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71.
Parisi M Nuttall R Naiman D Bouffard G Malley J Andrews J Eastman S Oliver B 《Science (New York, N.Y.)》2003,299(5607):697-700
Sex chromosomes are primary determinants of sexual dimorphism in many organisms. These chromosomes are thought to arise via the divergence of an ancestral autosome pair and are almost certainly influenced by differing selection in males and females. Exploring how sex chromosomes differ from autosomes is highly amenable to genomic analysis. We examined global gene expression in Drosophila melanogaster and report a dramatic underrepresentation of X-chromosome genes showing high relative expression in males. Using comparative genomics, we find that these same X-chromosome genes are exceptionally poorly conserved in the mosquito Anopheles gambiae. These data indicate that the X chromosome is a disfavored location for genes selectively expressed in males. 相似文献
72.
Epstein EE Soter SL Oliver JP Schorn RA Wilson WJ 《Science (New York, N.Y.)》1967,157(3796):1550-1552
Observations of the 3.4-millimeter radio emission from Mercury during 1965 and 1966 yielded the following relationship between average brightness temperature T(B) of the disk and the planetocentric phase angle i: T(B) = 277 (+/- 12) + 97 (+/- 17) cos [i + 29 deg (+/- 10 deg)] degrees K The errors are statistical standard; the phase shift corresponds to a phase lag-that is, the maximum and minimum of insolation lag the maximum and minimum of planetary radiation. 相似文献
73.
Gene regulation by transcription factors and microRNAs 总被引:1,自引:0,他引:1
Hobert O 《Science (New York, N.Y.)》2008,319(5871):1785-1786
74.
Einsle O Tezcan FA Andrade SL Schmid B Yoshida M Howard JB Rees DC 《Science (New York, N.Y.)》2002,297(5587):1696-1700
A high-resolution crystallographic analysis of the nitrogenase MoFe-protein reveals a previously unrecognized ligand coordinated to six iron atoms in the center of the catalytically essential FeMo-cofactor. The electron density for this ligand is masked in structures with resolutions lower than 1.55 angstroms, owing to Fourier series termination ripples from the surrounding iron and sulfur atoms in the cofactor. The central atom completes an approximate tetrahedral coordination for the six iron atoms, instead of the trigonal coordination proposed on the basis of lower resolution structures. The crystallographic refinement at 1.16 angstrom resolution is consistent with this newly detected component being a light element, most plausibly nitrogen. The presence of a nitrogen atom in the cofactor would have important implications for the mechanism of dinitrogen reduction by nitrogenase. 相似文献
75.
Eastern Germany is often hit by drought causing income risk for crop farmers. Index-based risk management instruments could help crop farmers to reduce their farm income risk. Such instruments have some important advantages over damage-based insurance, like e.g. less moral hazard and adverse selection. At the same time they typically have a high level of basis risk. Up to now, mainly precipitation-based weather derivatives have been discussed as an appropriate risk management instrument for farmers in Germany. As a potentially more effective alternative, we propose water capacity-based index insurance. In order to show the benefits of a precipitation-based and water capacity-based index insurance, several contract designs are compared. Using a whole farm risk program planning approach, we show that for an average agricultural producer in Eastern Germany water capacity-based index insurance offers greater benefits than precipitation-based index insurance. 相似文献
76.
Rosalind Bryce Matthew K. Oliver Llinos Davies Helen Gray Jamie Urquhart Xavier Lambin 《Biological conservation》2011,(1):575-583
Successful eradications of harmful invasive species have been mostly confined to islands while control programs in mainland areas remain small, uncoordinated and vulnerable to recolonisation. To allow the recovery of threatened native species, innovative management strategies are required to remove invasives from large areas. We took an adaptive approach to achieve large scale eradication of invasive American mink in North East Scotland. The project was centred on the Cairngorms National Park (Scotland), with the primary aim of protecting endangered water vole populations. The project was initiated by scientists and supported and implemented through a partnership comprising a government agency, national park authority and local fisheries boards. Capitalising on the convergent interests of a diverse range of local stakeholders, we created a coordinated coalition of trained volunteers to detect and trap mink. Starting in montane headwaters, we systematically moved down river catchments, deploying mink rafts, an effective detection and trapping platform. Volunteers took increasing responsibility for raft monitoring and mink trapping as the project progressed. Within 3 years, the project removed 376 mink from 10570 km2 with the involvement of 186 volunteers. Capture rate within sub-catchments increased with greater connectivity to mink in other sub-catchments and with proximity to the coast where there is more productive habitat. The main factor underpinning the success of this project was functional volunteer participation. The project is a reason for optimism that the tide of invasion can be rolled back on a large scale where the convergent interest of local communities can be harnessed. 相似文献
77.
A 4-month-old intact male domestic shorthair cat was evaluated for urinary outflow obstruction after several weeks of medical management for traumatic urethral rupture. Positive-contrast retrograde urethrography and anterograde cystoscopy performed 4 weeks after the initial urethral injury confirmed a stricture approximately 1cm distal to the bladder trigone at the site of the initial urethral tear. A self-expanding metallic urethral stent (SEMS) was placed under fluoroscopic guidance to relieve the urethral stricture and re-establish luminal patency. After stent placement, the cat was able to void urine normally with minimal urinary incontinence noted. This resolved several months post-stent placement. No known clinical complications persisted other than mild intermittent hematuria. 相似文献
78.
Gould D Pettitt L McLaughlin B Holmes N Forman O Thomas A Ahonen S Lohi H O'Leary C Sargan D Mellersh C 《Veterinary ophthalmology》2011,14(6):378-384
Primary lens luxation (PLL) is a well-recognized, painful and potentially blinding inherited ocular condition in dogs. We screened PLL-affected dogs of 30 different breeds, to identify those which carried a previously described c.1473+1 G>A mutation in ADAMTS17 that is associated with PLL in Miniature Bull terriers, Lancashire Heelers, and Jack Russell terriers. This ADAMTS17 mutation was identified in PLL-affected dogs from 14 additional breeds. PLL-affected dogs from some breeds (most notably the Shar pei and the Brittany spaniel) did not carry the G1473+1A ADAMTS17 mutation, indicating they must suffer from a genetically distinct form of the condition. We also estimated the frequency of this ADAMTS17 mutation in some of the breeds. Our findings indicate the mutation segregates in a large number of different breeds of dog, many of which are terriers or breeds with terrier co-ancestry, but some of which have more diverse origins. Our results also indicate that the mutation is present at high frequency within most of the breeds in which it segregates. In the miniature bull terrier breed estimates of mutation frequency ranged from 0.27 to 0.39, corresponding to 7.3-15.2% PLL-affected dogs in this breed. We also identified an increased risk of PLL associated with heterozygosity at ADAMTS17, suggesting that carriers carry a low risk of developing PLL. 相似文献
79.
Mitteilungen
Patentierung in der Pflanzenzüchtung 相似文献80.
Oliver A. H. Jones Mahon L. Maguire Julian L. Griffin Young-Ho Jung Junko Shibato Randeep Rakwal Ganesh K. Agrawal Nam-Soo Jwa 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(4):539-554
A metabolomics based approach has been used to study the infection of the Hwacheong rice cultivar (Oryza sativa L. cv. Hwacheong) with compatible (KJ201) and incompatible (KJ401) strains of the rice blast fungal pathogen Magnaporthe grisea. The metabolic response of the rice plants to each strain was assessed 0, 6, 12, 24, 36, and 48 h post inoculation. Nuclear
Magnetic Resonance (NMR) spectroscopy and Gas and Liquid Chromatography Tandem Mass spectrometry (GC/LC-MS/MS) were used to
study both aqueous and organic phase metabolites, collectively resulting in the identification of 93 compounds. Clear metabolic
profiles were observed at each time point but there were no significant differences in the metabolic response elicited by
each pathogen strain until 24 h post inoculation. The largest change was found to be in alanine, which was ~30% (±9%) higher
in the leaves from the compatible, compared to the resistant, plants. Together with several other metabolites (malate, glutamine,
proline, cinnamate and an unknown sugar) alanine exhibited a good correlation between time of fungal penetration into the
leaf and the divergence of metabolite profiles in each interaction. The results indicate both that a wide range of metabolites
can be identified in rice leaves and that metabolomics has potential for the study of biochemical changes in plant-pathogen
interactions. 相似文献