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161.
Recently, the FokI polymorphism (rs2228570) in the vitamin D receptor gene (VDR) and conventional risk factors were associated with spine disorders in the Italian population, but without gender analysis. Two-hundred and sixty-seven patients (149 males, 118 females) with lumbar spine disorders were assessed by magnetic resonance imaging (MRI) and 254 (127 males, 127 females) asymptomatic controls were enrolled. The exposure to putative risk factors was evaluated and FokI polymorphism was detected by PCR-restriction fragment length polymorphism (PCR-RFLP). An association between lumbar spine pathologies and higher than average age; overweight; family history; lower leisure physical activity; smoking habit; higher number of hours/day exposure to vibration and more sedentary or intense physical job demand was observed in male patients. In contrast, in females, only higher age, overweight, family history and lower leisure physical activity were risk factors. FF genotype was a 2-fold risk factor to develop discopathies and/or osteochondrosis concomitant with disc herniation for both gender patients, while heterozygous Ff was protective for females only. In males only ff genotype was protective for discopathies and/or osteochondrosis and F allele was a 2-fold risk factor for hernia; discopathies; discopathies and/or osteochondrosis. Sex-related differences in voluntary behaviors, exposure to environmental risks and genetic background could be crucial for a gender-differentiated management of patients with spine disorders.  相似文献   
162.
The paper describes the application of X-ray photoelectron spectroscopy (XPS) based method to quantify changes in the electric dipole formed at the metal/dielectric interface following heat treatments of metal–oxide–semiconductor (MOS) stack in different environments. The presented results on Me (Me = Au, Ni)/dielectric (dielectric = HfO2, LaAlO3) evidence the oxygen vacancies generated in dielectric contribute to the effective work function changes.  相似文献   
163.
Support for modeling relationships in object-oriented databases   总被引:2,自引:0,他引:2  
Modeling real-world applications typically consists of two parts: the representations of entities of interest, and the representations of relationships among the entities. Object-oriented data models support the first task. This paper argues through examples that the second modeling task is not well supported in current object-oriented database systems. An extended object-oriented data model that facilitates both modeling tasks is developed. This extension provides support for both the representation of complex relationships among entities and their manipulations (queries, updates). A prototype implemented on the ONTOS database management system is briefly described.  相似文献   
164.
A MIMD based multiprocessor architecture for real-time video processing applications consisting of identical bus connected processing elements has been developed. Each processing element contains a RISC processor for controlling and data-dependent tasks and a Low Level Coprocessor for fast processing of convolution-type video processing tasks. To achieve efficient parallel processing of video input signals, the architecture supports independent processing of overlapping image segments. Running at a clock rate of 40 MHz, a single processing element provides a peak performance of 640 Mega arithmetic operations per second (MOPS). For the real-time processing of basic video processing tasks like 3×3 FIR-filter, 8×8 2D-DCT and motion estimation, a single processing element provides a sufficient computational rate for video signals with Common Intermediate Format (CIF) at a frame rate up to 30 Hz. For hybrid source coding of CIF video signals at a frame rate of 30 Hz a multiprocessor system consisting of six processing elements is required. A linear speedup of the multiprocessor system compared to a single processing element is achieved. A VLSI implementation of a processing element in 0.8 µm CMOS technology is under development.  相似文献   
165.
166.
Development of gamma irradiation preservation of ready-to-eat, commercially prepared fish cutlet and improvement of microbiological quality were studied. Studies on the shelf life extension by a combination of irradiation and ascorbic acid treatments of fish cutlets prepared at the laboratory and commercial scale have also been conducted. Cutlets prepared at the laboratory scale according to selected formulation and irradiated at a dose of 5 kGy could extend the shelf life up to 5 weeks at room temperature. In commercially prepared fish cutlets, maximum shelf life extension observed was 14 days for samples treated with 5 kGy of irradiation and stored at ambient temperature on the basis of combined microbiological, chemical, and organoleptic evaluation. The microbiological quality of the commercially prepared fish cutlets revealed the unhygienic conditions of the place where the fish was prepared and the unhygienic storage conditions and temperatures. As a result, the chemical and irradiation treatments were not effective in extending the shelf life of the cutlets under the storage condition used in this study compared with that of the laboratory scale-prepared cutlets.  相似文献   
167.
The work describes the preparation and physical‐mechanical characterization of unidirectional CFRP panels manufactured by an electron beam curing technique. Delamination fracture toughness in Mode I and II is investigated in order to evaluate the influence of fiber–matrix adhesion strength, matrix toughness and matrix crosslinking density as determined by the radiation curing process. A matrix system comprising a DGEBA epoxy monomer and an initiator of cationic polymerization have been used, with one batch of resin mixed with a PES monomer in order to enhance matrix toughness. Curing was achieved with a pulsed 10 MeV Electron Beam accelerator. Thermally cured composite systems have also been manufactured and tested for comparison. Results from double cantilever beam and end notched flexure delamination tests have been analyzed and correlated with results from short beam shear, dynamic mechanical thermal analysis tests and SEM micrographs of delaminated surfaces. POLYM. COMPOS., 35:1529–1542, 2014. © 2013 Society of Plastics Engineers  相似文献   
168.
169.
Pattern Analysis and Applications - The automated identification of brain structure in Magnetic Resonance Imaging is very important both in neuroscience research and as a possible clinical...  相似文献   
170.
The objective of this study was to investigate the utilization of Caralluma fimbriata an edible succulent cactus as natural antioxidants for retarding acrylamide formation, lipid oxidation, and the degradation of bioactive compounds in French fries due to frying at 190°C. The fresh Caralluma fimbriata extract exhibited the highest phenolic content of 96.4 ± 0.1 mg gallic acid equivalent/g when the raw potato extract showed significantly 27.4 ± 0.3 mg GAE/g before frying. The Caralluma fimbriata extract had the higher flavonoid content of 54.4 ± 0.1 mg of Quercetin equivalent/g, while the raw potato had 38.8 ± 0.2 mg of Quercetin equivalent/g. The total flavonols and flavanols in Caralluma fimbriata were signi?cantly high, and those were found to be 27.6 ±0.8 mg Quercetin Equivalent/g and 19.1 ±0.6 mg Catechin equivalent/g, respectively, and, eventually, higher than potato extract. These bioactive compounds are easily degraded due to frying at high temperatures. The Caralluma fimbriata extract retards the formation of acrylamide precursors in potato, primary and secondary oxidation products, and the degradation of polyphenols after the immersion treatment. The Caralluma fimbriata extract was found to be more effective against acrylamide level (42.5 μg/kg) in French fries. The Caralluma fimbriata treated sample exhibited comparatively better oxidative stability during holding time with highest overall acceptability than the sample treated with butylated hydroxyanisole, distilled water (control) and raw potato (without treatment). The results will provide scientific basis in the use of Caralluma fimbriata as natural antioxidant against acrylamide formation and the oxidative deterioration of bioactive compounds.  相似文献   
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