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121.
Short NM 《Science (New York, N.Y.)》1966,154(3747):382-384
Loose quartz grains packed around chemical explosives are forced during cratering explosions into compacted, coherent masses resembling sand stone blocks found at certain meteorite craters. Sandstone-like lumps found at the Wabar (Arabia) meteorite craters are similar to these shock-lithified sands. Shock-lithification by impact may be effected on Moon as large meteorites strike surfaces covered with rubble from earlier collisions. 相似文献
122.
Comparative metagenomics of microbial communities 总被引:1,自引:0,他引:1
Tringe SG von Mering C Kobayashi A Salamov AA Chen K Chang HW Podar M Short JM Mathur EJ Detter JC Bork P Hugenholtz P Rubin EM 《Science (New York, N.Y.)》2005,308(5721):554-557
The species complexity of microbial communities and challenges in culturing representative isolates make it difficult to obtain assembled genomes. Here we characterize and compare the metabolic capabilities of terrestrial and marine microbial communities using largely unassembled sequence data obtained by shotgun sequencing DNA isolated from the various environments. Quantitative gene content analysis reveals habitat-specific fingerprints that reflect known characteristics of the sampled environments. The identification of environment-specific genes through a gene-centric comparative analysis presents new opportunities for interpreting and diagnosing environments. 相似文献
123.
CE Ugarte DG Thomas RB Gasser M Hu I Scott MG Collett 《New Zealand veterinary journal》2013,61(5):347-351
CASE HISTORY: A feral cat captured in the Manawatu region of New Zealand was treated for worms and fleas, and kept confined in a metabolic cage. It showed good appetite and weight gain but had intermittent watery, yellow diarrhoea. CLINICAL FINDINGS: Clinical examination under sedation was unremarkable and routine blood tests showed no significant abnormalities. The cat was negative for feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). Different canned cat foods did not alter the course of the diarrhoea, and the cat was euthanised 6 months after capture. At necropsy, two sections of adult Spirometra tapeworms were found in the jejunum and typical Spirometra eggs were found in colonic contents. Molecular identification of the parasite was undertaken, using the cytochrome- c oxidase subunit-1 gene (cox1) sequence. DIAGNOSIS: Chronic intermittent diarrhoea associated with Spirometra erinacei / S. erinaceieuropaei infection. CLINICAL RELEVANCE: Spirometra has not been reported in New Zealand before but has been associated with gastrointestinal disease in cats in other parts of the world. It requires speciestargeted treatment to be eliminated effectively, and is zoonotic. Diagnosis could be diffi cult for clinicians who are not familiar with the parasite and its life cycle. 相似文献
124.
Ruijun Ma Alex McBratney Brett Whelan Budiman Minasny Michael Short 《Precision Agriculture》2011,12(1):55-66
There are various factors that affect soil electrical conductivity (EC) measurements, including soil texture, soil water content,
cation exchange capacity (CEC) and others. Temperature is an important environmental variable, and different models can be
used to correct for its effect on EC measurements and standardize the measurements to 25°C. It is relevant to analyze these
models and to determine whether they are consistent with each other. Some models were wrongly cited. We found that the exponential
model of Sheets and Hendrickx as corrected by Corwin and Lesch in 2005 performs the best. The ratio model also performs well
between 3°C and 47°C. 相似文献
125.
Annabelle J Bladon Katherine M Short Essam Yassin Mohammed E J Milner‐Gulland 《Fish and Fisheries》2016,17(3):839-859
Payments for Ecosystem Services (PES) is a powerful economic tool that gives positive conditional incentives for the provision of additional ecosystem services over the status quo, which has been used widely in terrestrial conservation. Interest in the concept of marine PES has recently emerged, but the fluid, transboundary and often common pool nature of marine ecosystems presents challenges for PES design and implementation. Here, we consider the potential role of PES in addressing current gaps in fisheries management. Used in combination with conventional regulatory approaches, PES may increase private sector engagement and generate more sustainable financing for fisheries management whilst spreading accountability throughout the supply chain. The approach is most likely to be feasible and effective in commercially valuable fisheries with: (i) demand for one or more ecosystem service and a threat to supply; (ii) suitable baseline data available and potential management actions underpinned by robust science; (iii) clarity and security of property rights; (iv) capacity for hybrid multi‐level governance; (v) capacity for rigorous monitoring, control and surveillance; and (vi) potential for financial sustainability of the scheme. An examination of four contrasting fisheries – Namibian hake, Mozambican shallow‐water shrimp, Western and Central Pacific skipjack tuna and Bangladesh hilsa – demonstrates that a developing world fishery will rarely fulfil each of these preconditions a priori, but that the potential for successful application of PES still exists. In practice, PES design will depend on the institutional context and require creative and innovative approaches to the maintenance of conditionality and additionality. 相似文献
126.
Emilio A. Herrera Jorge G. Farías Alejandro González-Candia Stefania E. Short Catalina Carrasco-Pozo Rodrigo L. Castillo 《Marine drugs》2015,13(2):838-860
Intermittent hypobaric hypoxia (IH) is linked with oxidative stress, impairing cardiac function. However, early IH also activate cardio-protective mechanisms. Omega 3 fatty acids (Ω3) induce cardioprotection by reducing infarct size and reinforcing antioxidant defenses. The aim of this work was to determine the combined effects of IH and Ω3 on cardiac function; oxidative balance and inflammatory state. Twenty-eight rats were randomly divided into four groups: normobaric normoxia (N); N + Ω3 (0.3 g·kg−1·day−1); IH; and IH + Ω3. IH was induced by 4 intercalate periods of hypoxia (4 days)—normoxia (4 days) in a hypobaric chamber during 32 days. At the end of the exposure, hearts were mounted in a Langendorff system and subjected to 30 min of ischemia followed by 120 min of reperfusion. In addition, we determined HIF-1α and ATP levels, as well as oxidative stress by malondialdehyde and nitrotyrosine quantification. Further, the expression of the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase was determined. NF-kappaB and myeloperoxidase levels were assessed in the hearts. Relative to N hearts, IH improved left ventricular function (Left ventricular developed pressure: N; 21.8 ± 3.4 vs. IH; 42.8 ± 7.1 mmHg; p < 0.05); reduced oxidative stress (Malondialdehyde: N; 14.4 ± 1.8 vs. IH; 7.3 ± 2.1 μmol/mg prot.; p < 0.05); and increased antioxidant enzymes expression. Supplementation with Ω3 induces similar responses as IH group. Our findings suggest that both, IH and Ω3 in an independent manner, induce functional improvement by antioxidant and anti-inflammatory mechanisms, establishing cardio-protection. 相似文献
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