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81.
Skinless, deboned chicken breast fillets were deep fat fried (190 °C) with and without a batter and breading coating system for up to 6 min (internal temp 70 °C). Non-coated samples show surface muscle fiber splitting as soon as placed in oil. As time progressed, the depth of damage increased. Shear force and work to shear increased significantly as a dense hard crust layer was forming. By the end, fillets lost about 1/3 of their weight and had a dark, dry, brittle crust. Frying with coating protected the meat inside and no major damages to muscle fibers were observed. Shear force also increased but the values were about half of what was observed in non-coated products, meaning that the meat inside was protected. Coated products became progressively golden brown (increased a* and b*, decreased L*) while the crust adhered well to the product. After frying, the products showed a small gain in weight which was the result of no structural shrinkage and absorption of a small amount of oil.  相似文献   
82.
A model for crosstalk in three-axial induction magnetometers has been developed theoretically and verified experimentally. The effect of crosstalk on the magnetometer accuracy has been analyzed. It has been found that the inevitable crosstalk in the transverse coils has two components: one due to the applied magnetic flux and the other due to the secondary flux produced by the electric current in the longitudinal coil. The first component has a constant magnitude. The phase of the second component, relative to the first one, is nearly 180° at low frequencies, 90° at resonance, and 0° at high frequencies. Its magnitude approaches zero at low frequencies, has the maximum at resonance, and then drops off by a factor equal to the coils' quality factor and approaches the first component value. As a result, the crosstalk due to the applied flux is dominant at low frequencies. At a frequency just below the resonance, the crosstalk is very low, if no magnetic feedback is applied. Just above the resonance, the crosstalk reaches the maximum because of the rapid increase in the secondary flux. Applying a strong enough magnetic feedback nearly flattens the crosstalk amplitude response. However, an undesirable effect of the feedback is that it significantly increases the minimum crosstalk value. A very low crosstalk at a single frequency can be beneficial for magnetometers tuned to a narrow frequency band. It can also be beneficial for wide-band magnetometers to measure their mechanical orthogonality with a minimum effect of crosstalk.  相似文献   
83.
The Israel National Cancer Registry reported in 2001 that cancer incidence rates in the Haifa area are roughly 20% above the national average. Since Haifa has been the major industrial center in Israel since 1930, concern has been raised that the elevated cancer rates may be associated with historically high air pollution levels. This work tests whether persistent spatial patterns of metrics of chronic exposure to air pollutants are associated with the observed patterns of cancer incidence rates. Risk metrics of chronic exposure to PM10, emitted both by industry and traffic, and to SO2, a marker of industrial emissions, was developed. Ward-based maps of standardized incidence rates of three prevalent cancers: Non-Hodgkin's lymphoma, lung cancer and bladder cancer were also produced. Global clustering tests were employed to filter out those cancers that show sufficiently random spatial distribution to have a nil probability of being related to the spatial non-random risk maps. A Bayesian method was employed to assess possible associations between the morbidity and risk patterns, accounting for the ward-based socioeconomic status ranking. Lung cancer in males and bladder cancer in both genders showed non-random spatial patterns. No significant associations between the SO2-based risk maps and any of the cancers were found. Lung cancer in males was found to be associated with PM10, with the relative risk associated with an increase of 1 μg/m3 of PM10 being 12%. Special consideration of wards with expected rates < 1 improved the results by decreasing the variance of the spatially correlated residual log-relative risk.  相似文献   
84.
BACKGROUND: The aim was to analyse patterns of failure or symptom recurrence after primary sympathectomy for palmar or axillary hyperhidrosis, and to carry out tactical problem-solving for resympathectomy and review the operative findings. METHODS: Over a 2-year period, 20 patients (six men and 14 women) underwent resympathectomy for palmar hyperhidrosis (13 patients, 20 sides) or axillary hyperhidrosis (seven patients, ten sides). T2-3 sympathectomy for palmar hyperhidrosis or T4-5 sympathectomy for axillary hyperhidrosis was performed during the repeat procedure. Criteria for evaluation by means of patient questionnaire included good (more than 80 per cent), fair (50-80 per cent) and poor (less than 50 per cent) improvement. RESULTS: Operative findings included inadequate sympathectomy on 19 sides, nerve regeneration on eight sides and no evidence of previous sympathectomy on three sides. One patient had Kuntz fibre in addition to inadequate sympathectomy. In the palmar hyperhidrosis group, good results were obtained in all 13 patients on all 20 sides after resympathectomy. In the axillary hyperhidrosis group, six of seven patients, or eight of ten sides, showed good results after resympathectomy. CONCLUSION: The main cause of primary sympathectomy failure was inadequate surgery, and recurrence of palmar or axillary hyperhidrosis was seldom caused by nerve regeneration. The key factor for preventing failed sympathectomy or recurrent palmar or axillary hyperhidrosis is a first-time sympathectomy that is both accurate and adequate. Most patients with recurrent symptoms can be cured by resympathectomy.  相似文献   
85.
We have detected a leucine zipper-like motif in the ectodomain of the Sendai virus fusion protein (aa 269-307) which is extremely conserved in the family of Sendai viruses. To find a possible role for this motif, we synthesized SV-269, a 39 amino acid peptide corresponding to this domain, and a mutant peptide, MuSV-269, with an amino acid pair interchanged their positions. The peptides were labeled with fluorescent probes at their N-terminal amino acid and functionally and structurally characterized. The data show that SV-269, but not MuSV-269, specifically binds Sendai virus. Expectedly, SV-269 is more active than the mutant MuSV-269 in inhibiting Sendai virus-mediated hemolysis. Fluorescence studies reveal that SV-269 assembles in aqueous solution, binds to zwitterionic PC and negatively-charged PS/PC vesicles, and assembles therein. Although MuSV-269 similarly binds to both types of vesicles, it only slightly assembles in solution and not at all in membranes. Moreover, SV-269, but not MuSV-269, coassembles with the biologically-active heptad repeats SV-150 and SV-473 (Rapaport et al. , 1995) in solution as revealed by fluorescence and circular dichroism (CD) spectroscopy, and with SV-150 within negatively-charged PS/PC and zwitterionic PC vesicles. Despite these differences, both SV-269 and MuSV-269 adopt similar secondary structures in 40% TFE and 1% SDS as revealed by CD spectroscopy, and disrupt the packing of the lipid bilayers to the same extent, as shown by the dissipation of diffusion potential. The role of this leucine zipper motif is discussed in terms of the assembly of the Sendai virus fusion protein in solution and within membranes. Since most of the heptadic leucines are also conserved in the corresponding domains of other paramyxoviruses such as rinderpest, measles, SV5, and parainfluenza, it may indicate a similar role of this domain in these viruses as well.  相似文献   
86.
We examined the long term results of vertical banded gastroplasty 3-10 years after operation. They were assessed by weight lost, incidence and severity of untoward effects and improvement in diet and in quality of life in 75 of 122 who had had the operation. Average weight lost was 28.5 +/- 14.9 kg (p < 0.001) in 5 years and 58.6 +/- 30.4% of excess weight, which brought patients to within 32 +/- 25.2% of ideal weight. According to these measures, in 63-76% the operation had been successful in causing weight loss. The 2 criteria for successful weight loss were loss of more than 50% of weight in excess of ideal body weight and residual body weight less than 50% greater than ideal body weight. There was a greater risk of failure in unmarried subjects older than 45 (odds ratio for not losing weight was 6; in those weighing more than 120 kg it was 9). We saw evidence of this mostly 4 years after operation (odds ratio 11). The degree of success in weight loss was correlated with texture of food (softness) preferred and length of operation. Of those interviewed, only 65% were satisfied with their results. The greatest improvement in quality of life measurements was in physical activity, perception of health, and frequency of feeling depressed. Side-effects were vomiting, reflux and fatigue. Only 34.7% were able to digest solid foods, so that subjects are at risk for nutritional deficiencies.  相似文献   
87.
We study functions with multiple output values, and use active sampling to identify an example for each of the possible output values. Our results for this setting include: (1) Efficient active sampling algorithms for simple geometric concepts, such as intervals on a line and axis parallel boxes. (2) A characterization for the case of binary output value in a transductive setting. (3) An analysis of active sampling with uniform distribution in the plane. (4) An efficient algorithm for the Boolean hypercube when each output value is a monomial. Editors: Hans Ulrich Simon, Gabor Lugosi, Avrim Blum. A preliminary version of this work was presented in the 19th Annual Conference on Learning Theory (COLT), 2006. This work was supported in part by the IST Programme of the European Community, under the PASCAL Network of Excellence, IST-2002-506778, by a grant No. 1079/04 from the Israel Science Foundation, by a grant from BSF and an IBM faculty award. This publication only reflects the authors’ views.  相似文献   
88.
Antimicrobial peptides which adopt mainly or only beta-sheet structures have two or more disulfide bonds stabilizing their structure. The disruption of the disulfide bonds results in most cases in a large decrease in their antimicrobial activity. In the present study we examined the effect of d-amino acids incorporation on the structure and function of a cytolytic alpha-helical peptide which acts on erythrocytes and bacteria. The influence of a single or double d-amino acid replacement in alpha-helical peptides on their structure was reported previously in 50% 2,2,2, trifluoroethanol/water [Krause et al. (1995) Anal. Chem. 67, 252-258]. Here we used Attenuated Total Reflectance Fourier-Transform Infrared (ATR-FTIR) spectroscopy and found that the predominant structure of the wild-type peptide is alpha-helix in phospholipid membranes, whereas the structure of the diastereomer is beta-sheet. However, the linear, beta-sheet diastereomer preserved its cytolytic activity on bacteria but not on erythrocytes. Previous studies have shown that the ability of antimicrobial peptides to lyse bacteria but not normal mammalian cells correlated with their ability to disintegrate preferentially negatively charged, but not zwitterionic phospholipid membranes. In contrast, the diastereomer described here disrupts zwitterionic and negatively charged vesicles with similar potencies to those of the hemolytic wild-type peptide. Interestingly, whereas addition of a positive charge to the N-terminus of the wild-type peptide (which caused a minor effect on its structure) increased activity only towards some of the bacteria tested, similar modification in the diastereomer increased activity towards all of them. Furthermore, the modified wild-type peptide preserved its potency to destabilize zwitterionic and negatively charged vesicles, whereas the modified diastereomer had a reduced potency on zwitterionic vesicles but increased potency on negatively charged vesicles. Overall our results suggest that this new class of antimicrobial diastereomeric peptides bind to the membrane in 'carpet-like' manner followed by membrane disruption and breakdown, rather than forming a transmembrane pore which interfere with the bacteria potential. These studies also open a way to design new broad-spectrum antibacterial peptides.  相似文献   
89.
A series of peptides derived from three domains within the fusion protein of Sendai virus was synthesized and examined for their potential to inhibit the fusion of the virus with human red blood cells. These domains include the 'fusion peptide' and two heptad repeats, one adjacent to the fusion peptide (SV-163) and the other to the transmembrane domain (SV-473). Of all the peptides tested, only SV-473 was highly inhibitive. Using fluorescently-labelled peptides, the mechanism through which the SV-473 peptide inhibits the haemolytic activity of the virus was investigated. The results suggest that interactions of the active peptide with virion elements and lipid membranes are involved. Since it has recently been found that synthetic peptides corresponding to putative coiled-coil domains of the human immunodeficiency virus (HIV) type 1 transmembrane protein gp41 are potent inhibitors of HIV, we discuss the general property of virus-derived coiled-coil peptides as inhibitors of viral infection.  相似文献   
90.
Object-based attention was examined in 2 split-brain patients. A precued object could move within a visual field or cross the midline to the opposite field. Normal individuals show an inhibition in detecting signals in the cued object whether it moves within or between fields. Both patients showed this effect when the cued object moved within a visual field. When it crossed the midline into the opposite visual field, however, detection was faster in the cued box. These results reveal both facilitatory and inhibitory effects on attention that are object based and may last for several hundred milliseconds. However, the inhibition requires an intact corpus callosum for interhemispheric transfer, whereas the facilitation is transferred subcortically. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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