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81.
This article looks at Mexican photographer Graciela Iturbide’s Cholos/as series taken on both sides of the border: in Los Angeles in 1986 and in Tijuana in 1989. The cholos/as, or gang members, have a complex relationship to Mexico; this response grows in part from the constructed nature of the border in general – a symbolic and relatively recent division between nations that does not represent lived reality or divisions between identities and cultures. As an outsider, Iturbide inserts visual cues throughout the series that tie the cholos/as’ lifestyle to its Mexican roots and historical legacies, thus recuperating the mexicanidad, or Mexican identity, that exists in the borderlands. The narrative thrust of this series is strong, foregrounding female agency and matrilineal family structures over traditional, heteropatriarchal conceptions of family; complex negotiations of personal identity; and generally emphasising the social ties of border communities and subcultural groups through a distinct aesthetic style that intervenes in traditional photographic genres like studio portraiture. Iturbide’s images form an origin story for the topicality of the US–Mexico border at the present moment and demonstrate that the issues of the border have been a critical point of inquiry for artists since the 1980s.  相似文献   
82.
Wireless Personal Communications - In this work, we propose a new and efficient algorithm to mitigate the signal look direction error problem in adaptive beamforming without broadening the main...  相似文献   
83.
1. Mechanical forces associated with blood flow play important roles in the acute control of vascular tone, the regulation of arterial structure and remodelling and the localization of atherosclerotic plaque. Uraemia is a proatherogenic process and is expected to be associated with impaired vascular reactivity.2. To study this, 12 male Wistar rats were rendered uraemic by five-sixths nephrectomy and 12 control rats were sham operated simultaneously. After 8 weeks a tail-cuff systolic blood pressure was recorded, blood samples were taken and the animals killed. Isolated femoral arteries were dissected and mounted on a pressure myograph and myogenic tone was assessed over a range of intravascular pressures from 40 to 160 mmHg. Histologically the arteries were comparatively examined for gross morphology, calcification and deposition of collagen.3.Biochemically the serum urea and creatinine were greater in the uraemic compared with the control rats (urea: 23.5+/-6 mmol/l and 6.8+/-01 mmol/l respectively, P not significant; creatinine: 130.7+/-13 mmol/l and 70.3+/-5 mmol/l respectively, P<0.01) but systolic blood pressure was the same in both groups (control, 97+/-1 mmHg; uraemic, 98+/-2 mmHg), compatible with mild uraemia.4. Myogenic tone was significantly greater in uraemic vessels (7.3+/-1.8% versus 2.3+/-0. 4% in control, P=0.01). The actual vessel lumen diameter was also smaller in pressurized uraemic vessels compared with control vessels (471+/-30 microm versus 604+/-33 microm, P<0.01) after equilibration in physiological salt solution. However, when incubated in calcium-free physiological salt solution, the passive internal diameter was similar in uraemic vessels (538+/-25 microm compared with 595+/-31 microm in control). Histologically, there were no differences between the two groups.5. We conclude that some aspects of vascular reactivity are altered in mild experimental uraemia as shown by a reduced internal lumen diameter and increased myogenic tone. Furthermore, these changes are apparent in the absence of hypertension and precede structural changes.  相似文献   
84.
A constitutive model based on the theory of plasticity is proposed to characterize the stress-strain behaviour of plain concrete under three-dimensional loading. The model incorporates the third stress invariant in the formulation that allows variation of shear strength with the orientation of stress paths on the octahedral plane. Also, it allows variation of the shape of the yield surface on the octahedral plane with confining pressure. An algorithm is developed and used to evaluate the associated material constants in the optimum manner. Stress-strain responses are back-predicted for a number of stress paths using the proposed model and the results are compared with experimental observations. Overall, good agreement between the experimental data and predicted response is obtained.  相似文献   
85.
OBJECTIVE: To determine the prevalence of obesity and reference percentile curves of body mass index (BMI; kg/m2) in Japanese adults. DESIGN: Cross-sectional nationwide surveys (The National Nutrition Survey, Japan) carried out in 1990-1994. A sample of 23,556 males and 28,751 females aged 15-84 y was used for this analysis. RESULTS: The prevalence of grades 1 (BMI: 25.0-29.9), 2 (30.0-39.9) and 3 (> or = 40.0) overweight, was estimated to be 24.3%, 1.84% and 0.019% in males, respectively, and 20.2%, 2.87% and 0.032% in females, respectively, subjects aged 35-64 y after standardization to the age-distribution of the standard world population (WHO, 1993). The age-standardized prevalence of obesity (for BMI > or = 26.4, a criterion of the Japan Society for the Study of Obesity; and > or = 30.0 was 13.6% and 1.86% in males, respectively, and 13.5% and 2.90% in females, respectively, subjects aged 35-64 y. CONCLUSIONS: The standardized prevalence of obesity (BMI > or = 30.0) in Japanese adults was quite low compared with the data in western populations.  相似文献   
86.
Crude extract of Rubia cordifolia (RC) was tested in isolated tissue preparations for its possible calcium channel antagonistic activity. RC suppressed the spontaneous contractions of guinea-pig atria, rabbit jejunum and rat uterus in a concentration dependent manner (0.1-3 mg/ml). In rabbit aorta, it inhibited norepinephrine (10 microM) and KCl (80 mM) induced contractions. Replacement of physiological salt solution with calcium free solution abolished the spontaneous movements of rabbit jejunum. However, addition of calcium (25 micrograms/ml) in the tissue bath restored the spontaneous movements. When the tissues were pretreated with plant extract (1 mg/ml) or verapamil (0.5 microgram/ml), addition of calcium failed to restore spontaneous contractions. These results indicate that the plant extract exhibits spasmolytic activity similar to that of verapamil suggestive of presence of calcium channel blocker like constituent(s) in this plant.  相似文献   
87.
The effects of taurine in parenteral nutrition (PN)-related hepatic dysfunction are controversial. The aims of the present study were to evaluate the effects of taurine on hepatic function and on lidocaine metabolism, using two strengths of taurine (15 and 50 mg/dl) that are present in commercially available preparations. Animals (N > or = 4) were randomly assigned to one of the four 7-day treatment groups: chow-fed (CF); dextrose/amino acids (PN); dextrose/amino acids and taurine, 15 mg/dl (T15); dextrose/amino acids and taurine, 50 mg/dl (T50). Between 40-75% of the animals treated with PN developed steatosis. The origin of steatosis was zonal specific and dependent on taurine treatment. All livers in the CF group had a normal cellular architecture. Lidocaine metabolism was found to be impaired in groups PN, T15, and T50. This was indicated by a significant reduction in the intrinsic clearance values: 70%, 76%, and 85% in groups PN, T15, and T50, respectively (p < 0.05). Metabolites-to-drug ratios indicated that N-dealkylation, m-hydroxylation, and aryl methyl hydroxylation were significantly reduced in all treatment groups; the most pronounced effect was observed in the T50 group. These findings suggest that PN infusion results in impaired liver function, and the reduction of drug elimination rate is exacerbated by the addition of taurine.  相似文献   
88.
The present study deals with the deposition of silver particles onto knitted fabrics for possible applications in electrotherapy. The performance of silver‐coated fabrics was evaluated based on number of properties such as electrical conductivity, physiological comfort, antibacterial, and durability. Furthermore, the conductive fabrics were subjected to various repeated extensions and change in electrical resistivity was examined to simulate the performance of electrodes under various movements of human body. With increase in extension till 80%, very small change in volume electrical resistance was observed and after 90% extension, the electrical resistance was found to increase significantly. The volume resistance was found to remain constant for repeated extensions of over 100 cycles and also there was insignificant change in electrical resistivity when constant current was applied over prolonged time. The utility of silver‐coated fabrics can be expected as flexible textile electrodes in transcutaneous electrical nerve stimulation electrotherapy applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46357.  相似文献   
89.
OBJECTIVE: To determine the influence of sperm morphology and the number of motile sperm inseminated on the outcome of IUI in hMG-stimulated cycles and to establish lower limits for these variables below which the expectation of pregnancy is limited. DESIGN: Retrospective study of data from 1990 to 1992. SETTING: Tertiary referral Reproductive Medicine Unit. Patients: Couples with bilaterally patent fallopian tubes, and > or = 200,000 motile sperm recovered in a trial preparation before treatment. No other semen criteria were used to exclude couples. Women were stimulated with hMG irrespective of whether they were ovulatory or anovulatory. The study comprised 163 couples who underwent 330 cycles. MAIN OUTCOME MEASURES: Pregnancy rate (PR) per cycle was related to the percentage normal sperm morphology in the fresh semen sample and the number of motile sperm inseminated after sperm preparation by swim-up or Percoll gradients. RESULTS: The overall PR was 16.1% per cycle. The PR was highest in the first cycle of treatment (21.4%) and declined in the second and third cycles. The miscarriage rate was 10.4% and the incidence of multiple pregnancies was 13.9%. Two groups of patients were defined on the basis of sperm morphology: a "poor outcome" group ( < or = 10% normal) and a "good outcome" group ( > 10% normal). The PRs in these two groups were 4.3% and 18.2%, respectively, and the cumulative PRs after three cycles were 8.3% and 40.1%, respectively. The number of motile sperm inseminated did not significantly affect the PR. CONCLUSIONS: The degree of teratozoospermia affected the PR in hMG-stimulated IUI cycles and a normal morphology value of 10% in the fresh semen distinguished couples with good and poor outcomes. In contrast, the number of motile sperm inseminated did not significantly influence IUI outcome.  相似文献   
90.
Wireless Personal Communications - Internet of Multimedia Things (IoMT), a special subset of Internet of Things (IoT), is a novel paradigm which is progressively increasing and gaining in...  相似文献   
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