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21.
NEED—The effect of dimensional variability of sheet thickness (tolerance) and tool misalignment is poorly understood for the clinching process. Finite element analysis (FEA) is valuable but requires a lot of and is difficult to verify in this situation due to the asymmetrical geometry and nonlinear plasticity. OBJECTIVE—The objective of this work was to determine the effect of thickness tolerance, tool misalignment and sheet placement (top vs. bottom) in the clinching process, by use of analogue modelling with plasticine. METHOD—Experiments used a scaled-up punch and die, with plasticine as the analogue. Thickness tolerances were represented by sheet thicknesses of 11 and 7 mm, 12 and 8 mm, 8 and 12 mm and 13 and 9 mm for upper and lower sheets, respectively. Two types of lubricant were tested between sheets: glycerine and silicone oil. Angular variability was also introduced. Measured parameters were interlock (also called undercut) and neck thickness. Analogue results for deformation were compared with microscopy of metal clinching. FINDINGS—The results reveal that the multiscale analogue model is an efficient tool for studying the effect of dimensional deviation on a clinch joint. Thickness tolerance showed a critical relationship with interlock, namely a reduction to about half that of the nominal, for both maximum and least material conditions. Increased angular misalignment also reduced the interlock. Compared with glycerine, silicone oil tests showed reduced interlock, possibly the result of a lower coefficient of friction. ORIGINALITY—This work demonstrates the usefulness of analogue modelling for exploring process variability in clinching. The results also show that significant effects for sheet placement are ductility, lubricant (friction), thickness of samples and tool misalignment. 相似文献
22.
Kubaszek A Pihlajamäki J Komarovski V Lindi V Lindström J Eriksson J Valle TT Hämäläinen H Ilanne-Parikka P Keinänen-Kiukaanniemi S Tuomilehto J Uusitupa M Laakso M;Finnish Diabetes Prevention Study 《Diabetes》2003,52(7):1872-1876
High levels of cytokines are risk factors for type 2 diabetes. Therefore, we investigated whether the promoter polymorphisms of the tumor necrosis factor-alpha (TNF-alpha; G-308A) and interleukin 6 (IL-6; C-174G) genes predict the conversion from impaired glucose tolerance (IGT) to type 2 diabetes in the Finnish Diabetes Prevention Study. Altogether, 490 overweight subjects with IGT whose DNA was available were randomly divided into one of the two treatment assignments: the control group and the intensive, individualized diet and exercise intervention group. The -308A allele of the TNF-alpha gene was associated with an approximate twofold higher risk for type 2 diabetes compared with the G-308G genotype (odds ratio 1.80, 95% CI 1.05-3.09; P = 0.034). Subjects with both the A allele of the TNF-alpha gene and the C-174C genotype of the IL-6 gene had a 2.2-fold (CI 1.02-4.85, P = 0.045) higher risk of developing type 2 diabetes than subjects without the risk genotypes. We conclude that the -308A allele of the promoter polymorphism (G-308A) of the TNF-alpha gene is a predictor for the conversion from IGT to type 2 diabetes. Furthermore, this polymorphism seems to have a gene-gene interaction with the C-174C genotype of the IL-6 gene. 相似文献
23.
Jaana I. Halonen Jussi Vahtera Stephen Stansfeld Tarja Yli-Tuomi Paula Salo Jaana Pentti Mika Kivim?ki Timo Lanki 《Environmental health perspectives》2012,120(10):1391-1396
Background: Associations between traffic noise and sleep problems have been detected in experimental studies, but population-level evidence is scarce.Objectives: We studied the relationship between the levels of nighttime traffic noise and sleep disturbances and identified vulnerable population groups.Methods: Noise levels of nighttime–outdoor traffic were modeled based on the traffic intensities in the cities of Helsinki and Vantaa, Finland. In these cities, 7,019 public sector employees (81% women) responded to postal surveys on sleep and health. We linked modeled outdoor noise levels to the residences of the employees who responded to the postal survey. We used logistic regression models to estimate associations of noise levels with subjectively assessed duration of sleep and symptoms of insomnia (i.e., difficulties falling asleep, waking up frequently during the night, waking up too early in the morning, nonrestorative sleep). We also used stratified models to investigate the possibility of vulnerable subgroups.Results: For the total study population, exposure to levels of nighttime–outside (Lnight, outside) traffic noise > 55 dB was associated with any insomnia symptom ≥ 2 nights per week [odds ratio (OR) = 1.32; 95% confidence interval (CI): 1.05, 1.65]. Among participants with higher trait anxiety scores, which we hypothesized were a proxy for noise sensitivity, the ORs for any insomnia symptom at exposures to Lnight, outside traffic noises 50.1–55 dB and > 55 dB versus ≤ 45 dB were 1.34 (95% CI: 1.00, 1.80) and 1.61 (95% CI: 1.07, 2.42), respectively.Conclusions: Nighttime traffic noise levels > 50 dB Lnight, outside was associated with insomnia symptoms among persons with higher scores for trait anxiety. For the total study population, Lnight, outside > 55 dB was positively associated with any symptoms. 相似文献
24.
Vantte Kilappa Kailiang Xu Petro Moilanen Erkki Heikkola Dean Ta Jussi Timonen 《Ultrasound in medicine & biology》2013
The fundamental flexural guided wave (FFGW), as modeled, for example, by the A0 Lamb mode, is a clinically useful indicator of cortical bone thickness. In the work described in this article, we tested so-called multiridge-based analysis, based on the crazy climber algorithm and short-time Fourier transform, for assessment of the FFGW component recorded by a clinical array transducer featuring a limited number of elements. Methods included numerical finite-element simulations and experiments in bone phantoms and human radius specimens (n = 41). The proposed approach enabled extraction of the FFGW component and determination of its group velocity. This group velocity was in good agreement with theoretical predictions and possessed reasonable sensitivity to cortical width (r2 = 0.51, p < 0.001) in the in vitro experiments. It is expected that the proposed approach enables related clinical application. Further work is still needed to analyze in more detail the challenges related to the impact of the overlying soft tissue. 相似文献
25.
Aloysius Sheng-Ting Leow Ching-Hui Sia Benjamin Yong-Qiang Tan Joshua Ping-Yun Loh 《Journal of thrombosis and thrombolysis》2018,46(1):68-73
Left ventricular (LV) thrombus is commonly seen in patients with extensive anterior ST-elevation myocardial infarction. The standard of care for LV thrombus is anticoagulation with warfarin. However, there has been an increasing trend of case reports using non-vitamin K antagonist oral anticoagulants (NOAC) for the treatment of LV thrombus. This study aimed to perform a meta-summary of the literature to characterise and evaluate the safety and feasibility of using NOAC in patients with LV thrombus. We searched for articles published in four electronic databases: PubMed, EMBASE, Scopus and Google Scholar using an appropriate keyword/MeSH term search strategy. Twenty-four studies comprising 36 patients were included in the analysis. Rivaroxaban was used in majority of patients (47.2%), whilst Apixaban and Dabigatran were prescribed in 25.0% and 27.8% of patients respectively. The most commonly associated risk factor found was post-acute myocardial infarction in 15 patients (41.7%). LV thrombus resolution was met by most patients (87.9%), and the median duration of treatment to resolution was 30.0 days (IQR?=?22.5–47.0). One non-fatal bleeding event (3.0%) and no embolic events were reported. The use of NOAC may have a role in the treatment of LV thrombus in selected patients. Further randomized controlled trials are needed to evaluate this treatment strategy. 相似文献
26.
Glenn L Sia Su Clara Mae R Mariano Nikki Shayne A Matti Gliceria B Ramos 《亚太热带病杂志(英文版)》2012,2(1):51-54
ObjectiveTo assess the parasitic infestation of vegetables in selected markets in Metro Manila, Philippines.MethodsA total of 80 vegetables were purchased from public and private markets in Munoz, Quezon City, and Alabang, Muntinlupa City. Vegetables were washed, and the washings were collected and examined for parasitic organisms.ResultsIn all vegetables examined, 36 of 80 (45.0%) were infested with parasitic organisms. Vegetables obtained from Muntinlupa City showed that 17 of 40 (42.5%) have parasitic infestation as compared with those obtained from Quezon City with 19 of 40 (47.5%). Significant differences on the parasitic organisms existed between the public and private markets and between the two locations (P<0.05).ConclusionsFindings indicate that vegetables can be potential source of parasitic infection. There is a need to be vigilant in ensuring that foodstuffs sold in our market systems are safe and fit for consumption. 相似文献
27.
Jussi K. Huttunen 《Nutrition and cancer》2013,65(1):19-22
Many furan‐containing natural products that induce increased activity of the glutathione S‐transferase (GST) enzyme system have been found to inhibit tumorigenesis in laboratory animals. 2‐n‐Heptylfuran (HF) and 2‐n‐butylthiophene (BT), a sulfur analogue of furan, are two of the many furans and thiophenes formed during the roasting process of meat. BT and HF, when administered by gavage at doses that ranged from 11 to 90 μmol, induced increased GST activity in various tissues of A/J mice. At 90 μmol/dose, BT induced increased GST in the liver, small bowel mucosa, and lung. No increase in enzyme activity was found in the forestomach. HF was an enzyme inducer in the liver, small bowel mucosa, and forestomach but was inactive in the lung. The acid‐soluble sulfhydryl level, a good measure of glutathione contents in tissues, was examined in tissue homogenates from mice treated with BT and HF. BT induced significant increase of GSH in the liver and lung at the higher doses. No change was observed in either the small bowel mucosa or the forestomach. A 50‐μmol dose of HF was found to increase GSH level in all four tissues studied. The inhibition of lung and forestomach tumorigenesis was carried out with A/J mice using benzo[a]pyrene as the carcinogen. BT treatment resulted in a reduction of tumor multiplicity in the lung and forestomach. The tumor incidence in the forestomach was reduced significantly. The potency of HF as inhibitor of carcinogenesis was similar to that of BT in the forestomach of mice. In the lung, HF was found to be ineffective as an inhibitor of pulmonary adenoma formation. These results suggest that furan‐ and thiophene‐containing compounds may be effective inhibitors of chemical carcinogenesis. 相似文献
28.
Laura Pirkola Reijo Laatikainen Jussi Loponen Sanna-Maria Hongisto Markku Hillil? Anu Nuora Baoru Yang Kaisa M Linderborg Riitta Freese 《World journal of gastroenterology : WJG》2018,(11)
AIM To compare the effects of regular vs low-FODMAP rye bread on irritable bowel syndrome(IBS) symptoms and to study gastrointestinal conditions with Smart Pill?.METHODS Our aim was to evaluate if rye bread low in FODMAPs would cause reduced hydrogen excretion,lower intraluminal pressure,higher colonic p H,different transit times,and fewer IBS symptoms than regular rye bread.The study was a randomized,double-blind,controlled cross-over meal study.Female IBS patients(n = 7) ate study breads at three consecutive meals during one day.The diet was similar for both study periods except for the FODMAP content of the bread consumed during the study day.Intraluminal p H,transit time,and pressure were measured by Smart Pill,an indigestible motility capsule.RESULTS Hydrogen excretion(a marker of colonic fermentation) expressed as area under the curve(AUC)(0-630 min) was [median(range)] 6300(1785-10800) ppm?min for low-FODMAP rye bread and 10 635(4215-13080) ppm?min for regular bread(P = 0.028).Mean scores of gastrointestinal symptoms showed no statistically significant differences but suggested less flatulence after low-FODMAP bread consumption(P = 0.063).Intraluminal pressure correlated significantly with total symptom score after regular rye bread(ρ = 0.786,P = 0.036) and nearly significantly after lowFODMAP bread consumption(ρ = 0.75,P = 0.052).We found no differences in p H,pressure,or transit times between the breads.Gastric residence of Smart Pill was slower than expected.Smart Pill left the stomach in less than 5 h only during one measurement(out of 14 measurements in total) and therefore did not follow on par with the rye bread bolus.CONCLUSION Low-FODMAP rye bread reduced colonic fermentation vs regular rye bread.No difference was found in median values of intraluminal conditions of the gastrointestinal tract. 相似文献
29.
Multiple chromosomal regions and polymorphisms of several candidate genes have been linked to or associated with atopic diseases (hayfever, asthma, allergic eczema and rhinitis). In this mini-review, we present data demonstrating that the genetic regulation of the inflammatory response makes a major contribution to the risk of atopy. These data also suggest that the quantity (or quality) of the inflammation affects the priming phase of atopy, i.e., that induced by allergens or infectious agents in early childhood. 相似文献
30.
S. Wayne Miles Janie Sheridan Bruce Russell Rob Kydd Amanda Wheeler Carina Walters Greg Gamble Peta Hardley Maree Jensen Kimmo Kuoppasalmi Pekka Tuomola Jaana Föhr Outi Kuikanmäki Helena Vorma Raimo Salokangas Antti Mikkonen Mika Kallio Jussi Kauhanen Vesa Kiviniemi Jari Tiihonen 《Addiction (Abingdon, England)》2013,108(7):1279-1286