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11.
Journal of Materials Science: Materials in Electronics - The octa-coordinated complexes of Sm(III) with β-diketone and nitrogen-heterocyclic bidentate auxiliary moiety were prepared and...  相似文献   
12.
Mutations in the Na-K-2Cl co-transporter NKCC2 lead to type I Bartter syndrome, a life-threatening kidney disease. We previously showed that export from the ER constitutes the limiting step in NKCC2 maturation and cell surface expression. Yet, the molecular mechanisms involved in this process remain obscure. Here, we report the identification of chaperone stress 70 protein (STCH) and the stress-inducible heat shock protein 70 (Hsp70), as two novel binding partners of the ER-resident form of NKCC2. STCH knock-down increased total NKCC2 expression whereas Hsp70 knock-down or its inhibition by YM-01 had the opposite effect. Accordingly, overexpressing of STCH and Hsp70 exerted opposite actions on total protein abundance of NKCC2 and its folding mutants. Cycloheximide chase assay showed that in cells over-expressing STCH, NKCC2 stability and maturation are heavily impaired. In contrast to STCH, Hsp70 co-expression increased NKCC2 maturation. Interestingly, treatment by protein degradation inhibitors revealed that in addition to the proteasome, the ER associated degradation (ERAD) of NKCC2 mediated by STCH, involves also the ER-to-lysosome-associated degradation pathway. In summary, our data are consistent with STCH and Hsp70 having differential and antagonistic effects with regard to NKCC2 biogenesis. These findings may have an impact on our understanding and potential treatment of diseases related to aberrant NKCC2 trafficking and expression.  相似文献   
13.
14.
Most images may not be sharp and clear due to various reasons like noise interference and is said to be in a blurred condition. Image de-blurring is fundamental in making pictures sharp and useful. Normally, along with the input blurred image, Point Spread Function (PSF) of the original image is required for the process of restoration and de-blurring. In this paper, we introduce a technique for image restoration by Richardson–Lucy algorithm where the optimised PSF is generated by the use of Genetic Algorithm (GA). Use of optimised PSF ensures that our proposed technique does not need the original image for the de-blurring purpose and can be greatly beneficial in the real time scenario cases. The dataset used for the evaluation of the proposed technique are real 3D images and the evaluation metrics used are peak signal-to-noise ratio (PSNR), Second-Derivative like Measure of Enhancement (SDME) and mean squared error (MSE). The technique is compared with existing techniques such as de-convolution method, regularisation filter, Wiener filter and Richardson–Lucy algorithm. From the results, we can observe that our proposed technique has achieved higher PSNR and SDME values and lower MSE values when compared with other techniques. We have achieved average PSNR of 70·94, SDME of 71·46 and MSE of 0·0063. The values obtained show the superior performance of the proposed technique.  相似文献   
15.
Urbach energy of valence band tails and mid-gap defect densities are important parameters for determining the performance of amorphous silicon (a-Si:H) devices. In this paper, we examine a technique which allows one to determine these parameters in device structures, as opposed to in films. The technique consists of measuring sub-gap quantum efficiency as a function of reverse bias and photon wavelength. We show that there is a distinction between the response of tail states and mid-gap states to the application of reverse bias, and that by analyzing these differences, one can locate the energies of the mid-gap states in the device. The technique gives an accurate measurement of Urbach edge of tail states, even on textured substrates, but only estimates mid-gap states within a factor of 2.  相似文献   
16.
The combinatorial design approach to automatic test generation   总被引:1,自引:0,他引:1  
The combinatorial design method substantially reduces testing costs. The authors describe an application in which the method reduced test plan development from one month to less than a week. In several experiments, the method demonstrated good code coverage and fault detection ability  相似文献   
17.
Cot death (sudden infant death syndrome) is one of the most common causes of death in the first year of life. Four cases with a pathological fear of cot death are presented. All the patients were depressed and in 2 cases the fear of cot death had an obsessional quality. In all cases there were complications during pregnancy (miscarriage, threatened abortion, recurrent vomiting in last trimester). In 1 case, the patient knew 3 mothers who had suffered cot deaths; in another, the infant was gravely ill in the neonatal period. Pathological fear of cot death can be recognised by the presence of two central features - overvigilance and excessive nocturnal checking of the baby's breathing. Therapeutic interventions are discussed.  相似文献   
18.
Some graphical aids for deciding when to stop testing software   总被引:1,自引:0,他引:1  
It is noted that the developers of large software systems must decide how much software should be tested before releasing it. An explicit tradeoff between the costs of testing and releasing is considered. The former may include the opportunity cost of continued testing, and the latter may include the cost of customer dissatisfaction and of fixing faults found in the field. Exact stopping rules were obtained by Dalal and Mallows (J. Amer., Statist. Assoc., vol.83, p.872, 1988), under the assumption that the distribution of the fault finding rate is known. Here, two important variants where the fault finding distribution is not completely known are considered. They are (i) the distribution is exponential with unknown mean and (ii) the distribution is locally exponential with the rate changing smoothly over time. New procedures for both cases are presented. In case (i) it is shown how to incorporate information from related projects and subjective inputs. Several novel graphical procedures which are easy to implement are proposed, and these are illustrated for data from a large telecommunications software system  相似文献   
19.
Experimental results on thin films of the new material GexC1−x, deposited by a unique dual plasma hollow cathode sputtering technique are presented here. The (Ge, C) system is extremely promising since the addition of C to Ge has reduced the lattice dimensions enough to allow a lattice match to silicon, while increasing the bandgap close to that of c-Si. The most important contribution of this work shows that by the non-equilibrium growth conditions present using the hollow cathode technique, one can grow Group IV materials which cannot otherwise be grown using normal CVD or MBE processes. The sputtering is accomplished by igniting a DC plasma of the Ar and H2 gases which are fed through Ge and C nozzles, cylindrical tubes 30 mm in length with an 8 mm OD and a 3 mm ID.  相似文献   
20.
A genetic system in wheat is described in which F1 produced by crossing a drought tolerant cultivar C306 and high yielding cultivar WL711 exhibits leaf necrosis leading to the death of the plant. The mechanism underlying hybrid necrosis is not yet known. The hybrid exhibited a higher level of superoxide anion compared to the healthy leaves of parents at similar developmental stages. This increase in superoxide generation preceded necrotic lesion formation and displayed a gradient from the leaf tip to base. The leaf tip where necrotic lesions make their first appearance exhibited a higher level of superoxide compared to the base. Superoxide anion thus appears to play a vital role in necrosis of leaves in F1 hybrid. This genetic system can be a model system for understanding cell death in higher plants.  相似文献   
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