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11.
Soybean [Glycine max (L.) Merrill] yield and seed fatty acids, protein, and oil content are important traits for which an improved understanding of significant genomic regions would be useful. To accomplish this, a soybean population consisting of 203 F5 derived recombinant inbred lines (RILs) was developed and genotyped with 11,633 polymorphic single nucleotide polymorphisms (SNPs). Each RIL was grown in a single plot at Knoxville, TN in 2010; followed by replicated, multi-location field trials in 2013 and 2014. The data from 2010, 2013, and 2014 were analyzed together in order to detect quantitative trait loci (QTL) for these traits, and 30 total QTLs were detected. Five QTLs are candidates for confirmed status and one QTL is a candidate for positional confirmation. Many of the genes with mutations in close proximity to the fatty acid QTLs are involved in biological processes for fatty acids and/or lipids and could be considered possible candidate genes. Similarly, genes with mutations in genomic regions near yield, protein, and oil QTLs were plentiful and may contribute to the variation observed in these traits. Except for yield and stearic acid, each trait displayed pleiotropic effects with other traits in this study. Notable are the pleiotropic effects for oleic and linolenic acid on chromosomes 9, 13, and 19. Overall, the findings from this research contribute new information to the genetic understanding of soybean yield and seed fatty acids, protein and oil content. This understanding will be useful in making trait improvements.  相似文献   
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When injected into cockroaches (Periplaneta americana), dihydropyrazoles (pyrazolines), e.g. RH 3421, methyl 1-(N-(α,α,α-trifluoro-p-tolyl)carbamoyl-3-(4-chlorophenyl)-4-methyl-2-pyrazolin-4-ylcarboxylate, caused incoordination, followed by prostration and violent tremors. After several hours, prostrate cockroaches became very still, appearing paralyzed, but for several days they retained the ability to produce violent tremors when physically disturbed. The paralysis was associated with block of spontaneous activity in sensory nerves of cockroaches, tobacco hornworm larvae (Manduca sexta) and housefly larvae (Musca domestica). Block of spontaneous central nervous system activity was also seen in some cases. Current-clamp experiments on the cell body of the crayfish slowly-adapting stretch receptor neuron revealed that spike initiation in response to injected current was blocked by dihydropyrazoles, with no change in resting potential or input resistance, suggesting that the sodium current was suppressed. Hyperpolarization of blocked stretch receptors could reverse block, and crayfish giant axons, which were not normally sensitive to block by dihydropyrazoles, were rendered sensitive when artificially depolarized by elevation of extracellular potassium ion concentration, leading to the conclusion that the block of sodium current was strongly voltage dependent. The proposed mode of action, while similar to that of local anesthetics, class I anticonvulsants and class I antiarrhythmics, is novel for an insecticide.  相似文献   
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An hexane extract from roots of Black Boo Stammi, a cultivar of date palm, resistant toFusarium oxysporum f. sp.albedinis, contained substances which inhibited the spore germination and the growth of the germ tubes of the three isolates of the pathogen that were tested. Extract from roots of Jihel, a susceptible cultivar, lacked these substances.Samenvatting In een hexaanextract van wortels van de dadelpalm, cv. Black Boo Stammi die resistent is tegen de Bayoudziekte, bevonden zich stoffen die de sporekieming en de groei van kiembuizen onderdrukken. Dit gold voor alle drie isolaten vanFusarium oxysporum f. sp.albedinis, die werden getoetst. In extracten van de vatbare cultivar Jihel werden de kieming en de groei niet geremd.  相似文献   
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OBJECTIVE: To assess the physiologic response to, and acute survival of, cats undergoing cardiopulmonary bypass (CPB) and to evaluate the efficacy of a commercial human pediatric oxygenator system on cats weighing less than 6 kg. STUDY DESIGN: Experimental study. ANIMALS: Six intact male cats METHODS: Cats were placed on cardiopulmonary bypass by cannulating the cranial and caudal vena cavae and the carotid artery. The pediatric CPB circuit was primed with 150 mL of a balanced crystalloid solution. Venous drainage was enhanced by a controlled, vacuum-assist system. A cross-clamp was placed on the ascending aorta and cardiac arrest was induced by antegrade infusion of a cold cardioplegia solution. After 45 minutes of arrest time, the cross-clamp was removed and the cats were weaned off bypass and decannulated. No blood products were administered. Heart rate, mean arterial pressure (MAP), central venous pressure, arterial blood gas, hematocrit (HCT), total plasma protein concentration (TP), serum electrolyte concentrations, and activated clotting time (ACT) were measured at baseline period (BL), during CPB, 60 minutes after CPB (CPB 60) and 90 minutes after CPB (CPB 90). A complete blood count (CBC), blood chemistry profile, and urinalysis were performed at BL, during CPB, and CPB 90. Cats were euthanatized after CPB 90. RESULTS: Cardiopulmonary bypass resulted in a significant (P <.05) decrease in mean HCT (18.0%) and TP (2.3 gm/dL) at CPB 90 when compared to BL (30.5% and 6.0 gm/dL, respectively). The MAP at CPB 90 (54 mm Hg) was decreased from BL (94 mm Hg). The ACT increased from a mean of 124 seconds to > 400 seconds with heparinization and was reversed to 300 seconds with protamine. Mean platelet counts decreased from BL (369,000 /microL) to CPB 90 (94,500 /microL). Mean white blood cell counts decreased from 13,200 /microL at BL to 2,200 /microL at CPB 90. Upon reperfusion, 1 cat fibrillated but was successfully defibrillated. CONCLUSIONS: Cardiopulmonary bypass was performed successfully in 6 cats weighing less than 6 kg. Acute survival to 90 minutes after CPB was achieved in all 6 cats CLINICAL RELEVANCE: The ability to perform CPB in the cat may allow intracardiac repair of various heart defects in this species.  相似文献   
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Agroforestry Systems - Complex agroforestry systems are suggested as a possible solution to reduce the effects of deforestation in the tropics while enhancing the livelihoods of local human...  相似文献   
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New Forests - Between the nineteenth and early twentieth centuries, large-scale afforestation projects were undertaken in the Swiss Prealps. The Swiss stone pine (Pinus cembra L.), an emblematic...  相似文献   
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  • 1. Most non‐insect invertebrates that occur in streams on tropical Pacific islands are diadromous; they live as juveniles and adults in streams but have larvae that migrate to the ocean to complete their development before returning to fresh water.
  • 2. The type of crossing used in the construction of roads to traverse small streams can impede upstream migration and, consequently, colonization of diadromous fauna above the stream crossing.
  • 3. A stream in the Opunohu Valley, Moorea, French Polynesia, had the same diadromous fauna of atyid shrimps, palaemonid prawns, and neritid snails occurring above and below an 8 m wide, 10 m long, bottomless culvert (i.e. an open‐bottom bridge) built to flow over natural substrates. However, no diadromous species were found upstream of two 1 m diameter, 8 m long concrete pipes used for a culverted stream crossing. The increased shear stress in the pipe and subsequent downstream erosion of the stream bed probably inhibited upstream migration.
  • 4. Modifications to culverted stream crossings, which are widely used on tropical islands, can reduce migration barriers and prevent upstream loss of diadromous stream fauna.
Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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