hours(SUN), average annual wind speed(WS), air pressure(AP) and relative humidity(RH).Results: Our study showed that(1) although the sexes did not differ significantly in body mass, males had longer wings than females;(2) body mass and wing length were positively correlated with altitude but not with latitude;(3) body mass and wing length were negatively correlated with AP and RH, but not significantly correlated with WS. Body mass was positively correlated with SUN and inversely correlated with MAT. Wing length was not correlated with MAT in either sex, but was positively correlated with SUN and negatively correlated with PRC in male sparrows;(4) variation in body mass could be best explained by AP and SUN, whereas variation in wing length could be explained by RH and AP in both sexes. In addition, variation in male sparrows can be explained by SUN, WS and PRC but not in females.Conclusions: Two different proxies of body size, body mass and wing length, correlated with same geographic factors and different climate factors. These differences may reflect selection for heat conservation in the case of body mass, and for efficient flight in the case of wing length.
基金supported by the National Natural Science Foundation of China(NSFC,No.31971413)to DL and NSFC(No.31770445)to YWthe Second Tibetan Plateau Scientific Expedition and Research Program(STEP,2019QZKK0501)+2 种基金the Natural Science Foundation of Hebei Province(NSFHB,C2020205038)to DLthe Foundation of Hebei Normal University(L2019B26)to CJthe Post-doctoral Research Programm to PD。
文摘Background:Efficient and selective utilization of metabolic substrates is one of the key strategies in high-altitude animals to cope with hypoxia and hypothermia.Previous findings have shown that the energy substrate utilization of highland animals varies with evolutionary history and phylogeny.The heart is a proxy for the cardiopulmonary system,and the metabolic substrate utilization in the myocardium is also under the strong selective pressure of chronically hypoxic and hypothermic environments.However,little information is available on the physiological adjustments in relation to metabolic substrate utilization in the myocardium for coping with high-altitude environments.Methods:We compared the metabolic enzyme activities,including hexokinase(HK),phosphofructokinase(PFK),pyruvate kinase(PK),citrate synthase(CS),carnitine palmitoyl transferase 1(CPT-1),lactic dehydrogenase(LDH),and creatine kinase(CK),and metabolic substrate contents including glucose(Glu),triglyceride(TG),and free fatty acid(FFA)in the myocardium of a typical human commensal species,Eurasian Tree Sparrows(Passer montanus)between the Qinghai-Tibet Plateau(the QTP,3230 m)and low altitude population(Shijiazhuang,80 m),and between sexes.Results:Among the seven metabolic enzymes and three substrates investigated,we identified no significant differences in PK,CPT-1,HK,CS,LDH,and CK activities and TG content of the myocardium between high and low altitude populations.However,the QTP sparrows had significantly lower Glu content and PFK activities but higher FFA content relative to their lowland counterparts.In addition,male sparrows had higher myocardial HK and CS activities relative to females,independent of altitude.Conclusions:Our results showed that the QTP sparrows elevated fatty acid utilization rather than glucose preference in the myocardium relative to lowland counterpart,which contributes to uncovering both the physiological adjustments for adapting to the extreme conditions of the QTP,intraspecifically.
基金supported by the National Natural Science Foundation of China (NSFC, 31000191, 31330073)the Postdoctoral Science Foundation of China (2011 M500537)+2 种基金the Natural Science Foundation of Hebei Province (NSFHB, 2012205018)the Natural Science Foundation of the Department of Education, Hebei Province (YQ2014024) to D. LiNSFHB (2013205018) to Y. Wu
文摘Background: Passerida is the largest avian radiation within the order Passeriformes. Current understanding of the high-level relationships within Passerida is based on DNA–DNA hybridizations; however, the phylogenetic relationships within this assemblage have been the subject of many debates.Methods: We analyzed the 12 S ribosomal RNA gene from 49 species of Passerida, representing 14 currently recognized families, to outline the phylogenetic relationships within this group.Results: Our results identified the monophyly of the three superfamilies in Passerida: Sylvioidea, Muscicapoidea and Passeroidea. However, current delimitation of some species is at variance with our phylogeny estimate. First, the Parus major, which had been placed as a distinct clade sister to Sylvioidea was identified as a member of the super family;second, the genus Regulus was united with the Sturnidae and nested in the Muscicapoidea clade instead of being a clade of Passerida.Conclusion: Our results were consistent with Johansson's study of the three superfamilies except for the al ocation of two families, Paridae and Regulidae.
基金This study was funded by the National Natural Science Foundation of China(NSFC,31672292)to DL,NSFC(31770445)to Y.Wu,NSFC(31800338)and the Foundation of Hebei Normal University(L042017B03)to Y.Wang.
文摘Background:Unlike resident birds,migratory birds are generally believed to have evolved to enhance flight efficiency;however,direct evidence is still scarce due to the difficulty of measuring the flight speed and mechanical power.Methods:We studied the differences in morphology,flight kinematics,and energy cost between two passerines with comparable size,a migrant(Fringilla montifringilla,Brambling,BRAM),and a resident(Passer montanus,Eurasian Tree Sparrow,TRSP).Results:The BRAM had longer wings,higher aspect ratio,lower wingbeat frequency,and stroke amplitude compared to the TRSP despite the two species had a comparable body mass.The BRAM had a significantly lower maximum speed,lower power at any specific speed,and thus lower flight energy cost in relative to the TRSP although the two species had a comparable maximum vertical speed and acceleration.Conclusions:Our results suggest that adaptation for migration may have led to reduced power output and maximum speed to increase energy efficiency for migratory flight while residents increase flight speed and speed range adapting to diverse habitats.
基金We thank Yinchao Hao and Wande Li for their assistance with sample collection.This study was funded by the National Natural Science Foundation of China(NSFC,31971413)Natural Science Foundation of Hebei Province(NSFHP,C2020205038)to D.L.Science and Technology Project of Hebei Education Department(QN2019103)to Y.S.
文摘Human commensal species take advantage of anthropogenic conditions that are less likely to be challenged by the selective pressures of natural environments.Their morphological and physiological phenotypes can therefore dissociate from habitat characteristics.Understanding how these species adjust their morphological and physiological traits across latitudinal gradients is fundamental to uncovering the eco-physiological strategies underlying coping mechanisms.Here,we studied morphological traits in breeding Eurasian tree sparrows(ETSs;Passer montanus)among low-latitude(Yunnan and Hunan)and middle-latitude(Hebei)localities in China.We then compared body mass;lengths of bill,tarsometatarsus,wing,total body,and tail feather;and baseline and capture stress-induced levels of plasma corticosterone(CORT)and the metabolites including glucose(Glu),total triglyceride(TG),free fatty acid(FFA),total protein,and uric acid(UA).None of the measured morphological parameters varied with latitude except in the Hunan population,which demonstrated longer bills than those in other populations.Stress-induced CORT levels significantly exceeded baseline levels and decreased with increasing latitude,but total integrated CORT levels did not vary with latitude.Capture stress-induced significantly increased Glu levels and decreased TG levels,independent of site.However,the Hunan population had significantly higher baseline CORT,baseline and stress-induced FFA levels,but lower UA levels,which differed from other populations.Our results suggest that rather than morphological adjustments,physiological adjustments are mainly involved in coping mechanisms for middle-latitude adaptation in ETSs.It is worth investigating whether other avian species also exhibit such dissociation from external morphological designs while depending on physiological adjustments.
文摘On the Qinghai-Tibet Plateau,extreme environmental conditions have imposed intense selective pressure on the evolution of phenotypic traits of wild animals.To date,limited information is available on behavioral and ecological traits concerning niche differentiation among sympatric animals on the Qinghai-Tibet Plateau,especially during winter when the environments are most severe.Here,we studied the seasonal variations in habitat occurrence,territorial behavior,and diet in two sympatric snow finches(the white-rumped snow finch,Onychostruthus taczanowskii,WRSF;and the rufous-necked snow finch,Pyrgilauda ruficollis,RNSF)to determine convergence and divergence of ecological traits in such severe climatic conditions.Our results showed that:(i)WRSF occupied rural areas as a dominant species throughout the annual cycle while RNSF occupied the rural areas in summer and then shifted to human-occupied areas in winter and spring;(ii)WRSFs exhibited robust aggressive behavior and territoriality during winter relative to RNSFs;(iii)the diets of both species varied with the season but did not vary between species except that WRSF ate significantly more seeds but RNSF consumed more starchy material derived from human food waste during winter.Therefore,the separations in the spatial niche and territoriality between WRSF and RNSF,especially in winter,may contribute to alleviating the pressure of interspecific competition,and promoting the coexistence of the two sympatric snow finches in the extreme environments on the Qinghai-Tibet Plateau.
基金This study was supported by National Natural Science Foundation of China(grant no.31772626).
文摘Two consecutive trials were conducted to investigate the effects of glucosinolates(GLS)in rapeseed cake(RSC)on nitrogen(N)metabolism and urine nitrous oxide(N_(2)O)emissions in steers.In trial 1,8 steers and 4 levels of RSC,i.e.0,2.7%,5.4%and 8.0%dry matter(DM)(0,6.0,12.1,18.1 mmol GLS/g DM)were allocated in a replicated 4×4 Latin square.In trial 2,the static incubation technique was used for measuring the N_(2)O emissions of the urine samples collected from trial 1.The results of trial 1 indicated that dietary inclusion of RSC decreased the digested N and increased the fecal N excretion(P<0.01),whereas it did not affect the urinary N excretion,total N excretion and N retention(P>0.10).Dietary inclusion of RSC decreased the urinary excretion of urea while it increased allantoin,total purine derivatives,the predicted rumen microbial N flow and thiocyanate(SCN)(P<0.05).Dietary inclusion of RSC did not affect the plasma triiodothyronine and thyroxine while it down-regulated the plasma relative concentrations of 4-aminohippuric acid,3a,7a-dihydroxycoprostanic acid,phosphatidylserine(14:0/16:0),6b-hydroxyprogesterone,pyrrhoxanthinol,tatridin B,mandelonitrile rutinoside,taraxacoside(P<0.05),and up-regulated hypoglycin B,neuromedin N(1-4),dhurrin,5-deoxykievitone(P<0.01).The results of trial 2 indicated that dietary RSC increased the steer urine N_(2)OeN fluxes,the ratio of N_(2)OeN to N application and the estimated steer urine N_(2)OeN emissions(P<0.01).A close correlation was found between the estimated steer urine N_(2)OeN emissions and the output of urinary SCN(P<0.001).In conclusion,dietary RSC increased the fecal N excretion,whereas it did not affect the urinary N excretion and the N retention rate in steers.Dietary RSC increased rather than decreased the urine N_(2)OeN emissions even though it decreased the urinary excretion of urea.The SCN excreted in urine could be the major factor in increasing the urine N_(2)OeN emissions.Whether other metabolites excreted into urine from RSC have an impact on the urine N_(2)OeN emissions in steers needs to be investigated in the future.
基金This research was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31040304)the Yunnan Provincial Department of Science and Technology(202103AC100001+2 种基金202001BB050078)the National Natural Science Foundation of China(32061143014)E.J.was supported by the T€ubitak Outstanding Researchers Program,BIDEB 2232(118C250).
文摘Rivers and their lakes are among the world’smost important ecosystems supporting high biodiversity and providing various services through connections with vast landscapes.Reconciling exploitation with sustainability remains one of the world’s greatest challenges tomaintain and/or recover the health of river ecosystems and hence their biodiversity and ecosystem services.1 As one of the major national initiatives toward building“ecological civilization”and an extensive protection of the Yangtze River in China,a“10-year fishing ban”plan(TYFB)was launched from January 2021.
基金supported by the Key Program of the National Key Research and Development Program of China(nos.2017YFA0106100,2016YFY1101303)the National Natural Science Funds for Outstanding Young Scholar(no.81622027)+2 种基金the Key Program of National Natural Science Foundation of China(no.31830030)the Beijing NOVA Program of China(no.2016B615)Joint funds for National Natural Science Foundation of China(no.U1601221).
文摘The cell-derived extracellular matrix(ECM)-modified scaffolds have advantages of mimic tissue specificity and been thought to better mimic the native cellular microenvironment in vitro.ECM derived from cardiac fibroblasts(CFs)are considered as key elements that provide a natural cell growth microenvironment and change the fate of cardiomyocytes(CMs).Here,a new hybrid scaffold is designed based on silk fibroin(SF)scaffold and CFs-derived ECM.CFs were seeded on the SF scaffold for 10days culturing and decellularized to produce CFs-derived ECM-coated SF scaffold.The results showed that the cell-derived ECM-modified silk fibroin scaffold material contained collagen,laminin,fibronectin and other ECM components with myocardial-like properties.Further to explore its effects on brown adipose stem cells(BASCs)differentiation into CMs.We found that the CFderived ECM-coated scaffold also increased the expression of CM-specific proteins(e.g.cardiac troponin T and α-actinin)of BASCs.Notably,the b1-integrin-dependent transforming growth factor-β1 signaling pathway was also involved in the regulation of CF-derived ECM by promoting the differentiation of BASCs into CMs.Overall,these findings provide insights into the bionic manufacturing of engineered cardiac tissues(ECTs)and establish a theoretical basis for the construction of ECTs.
