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61.
62.
Germplasm with shorter duration than that of the currently grown varieties is being generated to maximize productivity of irrigated rice. However, short-duration varieties often produce yields lower than the medium- and long-duration varieties. Experiments were conducted during the 1980–82 dry and wet seasons to increase productivity through the use of very early-maturing rices and the improved management of nitrogen (N) fertilizers.Results over three years showed that IR58 and IR9729-67-3 (growth duration 100 ± 5 days) yield as well as or higher than IR36 although earlier maturing. They generally had a higher productivity (kg ha–1 day–1) than IR36 (110 ± 5 days).Three years' data suggest that the improved timing of broadcast applications of urea in split doses increased grain yield comparable with the basal incorporation of slow-release sulfur-coated urea (SCU) or deep point-placement of urea supergranules (USG).Results on elite breeding lines showed that the early-maturing IR9729-67-3 produced higher protein yield ha–1 than longer duration varieties such as IR8 and IR42 in the dry season. Furthermore, contrary to earlier results, single basal incorporation of slow-release SCU increased the protein yield of rice by 53 kg ha–1 and deep point-placement of USG by 43 kg ha–1 over split application of prilled urea.  相似文献   
63.
When developing a complex, multi‐authored code, daily testing on multiple platforms and under a variety of conditions is essential. It is therefore necessary to have a regression test suite that is easily administered and configured, as well as a way to easily view and interpret the test suite results. We describe the methodology for verification of FLASH, a highly capable multiphysics scientific application code with a wide user base. The methodology uses a combination of unit and regression tests and an in‐house testing software that is optimized for operation under limited resources. Although our practical implementations do not always comply with theoretical regression‐testing research, our methodology provides a comprehensive verification of a large scientific code under resource constraints.Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Integrins exhibit reversible changes in their ability to bind ligands and these changes enable transient cell adhesion. We recently showed that leukocyte integrin CR3 (complement receptor type three, CD11b/CD18, alpha m beta 2) may be purified in a form that is either capable or incapable of binding soluble, monomeric ligand and that "inactive" CR3 may be rendered capable of binding ligand by addition of an anti-CR3 mAb known as KIM-127 (Cai and Wright, JBC. 270: 14358, 1995). Here, we demonstrate that active CR3 may be rendered inactive by treatment of immobilized receptor with EDTA. EDTA-treated CR3 failed to bind ligand even in the presence of mM Ca2+ and Mg2+, suggesting that EDTA-treatment caused a change in the receptor that is not readily reversed. EDTA-treated receptor did, however, bind ligand upon addition of KIM-127 plus Mg2+ with an affinity (17.8 +/- 4.5 nM) similar to untreated, active receptor (12.5 +/- 4.7 nM). EDTA-treated CR3 thus exhibits the properties of inactive CR3, in which the ligand binding site is cryptic but subject to exposure by KIM-127. A candidate for the cryptic ligand binding site is the I-domain, a Mg2+-binding region in the alpha chain of CR3. We found that monomeric C3bi binds directly to recombinant I-domain in a Mg(2+)-dependent fashion with an affinity of 300 +/- 113 nM. These results thus suggest that CR3 may be inactivated by removing tightly bound divalent cation from a cryptic site in CR3.  相似文献   
66.
Herpes simplex virus type 1 (HSV-1) DNA replication intermediates exist in a complex nonlinear structure that does not migrate into a pulsed-field gel. Genetic evidence suggests that the product of the UL12 gene, termed alkaline nuclease, plays a role in processing replication intermediates (R. Martinez, R. T. Sarisky, P. C. Weber, and S. K. Weller, J. Virol. 70:2075-2085, 1996). In this study we have tested the hypothesis that alkaline nuclease acts as a structure-specific resolvase. Cruciform structures generated with oligonucleotides were treated with purified alkaline nuclease; however, instead of being resolved into linear duplexes as would be expected of a resolvase activity, the artificial cruciforms were degraded. DNA replication intermediates were isolated from the well of a pulsed-field gel ("well DNA") and treated with purified HSV-1 alkaline nuclease. Although alkaline nuclease can degrade virion DNA to completion, digestion of well DNA results in a smaller-than-unit-length product that migrates as a heterogeneous smear; this product is resistant to further digestion by alkaline nuclease. The smaller-than-unit-length products are representative of the entire HSV genome, indicating that alkaline nuclease is not inhibited at specific sequences. To further probe the structure of replicating DNA, well DNA was treated with various known nucleases; our results indicate that replicating DNA apparently contains no accessible double-stranded ends but does contain nicks and gaps. Our data suggest that UL12 functions at nicks and gaps in replicating DNA to correctly repair or process the replicating genome into a form suitable for encapsidation.  相似文献   
67.
NK recognition and lysis of targets are mediated by activation receptor(s) whose effects may be over-ridden by inhibitory receptors recognizing class I MHC on the target. Incubation of normal lymphoblasts with a peptide that can bind to their class I MHC renders them sensitive to lysis by syngeneic NK cells. By binding to class I MHC, the peptide alters or masks the target structure recognized by an inhibitory NK receptor(s). This target structure is most likely an "empty" dimer of class I heavy chain and beta2m as opposed to a "full" class I trimer formed by binding of specific peptide that is recognized by CTL.  相似文献   
68.
A commercial patient dose verification system utilizing non-invasive metal oxide semiconductor field effect transistor (MOSFET) dosimeters originally designed for radiotherapy applications has been evaluated for use at diagnostic energy levels. The system features multiple dosimeters that may be used to monitor entrance or exit skin dose and intracavity doses in phantoms in real time. We have characterized both the standard MOSFET dosimeter designed for radiotherapy dose verification and a newly developed "high sensitivity" MOSFET dosimeter designed for lower dose measurements. The sensitivity, linearity, angular response, post-exposure response, and physical characteristics were evaluated. The average sensitivity (free in air, including backscatter) of the radiotherapy MOSFET dosimeters ranged from 3.55 x 10(4) mV per C kg(-1) (9.2 mV R(-1)) to 4.87 x 10(4) mV per C kg(-1) (12.6 mV R(-1)) depending on the energy of the x-ray field. The sensitivity of the "high sensitivity" MOSFET dosimeters ranged from 1.15 x 10(5) mV per C kg(-1) (29.7 mV R(-1)) to 1.38 x 10(5) mV per C kg(-1) (35.7 mV R(-1)) depending on the energy of the x-ray field. The high sensitivity dosimeters demonstrated excellent linearity at high energies (90 and 120 kVp) and acceptable linearity at lower energies (60 kVp). The angular response was significant for free-in-air exposures, as illustrated by the sensitivity differences between the two sides of the dosimeter, but was excellent for measurements within a tissue equivalent cylinder. The post-exposure drift response is a complicated but reproducible function of time. Real-time monitoring requires little if any corrections for the post-exposure drift response. The MOSFET dosimeter system brings some unique capabilities to diagnostic radiology dosimetry including small size, real-time capabilities, nondestructive measurement, good linearity, and a predictable angular response.  相似文献   
69.
The use of combined sensors and advanced algorithms using different principles can improve rate performance over a single sensor system. Combinations of sensors and more sophisticated algorithms, however, invariably increase the complexity of pacemaker programming. An automatically optimized combined minute ventilation and activity DDDR pacemaker was developed to minimize repeated sensor adjustment. The device used subthreshold (below cardiac stimulation threshold) lead impedance to detect lead configuration at implantation automatically, followed by "implant management," including setting of lead polarity and initiation of DDDR pacing. Automatic sensor adaptation was achieved by programming a "target rate histogram" based on the patient's activity level and frequency of exertion, and the rate profile optimization process matched the recorded integrated sensor response to the target rate histogram profile. In nine patients implanted with the DX2 pacemakers, the implant management gave 100% accuracy in the detection of lead polarity. Rate profile optimization automatically increased the pacing rate during exercise between discharge and 3-month follow-up (hall walk: 78 +/- 3 vs 98 +/- 3 beats/min, and maximal treadmill exercise: 89 +/- 6 vs 115 +/- 5 beats/min, P < 0.001) with a significant increase in exercise duration during maximal exercise (7.18 +/- 1 min vs 9.56 +/- 2 min, P = 0.05). The accuracy of rate profile optimization versus manual programming was assessed at 1 month, and there was no significant difference between pacing rate kinetics and maximal pacing rate between the two methods of programming. In conclusion, pacemaker automaticity can be initiated at implantation and the self-optimized rate adaptive response appeared to be comparable to that derived from a manual programming procedure, which may reduce the need to perform time consuming sensor programming.  相似文献   
70.
The paper analyzes the standard legal and methodological assurance of the quality and safety of animal food raw materials and foodstuffs (meat, meat products, fish, shellfish, crayfish and their processing products) by the parasitic purity rates according the requirements under the Russian Federation's laws "On Sanitary and Epidemiological Well-Being of the Population", "On Protection of Consumer's Rights", "On Certification of Products and Services", those of SanPiN, such as 2.3.2.560-96 "Sanitary Requirements for the Quality and Safety of Food Raw Materials and Foodstuffs" and 3.2.569-96 "Prevention of Parasitic Diseases in the Russian Federation".  相似文献   
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