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排序方式: 共有994条查询结果,搜索用时 15 毫秒
21.
D. M. Allen H. J. Almond K. Bedner M. Cabeza B. Courtot A. Duval S. A. Impey M. Saumer 《Microsystem Technologies》2009,15(8):1287-1291
The objective of this research was to study the influence of electroplating parameters on electrodeposit characteristics for
the production of nickel (Ni) and nickel–iron (Ni–Fe) microparts by photoelectroforming. The research focused on the most
relevant parameter for industry, which is the current density, because it determines the process time and the consumed energy.
The results of the Ni and Ni–Fe characterisations can be divided into two aspects closely linked with each other: the morphology
and the hardness. 相似文献
22.
Rasmussen CD Jørgensen MB Carneiro IG Flyvholm MA Olesen K Søgaard K Holtermann A 《Ergonomics》2012,55(2):256-264
Worksite health promotion is seldom offered to workers who are low-educated and multi-ethnic, possibly due to an assumption that they are more reluctant to participate. Furthermore, little has been done to promote health at female-dominated workplaces. The main aim of this study was to investigate differences in participation among immigrant and Danish cleaners throughout a 1-year randomised controlled study tailored to cleaners and carried out in predominantly female workplaces. No significant differences in ethnicity were found in consent and participation throughout the 1-year intervention. Dropout was equally distributed among Danish and immigrant cleaners. This study indicates that a worksite health promotion intervention among a female-dominated, high-risk occupation such as cleaning can be equally appealing for Danes and immigrants. PRACTITIONER SUMMARY: This study provides insight about participation of Danish and immigrant cleaners in a worksite health promotion intervention in a predominantly female occupation. For attaining high participation and low dropout in future worksite health promotion interventions among cleaners, the intervention ought to not only target the ethnic background of the workers, but also to be specifically tailored to the job group. 相似文献
23.
Phillips Tamara J.; Broadbent Julie; Burkhart-Kasch Sue; Henderson Carly; Wenger Charlotte D.; McMullin Carrie; McKinnon Carrie S.; Cunningham Christopher L. 《Canadian Metallurgical Quarterly》2005,119(4):892
Short-term selective breeding created mouse lines divergent for ethanol drinking (high drinking short-term selected line [STDRHI], low drinking [STDRLO]) or ethanol-induced conditioned taste aversion (CTA; high [HTA], low [LTA]). Compared with STDRLO, STDRHI mice consumed more saccharin and less quinine, exhibited greater ethanol-induced conditioned place preference (CPP), and showed reduced ethanol stimulation and sensitization under some conditions; a line difference in ethanol-induced CTA was not consistently found. Compared with LTA, HTA mice consumed less ethanol but were similar in saccharin consumption, sensitivity to ethanol-induced CPP, and ethanol-induced locomotor stimulation and sensitization. These data suggest that ethanol drinking is genetically associated with several reward-and aversion-related traits. The interpretation of ethanol-induced CTA as more genetically distinct must be tempered by the inability to test the CTA lines beyond Selection Generation 2. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Bingo Wing‐Kuen Ling Charlotte Yuk‐Fan Ho Raymond Shing‐Keung Leung Peter Kwong‐Shun Tam 《International Journal of Circuit Theory and Applications》2004,32(2):57-64
This letter explains the oscillatory behaviours exhibited in a second‐order digital filter with saturation‐type non‐linearity via the Hopf bifurcation theorem. It is shown that depending on the bifurcation parameter, the state variables may converge to zero even when the eigenvalues of the system matrix are outside the unit circle. Copyright © 2004 John Wiley & Sons, Ltd. abstract 相似文献
25.
26.
Clémence Demangel Delphine Auzène Muriel Vayssade Jean-Luc Duval Pascale Vigneron Marie-Danièle Nagel Jean-Claude Puippe 《Materials science & engineering. C, Materials for biological applications》2012,32(7):1919-1925
Metal injection molding (MIM) is a near net shape manufacturing method that allows for the production of components of small to moderate size and complex shape. MIM is a cost-effective and flexible manufacturing technique that provides a large innovative potential over existing methods for the industry of implantable devices. Commercially pure titanium (CP-Ti) samples were machined to the same shape as a composite feedstock with titanium and polyoxymethylene, and these metals were injected, debinded and sintered to assess comparative biological properties. Moreover, we treated MIM-Ti parts with BIOCOAT®, BIODIZE® and BIOCER®, three different anodic oxidation techniques that treat titanium using acid, alkaline and anion enriched electrolytes, respectively. Cytocompatibility as well as morphological and chemical features of surfaces was comparatively assessed on each sample, and the results revealed that MIM-Ti compared to CP-Ti demonstrated a specific surface topography with a higher roughness. MIM-Ti and BIOCER® samples significantly enhanced cell proliferation, cell adhesion and cell differentiation compared to CP-Ti. Interestingly, in the anodization post-treatment established in this study, we demonstrated the ability to improve osseointegration through anionic modification treatment. The excellent biological response we observed with MIM parts using the injection molding process represents a promising manufacturing method for the future implantable devices in direct contact with bones. 相似文献
27.
28.
Anna F. Horn Nina S. Nielsen Charlotte Jacobsen 《International Journal of Food Science & Technology》2012,47(5):1097-1108
The objective of this study was to investigate the protective effect of five different emulsifiers on iron‐mediated lipid oxidation in 70% fish oil‐in‐water emulsions. The emulsifiers were either based on protein (whey protein isolate and sodium caseinate) or based on phospholipid (soy lecithin and two milk phospholipids with different phospholipid contents, MPL20 and MPL75). Lipid oxidation was studied at pH 4.5 and 7.0, and results were compared to lipid oxidation in neat fish oil. Results showed that all emulsions oxidised more than neat oil. Furthermore, emulsions prepared with proteins oxidised more at low pH than at high pH, and casein emulsions oxidised the least (Peroxide value (PV) at day 7 was 0.5–0.7 meq kg?1). Among emulsions prepared with phospholipids, emulsions with MPL75 were the most oxidised followed by emulsions prepared with lecithin and MPL20. Thus, PV in MPL75 emulsions was 5.0–5.5 meq kg?1 at day 7 compared with 0.9–1.9 meq kg?1 in MPL20 emulsions. 相似文献
29.
ABSTRACT: BACKGROUND: Weight loss is often difficult to achieve in individuals with type 2 diabetes and anti-obesity drugs are often advocated to support dietary intervention. Despite the extensive use of centrally acting anti-obesity drugs, there is little evidence of how they affect dietary composition. We investigated changes in energy intake and dietary composition of macro- and micronutrients following therapy with the endocannabinoid receptor blocker, rimonabant. METHODS: 20 obese patients with type 2 diabetes were studied before and after 6 months dietary intervention with rimonabant. Dietary intervention was supervised by a diabetes dietician. Five-day food diaries were completed at baseline and at 6 months and dietary analysis was performed using computer software (Dietplan 6). RESULTS: After 6 months, (compared with baseline) there were reductions in weight (107+/-21Kg versus 112+/-21, p<0.001, 4% body weight reduction), and improvements in HbA1c (7.4+/-1.7 versus 8.0+/-1.6%, p<0.05) and HDL cholesterol. Intake of energy (1589+/-384 versus 2225+/-1109kcal, p<0.01), carbohydrate (199+/-74 versus 273+/-194g, p<0.05), protein (78+/-23 versus 98+/-36g, p<0.05), fats (55+/-18 versus 84+/-39g, p<0.01) and several micronutrients were reduced. However, relative macronutrient composition of the diet was unchanged. Improvement in blood glucose was strongly correlated with a reduction in carbohydrate intake (r = 0.76, p<0.001). CONCLUSIONS: In obese patients with type 2 diabetes, rimonabant in combination with dietary intervention led to reduced intake of energy and most macronutrients. Despite this, macronutrient composition of the diet was unaltered. These dietary changes (especially carbohydrate restriction) were associated with weight loss and favourable metabolic effects. 相似文献
30.
Hwa Jung Kim Jeongah Ko Charlotte Storni Hong Ji Song Young Gyu Cho 《Journal of Functional Foods》2012,4(1):287-293
Overweight and obesity have become a global epidemic and they may impair health. Traditional use and growing evidence indicate that mate (Ilex paraguariensis A. St.-Hil.) may be helpful in losing excessive weight and fat. The present randomized, double-blind, placebo-controlled study evaluated efficacy and safety of an extract from green mate in 60 overweight subjects aged 20–39 years during 6-weeks. Body composition was measured by Dual-Energy X-ray Absorptiometry (DEXA) at baseline and after 6 weeks. Body weight, body mass index (BMI), waist circumference (WC) and various safety parameters were monitored. After 6 weeks, subjects taking mate experienced a significantly greater reduction of percent of body fat (?0.3% vs. +0.6%, p = 0.04) and fat mass (?0.5 kg vs. +0.2 kg, p = 0.04) than placebo. No significant differences were observed in other measurements. No adverse events occurred and all safety parameters were within normal ranges during the study in both groups. Thus, taking green mate extract reduced body fat after 6 weeks, while the treatment was safe and well tolerated. 相似文献