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31.
HB Wielandt 《Canadian Metallurgical Quarterly》1994,156(10):1438-1441
In October 1989 a representative sample consisting of 359 women (response rate = 77.9%) and 400 men (response rate = 76.3%) aged 16-20 years old was interviewed by the professional interviewer staff of the Institute for Social Research. The purpose of the investigation was to illustrate whether AIDS and "Safe sex"-campaigns have influenced young people. This paper consider the attitudes to contraception among teenagers. Generally, the reports are in accordance with an increasing popularity of the condom. Almost all answered that it was all right for a girl to bring a condom. The majority (313 (89.4%) among women and 311 (78.7%) among men) reported both partners to be responsible in relation to contraception. Still, it is commonly the female who brings up the question. Communication about contraception between the female and the male partner is of importance in order to impede sexually transmitted diseases and reduce the number of legally induced abortions among teenagers. The widespread attitude towards contraception as being a joint concern forms an appropriate basis to attain equality between the sexes in relation to communication about contraception. 相似文献
32.
J Degen E W?lke M Seiberling P Pintar G H?xter HB Steinhauer W Fischer 《Canadian Metallurgical Quarterly》1993,88(3):129-33, 171
The pharmacokinetics of the antidepressants amitriptyline oxide and trimipramine and their major metabolites amitriptyline, nor-triptyline and desmethyltrimipramine, were studied in twelve healthy male subjects (aged from 22 to 62 years) and twelve patients (aged from 25 to 73 years) with severe renal impairment (glomerular filtration rate < 10 ml/min). Oral single doses of 60 mg amitriptyline oxide and 50 mg trimipramine, separated by a washout period, were administered to all study participants. Blood and urine samples were collected up to 120 hours after administration. For trimipramine and desmethyltrimipramine, a new HPLC method was developed. The "Fischer Somatic and Undesired Effects Check List" was used for the assessment of adverse events. The mean plasma half-life and AUC of amitriptyline oxide and its metabolites were significantly higher in patients than in healthy adults. For trimipramine the AUC was significantly higher in patients. The plasma half-life of trimipramine was longer in patients, but statistically not significant. The maximum plasma concentrations for both drugs and metabolites were at an average distinctly higher in patients. Clearance rate of amitroptylinoxide and trimipramine also differed between the two groups. Correlating with these results a high incidence and a longer persistence (in most cases > 12 hours) and more pronounced adverse effects were noted in the patient group, whereas in volunteers adverse events were only observed up to approximately eight hours. 相似文献
33.
Fifteen fresh cadaver impacts were conducted in simulation of pedestrian-automobile accidents. The test sled configuration simulated an automobile bumper and hood in "standard" and "nosedive" situations as well as "hard" and "soft" impact surfaces. Instrumentation and film demonstrated large axial compression forces in the struck leg and considerable angular velocity of the torso in all modes. Dissection revealed primary injury at the impact site at low velocities with added remote injury at high velocities. Fracture of the lateral tibial plateau was most common. Lowering the bumper height offered the greatest protection against injury at moderate impact velocities. 相似文献
34.
Jeong-Ryeol Kim Geun-Kyu Choi Dong Kyun Yim Jong-Sung Park Kug Sun Hong 《Journal of Electroceramics》2006,17(1):65-69
Glasses in the ZnO-B2O3-MO3(M = W, Mo) ternary were examined as potential replacements to PbO-B2O3-SiO2-ZnO glass frits with the low firing temperature (500–600∘C) for the dielectric layer of a plasma display panels (PDPs). Glasses were melted in air at 950–1150∘C in a narrow region of the ternary using standard reagent grade materials. The glasses were evaluated for glass transition
temperature (T
g
), softening temperature (T
d
), the coefficient of thermal expansion (CTE), dielectric constant (ε
r
), and optical property. The glass transition temperature of the glasses varied between 470 and 560∘C. The coefficient of thermal expansion and the dielectric constant of the glasses were in the range of 5–8 × 10− 6/∘C and 8–10, respectively. The addition of MO3to ZnO-B2O3binary could induce the expansion of glass forming region, the reduction of T
g
and the increase in the CTE and the dielectric constant of the glasses. Also, the effect of the addition of MO3to ZnO-B2O3binary on the transmittance in the visible-light region (350–700 nm) was investigated. 相似文献
35.
Modular Reconfigurable Robots in Space Applications 总被引:6,自引:0,他引:6
Mark Yim Kimon Roufas David Duff Ying Zhang Craig Eldershaw Sam Homans 《Autonomous Robots》2003,14(2-3):225-237
Robots used for tasks in space have strict requirements. Modular reconfigurable robots have a variety of attributes that are well suited to these conditions, including: serving as many different tools at once (saving weight), packing into compressed forms (saving space) and having high levels of redundancy (increasing robustness). In addition, self-reconfigurable systems can self-repair and adapt to changing or unanticipated conditions. This paper will describe such a self-reconfigurable modular robot: PolyBot. PolyBot has significant potential in the space manipulation and surface mobility class of applications for space. 相似文献
36.
Haiping Du James Lam Kam Yim Sze 《Engineering Applications of Artificial Intelligence》2003,16(7-8):667-680
This paper presents an approach to design static output feedback and non-fragile static output feedback H∞ controllers for active vehicle suspensions by using linear matrix inequalities and genetic algorithms. A quarter-car model with active suspension system is considered in this paper. By suitably formulating the minimization problem of the sprung mass acceleration, suspension deflection and tyre deflection, a static output feedback H∞ controller and a non-fragile static output feedback H∞ controller are obtained. The controller gain is naturally constrained in the design process. The approach is validated by numerical simulation which shows that the designed static output feedback H∞ controller can achieve good active suspension performance in spite of its simplicity, and the non-fragile static output feedback H∞ controller has significantly improved the non-fragility characteristics over controller gain variations. 相似文献
37.
Sheng Yan Lok Yan Yim Rachel Chun Yee Tam Albert Chan Liwei Lu Chak Sing Lau Vera Sau-Fong Chan 《International journal of molecular sciences》2016,17(8)
Systemic lupus erythematosus (SLE) is a chronic multi-organ autoimmune disease characterized by hyperactivated immune responses to self-antigens and persistent systemic inflammation. Previously, we reported abnormalities in circulating and bone marrow (BM)-derived plasmacytoid dendritic cells (pDCs) from SLE patients. Here, we aim to seek for potential regulators that mediate functional aberrations of pDCs in SLE. BM-derived pDCs from NZB/W F1 mice before and after the disease onset were compared for toll-like receptor (TLR) induced responses and microRNA profile changes. While pDCs derived from symptomatic mice were phenotypically comparable to pre-symptomatic ones, functionally they exhibited hypersensitivity to TLR7 but not TLR9 stimulation, as represented by the elevated upregulation of CD40, CD86 and MHC class II molecules upon R837 stimulation. Upregulated induction of miR-155 in symptomatic pDCs following TLR7 stimulation was observed. Transfection of miR-155 mimics in pre-symptomatic pDCs induced an augmented expression of Cd40, which is consistent with the increased CD40 expression in symptomatic pDCs. Overall, our results provide evidence for miR-155-mediated regulation in pDC functional abnormalities in SLE. Findings from this study contribute to a better understanding of SLE pathogenesis and ignite future interests in evaluating the molecular regulation in autoimmunity. 相似文献
38.
Wang Byuck Suh Jae Yun Yim Dong Ho Bae 《Journal of Mechanical Science and Technology》2012,26(7):2143-2146
A pressboard consisting of an angle ring and a cap is installed at the primary and secondary coil windings of a transformer. This pressboard is related to transformer durability. Since transformer capacities are increasing, it is necessary to develop a pressboard of high voltage grade (above 150 kV). In this study, a press-forming technology was developed for the pressboard of a 154 kV transformer. To determine the optimum shape of the pressboard, the press-forming factors were experimentally evaluated through the mechanical tensile strength and AC withstand voltage tests under wet conditions. From the results, the optimum size and shape of the pressboard was found to be R15??R20 mm under a forming pressure of 10 MPa. When the relative humidity (RH) was less than 50%, the moisture absorption rate in oil decreased by 25??40% compared to that in air. However, when RH exceeded 50%, the difference in the moisture absorption rate between the cases of oil and air was just 8??10%. The AC withstand voltage of the pressboard was weak against moisture. The average AC withstand voltage at 40°C and RH of less than 50% decreased by about 15% compared to the dried condition, and the maximum value decreased by 30% at 40°C and RH of more than 50%. 相似文献
39.
Nam Seung-Hee Kim Young-Min Walsh Marie K. Yim Sun-Hee Eun Jong-Bang 《Food science and biotechnology》2016,25(1):31-39
This study was performed to characterize pear protease proteolytic activity and investigate the use of pear protease as a meat tenderizer. Pear protease was purified and stabilized by 5% dextrin during lyophilization (dry) or concentration (liquid). Pear protease was further characterized with respect to pH, thermodynamics, and enzyme kinetics. Pear protease was stable at a pH range of 5-8 with an optimum pH of 6.5. From Arrhenius plots, liquid protease showed higher temperature dependency (23.49 kJ/mol) than dry protease (18.62 kJ/mol) due to its higher activation energy. The kcat/Km, catalytic efficiency of enzyme, was similar with 2.9 and 2.7 µM/min with dry and liquid proteases. Pear protease was evaluated for its proteolytic activities with casein and beef myofibrillar proteins by individually and combination with fig and kiwifruit proteases. These result indicated that pear and kiwifruit proteases could be complementary to be a desirable product for meat tenderization. 相似文献
40.
Yim Sang Ryun Park Ga Young Lee Kwang Won Chung Myung-Sub Shim Soon-Mi 《Food science and biotechnology》2017,26(1):293-298
Food Science and Biotechnology - The objectives of this study was to examine the amount of total arsenic and arsenic speciation in different types of rice from two areas in Korea using inductively... 相似文献