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51.
52.
In this paper we present a new fabrication method that combines for the first time popular SU-8 technology and PerMX dry-photoresist lamination for the manufacturing of high aspect ratio three-dimensional multi-level microfluidic networks. The potential of this approach, which further benefits from wafer-level manufacturing and accurate alignment of fluidic levels, is demonstrated by a highly integrated three-level microfluidic chip. The hereby achieved network complexity, including 24 fluidic vias and 16 crossing points of three individual microchannels on less than 13 mm(2) chip area, is unique for SU-8 based fluidic networks. We further report on excellent process compatibility between SU-8 and PerMX dry-photoresist which results in high interlayer adhesion strength. The tight pressure sealing of a fluidic channel (0.5 MPa for 1 h) is demonstrated for 150 μm narrow SU-8/PerMX bonding interfaces. 相似文献
53.
News reports (e.g., Abrams, 2008) and scholarly research (e.g., Wiersma & Fife, 2005) have indicated increasing concern that parent-spectator behavior at youth sport events may be problematic. Multiple strategies have been used to influence spectator behavior in youth sport contexts (e.g., "Silent Sundays"). However it is unlikely that interventions aimed at changing parent-spectator behaviors have adequately considered young athletes' perspectives, because little is known about how children want parents to behave during youth sport events. Therefore, children (ages 7-14 years) were asked to describe how parents actually behaved at youth sport events and how they wanted parents to behave. Through grounded theory analysis (Charmaz, 2000), three parent "roles" emerged from the data-supportive parent, demanding coach, and crazed fan. 相似文献
54.
A review on high power SOFC electrolyte layer manufacturing using thermal spray and physical vapour deposition technologies 总被引:1,自引:0,他引:1
Pierre Coddet Han-lin Liao Christian Coddet 《上海大学学报(英文版)》2014,(3):212-221
Manufacturing of solid oxide fuel cell (SOFC) components remains nowadays a key point for the indus- trial development of this technology. Especially, the deposition of the dense electrolyte layer which is sand- wiched between the porous anode and the porous cathode is of paramount importance and thus focuses a lot of attention. Therefore, this paper considers and reviews recent developments concerning solid electrolyte layers manufacturing using thermal spray (TS) and physical vapour deposition (PVD) technologies. 相似文献
55.
Torres-Martín César Acal Christian El-Homrani Mohammed Mingorance-Estrada Ángel C. 《Educational technology research and development : ETR & D》2022,70(3):909-929
Educational technology research and development - The objective has been to know the impact of the flipped classroom methodology on the academic performance of students during their training... 相似文献
56.
Jun Lin Wei-ying Zheng Peng-ruo-feng Liu Ning Zhang Hui-ping Lin Yi-jing Fan Xin-hua Gu Oliver Vollrath Christian Mehl 《Journal of Zhejiang University. Science. B》2014,15(7):649-660
The aim of this study is to evaluate the influence of Tooth Mousse (TM) application, smear layer removal, and storage time on resin-dentin microtensile bond strength (μTBS). Dentin specimens were divided into two groups: (1) smear layer covered; (2) smear layer removed using 15% EDTA for 90 s. In each group, half the specimens were treated once with TM for 60 min. After bonding procedures using a two-step self-etching adhesive (Clearfil SE Bond (CSE); Kuraray Medical, Tokyo, Japan), an all-in-one adhesive (G-Bond (GB); GC Corp, Tokyo, Japan), and a total-etch adhesive (Adper Single Bond 2 (SB); 3M ESPE, St. Paul, MN, USA), the specimens were stored for 3 d or 6 months in deionized water at 37 °C, and μTBS was tested and analyzed. With the exception of SB (no TM application) and GB, the μTBS was significantly increased for CSE and SB using EDTA pre-conditioning and 3 d of storage (P≤0.001). Bond strength of GB decreased significantly when using EDTA (3 d storage, P<0.05). TM application only increased the μTBS of GB (no EDTA) and SB (with EDTA) after 3 d (P≤0.02). Comparing the adhesives after 3 d of storage, CSE exhibited the greatest μTBS values followed by GB and SB (P≤0.02). The factors of adhesive, EDTA, and TM did not show any significant impact on μTBS when specimens were stored for 6 months (P>0.05). The additional application of TM and EDTA for cavity preparation seems only to have a short-term effect, and no influence on μTBS of dentin bonds after a period of 6 months. 相似文献
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58.
Objective
(1) To describe lacerations of the vaginal fornices, an injury known to be associated with consensual sexual intercourse, including known complications and treatment course, (2) to contrast these injuries with injuries sustained during sexual assault, and (3) to discuss the assessment of adolescent patients for sexual injuries.Methods
We present a case series of 4 female adolescent patients seen at a children's hospital over a period of 6 months. Each patient developed significant vaginal bleeding after sexual intercourse, and 3 of the patients presented to the emergency department with vital signs consistent with compensated shock.Results
Each patient was evaluated by pediatric surgery, and found to have a laceration of the vagina. Three of the patients described consensual intercourse prior to the onset of bleeding, and had lacerations of the vaginal fornices; these patients were determined to have injuries resulting from consensual sexual intercourse. The fourth patient reported sexual assault as the cause of her injuries, and was treated for longitudinal lacerations of the vaginal wall.Conclusions
Lacerations of the upper vagina are not frequently reported in forced vaginal intercourse, but are occasionally reported as injuries sustained during consensual coitus. In the absence of reported sexual assault, a severe vaginal fornix laceration is consistent with the diagnosis of coital injury from consensual intercourse. Diagnosis and treatment of this injury can be delayed due to the sensitive nature of these injuries. Bleeding can be profuse, leading to hemorrhagic shock, and these injuries may require transfusion of blood products and surgical repair in some cases. Complications may include hemoperitoneum, pneumoperitoneum, or retroperitoneal hematoma, even in the absence of complete vaginal perforation.Practice implications
Knowledge of the consensual sexual injuries that may occur in adolescent patients can guide diagnosis, treatment, and counseling for the patient and her family, preventing long-term medical complications and legal consequences. 相似文献59.
60.
Anne Focke Sina Spancken Christian Stockinger Benjamin Thürer Thorsten Stein 《European Journal of Sport Science》2016,16(7):787-793
Benefits of bilateral practice both for the non-dominant and for the dominant body side have been shown in several studies. Thereby, most of the studies included movement tasks of the upper extremity or investigated sports games in which the ability of acting bilaterally is an essential basis for success and, thus, a bilateral practice is reasonable anyway. Individual unilaterally performed sports including movement tasks of the lower extremity are rarely investigated. Therefore, the aim of our study was to test if contralateral transfer due to bilateral practice can be found in an unilaterally performed sport including the lower extremity. We trained and tested 61 adolescent athletes in long jump to compare the jumping performance of the dominant leg after a 12-week practice period between two groups: a bilateral practice group that practiced specific long jump exercises with both the dominant and non-dominant leg and an unilateral practice group that practiced specific long jump exercises only with the dominant leg. Results showed a superior effect of bilateral practice compared to unilateral practice regarding the jumping performance of the dominant leg. The performance increase at post-test and retention-test for the dominant limb was significantly higher for the bilateral practice group (pre-to-post: 5.2%, pre-to-retention: 7.4%) compared to the unilateral practice group (pre-to-post: 3.4%, pre-to-retention: 4.5%). Thus, bilateral practice should be established in the early practice programmes of track and field athletes to improve the performance of the dominant take-off leg. 相似文献