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31.
Franko Debra L.; Striegel-Moore Ruth H.; Bean Judy; Tamer Robert; Kraemer Helena C.; Dohm Faith-Anne; Crawford Patricia B.; Schreiber George; Daniels Stephen R. 《Canadian Metallurgical Quarterly》2005,24(6):586
Depression in adolescent girls may result in negative consequences in young adulthood. The Center for Epidemiologic Studies Depression Scale (CES-D) was administered to 1,727 Black and White girls ages 16 to 18 years who participated in the National Heart, Lung, and Blood Institute's Growth and Health Study. Three years later, women in the depressed groups were more likely to be current smokers, had attained a lower level of education, and reported lower self-worth relative to the nondepressed group. Body dissatisfaction, eating concerns, and loneliness were greater in the depressed groups. Relative to Black women, White women who were moderately depressed during adolescence reported more health care services utilization in young adulthood. Prevention efforts for depressed adolescents should be broadly focused to improve young adult outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A MEMS in-line separable connector containing features for precision self-alignment is demonstrated. The concept relies on sliding connection between female and male halves to induce vertical deflections of a set of flexible conductors and establish stable electrical contacts. Electrodeposited photoresist is used to fabricate thick, nonplanar conductors, shaped by a silicon substrate that has previously been terraced by anisotropic etching. Further etched features ensure transverse and vertical self-alignment between conductor elements during mating. Prototype 10-way connectors are demonstrated with 200 /spl mu/m wide conductors on a 250-/spl mu/m pitch. Mechanical reliability of contacts during repeated mating and demating is demonstrated, and initial measurement of contact resistance reveals an encouraging value of 30 m/spl Omega/. 相似文献
33.
Kaisa Grönman Risto Soukka Terhen Järvi‐Kääriäinen Juha‐Matti Katajajuuri Mika Kuisma Heta‐Kaisa Koivupuro Margareetta Ollila Marja Pitkänen Olli Miettinen Frans Silvenius Rabbe Thun Helena Wessman Lassi Linnanen 《Packaging Technology and Science》2013,26(4):187-200
The environmental impacts of packages have been found to be relatively small compared with the food items they contain. Furthermore, from the environmental and operational point of view, the most significant task of the package is to protect the product, which is important to acknowledge in the packaging design process. This study introduces a guiding framework for designing sustainable food packaging. In this approach, the entire life cycle of the product–package combination is taken into consideration. The emphasis is on the prevention of food losses in packaging design as a major environmental criterion. Consideration of the properties of both the package and the product itself when designing the final package will lead to a better end result with smaller product losses and environmental impacts. By using different assessment methods in the different stages of the packaging design, the sustainability of the package can be enhanced. The decision making of the packaging designer is facilitated with methods that are introduced step by step and in a certain order that will also allow for corrective measures through back‐loops in the design process. The purpose is to integrate sustainability aspects at all stages firmly into the design process. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
34.
Natacha Kalline de Oliveira Lucyene Miguita Tais Helena Costa Salles Marcos Akira d’Ávila Márcia Martins Marques Maria Cristina Zindel Deboni 《Journal of Materials Science》2018,53(23):15757-15768
The aim of this study was to analyze the influence of nanoporous structure of polymeric biomaterials on the in vitro osteogenic induction of human stem cells. An electronic search in three databases (MEDLINE, SCOPUS, and Web of Science) was performed for articles that were published before May 2018. In vitro studies were included if they met the following criteria: (1) the use of polymeric scaffolds (natural or synthetic); (2) the co-culture of human stem cells with the scaffold; and (3) cell viability, proliferation, and osteogenic differentiation assays. The main characteristics of the published studies were summarized, and a quality assessment tool was used to analyze methodological features. Eighty-eight potential articles were firstly retrieved. Thirteen were eligible for qualitative analysis. Only three studies characterized cell stemness. Nanostructure of the scaffolds showed a significant influence on viability, proliferation, and osteogenic differentiation of human stem cells. Combination of porosity between 72 and 93% and a large range diameter between 50 and 224 μm resulted in more remarkable cellular proliferation and differentiation. Porous polymeric scaffolds can be functionalized by stem cells leading to osteogenic induction. High standards of laboratory practice and accurate methodological reporting are essential for the credibility of the results. 相似文献
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Two interesting space-time coding schemes for communication systems are the recently proposed differential space-time modulation (DSTM) scheme and the differential space-code modulation (DSCM) scheme. DSCM gives better performance than DSTM by exploiting the spatial degree-of-freedom to suppress interference. We show that, for DSCM, a maximum-likelihood (ML) demodulation approach, based on a deterministic channel model, improves the performance significantly compared to a previously proposed stochastic channel model based method 相似文献
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Ridge waveguide pseudomorphic InGaAs/GaAs/AlGaAs single-quantum-well lasers exhibiting record high quantum efficiencies and high output power densities (105 mW per facet from a 6 μm wide stripe) at a lasing wavelength of 980 nm are discussed that were fabricated from a graded index separate confinement heterostructure grown by molecular beam epitaxy. Life testing at an output power of 30 mW per uncoated facet reveals a slow gradual degradation during the initial 500 h of operation after which the operating characteristics of the lasers become stable. The emission wavelength, the high output power, and the fundamental lateral mode operation render these lasers suitable for pumping Er3+-doped fiber amplifiers 相似文献
40.
Hannes M. Findeisen Vivienne C. Voges Laura C. Braun Jannik Sonnenberg Dennis Schwarz Helena Krner Holger Reinecke Yahya Sohrabi 《International journal of molecular sciences》2022,23(11)
Reprogramming of metabolic pathways in monocytes and macrophages can induce a proatherosclerotic inflammatory memory called trained innate immunity. Here, we have analyzed the role of the Liver X receptor (LXR), a crucial regulator of metabolism and inflammation, in oxidized low-density lipoprotein (oxLDL)-induced trained innate immunity. Human monocytes were incubated with LXR agonists, antagonists, and oxLDL for 24 h. After five days of resting time, cells were restimulated with the TLR-2 agonist Pam3cys. OxLDL priming induced the expression of LXRα but not LXRβ. Pharmacologic LXR activation was enhanced, while LXR inhibition prevented the oxLDL-induced inflammatory response. Furthermore, LXR inhibition blocked the metabolic changes necessary for epigenetic reprogramming associated with trained immunity. In fact, enrichment of activating histone marks at the IL-6 and TNFα promotor was reduced following LXR inhibition. Based on the differential expression of the LXR isoforms, we inhibited LXRα and LXRβ genes using siRNA in THP1 cells. As expected, siRNA-mediated knock-down of LXRα blocked the oxLDL-induced inflammatory response, while knock-down of LXRβ had no effect. We demonstrate a specific and novel role of the LXRα isoform in the regulation of oxLDL-induced trained immunity. Our data reveal important aspects of LXR signaling in innate immunity with relevance to atherosclerosis formation. 相似文献