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71.
This paper reports the associated malformations and the clinical findings that were observed in 417 cytogenetically confirmed Down Syndrome patients. Among them congenital heart defects have occurred more frequently [75; 17.98%] than osteoarticular malformations [23; 5.52]; eye anomalies [22; 5.27%]; and gastroenterological malformations [n 16; 3.84%]. With regard to prognosis and treatment appropriate counselling has been given to Down Syndrome patients and their families.  相似文献   
72.
Translocational pausing is a mechanism used by certain specialized secretory proteins whereby discrete domains of a nascent chain destined for the endoplasmic reticulum lumen are transiently exposed to the cytosol. Proteoliposomes reconstituted from total endoplasmic reticulum proteins properly assemble translocationally paused intermediates. The capacity of the translocon to correctly pause the nascent chain is dependent on a glycoprotein fraction whose active component is TRAM. In the absence of TRAM, the normally sealed ribosome-membrane junction still opens in response to a pause transfer sequence. However, nascent chain domains that are not exposed to the cytosol in the presence of TRAM are so exposed in its absence. Thus, TRAM regulates which domains of the nascent chain are visible to the cytosol during a translocational pause.  相似文献   
73.
This paper illustrates the usefulness of an attributed prefix linear intermediate representation for compiler code generation. In separating the machine-independent and machine-dependent aspects of a compiler, we discuss the advantages and disadvantages of an attributed linear intermediate representation with respect to tree-structured intermediate representations. Some of these issues are relevant to fundamental questions of compiler structure with particular emphasis on retargetability. We discuss our implementation experience using this linear intermediate representation with a table-driven code generation scheme for a variety of target architectures.  相似文献   
74.
Summary Peephole optimization when integrated with automatic code generation into a uniform framework has significant advantages in the specification and implementation of efficient compiler back-ends. Attribute grammars provide a framework for expression of machine-specific code optimizations. We present a grammar-driven peephole optimization algorithm that is particularly well suited to attributed-parsing code generators. Integration via semantic attributes corrects interrelated phase-ordering problems and produces a faster and smaller compiler back-end.  相似文献   
75.
1. Urinary bladder smooth muscle is enriched with muscarinic receptors, the majority of which are of the M2 subtype whereas the remaining minority belong to the M3 subtype. The objective of the present study was to assess the functional role of M2 and M3 receptors in the urinary bladder of rat in vitro and in vivo by use of key discriminatory antagonists. 2. In the isolated bladder of rat, (+)-cis-dioxolane produced concentration-dependent contractions (pEC50 = 6.3) which were unaffected by tetrodotoxin (0.1 microM). These contractions were antagonized by muscarinic antagonists with the following rank order of affinity (pA2) estimates: atropine (9.1) > 4-diphenyl acetoxy-methyl piperidine methiodide (4-DAMP) (8.9) > darifenacin (8.5) > para fluoro hexahydrosiladifenidol (p-F-HHSiD) (7.4) > pirenzepine (6.8) > methoctramine (5.9). These pA2 estimates correlated most favourably (r = 0.99, P < 0.001) with the binding affinity (pKi) estimates of these compounds at human recombinant muscarinic m3 receptors expressed in Chinese hamster ovary cells, suggesting that the receptor mediating the direct contractile responses to (+)-cis-dioxolane equates with the pharmacologically defined M3 receptor. 3. As M2 receptors in smooth muscle are negatively coupled to adenylyl cyclase, we sought to determine whether a functional role of M2 receptors could be unmasked under conditions of elevated adenylyl cyclase activity (i.e., isoprenaline-induced relaxation of KCl pre-contracted tissues). Muscarinic M3 receptors were preferentially alkylated by exposing tissues to 4-DAMP mustard (40 nM, 1 h) in the presence of methoctramine (0.3 microM) to protect M2 receptors. Under these conditions, (+)-cis-dioxolane produced concentration-dependent reversal (re-contraction) of isoprenaline-induced relaxation (pEC50 = 5.8) but had marginal effects on pinacidil-induced, adenosine 3':5'-cyclic monophosphate (cyclic AMP)-independent, relaxation. The re-contractions were antagonized by methoctramine and darifenacin, yielding pA2 estimates of 6.8 and 7.6, respectively. These values are intermediate between those expected for these compounds at M2 and M3 receptors and were consistent with the involvement of both of these subtypes. 4. In urethane-anaesthetized rats, the cholinergic component (approximately 55%) of volume-induced bladder contractions was inhibited by muscarinic antagonists with the following rank order of potency (ID35%inh, nmol kg-1, i.v.): 4-DAMP (8.1) > atropine (20.7) > methoctramine (119.9) > darifenacin (283.3) > pirenzepine (369.1) > p-F-HHSiD (1053.8). These potency estimates correlated most favourably (r = 0.89, P = 0.04) with the pKi estimates of these compounds at human recombinant muscarinic m2 receptors. This is consistent with a major contribution of M2 receptors in the generation of volume-induced bladder contractions, although the modest potency of darifenacin does not exclude a role of M3 receptors. Pretreatment with propranolol (1 mg kg-1, i.v.) increased the ID35%inh of methoctramine significantly from 95.9 to 404.5 nmol kg-1 but had no significant effects on the inhibitory responses to darifenacin. These data suggest an obligatory role of beta-adrenoceptors in M2 receptor-mediated bladder contractions in vivo. 5. The findings of the present study suggest that both M2 and M3 receptors can cause contraction of the rat bladder in vitro and may also mediate reflex bladder contractions in vivo. It is proposed that muscarinic M3 receptor activation primarily causes direct contraction of the detrusor whereas M2 receptor activation can contract the bladder indirectly by reversing sympathetically (i.e. beta-adrenoceptor)-mediated relaxation. This dual mechanism may allow the parasympathetic nervous system, which is activated during voiding, to cause more efficient and complete emptying of the bladder.  相似文献   
76.
Video streaming is considered as one of the best compelling sources of information for several applications ranging from vehicular technology, security systems, biomedical systems to aerospace applications. Video streaming using wireless network is quite challenging and a lot of research is in progress. In this paper, design and development of a low-cost real-time wireless video streaming mote is proposed which is an outcome of a funded project. Three different variants of the proposed system are designed, tested and their performances are evaluated. The first prototype uses an Arduino YUN board, second prototype uses a Raspberry PI board and the third prototype uses an Arducam ESP8266 Uno Module. The proposed wireless video streaming mote is aimed at moving around an area under surveillance, gathering images and transferring the same to control station. The proposed system has potential applications including assistance to vehicle drivers during reversing, parking, autonomous driving of the vehicles, driving vehicles using mobile application etc. The proposed system designed has a myriad of real-time applications for domestic requirements with social cause too.  相似文献   
77.

In the present paper, a new trigonometric two-variable shear deformation beam nonlocal strain gradient theory is developed and applied to investigate the combined effects of nonlocal stress and strain gradient on the bending, buckling and free vibration analysis of nanobeams. The model introduces a nonlocal stress field parameter and a length scale parameter to capture the size effect. The governing equations derived are solved employing finite element method using a 3-nodes beam element, developed for this purpose. The predictive capability of the proposed model is shown through illustrative examples for bending, buckling and free vibration of nanobeams. Comparisons with other higher-order shear deformation beam theory are also performed to validate its numerical implementation and assess its accuracy within the nonlocal context.

  相似文献   
78.
The single crystal of (tri) glycine barium chloride, a semiorganic crystal has been grown from an aqueous solution by slow evaporation technique at room temperature. Glycine and barium chloride were used in molar ratio of 3:1 for synthesis. Good optical quality single crystal of size 18 × 10 × 5 mm3 was harvested in a period of 5 weeks (35 days) at pH value 5. The lattice parameters have been measured by single crystal XRD study. The crystalline nature has been confirmed by powder XRD study. Fourier transform infrared spectroscopy study confirmed the presence of functional groups in grown crystal. Transmission spectrum has been recorded and the cut-off wavelength has been determined as 234 nm. Also optical constants like band gap, refractive index, reflectance, extinction coefficient and electric susceptibility were determined from UV–Vis-NIR spectrum. The thermal behavior of the crystal was investigated by TG–DTA analysis, which reveals that crystal has thermally stable up to 169 °C. Non-linear optical property of the grown crystal has been confirmed using the Kurtz and Perry powder technique and result was compared with KDP. The dielectric behavior of the sample was analyzed with various frequencies at different temperatures. The photoconducting nature of the crystal was analyzed by photoconductivity study.  相似文献   
79.
We consider the problem of finding meaningful correspondences between 3D models that are related but not necessarily very similar. When the shapes are quite different, a point‐to‐point map is not always appropriate, so our focus in this paper is a method to build a set of correspondences between shape regions or parts. The proposed approach exploits a variety of feature functions on the shapes and makes use of the key observation that points in matching parts have similar ranks in the sorting of the corresponding feature values. Our algorithm proceeds in two steps. We first build an affinity matrix between points on the two shapes, based on feature rank similarity over many feature functions. We then define a notion of stability of a pair of regions, with respect to this affinity matrix, obtained as a fixed point of a nonlinear operator. Our method yields a family of corresponding maximally stable regions between the two shapes that can be used to define shape parts. We observe that this is an instance of the biclustering problem and that it is related to solving a constrained maximal eigenvalue problem. We provide an algorithm to solve this problem that mimics the power method. We show the robustness of its output to noisy input features as well its convergence properties. The obtained part correspondences are shown to be almost perfect matches in the isometric case, and also semantically appropriate even in non‐isometric cases. We provide numerous examples and applications of this technique, for example to sharpening correspondences in traditional shape matching algorithms.  相似文献   
80.
While nanoparticle dispersion is necessary to achieve optimal properties, it has long been recognized as a major technological hurdle for polymer nanocomposites. Here, a systematic study incorporated carbon nanotubes (CNTs) in polycaprolactone (PCL) using a multi‐stage sonication process, with Stage 1 sonication of CNT/solvent followed by Stage 2 sonication of the pre‐processed CNT/solvent with the dissolved polymer. Conventional dispersion characterization techniques were complemented with analysis of the shear‐induced crystallization (SIC) behavior of the semicrystalline nanocomposite, which was found to be particularly sensitive to the state of nanoparticle dispersion. While Stage 1 sonication was found to have a pronounced effect on the nanoparticle dispersion as characterized via SIC and thermal characterization, the impact of Stage 2 sonication on the level of nanoparticle dispersion was much smaller. Such results demonstrate the utility of characterization of the shear‐induced crystallization behavior as a means to analyze nanoparticle dispersion in semicrystalline polymer nanocomposites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44681.  相似文献   
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