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221.
Ren D Tu HC Kim H Wang GX Bean GR Takeuchi O Jeffers JR Zambetti GP Hsieh JJ Cheng EH 《Science (New York, N.Y.)》2010,330(6009):1390-1393
Although the proteins BAX and BAK are required for initiation of apoptosis at the mitochondria, how BAX and BAK are activated remains unsettled. We provide in vivo evidence demonstrating an essential role of the proteins BID, BIM, and PUMA in activating BAX and BAK. Bid, Bim, and Puma triple-knockout mice showed the same developmental defects that are associated with deficiency of Bax and Bak, including persistent interdigital webs and imperforate vaginas. Genetic deletion of Bid, Bim, and Puma prevented the homo-oligomerization of BAX and BAK, and thereby cytochrome c-mediated activation of caspases in response to diverse death signals in neurons and T lymphocytes, despite the presence of other BH3-only molecules. Thus, many forms of apoptosis require direct activation of BAX and BAK at the mitochondria by a member of the BID, BIM, or PUMA family of proteins. 相似文献
222.
Two common production constraints of dry bean (Phaseolus vulgaris) in Ontario are annual weeds and anthracnose (caused by Colletotrichum lindemuthianum). Dry bean is not considered a competitive crop and weed interference can result in substantial yield losses, while anthracnose is considered one of the most devastating diseases in dry bean production. A study conducted in Ontario Canada, examined the effect of two herbicide programs on weed management, thiamethoxam insecticide treatment on plant enhancement and three fungicide programs on anthracnose development in a navy bean cv. ‘OAC Rex’. The premium herbicide program (s-metolachlor + imazethapyr) reduced percent weed ground cover relative to the economic herbicide program (trifluralin) in five of six locations. Thiamethoxam increased emergence and vigour at only one location, which contradicts reported benefits of thiamethoxam on plant health. The herbicide or thiamethoxam treatments did not affect anthracnose disease severity, visible seed quality, net yield or economic return. The fungicide seed treatment was often superior to the untreated control, for a number of the parameters measured. The application date of the foliar fungicide, relative to the onset of disease, varied between site-years. This dramatically influenced the fungicide’s effectiveness. Foliar fungicides increased seed quality and net economic return compared to the control when applied prior to disease development. The combination of fungicide seed treatment followed by a foliar fungicide provided the largest reduction in anthracnose severity. 相似文献
223.
Nicholas P. L. Tuckey Gerard J. A. Janssen Malcolm E. Forster Steven P. Gieseg 《Journal Of Aquatic Food Product Technology》2013,22(2):156-167
Perfusion of fish tissues may provide a model for manipulating their properties post-harvest. Perfusion of Chinook salmon (Oncorhynchus tshawytscha) tails in vitro with oxygenated physiological saline at 5°C showed delivery to the muscle was at the ratio of 5.8:1 red:white muscle, respectively. Treatment with sodium nitroprusside (a nitric oxide donor) did not improve delivery to the white muscle. Perfusion at 15°C with and without ascorbic and uric acids showed that the inclusion of antioxidants reduced protein oxidation but did not reduce lipid peroxidation in the red muscle. This technique, with further development, shows potential as a post-mortem research tool. 相似文献
224.
Maurício Emerenciano Gerard Cuzon Miguel Arévalo Maite Mascaró Miquelajauregui Gabriela Gaxiola 《Aquaculture International》2013,21(5):987-1007
A 40-day trial was performed to evaluate the effect of short-term natural fresh food (FF) supplementation 20 days prior to ablation in Litopenaeus vannamei broodstock raised under biofloc conditions. Changes in biochemical composition and fatty acids profile were used as indicators of nutritional condition. Females that received FF supplementation (FLOC + FF) achieved better eggs production, spawned more promptly, and presented higher levels of HUFA in eggs as compared to those that did not received FF (FLOC). Proximate analysis of biofloc and microorganisms assessment showed a higher crude protein and lipid content in the FLOC + FF treatment (26.3 and 0.7 %) compared to FLOC treatment (18.4 and 0.3 %) and also demonstrated a higher concentration of filamentous cyanobacteria and nematodes. The better outcomes obtained in females that received short-term FF supplementation justified the FF use in L. vannamei broodstock. 相似文献
225.
Maurício Emerenciano Gerard Cuzon Adriana Paredes Gabriela Gaxiola 《Aquaculture International》2013,21(6):1381-1394
In a 210d experiment, the potential of biofloc technology (BFT) was evaluated for Farfantepenaeus duorarum. Water quality parameters, microorganisms profile and proximate analysis of biofloc were also assessed. BFT did not improve the growth performance in F. duorarum when compared to conventional clear-water water exchange system (final weight and survival of 13.3 g and 63.2 %; and 13.9 g and 81.4 %, respectively). Microorganism assessment suggested a higher presence of filamentous cyanobacteria followed by protozoa, nematodes and copepods. Proximate analysis of biofloc showed crude protein and crude lipid means levels of 25 and 0.6 %, respectively, and these values varied during the experiment. F. duorarum seemed to be susceptible to high stocking density and high levels of suspended solids (>15 mL L?1). 相似文献
226.
Barry Mc Inerney Gerard CorkeryGashaw Ayalew Shane WardKevin Mc Donnell 《Computers and Electronics in Agriculture》2011,77(1):1-6
The feasibility of using GS1 DataMatrix (GS1 DM) barcodes laser printed onto the beaks of poultry as a possible method of identification and, therefore, traceability of the individual were examined in this study, including a preliminary live trial on layer hens. The optimal laser type and settings for this particular application had been selected during previous in vitro and in vivo trials. GS1 DM barcodes were printed on both sides of the beaks of mature layer hens and read using a high specification camera based 1-Dimensional/2-Dimensional (1-D/2-D) DataMan 7500 barcode reader. The reading procedure was repeated on a number of occasions over a 5 week period to examine the effects of time in a commercial environment on the clarity and readability of the GS1 DM barcode, and the ability of the printed GS1 DM barcodes to resist the physical and chemical challenges of such a setting. The results show a very short timeframe during which all barcodes, both right and left combined, remain readable. Thereafter the readability deteriorates rapidly, due to the growth and healing of the beaks of the layer hens. Results also show that there was no significant difference in the readability between GS1 DM barcodes printed on the right or left side of the beak. The proportion of identification (ι) (i.e. number of layers identifiable by either one or two readable GS1 DM barcodes) was also calculated. All layer hens were fully identifiable for a seven day period by either one or two readable GS1 DM barcodes. Further analysis showed that the proportion of identification (ι) was significantly higher for layer hens when identified with two GS1 DM barcodes as opposed to just one. Secure movement control of live mature poultry at vulnerable points in the food chain, such as transfer of ownership, could well be facilitated by the use of this technology, thereby preventing fraud or substitution at these points. 相似文献
227.
Hui-Hua Lee Kevin R. Piner Michael G. Hinton Yi-Jay Chang Ai Kimoto Minoru Kanaiwa Nan-Jay Su William Walsh Chi-Lu Sun Gerard DiNardo 《Fisheries Science》2014,80(5):869-878
The population dynamics of the blue marlin Makaira nigricans stock in the Pacific Ocean were estimated for 1971–2011 using a fully integrated length-based, age-, and sex-structured model. Fishery-specific catch, size composition, and catch-per-unit of effort were used in the modeling as likelihood components. Estimated dynamics were consistent with a stock that is fully exploited and stable over the last several years. No significant trends in recruitment were noted; however, female blue marlin were estimated to make up a majority of the catch, and historical exploitation has disproportionately changed the age structure of females relative to males. This result is due to differences in assumed life history and estimated selectivity. Changes to important life history parameters that are responsible for the productivity of the stock would potentially change the interpretation of current stock status. 相似文献
228.
Eric Bideau Denis Picot Jean-Pierre Hamard Philippe Ballon Jean-François Gerard 《Scandinavian Journal of Forest Research》2016,31(1):40-45
We studied the effect of roe deer (Capreolus capreolus) browsing on the growth and mortality of sessile oak (Quercus petraea) seedlings. First, we measured the height and basal diameter, and counted the number of shoots of the 849 seedlings of an experimental plantation, 60 of which were individually protected by fencing. We then introduced two tame roe deer females every day for three weeks from late May to mid-June. Measurements and counts were repeated after roe deer removal, then once again the following winter. We found no significant effect of browsing on mortality, total height, or basal diameter of the seedlings. However, the browsed seedlings exhibited a lower number of shoots despite regrowth observed after roe deer removal. We propose to use the tolerance of oak to deer browsing to promote natural and inexpensive methods, to protect oak during regeneration, such as the spatial arrangement of plants or the use of slash or surrounding vegetation in favourable environments. 相似文献
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