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1.
A three-factor factorial experiment was performed to assess the efficiency of lipid extraction from the back of human volunteers. Chloroform-methanol (2:1 v/v) proved substantially superior to acetone or diethyl ether. The latter two solvents were also significantly more efficient than n-hexane. The implication of the findings is discussed with regard to the isolation and characterization of fungistatic and bacteriostatic agents on the surface of the skin.  相似文献   
2.
In this note, we prove that the complexity of scattering in an oriented ring of p processors is (p - 1) (β + Lτ) where L is the length of the messages, β the communication startup, and τ the elemental propagation time.  相似文献   
3.
Performing reduction operations with distributed memory machines whose interconnection networks are reconfigurable is considered. The focus is on machines whose interconnection graph can be configured as any graph of maximum degree d. The best way of interconnecting the p processors as a function of p,d and some problem- and machine-dependent parameters that characterize the ratio communication/arithmetic for the reduction operation are discussed. Experiments on transputer-based networks are in good accordance with the theoretical results  相似文献   
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5.
We report the bulk growth of single-crystal CdZnTe and characterization of material associated with large-area wafers produced from the CdZnTe ingots. Our experimental vertical gradient freeze set-up enables accurate detection of the beginning and end of the crystallization step by careful monitoring of the thermal cycle. Single crystal, (111)-oriented ingots with a diameter of 80 mm were routinely obtained without grain boundary or twin. The size of the CdZnTe ingots was extended to 115 mm in diameter, enabling production of large-dimension substrates suitable for infrared focal-plane arrays with megapixel-resolution. Crystal quality was investigated by double-crystal x-ray rocking curve mapping and by chemical revelation of etch pits. Typical mean values for the rocking curve full width at half maximum were in the range 20–40 arcs. Evaluation of etch pit density on the (111)Te face furnished values in the low 104/cm2.  相似文献   
6.
Human Fasciola hepatica infection is usually discovered either early, during the acute (invasive) phase, or in the advanced phase, which is characterized by biliary complications. We report a case of liver distomatosis with nodular intra-hepatic lesions in a 58-year-old woman. Radiological investigations showed 3 nodular lesions in the VII segment, which were difficult to distinguish from liver metastases or liver abscesses. Distomatosis serology was positive with passive hemagglutination. After a 5-day treatment with praziquantel, clinical symptoms resolved quickly while serological tests became negative. Radiological images slowly decreased to a calcified scar at 13 months. No side-effects were noted. Praziquantel, whose efficacy in the common presentations of liver distomatosis has recently been demonstrated, also seems effective and well tolerated in case of nodular intra-hepatic lesions.  相似文献   
7.
The liver tissue mRNA expression of protooncogenes c-fos, c-myc, c-Ha-ras, c-met and c-erb B1, and TGF alpha and TGF beta genes is sequentially and temporarily increased in the early stages after partial hepatectomy, ischaemia or other mitogenic stimuli. These gene expressions were studied in 38 samples of liver tissue from 24 patients who underwent orthotopic liver transplantation, at different evolution stages. Eleven samples were obtained from surgical liver biopsies before graft implantation at day 0 (Group A), 14 samples from percutaneous liver biopsies during the post-operative period from day 9 to day 48 (Group B) and 13 samples in the long-term follow-up period from day 102 to day 1,382 (Group C). Gene expression was studied using 32P-labeled cDNA and oligonucleotidic probe hybridization in slot blots. A GAPD gene was used as a control gene. All expression values of protooncogenes were related to those of the GAPD gene. After cold ischaema, the relative gene expression (quantity of specific mRNA/quantity of GAPD mRNA ratio) tended to diminish in most cases. The relative expressions of c-fos, c-myc, c-Ha-ras, c-met and TGF alpha gene were correlated at day 0. During and after the liver transplantation, an overexpression of c-fos, c-myc, c-Ha-ras, c-met and TGF alpha was observed in different pathological conditions such as cold ischaemia and conservation injury, acute rejection, and cytomegalovirus infection. In three cases the relative expression values of c-fos, c-myc and c-Ha-ras increased over long-term follow-up without any associated acute pathology. These results suggest the necessity of an intercellular mediation--by means of graft reperfusion--in induction of hepatocyte proliferation and regeneration of the transplanted liver.  相似文献   
8.
Pattern Analysis and Applications - In this work, we propose a new formulation of the objects modeling combining geometry and appearance; it is useful for detection and recognition. The object...  相似文献   
9.
License Plate Recognition (LPR) is mainly regarded as a solved problem. However, robust solutions able to face real-world scenarios still need to be proposed. Country-specific systems are mostly, designed, which can (artificially) reach high-level recognition rates. This option, however, strictly limits their applicability. In this paper, we propose an approach that can deal with various national plates. There are three main areas of novelty. First, the Optical Character Recognition (OCR) is managed by a hybrid strategy, combining statistical and structural algorithms. Secondly, an efficient probabilistic edit distance is proposed for providing an explicit video-based LPR. Last but not least, cognitive loops are introduced at critical stages of the algorithm. These feedback steps take advantage of the context modeling to increase the overall system performances, and overcome the inextricable parameter settings of the low-level processing. The system performances have been tested in more than 1200 static images with difficult illumination conditions and complex backgrounds, as well as in six different videos containing 525 moving vehicles. The evaluations prove our system to be very competitive among the non-country specific approaches.  相似文献   
10.
Experimental and theoretical analysis of the origin of porosity in electron-beam (EB) welding is detailed. The experiments are run with several surface treatments and reasonable welding parameters. The plate faces are characterized before welding with a number of methods, such as scanning electron microscope observation, X-ray photoemission spectroscopy (XPS) and, more significantly, secondary ion mass spectroscopy (SIMS) analysis, elastic-recoil detection analysis (ERDA) for hydrogen analysis, and surface roughness measurement. After welding, pores are sought with X-ray detection, phased-array ultrasonic (US) detection, and destructive control. An original comparison between ERDA and refined SIMS measurements allows a quantitative evaluation of surface pollution with hydrogen, oxygen, and carbon. The theoretical analysis is based on the literature concept that the cavities are nucleated from the adjacent plate faces in the solid state, just before melting. A less classical development is proposed in term of the evolution of bubbles in the weld pool. Once in the liquid, the cavities become bubbles. Their radius oscillates, according to Rayleigh-Plesset equations of bubbles, due to temperature and pressure driving forces. Solidification freezes them as they are, thus, forming pores. The extreme values of the oscillation give a good idea of the range of the size of pores in the weld joint, as the comparison between experiments and prediction states. A criterion of surface cleanliness is set, relating the surface pollution and the surface roughness. Above the criterion, the bubbles remain small during their oscillation. Below the criterion they tend to grow large. All the degraded-surface treatments are in dirty situation (large pores), and the reference surface treatment lies around the criterion for cleanliness.  相似文献   
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