为探究急性温度胁迫对红耳龟Trachemys scripta elegans消化和免疫功能的影响及饲料添加维生素E(VE)的干预效应。选取健康2龄红耳龟112只,分成未添加VE组和添加VE组(250 mg·kg^(−1)),每组设室温(30℃)、低温(17℃)和高温(35℃),于...为探究急性温度胁迫对红耳龟Trachemys scripta elegans消化和免疫功能的影响及饲料添加维生素E(VE)的干预效应。选取健康2龄红耳龟112只,分成未添加VE组和添加VE组(250 mg·kg^(−1)),每组设室温(30℃)、低温(17℃)和高温(35℃),于胁迫0 h、6 h、12 h取血液和肠道组织,检测血清抗氧化酶和肠道消化酶活性。结果表明,未添加VE组低温下淀粉酶和脂肪酶的活性显著上升,谷胱甘肽(GSH)含量显著降低,高温下胃蛋白酶活性极显著升高,超氧化物歧化酶(SOD)活性显著升高,GSH含量显著下降;添加VE组急性温度胁迫下的SOD活性升幅减小,GSH含量升高,低温下胃蛋白酶活性显著提高,脂肪酶活性显著降低;高温下胃蛋白酶活性极显著降低,淀粉酶活性显著升高。本研究初步阐释了急性温度胁迫对红耳龟的损伤机制,同时发现饲料添加VE具有一定程度的缓解作用,为生产中应对急性温度应激探索了一条绿色可行途径。展开更多
In 1998,a study on forty-five four-eyed turtles(Sacalia quadriocellata) was initiated to gather preliminary biological data of this species and to investigate the feasibility of its captive reproduction.In the followi...In 1998,a study on forty-five four-eyed turtles(Sacalia quadriocellata) was initiated to gather preliminary biological data of this species and to investigate the feasibility of its captive reproduction.In the following six years,no courtship behavior was found occurring in males and no oviposition in females.From 2004 to 2007,two successful techniques were applied to initiate reproductive behavior:1) injecting exogenous reproductive hormones;and 2) reducing the stress of living in captivity.As a result of the hormone treatments,courtship behavior and copulation were observed during September and October,2005.However,no courtship displays were seen from the CK males,which were not treated with hormones.Ovulation occurred between December and March,and the correlation was not significant between behavior of ovulation and food intake.Females laid only one clutch of eggs each year,with 2.47 eggs(n=34,range=1–4) at average,and 84 eggs were totally obtained,of which 13 were damaged,52 were infertile and 19 fertile.Of the fertile eggs,nine were hatched with mean incubation period of 105.9 days(n=9,range=89–122 days) at temperature ranging from 24 to 27℃.展开更多
Luteinizing hormone-releasing hormone(LHRH) is known to influence sexual behavior in many vertebrate taxa,but there have been no systematic studies on the role of LHRH in sexual behavior of turtles.We tested the hypot...Luteinizing hormone-releasing hormone(LHRH) is known to influence sexual behavior in many vertebrate taxa,but there have been no systematic studies on the role of LHRH in sexual behavior of turtles.We tested the hypotheses that exogenous LHRH analogues would induce sexual behavior of male Four-eyed turtle,Sacalia quadriocellata.We examined this by challenging males with intramuscular injections of mammalian luteinizing hormone-releasing hormone analogue(LHRH-A),human chorionic gonadotropin(HCG),or a combination of the two,and subsequently exposing them to sexually receptive females for behavioral observation.Our data show that the injection of only HCG could not,while that of only LHRH-A could,facilitate sexual behavior along with testicular recrudescence and spermatogenesis in S.quadriocellata.The injection of both LHRH-A and HCG would induce more drastic sexual behavior of the animals than that of LHRH-A alone,indicating HCG enhances the effects of LHRH-A induced sexual behavior.However,different pharmacological dosages of LHRH-A(0.5 g,1 g,2 g per 100 g bodyweight) did not correspond to different activity levels.Though the mechanism of LHRH effect was not determined,this study may support that the sexual behavior of S.quadriocellata which occurs at the beginning of the injection despite regression of the gonads.This is the first report on the exogenous LHRH-A induced sexual behavior for this species.展开更多
In this paper, an integrated system of solid oxide fuel cell(SOFC) and methane steam reforming for hydrogen production is proposed. The mathematical model of the coupled integrated system is studied by COMSOL and Aspe...In this paper, an integrated system of solid oxide fuel cell(SOFC) and methane steam reforming for hydrogen production is proposed. The mathematical model of the coupled integrated system is studied by COMSOL and Aspen software, and the energy analysis of the integrated system is carried out. The system recovers and reuses the waste heat of the SOFC stack through the heat exchanger, which can realize the cascade efficient use of energy. By adjusting the different reforming temperatures, steam-to-carbon ratio and SOFC operating temperature of methane steam reforming to produce hydrogen, the parameters that have a greater impact on the system are studied. The research results show that as the steam-to-carbon ratio and reformer operating temperature increase, the net output power and efficiency of the system increase. When the fuel cell operating temperature is 800℃, the output power and efficiency of the system reach the maximum values of 899.93 W and 52.52%, respectively. Increasing the operating temperature of SOFC helps to improve the efficiency of fuel cells, but the efficiency of the integrated system of methane steam reforming hydrogen production and SOFC first increases and then decreases. This system can realize the direct coupling between the SOFC reactor subsystem and the methane steam reforming hydrogen production system under optimized conditions, which has reference significance for the actual operating conditions of the coupled system.展开更多
基金supported by the National Natural Science Foundation of China(30910103916)the Key Project of Science and Technology Program of Hainan,China(06122)
文摘In 1998,a study on forty-five four-eyed turtles(Sacalia quadriocellata) was initiated to gather preliminary biological data of this species and to investigate the feasibility of its captive reproduction.In the following six years,no courtship behavior was found occurring in males and no oviposition in females.From 2004 to 2007,two successful techniques were applied to initiate reproductive behavior:1) injecting exogenous reproductive hormones;and 2) reducing the stress of living in captivity.As a result of the hormone treatments,courtship behavior and copulation were observed during September and October,2005.However,no courtship displays were seen from the CK males,which were not treated with hormones.Ovulation occurred between December and March,and the correlation was not significant between behavior of ovulation and food intake.Females laid only one clutch of eggs each year,with 2.47 eggs(n=34,range=1–4) at average,and 84 eggs were totally obtained,of which 13 were damaged,52 were infertile and 19 fertile.Of the fertile eggs,nine were hatched with mean incubation period of 105.9 days(n=9,range=89–122 days) at temperature ranging from 24 to 27℃.
基金supported by the National Natural Science Foundation of China(30910103916)the Key Project of the Science and Technology Program of Hainan,China(06122)
文摘Luteinizing hormone-releasing hormone(LHRH) is known to influence sexual behavior in many vertebrate taxa,but there have been no systematic studies on the role of LHRH in sexual behavior of turtles.We tested the hypotheses that exogenous LHRH analogues would induce sexual behavior of male Four-eyed turtle,Sacalia quadriocellata.We examined this by challenging males with intramuscular injections of mammalian luteinizing hormone-releasing hormone analogue(LHRH-A),human chorionic gonadotropin(HCG),or a combination of the two,and subsequently exposing them to sexually receptive females for behavioral observation.Our data show that the injection of only HCG could not,while that of only LHRH-A could,facilitate sexual behavior along with testicular recrudescence and spermatogenesis in S.quadriocellata.The injection of both LHRH-A and HCG would induce more drastic sexual behavior of the animals than that of LHRH-A alone,indicating HCG enhances the effects of LHRH-A induced sexual behavior.However,different pharmacological dosages of LHRH-A(0.5 g,1 g,2 g per 100 g bodyweight) did not correspond to different activity levels.Though the mechanism of LHRH effect was not determined,this study may support that the sexual behavior of S.quadriocellata which occurs at the beginning of the injection despite regression of the gonads.This is the first report on the exogenous LHRH-A induced sexual behavior for this species.
基金supported by the National Natural Science Foundation of China(Grant No.51866001)Initial Research Funds for the Hainan Universities(KYQD(ZR)1841)。
文摘In this paper, an integrated system of solid oxide fuel cell(SOFC) and methane steam reforming for hydrogen production is proposed. The mathematical model of the coupled integrated system is studied by COMSOL and Aspen software, and the energy analysis of the integrated system is carried out. The system recovers and reuses the waste heat of the SOFC stack through the heat exchanger, which can realize the cascade efficient use of energy. By adjusting the different reforming temperatures, steam-to-carbon ratio and SOFC operating temperature of methane steam reforming to produce hydrogen, the parameters that have a greater impact on the system are studied. The research results show that as the steam-to-carbon ratio and reformer operating temperature increase, the net output power and efficiency of the system increase. When the fuel cell operating temperature is 800℃, the output power and efficiency of the system reach the maximum values of 899.93 W and 52.52%, respectively. Increasing the operating temperature of SOFC helps to improve the efficiency of fuel cells, but the efficiency of the integrated system of methane steam reforming hydrogen production and SOFC first increases and then decreases. This system can realize the direct coupling between the SOFC reactor subsystem and the methane steam reforming hydrogen production system under optimized conditions, which has reference significance for the actual operating conditions of the coupled system.
