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The Seasonal Acclimatisation of Locomotion in a Terrestrial Reptile, Plestiodon chinensis(Scincidae) 被引量:4
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作者 baojun sun Wenqi Tang +1 位作者 Zhigao Zeng Weiguo Du 《Asian Herpetological Research》 SCIE 2014年第3期197-203,共7页
Studies of the seasonal acclimatisation of behavioural and physiological processes usually focus on aquatic or semi-aquatic ectotherms and focus less effort on terrestrial ectotherms that experience more thermally het... Studies of the seasonal acclimatisation of behavioural and physiological processes usually focus on aquatic or semi-aquatic ectotherms and focus less effort on terrestrial ectotherms that experience more thermally heterogeneous environments. We conducted comparative studies and thermal acclimation experiments on the locomotion of the Chinese skink (Plestiodon chinensis) to test whether seasonal acclimatisation in locomotion exists in these terrestrial ectothermic vertebrates, and whether seasonal acclimatisation is predominantly induced by thermal environments. In natural populations, skinks ran faster during the summer season than during the spring season at high-test temperatures ranging from 27℃ to 36℃ but not at low-test temperatures ranging from 18℃ to 24℃. In contrast, the thermal acclimation experiments showed that the cold-acclimated skinks ran faster than the warm-acclimated skinks at the low- test temperatures but not at high-test temperatures. Therefore, the seasonal acclimatisation occurs to P chinensis, and may be induced by temperature as well as other factors like food availability, as indicated by the seasonal variation in the thermal dependence of locomotion, and the discrepancy between seasonal acclimatisation and thermal acclimation on locomotion. 展开更多
关键词 LIZARD temperature terrestrial ectotherms thermal acclimation
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Thermal-physiological Strategies Underlying the Sympatric Occurrence of Three Desert Lizard Species 被引量:1
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作者 Xueqing WANG Shuran LI +4 位作者 Li LI Fushun ZHANG Xingzhi HAN Junhuai BI baojun sun 《Asian Herpetological Research》 SCIE CSCD 2019年第3期190-196,共7页
Sympatric reptiles are the ideal system for investigating temperature-driven coexistence. Understanding thermally physiological responses of sympatric lizards is necessary to reveal the physiological mechanisms that u... Sympatric reptiles are the ideal system for investigating temperature-driven coexistence. Understanding thermally physiological responses of sympatric lizards is necessary to reveal the physiological mechanisms that underpin the sympatric occurrence of reptiles. In this study, we used three lizard species, Eremias argus, E. multiocellata, and Phrynocephalus przewalskii, which are sympatric in the Inner Mongolia desert steppe, as a study system. By comparing their resting metabolic rates(RMR) and locomotion at different body temperatures, we aimed to better understand their physiological responses to thermal environments, which may explain the sympatric occurrence of these lizards. Our results showed that E. argus had significantly higher RMR and sprint speed than E. multiocellata, and higher RMR than P. przewalskii. In addition, the optimal temperature that maximized metabolic rates and locomotion for E. argus and E. multiocellata was 36°C, whereas for P. przewalskii it was 39°C. Our study revealed the physiological responses to temperatures that justify the sympatric occurrence of these lizards with different thermal and microhabitat preferences and active body temperatures. Eremias argus and E. multiocellata, which have lower body temperatures than P. przewalskii, depend on higher RMR and locomotion to compensate for their lower body temperatures in field conditions. Our study also highlights the importance of using an integrative approach, combining behavior and physiology, to explore the basis of sympatric occurrence in ectothermic species. 展开更多
关键词 SYMPATRIC LIZARDS resting metabolic rate locomotion EREMIAS ARGUS E.multiocellata Phrynocephalus PRZEWALSKII
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Elevational Variation in Reproductive Strategy of a Widespread Lizard:High-Elevation Females Lay Fewer but Larger Eggs 被引量:1
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作者 Gideon Gywa DEME Xin HAO +2 位作者 Liang MA baojun sun Weiguo DU 《Asian Herpetological Research》 SCIE CSCD 2022年第3期198-204,共7页
Identifying how reproductive strategies such as the trade-off between clutch size versus egg mass vary with elevational gradients is essential for our understanding of life-history evolution.We studied lacertid lizard... Identifying how reproductive strategies such as the trade-off between clutch size versus egg mass vary with elevational gradients is essential for our understanding of life-history evolution.We studied lacertid lizards(Eremias argus)in China,from six populations at different altitudes,to assess elevational variation in reproductive strategy.We found significant between-population variation in maternal body size and clutch mass,but these variations were not explained by elevational differences.However,high-elevation females tended to produce smaller clutches of larger eggs compared with their low-elevation counterparts,demonstrating an elevational change in the trade-off between egg size and number.The egg size-number trade-off is a reproductive strategy that may favor large offspring,better enabling them to survive severe and unpredictable environments found at high elevations. 展开更多
关键词 between-population variation clutch size egg size elevational gradient Eremiasargus local adaptation reproductive output
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Thermal Biology of Cold-climate Distributed Heilongjiang Grass Lizard,Takydromus amurensis
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作者 Xin HAO Shiang TAO +6 位作者 Yu MENG Jingyang LIU Luoxin CUI Wanli LIU baojun sun Peng LIU Wenge ZHAO 《Asian Herpetological Research》 SCIE CSCD 2020年第4期350-359,共10页
Thermal biology traits reflect thermal adaptations to an environment and can be used to infer responses to climate warming in animal species.Within a widespread genus or species,assessing the latitudinal or altitudina... Thermal biology traits reflect thermal adaptations to an environment and can be used to infer responses to climate warming in animal species.Within a widespread genus or species,assessing the latitudinal or altitudinal gradient of thermal physiological traits is essential to reveal thermal adaptations and determine future vulnerability to climate warming geographically.We determined the thermal biology traits of a cold-climate distributed lizard,Takydromus amurensis,and integrated published thermal biology traits within the genus Takydromus to reveal a preliminary geographical pattern in thermal adaptation.The mean selected body temperature(cloaca temperature;T_(sel)),critical thermal maximum(CT_(max)),critical thermal minimum(CT_(min)),and optimal temperature for locomotion(i.e.,sprint speed;T_(opt)) of T.amurensis were 32.6,45.1,3.1,and 33.4℃,respectively.The resting metabolic rates of T.amurensis were po sitively related to temperature from 18℃ to 38℃.We compared the traits of tropical T.sexlineatus,subtropical T.septentrionalis,and T.wolteri with T.amurensis and found that the CT_(max) and thermal tolerance range(the difference between CT_(max) and CT_(min);TTR) increased toward high latitudes,whereas CT_(min) increased toward low latitudes in these four Takydromus lizards.According to this preliminary pattern,we speculate the species at medium and low latitudes would be more vulnerable to extreme heat events caused by ongoing climate warming.We highlight the importance of integrating thermal biology traits along geographical clues,and its potential contribution to evaluate the vulnerabilities of species in the context of climate warming. 展开更多
关键词 counter gradient CT_(max) CT_(min) thermal biological trait thermal tolerance range T_(sel) Takydromus
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Does Light Exposure during Embryonic Development Affect Cognitive Behavior in a Lizard?
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作者 Xinghan LI Chenxu WANG +4 位作者 Guoshuai TANG Shuran LI Liang MA baojun sun Yongpu ZHANG 《Asian Herpetological Research》 SCIE CSCD 2020年第1期56-62,共7页
Light is essential for embryonic development in many ovipa rous animals including fish,amphibians,and birds.However,light may be harmful for reptile embryos developing underground where they are in complete darkness a... Light is essential for embryonic development in many ovipa rous animals including fish,amphibians,and birds.However,light may be harmful for reptile embryos developing underground where they are in complete darkness and beneath thin eggshells.Nonetheless,how embryonic light conditions affect reptile development and offspring remains largely unknown.Here we incubated eggs in dark and light conditions to determine the effects of light exposure on embryonic development and offspring visual ability,spa tial cognitive ability and growth in a lacertid lizard,Eremias argus.Our experiments demonstrated that light stimulation shortened incubation duration of eggs,but did not affect hatching success,offspring size,visual ability or survival More interestingly,light exposure during incuba tion decreased spa tial cognitive ability and post-hatching growth of offspring On the basis of nega tive effects on offspring growth rates,our study indicates that in squamate reptiles with thin eggshells,light exposure in early development has negative effects on offspring cognitive ability. 展开更多
关键词 EMBRYONIC development light vision COGNITIVE ability EREMIAS ARGUS
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Clinical Analysis of Hospital-acquired Bloodstream Infection in the Elderly
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作者 baojun sun 《Journal of Geriatric Medicine》 2019年第1期8-14,共7页
Objective: This study was designed to get epidemiological characteristics, etiology characteristics, prognosis assessment and prognostic factors of hospital-acquired bloodstream infection (HABSI) in the elderly in Chi... Objective: This study was designed to get epidemiological characteristics, etiology characteristics, prognosis assessment and prognostic factors of hospital-acquired bloodstream infection (HABSI) in the elderly in Chinese PLA General Hospital and aimed at providing a reference for HABSI in the elderly on clinical diagnosis and treatment to improve the prognosis. Methods: The clinical data and pathology data of 210 cases of the elderly patients with HABSI from 2009 to 2012 in geriatric wards were retrospectively analyzed. Compare the clinical assessment effects of APACHE-II score, SAPS-II score and SOFA score to HABSI prognosis in the elderly by plotting the receiver operating characteristic curve. Use univariate and multivariate logistic regression analysis to get prognostic factors of HABSI in the elderly. Results: Univariate analysis of mortality: Day 1 apache -> 18 II score, lung infection, invasive ventilation, chronic hepatic insufficiency, chronic renal insufficiency, substantive organ malignant tumor, deep venipuncture, indwelling gastric tube indwelling ureter, complicated with shock and acquired bloodstream infections in the elderly patients with 7 days survival state association is significant. Day- 1 SOFA score>7, chronic liver dysfunction, chronic renal insufficiency, concurrent shock, hemodialysis and 28-day survival status of patients with acquired bloodstream infection in elderly hospitals were significantly associated. Multivariate unconditioned logistic regression analysis related to death: Day-1APACHE-II score>18, parenchymal malignant tumors, and concurrent shock are independent risk factors for 7-day death in elderly patients with acquired bloodstream infection. Day-1 SOFA score>7, chronic renal insufficiency, and concurrent shock are independent risk factors for 28-day mortality in elderly patients with acquired bloodstream infection. Conclusion: The incidence of acquired bloodstream infections in the elderly was 1.37%. The 7-day and 28-day mortality rates were 8.10% and 22.38%, respectively. Concurrent shock is 26.7%. The 28- day mortality rate of concurrent shock patients was 48.21%. The best outcome score for the 7-day prognosis of elderly patients with acquired bloodstream infection was the Day-1APACHE-II score, followed by the Day-1 SOFA score. The best score for the 28-day prognostic assessment was the Day-1 SOFA score. 展开更多
关键词 ELDERLY HOSPITAL-ACQUIRED BLOODSTREAM infection ETIOLOGY PROGNOSIS
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Optimizing protected areas to boost the conservation of key protected wildlife in China 被引量:1
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作者 Chunrong Mi Kai Song +5 位作者 Liang Ma Jiliang Xu baojun sun Yuehua sun Jianguo Liu Weiguo Du 《The Innovation》 EI 2023年第3期55-62,共8页
To meet the challenge of biodiversity loss and reach the targets of the proposed Post-2020 Global Biodiversity Framework,the Chinese government updated the list of national key protected wildlife in 2021 and has been ... To meet the challenge of biodiversity loss and reach the targets of the proposed Post-2020 Global Biodiversity Framework,the Chinese government updated the list of national key protected wildlife in 2021 and has been continually expanding the protected areas(PAs).However,the status of protected wildlife in PAs remains unclear.In this study,we conducted a national assessment of the status of protected wildlife and suggested an optimization plan to overcome these shortcomings.From 1988 to 2021,the number of protected species almost doubled,and the area of PAs increased by 2.4 times,covering over 92.8%of the protected species.Nonetheless,some protected species have less than 10%of their habitat included in PAs.Despite the significant addition of amphibians and reptiles to the latest protection list,they are the fewest species and are the least covered by PAs compared with birds and mammals.To fix these gaps,we systematically optimized the current PAs network by adding another 10.0%of China’s land area as PAs,which resulted in 37.6%coverage of protected species’habitats in PAs.In addition,26 priority areas were identified.Our research aimed to identify gaps in current conservation policies and suggest optimization solutions to facilitate wildlife conservation planning in China.In general,updating the list of key protected wildlife species and systematically optimizing PA networks are essential and applicable to other countries facing biodiversity loss. 展开更多
关键词 protected HABITAT OPTIMIZATION
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Phenotypic consequences of maternally selected nests:a cross-fostering experiment in a desert lizard 被引量:1
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作者 Shuran LI Xin HAO +3 位作者 baojun sun Junhuai BI Yongpu ZHANG Weiguo DU 《Integrative Zoology》 SCIE CSCD 2021年第5期741-754,共14页
Despite the importance of maternally selected nests in shaping offspring phenotypes,our understanding of how the nest environment affects embryonic development and offspring traits of most non-avian reptiles is rather... Despite the importance of maternally selected nests in shaping offspring phenotypes,our understanding of how the nest environment affects embryonic development and offspring traits of most non-avian reptiles is rather limited largely due to the logistical difficulty in locating their nests.To identify the relative contributions of environmental(temporal[seasonal]and spatial[nest-site])and intrinsic(clutch)factors on embryonic development and offspring traits,we conducted a cross-fostering experiment by swapping eggs between maternally-selected nests of the toad-headed agama(Phrynocephalus przewalskii)in the field.We found that nest environment explained a large proportion of variation in incubation duration,hatching success,and offspring size and growth.In contrast,clutch only explained a small proportion of variation in these embryonic and offspring traits.More significantly,compared with spatial effects,seasonal effects explained more phenotypic variation in both embryonic development and offspring traits.Eggs laid early in the nesting season had longer incubation durations and produced smaller hatchlings with higher post-hatching growth rates than did later-laid eggs.Consequently,hatchlings from early-laid eggs reached larger body sizes prior to winter.In addition,we found that female toad-headed agama did not select nests specific to reaction norms of their own offspring because hatchlings from original or translocated nests had similar phenotypic traits.Overall,our study demonstrates the importance of seasonal variation in nest environments in determining embryonic development and offspring phenotypes,which has not been widely appreciated at least in non-avian reptiles. 展开更多
关键词 embryonic development HATCHLING maternal effect nest selection nest temperature REPTILE
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Embryonic and post-embryonic responses to high-elevation hypoxia in a low-elevation lizard
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作者 Xinghan LI Pengfei WU +3 位作者 Liang MA Christopher HUEBNER baojun sun Shuran LI 《Integrative Zoology》 SCIE CSCD 2020年第4期338-348,共11页
Low-elevation species can migrate toward higher elevations to survive in a warming world.However,animals’responses to hypoxia when migrating to high elevations have rarely been addressed.To identify the response of l... Low-elevation species can migrate toward higher elevations to survive in a warming world.However,animals’responses to hypoxia when migrating to high elevations have rarely been addressed.To identify the response of lowelevation lizards to high-elevation hypoxia,we collected field body temperatures(Tfb)and operative temperatures(Te)of lizards(Eremias argus)from a low-elevation population(1036 m)and a high-elevation population(2036 m),and then determined adult thermal physiology,embryonic development,and hatchling phenotypes after acclimating low-elevation lizards and incubating their eggs in conditions mimicking the low-elevation oxygen condition(18.5%O2)and high-elevation oxygen(hypoxic)condition(16.5%O2).Our study revealed that Tfb and Te were higher for the low-elevation population compared to the high-elevation population.We also found adults from low elevation acclimated to hypoxia preferred lower body temperatures,but did not show changes in locomotor performance or growth.In addition,hypoxia did not affect embryonic development(hatching time and success)or hatchling phenotypes(body size and locomotor performance).These results suggest that adult lizards from low elevations can respond to hypoxia-induced stress when migrating to high elevations by behaviorally thermoregulating to lower body temperatures in order to sustain normal functions.Similarly,low-elevation embryos can develop normally(with unchanged hatching success and offspring phenotypes)under the high-elevation hypoxic condition.This study highlights that low-elevation populations of a species that inhabits a range of elevations can buffer the impact of high-elevation hypoxic conditions to some degree and thus attain similar fitness to the source population. 展开更多
关键词 climate warming high elevation HYPOXIA oviparous lizard thermal preference
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