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11.
Objective:To review our experience of the treatment of bilateral primary spontaneous pneumothorax (PSP) by video-assisted thoracoscopic surgery (VATS). Materials and methods: Retrospective chart review was followed by an on-clinic or telephone interview. Patients were cared for by one thoracic surgeon in four medical centers or community hospitals in Northern and Central Taiwan. Thirteen patients with bilateral PSP underwent bilateral VATS simultaneously or sequentially from July 1994 to December 2005. Results: Twelve males and one female, with age ranging from 15 to 36 years (mean 23.1 years), were treated with VATS for bilateral PSP, under the indications of bilateral pneumothoracis simultaneously (n=4) or sequentially (n=9). The interval between the first and second contra-lateral VATS procedure for non-simultaneous PSP patients ranged from 7 d to 6 years. Eleven of 13 patients (84.6%) had prominent pulmonary bullae/blebs, and underwent bullae resection with mechanical or chemical pleurodesis. The mean operative time was (45.6±18.3) min (range 25-96 min) and (120.6±28.7) min (range 84-166 min) respectively for the non-simultaneous (second VATS for the recurrence of contralateral side after first VATS) and simultaneous (bilateral VATS in one operation) procedures. There was no postoperative mortality. However, prolonged air leakage (>7 d) occurred in one patient (7.7%) who recovered after conservative treatment. The mean duration of chest tube drainage was 3.1 d and the median follow up period was 3.4 years. Conclusions: VATS is a safe and effective procedure in the treatment of bilateral PSP. Bilateral VATS is only recommended for patients with simultaneously bilateral PSP, because the incidence of recurrence, even with visible bullae, was not so high in my group and in some previous literature. Bilateral VATS in a supine position should only be used in selective cases, because of possible pleural adhesion or hidden bullae on the posterior side.  相似文献   
12.
Primary–secondary school transition encompasses multiple social, academic and environmental changes which can negatively impact children’s emotional well-being. Children with Social, Emotional and Mental Health difficulties (SEMH) are believed to be especially vulnerable during this time. However, the voices of children with SEMH are heavily underrepresented in this field within practice and research. The present case study examined how children with SEMH difficulties within one special school experience primary–secondary school transition and how they are supported, in order to make recommendations to improve this period. The case study was qualitative and longitudinal, conducted over 18-months and methodologies included ethnographic observations, child photo-elicitation focus groups (with 11 Year 6 children) and three adult interviews. Findings demonstrated that over primary–secondary school transition children with SEMH difficulties (a) negotiate significant structural changes in support (often unanticipated) and (b) need to feel a sense of safety and belonging. To manage this effectively, transition provision for children with SEMH difficulties needs to consider their short-term emotional well-being whilst still in primary school, in addition to their long-term well-being looking ahead to secondary school. Greater collaboration and communication across schools and stakeholders can help ensure children receive continuity in standards and support.  相似文献   
13.
Most youth in juvenile delinquent systems end up incarcerated due in part to poor decision-making skills. This study describes a theoretical framework undergirding the relationships across delinquency, learning climate, decision-making, and computational logic. This framework will inform a team of educators, criminologists, and psychologists, and their peers in computer science and mathematics, instructional software design, and content experts as they build and test an innovative instructional model for youth in secure care settings. The goal of the system is to improve human decision-making skills, while preparing youth for further education potentially leading to careers in STEM fields.  相似文献   
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The study explored how to best use scaffolds for supporting students’ inquiry practices in computer-supported learning environments. We designed a series of inquiry units assisted with three versions of written inquiry prompts (generic and context-specific); that is, three scaffold-fading conditions: implicit, explicit, and fading. We then examined how the three scaffold-fading conditions influenced students’ conceptual understanding, understanding of scientific inquiry, and inquiry abilities. Three grade-10 classes (N?=?105) participated in this study; they were randomly assigned to and taught in the three conditions. Data-collection procedures included a pretest–posttest approach and in-depth observations of the target students. The findings showed that after these inquiry units, all of the students exhibited significant learning gains in conceptual knowledge and performed better inquiry abilities regardless of which condition was used. The explicit and fading conditions were more effective in enhancing students’ understanding of scientific inquiry. The fading condition tended to better support the students’ development of inquiry abilities and help transfer these abilities to a new setting involving an independent socioscientific task about where to build a dam. The results suggest that fading plays an essential role in enhancing the effectiveness of scaffolds.  相似文献   
16.
Accurate teacher evaluations of student performance are crucial for effective teaching. This study examined whether students’ immigration and language background affect teachers’ evaluations. Multilevel analyses tested whether teachers overestimate the performance of immigrant relative to that of non-immigrant students. As part of the German PISA 2003 assessment, 305 teachers predicted the performance of seven of their students on two mathematics problems of different linguistic complexity. Results revealed an interaction effect of students’ language background and linguistic complexity of the problem on teachers’ predictions. Teachers overestimated the performance of bilingual students more than the performance of monolingual immigrant or non-immigrant students on a linguistically complex problem. Teachers need to consider both students’ language background and linguistic demands of the material used to appropriately support bilingual students.  相似文献   
17.
Knowledge management systems (KMSs) support high-quality services while shaping and improving positioning of services. Given such strategic importance of KMS, this study explores the effects of different types of KMS, which respond to the attributes (i.e., diversity and tacitness) of collective knowledge, on service (re-)positioning. Through a case study of a financial consulting company at the core of KMSs, combinations of the two knowledge attributes are used to determine which type of KMS (i.e., information library, deepened stock, thought islands, and shared brain) offers the greatest efficiency and effectiveness in service (re-)positioning. The joint concerns of service innovation scope and specificity are also considered. Finally, the study discusses the theoretical and practical implications on KMS design and functionality in the new business age of service innovation.  相似文献   
18.
The poor solubility of many newly discovered drugs has resulted in numerous challenges for the time-controlled release of therapeutics. In this study, an advanced drug delivery platform to encapsulate and deliver hydrophobic drugs, consisting of poly (lactic-co-glycolic acid) (PLGA) nanoparticles incorporated within poly (ethylene glycol) (PEG) microgels, was developed. PLGA nanoparticles were used as the hydrophobic drug carrier, while the PEG matrix functioned to slow down the drug release. Encapsulation of the hydrophobic agents was characterized by fluorescence detection of the hydrophobic dye Nile Red within the microgels. In addition, the microcomposites prepared via the droplet-based microfluidic technology showed size tunability and a monodisperse size distribution, along with improved release kinetics of the loaded cargo compared with bare PLGA nanoparticles. This composite system has potential as a universal delivery platform for a variety of hydrophobic molecules.  相似文献   
19.
A vital aspect affecting the success rate of in vitro fertilization is the culture environment of the embryo. However, what is not yet comprehensively understood is the affect the biochemical, physical, and genetic requirements have over the dynamic development of human or mouse preimplantation embryos. The conventional microdrop technique often cultures embryos in groups, which limits the investigation of the microenvironment of embryos. We report an open microwell platform, which enables micropipette manipulation and culture of embryos in defined sub-microliter volumes without valves. The fluidic environment of each microwell is secluded from others by layering oil on top, allowing for non-invasive, high-resolution time-lapse microscopy, and data collection from each individual embryo without confounding factors. We have successfully cultured mouse embryos from the two-cell stage to completely hatched blastocysts inside microwells with an 89% success rate (n = 64), which is comparable to the success rate of the contemporary practice. Development timings of mouse embryos that developed into blastocysts are statistically different to those of embryos that failed to form blastocysts (p–value < 10−10, two-tailed Student''s t-test) and are robust indicators of the competence of the embryo to form a blastocyst in vitro with 94% sensitivity and 100% specificity. Embryos at the cleavage- or blastocyst-stage following the normal development timings were selected and transferred to the uteri of surrogate female mice. Fifteen of twenty-two (68%) blastocysts and four of ten (40%) embryos successfully developed into normal baby mice following embryo transfer. This microwell platform, which supports the development of preimplanted embryos and is low-cost, easy to fabricate and operate, we believe, opens opportunities for a wide range of applications in reproductive medicine and cell biology.  相似文献   
20.
Recent advances in microscale flow propulsion through bioinspired artificial cilia provide a promising alternative for lab-on-a-chip applications. However, the ability of actuating artificial cilia to achieve a time-dependent local flow control with high accuracy together with the elegance of full integration into the biocompatible microfluidic platforms remains remote. Driven by this motive, the current work has constructed a series of artificial cilia inside a microchannel to facilitate the time-dependent flow propulsion through artificial cilia actuation with high-speed (>40 Hz) circular beating behavior. The generated flow was quantified using micro-particle image velocimetry and particle tracking with instantaneous net flow velocity of up to 101 μm/s. Induced flow patterns caused by the tilted conical motion of artificial cilia constitutes efficient fluid propulsion at microscale. This flow phenomenon was further measured and illustrated by examining the induced flow behavior across the depth of the microchannel to provide a global view of the underlying flow propulsion mechanism. The presented analytic paradigms and substantial flow evidence present novel insights into the area of flow manipulation at microscale.  相似文献   
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