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1.
汤章城 《生命科学》2002,14(6):375-378
由于空间生物技术潜在重大社会和经济效益。加强探索空间生物技术的发展。目前已经成为空间科学技术发展的重点之一。我国的空间技术在系列应用卫星成功发展的基础上,已将进入到更先进的载人飞船阶段。我国的科技人员将会有更多的机会,更好的条件在空间开展生物技术的研究。以促进其发展和应用,造福于人类,本文简要地介绍了空间发展生物技术的优越性。空间生物技术发展的热点和趋势,以及空间生物技术硬件发展的动态。  相似文献   

2.
Knowledge of the effects of thermal conditions on animal movement and dispersal is necessary for a mechanistic understanding of the consequences of climate change and habitat fragmentation. In particular, the flight of ectothermic insects such as small butterflies is greatly influenced by ambient temperature. Here, variation in body temperature during flight is investigated in an ecological model species, the Glanville fritillary butterfly (Melitaea cinxia). Attention is paid on the effects of flight metabolism, genotypes at candidate loci, and environmental conditions. Measurements were made under a natural range of conditions using infrared thermal imaging. Heating of flight muscles by flight metabolism has been presumed to be negligible in small butterflies. However, the results demonstrate that Glanville fritillary males with high flight metabolic rate maintain elevated body temperature better during flight than males with a low rate of flight metabolism. This effect is likely to have a significant influence on the dispersal performance and fitness of butterflies and demonstrates the possible importance of intraspecific physiological variation on dispersal in other similar ectothermic insects. The results also suggest that individuals having an advantage in low ambient temperatures can be susceptible to overheating at high temperatures. Further, tolerance of high temperatures may be important for flight performance, as indicated by an association of heat‐shock protein (Hsp70) genotype with flight metabolic rate and body temperature at takeoff. The dynamics of body temperature at flight and factors affecting it also differed significantly between female and male butterflies, indicating that thermal dynamics are governed by different mechanisms in the two sexes. This study contributes to knowledge about factors affecting intraspecific variation in dispersal‐related thermal performance in butterflies and other insects. Such information is needed for predictive models of the evolution of dispersal in the face of habitat fragmentation and climate change.  相似文献   

3.
Space flight experiments have suggested that microgravity can affect cellular processes in microorganisms. To simulate the microgravity environment on earth, several models have been developed and applied to examine the effect of microgravity on secondary metabolism. In this paper, studies of effects of space flight on secondary metabolism are exemplified and reviewed along with the advantages and disadvantages of the current models used for simulating microgravity. This discussion is both signi?cant and timely to researchers considering the use of simulated microgravity or space flight to explore effects of weightlessness on secondary metabolism.  相似文献   

4.
The temperate‐zone butterfly Pararge aegeria can use three developmental pathways corresponding to different seasonal cohorts: (1) development with a pupal winter diapause resulting in early spring adults; (2) development with a larval winter diapause resulting in late‐spring adults and (3) direct development resulting in summer or second generation adults. In order to test adaptive predictions, we compared variation in flight‐ and thermoregulation‐related morphology among adult males and females from the three pathways using both field data (i.e. wild‐caught butterflies) and experimental breeding data (i.e. reared under different photoperiod regimes). Morphological patterns among the pathways were largely similar in the field and rearing data. Seasonal patterns differed between the sexes for most traits, including (relative) size measures and wing colour. Our results suggest sex‐related, adaptive seasonal plasticity for morphological traits related to flight behaviour in a multivoltine insect.  相似文献   

5.
Abstract. Body temperatures and kinematics are measured for male Centris pallida bees engaged in a variety of flight behaviours (hovering, patrolling, pursuit) at a nest aggregation site in the Sonoran Desert. The aim of the study is to test for evidence of thermoregulatory variation in convective heat loss and metabolic heat production and to assess the mechanisms of acceleration and forward flight in field conditions. Patrolling males have slightly (1–3 °C) cooler body temperatures than hoverers, despite similar wingbeat frequencies and larger body masses, suggesting that convective heat loss is likely to be greater during patrolling flight than during hovering. Comparisons of thorax and head temperature as a function of air temperature (Ta) indicate that C. pallida males are thermoregulating the head by increasing heat transfer from the thorax to the head at cool Ta. During patrolling flight and hovering, wingbeat frequency significantly decreases as Ta increases, indicating that variation in metabolic heat production contributes to thermal stability during these behaviours, as has been previously demonstrated for this species during flight in a metabolic chamber. However, wingbeat frequency during brief (1–2 s) pursuits is significantly higher than during other flight behaviours and independent of Ta. Unlike most other hovering insects, C. pallida males hover with extremely inclined stroke plane angles and nearly horizontal body angles, suggesting that its ability to vary flight speed depends on changes in wingbeat frequency and other kinematic mechanisms that are not yet described.  相似文献   

6.
The effect of the thermal environment on sleep quality has attracted considerable attention, as sleep forms one-third of human lifetime and the occupied space is largely constrained during sleep. With an increasing development of partial space regulation and task air conditioning systems and devices, thermal comfort demand concerning local thermal conditions has attracted more and more attention. In the present study, experiment was conducted and data mining technologies were performed to investigate correlations between local thermal conditions and whole body thermal comfort in sleeping state. The identification of local thermal condition included two steps: the first step was to clarify thermal sensation links between local and covered body, and the second step was to identify local thermal sensation inclination towards different thermal comfort levels. Thermal sensation correlations among local body parts and covered body were obtained. Back, face, and thigh were identified as three dominant linear-correlated local parts with weighting factors 0.488, 0.388, and 0.152, respectively; in addition, chest, arm, leg and foot were found as non-negligible local parts in the estimation of covered body thermal sensation. By dividing the sleeping human body into three parts as head, trunk and extremity, the proper local thermal sensations and their coupling relationships for whole body sleeping thermal comfort have been elaborated by three rules. The present study provides implications in sleeping thermal environment regulation in neutral to cold indoor conditions.  相似文献   

7.
Licorice (Glycyrrhiza uralensis Fisch.) seeds were flown on a recoverable satellite for 18 days(the average radiation dose in the flight recovery module was 0.102 mGy/d, the distance from flight apogee to earth was 350 km, gravity 10-6). After returning to earth, the seeds were germinated and grown to maturity. The parallel ground-based seeds were also planted under the same conditions. The leaves of licorice were used for inter-simple sequence repeat (ISSR) analysis and the two main secondary metabolites in one-year-old roots were analyzed by high performance liquid chromatography (HPLC). Among 22 random primers used in this experiment, 6 primers generated different DNA band types. Analysis of HPLC showed that the content of glycyrrhizic acid (GA) and liquiritin (LQ) in the roots from seeds flown in space was respectively 2.19, 1.18 times higher than that of the control group. The results demonstrated that the extraterrestrial environment induced mutagenic effects on licorice and affected its secondary metabolites. These changes indicated that extraterrestrial orbit is possible means of breeding of licorice so as to preserve this endangered medicinal plant.  相似文献   

8.
汪静  程江  曹墨菊 《广西植物》2016,36(6):707-712
为了解太空诱变玉米核不育突变体矮化的遗传规律和原因,该研究以不育突变体为母本,自交系178、478为父本,对测交 F1、F2群体进行育性鉴定和株高分析,对 F2可育株进行基因型和株高分析,对姊妹交后代分离群体进行育性鉴定和株高、雄穗长度、节间数、节间长度分析,同时,还对姊妹交后代分离群体进行施赤霉素处理,调查育性和株高的变化。结果表明:178和478背景下的 F1表现出与测交母本一样的极显著差异;在178和478核背景下的 F2中,不育株株高极显著矮于可育株,两核背景下的不育株间株高差异不显著,而可育株间株高差异极显著;F2中纯合和杂合可育株的株高差异不显著;姊妹交后代分离群体中不育株株高、雄穗长度、节间数和节间长度极显著小于可育株;外施赤霉素的不育株在苗期表现出对赤霉素一定的敏感性,但株高最终未恢复正常高度。因此,得出该突变体矮化表现稳定,与不育性状并存,且不受细胞核背景的影响;核不育基因对植株株高的矮化无剂量效应;突变体的矮化与雄穗长度、节间数和节间长度有关;突变体不完全属于赤霉素不敏感型,其矮化并不是单一缺乏赤霉素而引起。该研究结果为认识太空诱变玉米核不育突变体矮化的遗传和生理机制提供了参考。  相似文献   

9.
A thermal comfort field study has been carried out in five cities in the humid subtropical climate zone in China. The survey was performed in naturally ventilated and air-conditioned buildings during the summer season in 2006. There were 229 occupants from 111 buildings who participated in this study and 229 questionnaire responses were collected. Thermal acceptability assessment reveals that the indoor environment in naturally ventilated buildings could not meet the 80% acceptability criteria prescribed by ASHRAE Standard 55, and people tended to feel more comfortable in air-conditioned buildings with the air-conditioned occupants voting with higher acceptability (89%) than the naturally ventilated occupants (58%). The neutral temperatures in naturally ventilated and air-conditioned buildings were 28.3°C and 27.7°C, respectively. The range of accepted temperature in naturally ventilated buildings (25.0∼31.6°C) was wider than that in air-conditioned buildings (25.1∼30.3°C), which suggests that occupants in naturally ventilated buildings seemed to be more tolerant of higher temperatures. Preferred temperatures were 27.9°C and 27.3°C in naturally ventilated and air-conditioned buildings, respectively, both of which were 0.4°C cooler than neutral temperatures. This result suggests that people of hot climates may use words like “slightly cool” to describe their preferred thermal state. The relationship between draught sensation and indoor air velocity at different temperature ranges indicates that indoor air velocity had a significant influence over the occupants’ comfort sensation, and air velocities required by occupants increased with the increasing of operative temperatures. Thus, an effective way of natural ventilation which can create the preferred higher air movement is called for. Finally, the indoor set-point temperature of 26°C or even higher in air-conditioned buildings was confirmed as making people comfortable, which supports the regulation in China that in public and office buildings the set-point temperature of air-conditioning system should not be lower than 26°C.  相似文献   

10.
11.
Abstract.  According to biophysical principles, colour and size are important phenotypic factors that may influence body temperature and activity in ectothermic insects. In taxa showing female-limited polymorphism, males and female morphs differ in body colour, size and activity pattern. However, no previous study has evaluated whether such phenotypic and behavioural variation relates to differences between males and female morphs in thermal properties. In the present study, the relationships between body colour, size, activity and body temperature are examined under laboratory and field conditions, for the polymorphic damselfly Enallagma cyathigerum (Charpentier, 1840) (Odonata: Zygoptera). Contrary to expectation, males and female colour morphs of this species do not differ in thermal properties (i.e. heating characteristics or field body temperatures). When questioning phenotype and activity, temperature does not appear to be relevant for understanding the maintenance of female-limited polymorphism.  相似文献   

12.
基于CFD的城市绿地空间格局热环境效应分析   总被引:1,自引:0,他引:1  
刘艳红  郭晋平  魏清顺 《生态学报》2012,32(6):1951-1959
运用CFD数值模拟方法,结合RS技术,对城市中五类常见的绿地空间格局在垂直和水平方向上进行温度场和风速场数值模拟,以探讨绿地空间格局对城市热环境的影响程度及方式。在绿地的垂直结构上,灌木层对流场的影响要大于乔木层;而乔木层对绿地内部的降温作用更为明显。在绿地的水平布局形式中,在绿地率相当的情况下,楔状格局具有较好的热环境效应,即该格局在城市中的降温效果最为明显;放射状和条带状的次之,点状格局对周边环境的降温效果要弱些,但各"绿点"(即组成该格局的各块绿地)在小范围内降温效果比较明显,可以作为改善局部小气候的手段;环状格局热环境效应最弱。将CFD技术引入城市热环境研究,利用遥感技术对其进行参数修正,使热环境研究更加准确完整,具有经济高效方便等优点。  相似文献   

13.
摘要:为了明确大豆航天搭载早期世代农艺性状选择的依据,提高航天搭载育种早期世代选择效果。对6个大豆品种经过航天搭载后的SP2代变异率和SP4代选择效果进行了分析,结果表明遗传力高的SP2代的单株荚数和单株粒数2个农艺性状的变异率与SP4代入选单株数相关达到极显著水平;SP2代遗传力较高底荚高度和节间长度的变异率与SP4代入选单株相关达到显著水平,SP2代遗传力不高的植株高度和主茎节数变异率与SP4代入选单株相关不显著;SP2代对单株荚数、单株粒数、底荚高度、节间长度进行选择有效,而对植株高度和主茎节数选择效果不明显。  相似文献   

14.
Climatic factors such as temperature and humidity vary seasonally in primate habitats; thus, behavioral adjustments and microhabitat selection by primate species have been interpreted as behavioral adaptations. François' langur (Trachypithecus francoisi), a native species to southwest China and northern Vietnam, inhabits a limestone habitat with extreme climatic conditions. To understand the potential effects of climatic seasonality on this species, we collected data on the individual behavioral budgets in a T. francoisi group between January and December 2010 in Fusui County, China. Monthly, we performed 5–11 days of observation during this period, using focal animal sampling and continuous recording methods. We also recorded ambient temperature (Ta) and relative humidity (Hr) data at our study site. Results indicated that Ta and Hr were significantly correlated with each other and fluctuated dramatically on a daily, monthly, and seasonal basis. The amount of time spent resting, grooming, basking, and huddling also varied on a daily, monthly, and seasonal basis. The proportion of resting time and total sedentary activity time significantly increased at high and low Tas, respectively. The total sedentary time, resting time, and plant branch use all showed positive significant correlations with Ta. Our results suggest that behavioral adjustment and support use of T. francoisi, at least partly, were related to thermoregulation. T. francoisi minimized thermal stress through behavioral adjustments and support use. It is an adaptive behavior associated with the climatic extremes of limestone habitat. This study can potentially advise conservation management strategies in this specific habitat. Conservation efforts should focus on vegetation restoration in langurs' habitat, including those in the foothills.  相似文献   

15.
To further study the characteristics of changes on the molecular level of rice mutants induced in space environment, we analyzed proteins in leaves and seeds of four rice mutants (two high-tillering and two low-tillering) in the 8th and 9th generations after a 15-day spaceflight, and compared with their ground controls by two-dimentional polyacrylamide gel electrophoresis and reverse phase liquid chromatography (RPLC). In addition, the albumin, globulin, prolamine, glutelin, and amylose of the mutant seeds were analyzed by RPLC and ultra-violet spectrometry. The results showed that the low-abundance proteins of leaves in the peak tillering stage are more likely to he induced compared with their corresponding controls. The albumin, globulin, and prolamine of the mutant seeds revealed changes when compared with their controls, and the characteristics of changes in different mu- tants were stably inherited in the 8th and 9th generations, suggesting that they can be used as biomarkers to identity the mutants induced by spaceflight. Moreover, two proteins (SSP9111 and SSP6302) were found to be expressed with high intensity (two-fold change) in different mutants, which were both correlated with photosystem according to mass spectrometry and database searching.  相似文献   

16.
17.
刘畅  徐宁  宋靖达  胡尚春 《生态学报》2017,37(10):3561-3569
选择黑龙江省森林植物园内景观差异性较大的4个样地。实地测量各样地空气温度、相对湿度、风速等小气候要素数据,问卷调查游人热舒适感受,观察记录游人空间选择及行为特征。旨在寻找小气候要素与人体热舒适感受的关系,以及游人空间选择与热舒适感受评价的关联程度。结果表明:各小气候要素均对游人热舒适感受有一定的影响,其中空气温度对游人热舒适感受影响最大,其次是相对湿度和风速;不同样地内游人对热舒适感受变化的敏感程度不同,水体和植物群落除了通过増湿降温作用调节空间热舒适感受外,其观赏作用也可以降低人们对热舒适感受变化的敏感性;遮荫是夏季游人选择休憩空间的主要因素。  相似文献   

18.
王凯  梁红  施鹏  赵鸣 《生态学报》2019,39(16):6051-6057
城市开放空间的风场不仅影响微环境的"风感"舒适度还影响宏观尺度的城市气候。从景感生态学的角度出发,首先阐述"风感"的定义,总结了街道峡谷空间风场的基本规律和特点。运用Kestrel NK4500手持气象站对城市开放空间的风环境进行实测,采用CFD(Computational Fluid Dynamics)模拟软件Fluent 14.0对不含绿地的同一空间进行风环境模拟,通过两者的数据比对来研究紧凑型城市开放空间内绿地对行人高度风场的实际干扰程度。结果发现,紧凑型城市开放空间的"风感"受建筑和绿地空间布局的共同影响。当建筑高于绿地时,风场受建筑的控制;当林带高于建筑时,林带对风环境的影响程度受其疏密度影响。疏密度较高的常绿林带对风向和风速影响很大,而疏密度较低的林带会影响风速,对风向影响不大。影响风速的主要因素是空间围合所形成的空气域,相比实体、多孔介质,空气域对风的阻力要小的多。如铺装、草坪上方的通风廊道是影响行人高度层通风、导风的关键因素。紧凑型空间内的绿地在行人高度应保持通畅以保证通风,并通过建立平面和竖向上的通风、导风廊道体系,促进空气循环。  相似文献   

19.
The ecological effects of climate change have been shown in most major taxonomic groups; however, the evolutionary consequences are less well‐documented. Adaptation to new climatic conditions offers a potential long‐term mechanism for species to maintain viability in rapidly changing environments, but mammalian examples remain scarce. The American pika (Ochotona princeps) has been impacted by recent climate‐associated extirpations and range‐wide reductions in population sizes, establishing it as a sentinel mammalian species for climate change. To investigate evidence for local adaptation and reconstruct patterns of genomic diversity and gene flow across rapidly changing environments, we used a space‐for‐time design and restriction site‐associated DNA sequencing to genotype American pikas along two steep elevational gradients at 30,966 SNPs and employed independent outlier detection methods that scanned for genotype‐environment associations. We identified 338 outlier SNPs detected by two separate analyses and/or replicated in both transects, several of which were annotated to genes involved in metabolic function and oxygen transport. Additionally, we found evidence of directional gene flow primarily downslope from high‐elevation populations, along with reduced gene flow at outlier loci. If this trend continues, elevational range contractions in American pikas will likely be from local extirpation rather than upward movement of low‐elevation individuals; this, in turn, could limit the potential for adaptation within this landscape. These findings are of particular relevance for future conservation and management of American pikas and other elevationally restricted, thermally sensitive species.  相似文献   

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