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1.
The Duke of Burgundy butterfly has undergone considerable range contractions across Europe and since the 1970s has lost around 84% of its former distribution in the UK. Despite its endangered status, the butterfly is understudied, with few papers directly investigating its habitat requirements. This limited research effort focusses on the larval life stage, with relatively little being known about the adults of the species. In this study, we investigated the habitat usage of both adults and larvae of the Duke of Burgundy. Fieldwork was carried out in association with the Bedfordshire, Cambridgeshire and Northamptonshire (BCN) Wildlife Trust on their Totternhoe Quarry Reserve in Bedfordshire. Using data collected over the course of a decade, we performed the first long term distribution analysis of the species and we identified habitat attributes associated with long-standing abundance hotspots of both adults and larvae on the reserve. We found both life stages to be conserved in their range, remaining in the same small areas of Totternhoe Quarry year on year, with adults often being more restricted in their distribution than larvae. Sheltered locations were important for both life stages, but small differences in habitat preference, such as slope and aspect, were also identified. These results emphasise the need to target management towards both life stages of the Duke of Burgundy, as supporting the larvae alone may not result in suitable environmental conditions for the adults.  相似文献   

2.
Mendenhall AR  LaRue B  Padilla PA 《Genetics》2006,174(3):1173-1187
Oxygen deprivation has a role in the pathology of many human diseases. Thus it is of interest in understanding the genetic and cellular responses to hypoxia or anoxia in oxygen-deprivation-tolerant organisms such as Caenorhabditis elegans. In C. elegans the DAF-2/DAF-16 pathway, an IGF-1/insulin-like signaling pathway, is involved with dauer formation, longevity, and stress resistance. In this report we compared the response of wild-type and daf-2(e1370) animals to anoxia. Unlike wild-type animals, the daf-2(e1370) animals have an enhanced anoxia-survival phenotype in that they survive long-term anoxia and high-temperature anoxia, do not accumulate significant tissue damage in either of these conditions, and are motile after 24 hr of anoxia. RNA interference was used to screen DAF-16-regulated genes that suppress the daf-2(e1370)-enhanced anoxia-survival phenotype. We identified gpd-2 and gpd-3, two nearly identical genes in an operon that encode the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase. We found that not only is the daf-2(e1370)-enhanced anoxia phenotype dependent upon gpd-2 and gpd-3, but also the motility of animals exposed to brief periods of anoxia is prematurely arrested in gpd-2/3(RNAi) and daf-2(e1370);gpd-2/3(RNAi) animals. These data suggest that gpd-2 and gpd-3 may serve a protective role in tissue exposed to oxygen deprivation.  相似文献   

3.
J Sasaki  A Mikami  K Mizoue    S Omura 《Applied microbiology》1991,57(10):2841-2846
To enzymatically synthesize vitamin D derivatives, we screened about 300 Streptomyces sp. strains. Streptomyces sclerotialus FERM BP-1370 and Streptomyces roseoporus FERM BP-1574 were found to have the ability to convert 25-hydroxyvitamin D3 and 1 alpha-hydroxyvitamin D3, respectively, to 1 alpha, 25-dihydroxyvitamin D3. The average rates of 1 alpha hydroxylation of 25-hydroxyvitamin D3 were 6.9 micrograms liter-1 min-1 with FERM BP-1370 and 7.0 micrograms liter-1 min-1 with FERM BP-1574. The specific cytochrome P-450 inhibitors carbon monoxide, SKF-525-A, and metyrapone inhibited the hydroxylation of 1 alpha- and 25-hydroxyvitamin D3 to 1 alpha, 25-dihydroxyvitamin D3 by FERM BP-1370 and FERM BP-1574. The cytochromes P-450 of these strains were detected by reduced CO difference spectra in the whole-cell suspensions. The appearance of cytochrome P-450 suggests that the cytochromes P-450 of FERM BP-1370 and FERM BP-1574 carry out the hydroxylation of 25- and 1 alpha-hydroxyvitamin D3 to 1 alpha, 25-dihydroxyvitamin D3.  相似文献   

4.
To enzymatically synthesize vitamin D derivatives, we screened about 300 Streptomyces sp. strains. Streptomyces sclerotialus FERM BP-1370 and Streptomyces roseoporus FERM BP-1574 were found to have the ability to convert 25-hydroxyvitamin D3 and 1 alpha-hydroxyvitamin D3, respectively, to 1 alpha, 25-dihydroxyvitamin D3. The average rates of 1 alpha hydroxylation of 25-hydroxyvitamin D3 were 6.9 micrograms liter-1 min-1 with FERM BP-1370 and 7.0 micrograms liter-1 min-1 with FERM BP-1574. The specific cytochrome P-450 inhibitors carbon monoxide, SKF-525-A, and metyrapone inhibited the hydroxylation of 1 alpha- and 25-hydroxyvitamin D3 to 1 alpha, 25-dihydroxyvitamin D3 by FERM BP-1370 and FERM BP-1574. The cytochromes P-450 of these strains were detected by reduced CO difference spectra in the whole-cell suspensions. The appearance of cytochrome P-450 suggests that the cytochromes P-450 of FERM BP-1370 and FERM BP-1574 carry out the hydroxylation of 25- and 1 alpha-hydroxyvitamin D3 to 1 alpha, 25-dihydroxyvitamin D3.  相似文献   

5.
Fabien Knoll 《Geobios》2009,42(6):755
The remains of an ornithopod dinosaur from the Upper Barremian (Lower Cretaceous) of Auxerre (Burgundy, France) are described. They consist of several vertebrae and a fragmentary scapula. Despite obvious morphological and dimensional affinities with the species Iguanodon bernissartensis, the state of the specimen does not allow any identification more precise than Iguanodontia indet. Reappraisal of the French Upper Barremian record of medium and large-sized ornithopods reveals that no specimen can be definitely determined to the specific level.  相似文献   

6.
The Duke of Burgundy butterfly (Hamearis lucina) has declined severely since the 1970s and is a UK Biodiversity Action Plan Priority species. Its populations are mostly confined to scrubby calcareous grassland, where management for short-turf species can be detrimental to the butterfly. We briefly review the literature on the Duke of Burgundy and investigate their habitat preferences, survival and dispersal at a chalk grassland reserve in Bedfordshire, UK. We found that adults generally preferred more sheltered locations but that their habitat preferences were less restrictive than choice of food-plants. Females chose larger plants with longer leaves in denser patches on which to lay eggs. Adults showed reasonable dispersal ability with turnover recorded between areas isolated by scrub. Our results indicate that the species is able to use isolated areas of favourable habitat at a reserve scale and that conservation could therefore involve cyclic management to provide suitable habitat year-to-year.  相似文献   

7.
研究了10种绿化树对VA菌根的依赖性、感染率及其接种效应。结果表明:各参试树种对VA菌根都有不同程度的感染率及依赖性;其中黑金刚(Ficus elastica cv.Deocora Burgundy)接种感染率最高,达90%,巴西榕(Ficus elastica cv. Variegaa)、竹节树(Carallia brachiata)的接种感染率大于80%,接种感染率大于60%的有花金刚(Ficus elastica cv. Decora Tricolor)、红关公(Ficus elastica cv. Decora)、扭纹铁(Dracaena deremensis)、红桂木(Artocarpus nitidus subsp. lingnanensis),小于35%的有红楣(Anneslea fragrans)、伞花木(Eurycorymbus cavaleriei)、石楠(Photinia serrulata);黑金刚、巴西榕对VA菌根的依赖度最高,都超过了300%,红关公、花金刚对VA菌根的依赖度中等,分别为213.3%、203.5%;红桂木、竹节树、扭纹铁、石楠、红楣、伞花木对VA菌根依赖性偏弱,依赖度都在200%以下。参试树种菌根感染率和依赖度的排序基本一致。VA菌根对各参试树种均有不同程度的接种效应,对黑金刚、花金刚、红关公、巴西榕和竹节树的接种效应最为明显,对扭纹铁、红桂木的接种效应较好,而对石楠、红楣和伞花木则稍差。  相似文献   

8.
Genetic variants within the endothelin-1 gene (EDN1) have been associated with several cardiovascular diseases and may act as genetic prognostic markers. Here, we explored the overall relevance of EDN1 polymorphisms for long-term survival in patients undergoing on-pump cardiac surgery. A prospectively collected cohort of 455 Caucasian patients who underwent cardiac surgery with cardiopulmonary bypass was followed up for 5 years. The obtained genotypes and inferred haplotypes were analyzed for their associations with the five-year mortality rate (primary endpoint). The EDN1 T-1370G and K198N genotype distributions did not deviate from Hardy–Weinberg equilibrium and the major allele frequencies were 83% and 77%, respectively. The cardiovascular risk factors were equally distributed in terms of the different genotypes and haplotypes associated with the two polymorphisms. The five-year mortality rate did not differ among the different EDN1 T-1370G and K198N genotypes and haplotypes. Haplotype analysis revealed that carriers of the G-T (compound EDN1 T-1370G G/K198N T) haplotype had a higher cardiac index than did non-carriers (p = 0.0008); however, this difference did not reach significance after adjusting for multiple testing. The results indicate that common variations in EDN1 do not act as prognostic markers for long-term survival in patients undergoing on-pump cardiac surgery.  相似文献   

9.
In this paper, we introduce a new estimator of a percentile residual life function with censored data under a monotonicity constraint. Specifically, it is assumed that the percentile residual life is a decreasing function. This assumption is useful when estimating the percentile residual life of units, which degenerate with age. We establish a law of the iterated logarithm for the proposed estimator, and its ‐equivalence to the unrestricted estimator. The asymptotic normal distribution of the estimator and its strong approximation to a Gaussian process are also established. We investigate the finite sample performance of the monotone estimator in an extensive simulation study. Finally, data from a clinical trial in primary biliary cirrhosis of the liver are analyzed with the proposed methods. One of the conclusions of our work is that the restricted estimator may be much more efficient than the unrestricted one.  相似文献   

10.
Relationships among elevation, foliar morphology, spectral reflectance, and chlorophyll fluorescence of two co-occurring montane conifers, red spruce (Picea rubens Sarg.) and balsam fir (Abies balsamea [L.] Mill.), were investigated along two transects from 460 to 1460 m on Mt. Moosilauke in the White Mountains of New Hampshire, USA. Spectral reflectance (300-1100 nm wavelengths) and the chlorophyll fluorescence F(v)/F(m) ratio were measured on dark-adapted needles. Foliar morphology (needle size, shape, and mass) and nitrogen concentrations were measured in the laboratory. Reflectance spectra varied between species and with elevation. Two chlorophyll measures, red edge position and a chlorophyll-based difference index (Chl NDI = R750 - R705/R750 + R705), indicated more chlorophyll in fir than in spruce and decreasing chlorophyll with increasing elevation in both species. The structure-independent pigment index (SIPI = R800 - R445/R800 - R680) increased with elevation, indicating an increasing carotenoid?:?chlorophyll ratio. The photochemical reflectance index (PRI = R531 - R570/R531 + R570), a measure of photosynthetic radiation use efficiency, decreased with increasing elevation up to 1370 m. In the highest elevation site, within the stunted alpine krummholz at 1460 m, PRI was higher than at 1370 m, but still lower than at 1070 m. This same pattern was evident in the chlorophyll fluorescence F(v)/F(m) measurements. These independent indices indicate higher stress in spruce than fir, which may be related to the "spruce decline" reported in the northeastern USA. Results also indicate progressively increasing stress with increasing elevation up to 1370 m. Stress appears to be lower at 1460 m than at 1370 m, despite the harsher conditions at the very summit of Mt. Moosilauke. This may be a consequence of stress-tolerant physiology and/or prostrate architecture.  相似文献   

11.
We report evidence for the existence of a putative ABC transporter for corrinoid utilization in the extremely halophilic archaeon Halobacterium sp. strain NRC-1. Results from genetic and nutritional analyses of Halobacterium showed that mutants with lesions in open reading frames (ORFs) Vng1370G, Vng1371Gm, and Vng1369G required a 10(5)-fold higher concentration of cobalamin for growth than the wild-type or parent strain. The data support the conclusion that these ORFs encode orthologs of the bacterial cobalamin ABC transporter permease (btuC; Vng1370G), ATPase (btuD; Vng1371Gm), and substrate-binding protein (btuF; Vng1369G) components. Mutations in the Vng1370G, Vng1371Gm, and Vng1369G genes were epistatic, consistent with the hypothesis that their products work together to accomplish the same function. Extracts of btuF mutant strains grown in the presence of cobalamin did not contain any cobalamin molecules detectable by a sensitive bioassay, whereas btuCD mutant strain extracts did. The data are consistent with the hypothesis that the BtuF protein is exported to the extracellular side of the cell membrane, where it can bind cobalamin in the absence of BtuC and BtuD. Our data also provide evidence for the regulation of corrinoid transport and biosynthesis. Halobacterium synthesized cobalamin in a chemically defined medium lacking corrinoid precursors. To the best of our knowledge, this is the first genetic analysis of an archaeal corrinoid transport system.  相似文献   

12.
Pollen counts in Burgundy were monitored by means of four Hirst volumetric traps. Their analysis revealed a sharp rise of Ambrosia from 1996 to 1997. The minimum amount of ragweed pollen likely to provoke allergies (13 grains m–3) was reached or exceeded several days every year, but without leading to clinical symptoms. The circadian variation of Ambrosia pollen showed two peaks: the first one in the morning was suggested to coincide with local pollination, although the second one, in the afternoon, seemed to result from a long range transport which was confirmed by the study of wind roses.  相似文献   

13.
14.
15.
S Kim  EJ Shin  JH Hahm  PJ Park  JE Hwang  YK Paik 《PloS one》2012,7(7):e41755
In Caenorhabditis elegans, slow fat consumption has been suggested to contribute to the extension of the survival rate during nutritionally adverse conditions. Here, we investigated the potential role of pyruvate dehydrogenase kinase (PDHK)-2, the C. elegans homolog of mammalian PDK, effects on fat metabolism under nutritional conditions. PDHK-2 was expressed at low levels under well-fed conditions but was highly induced during long-term starvation and in the dauer state. This increase in pdhk-2 expression was regulated by both DAF-16 and NHR-49. Dauer-specific induction of PDHK-2 was abolished upon entry into the post-dauer stage. Interestingly, in the long-term dauer state, stored fat levels were higher in daf-2(e1370);pdhk-2 double mutants than in daf-2(e1370), suggesting a positive relationship between PDHK-2 activity and fat consumption. PDHK-2 deficiency has been shown to lead to greater preservation of residual fats, which would be predicted to contribute to survival during the dauer state. A test of this prediction showed that the survival rates of daf-2(e1370);pdhk-2(tm3075) and daf-2(e1370);pdhk-2(tm3086) double mutants were higher than that of daf-2(e1370), suggesting that loss of either the ATP-binding domain (tm3075) or branched chain keto-acid dehydrogenase kinase domain (tm3086) of PDHK-2 leads to reduced fat consumption and thus favors increased dauer survival. This attenuated fat consumption in the long-term dauer state of C. elegans daf-2 (e1370);pdhk-2 mutants was associated with concomitant down-regulation of the lipases ATGL (adipose triglyceride lipase), HSL (hormone-sensitive lipase), and C07E3.9 (phospholipase). In contrast, PDHK-2 overexpression in wild-type starved worms induced lipase expression and promoted abnormal dauer formation. Thus, we propose that PDHK-2 serves as a molecular bridge, connecting fat metabolism and survival under nutritionally adverse conditions in C. elegans.  相似文献   

16.
经过五年来对稻纵卷叶螟自然种群生命表的研究,组建了预测种群动态的生命系统模拟模型。本模型为一变维矩阵组合模型。除能随环境温度而改变矩阵维数外,采用生理年龄为矩阵步长。每一虫期内各个体的发育不一致,矩阵中各元素均为某些环境因素的函数,共组建有18个子模式。在输入起始日期,预测期限,水稻生育期,环境温、湿度和初始种群各年龄向量后,即可自动打印出逐日种群年龄向量及总虫量。计算机模拟曲线与实测曲线基本吻合。本模型可用来预测南京地区稻纵卷叶螟二代迁入峰后种群的发展以至第三代种群各虫态的起始虫量和发生期。  相似文献   

17.

Background  

The gene daf-2 encodes the single insulin/insulin growth factor-1-like receptor of Caenorhabditis elegans. The reduction-of-function allele e1370 induces several metabolic alterations and doubles lifespan.  相似文献   

18.
During the summer of 2007 several Greek regions suffered periods of extreme heat, with midday temperatures of over 40°C on several consecutive days. High temperatures were also recorded on the east coast of central Greece, where a complex sea breeze circulation system frequently develops. The more intense events occurred at the end of June and July. The highest temperatures were observed on 26 June and 25 July, while the sea breeze developed only on 25 July. Meteorological data collected at two sites—a coastal urban location and an inland suburban site that is not reached by the sea breeze flow—as well as pollution data collected at the urban site, were analysed in order to investigate the relationship between sea breeze development and the prevailing environmental conditions during these two heat wave events. The analysis revealed that sea breeze development affects temperature and pollution levels at the shoreline significantly, causing a decrease of ~4°C from the maximum temperature value and an increase of ~30% in peak PM10 levels. Additionally, several stress indices were calculated in order to assess heat comfort conditions at the two sites. It was found that nocturnal comfort levels are determined mainly by the urban heat island effect, the intensity of which reaches up to 8°C, while the applied indices do not demonstrate any significant daytime thermal stress relief due to sea breeze development.  相似文献   

19.
The Grotte du Renne at Arcy-sur-Cure (Burgundy, France) has yielded remains from several occupation layers, extending from the end of the middle Palaeolithic to the upper Palaeolithic. The last Mousterian layer (XI), which precedes the Châtelperronian occupations (layers Xa, Xb, Xc, IX, VIII), was previously interpreted as a precursor of the transition complex. The new study of the lithic assemblage of layer XI, in the context of the other final Mousterian occupations in Arcy (Grotte du Bison, Galerie Schoepflin Rotonde, Grotte de l’Hyène) challenges this hypothesis. The Mousterian Arcy complex can be divided into three main techno-complexes: Levallois–Charentian, Discoid–Denticulate and Levallois Mousterian. We observed a rupture between the final Mousterian and Châtelperronian industries as regards all the aspects of the technical system; production methods, blank management, tool types, and some changes in raw material composition.  相似文献   

20.
Two single assemblages of cereals and chaff from the oppidum Bibracte, (Burgundy, France), give evidence of cereal trade, food supply and crop processing in late Celtic and early Roman times. The first deposit consists mainly of Triticum dicoccon chaff which was buried in a wooden box near the sanctuary of La Terrasse. The second assemblage was a store of different wheats and barley excavated in a Roman cellar at the Pature du Couvent. The analyses of these finds are presented, and recent archaeobotanical research at Mont Beuvray is summarized.  相似文献   

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