75 research outputs found

    Understanding Early Childhood Engineering Interest Development as a Family-Level Systems Phenomenon: Findings from the Head Start on Engineering Project

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    There is growing recognition that interest is critical for engaging and supporting learners from diverse communities in engineering and other science, technology, engineering, and mathematics (STEM) topics. Although interest research has historically focused on older children, studies demonstrate that preschool-age and younger children also develop persistent, individualized interests in different objects, activities, and topics and that these early interests have important implications for ongoing learning and development. Unfortunately, there is relatively little research on engineering learning in early childhood and almost no work specific to the concept of interest. To begin to address this need, we conducted in-depth case study research with 15 English- and Spanish-speaking families and their preschool-age children participating in a family-based engineering education program through a local Head Start organization. Using systems theory to conceptualize interest development as involving the whole family, the study documented how both children and parents developed engineering-related interests through the program and explored the characteristics of and shifts in these interest systems. The qualitative, cross-case analysis highlighted three aspects of family-level interest development that varied across families and over time: (1) parent awareness, knowledge, and values; (2) family re-engagement with engineering activities; and (3) family use of the engineering design process. Shifts were also observed in a subset of the families that potentially signal movement toward deeper, sustained levels of engineering-related interest

    Pauli's Principle in Probe Microscopy

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    Exceptionally clear images of intramolecular structure can be attained in dynamic force microscopy through the combination of a passivated tip apex and operation in what has become known as the "Pauli exclusion regime" of the tip-sample interaction. We discuss, from an experimentalist's perspective, a number of aspects of the exclusion principle which underpin this ability to achieve submolecular resolution. Our particular focus is on the origins, history, and interpretation of Pauli's principle in the context of interatomic and intermolecular interactions.Comment: This is a chapter from "Imaging and Manipulation of Adsorbates using Dynamic Force Microscopy", a book which is part of the "Advances in Atom and Single Molecule Machines" series published by Springer [http://www.springer.com/series/10425]. To be published late 201

    Analysis and Suggestions for Business Model of eBayEachnet

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    EBAYæ˜“è¶Łçœ‘ć’Œæ·˜ćźçœ‘æ˜Żç›źć‰äž­ć›œç””ć­ć•†ćŠĄäž­ç»ćžžèą«æćŠçš„äž€äžȘćŻčæ‰‹ă€‚2002ćčŽæ—¶ïŒŒEBAYæ˜“è¶Łæ›Ÿç»äž€æžç‹Źç§€ïŒŒäœ†ćœšæ·˜ćźçœ‘ć’Œæ‹æ‹çœ‘çš„ç«žäș‰äž‹ïŒŒèż…é€Ÿäž§ć€±ćž‚ćœșéą†ć…ˆćœ°äœïŒŒćž‚ćœșä»œéąé€æ­„çŒ©ć°ïŒŒćč¶ç»ˆäșŽäžŽTOMé›†ć›ąæœ‰é™ć…Źćžäž‹ć±žçš„TOM朹çșżæˆç«‹äș†ćˆè„慬揾。 æœŹæ–‡äž»èŠèżç”šçżć›ć„•æ•™æŽˆçš„ă€Šć•†äžšæšĄćŒćˆ›æ–°ă€‹ç†èźșïŒŒä»„ćˆè„ć…Źćžçš„æˆç«‹äžș研究æˆȘæ­ąæ—¶é—ŽïŒŒć°èŻ•æ­ç€șă€ćˆ†æžă€è§Łé‡ŠEBAYæ˜“è¶Łć•†ćŠĄæšĄćŒé’ˆćŻčäž­ć›œć€§é™†ćž‚ćœșè€Œèš€ć­˜ćœšçš„äžè¶łäč‹ć€„ćč¶æć‡șćźžçŽ°èœŹæœșçš„è‹„ćčČć»șèźźă€‚ć…šæ–‡ć…±ćˆ†äș”ç« ïŒŒćˆ†ćˆ«ćŠ‚äž‹ïŒš çŹŹäž€ç« äž»èŠä»‹ç»èźșæ–‡ć†™äœœçš„èƒŒæ™Żć’Œç ”ç©¶æ„äč‰æ‰€ćœšïŒŒä»„ćŠç ”ç©¶ç†èźșć’ŒæĄ†æž¶ă€‚ 珏äșŒç« é’ˆćŻčEBAYæ˜“è¶Łć•†ćŠĄæšĄćŒïŒŒæŒ‰ç…§ć•†äžšæšĄćŒćˆ›æ–°ç†èźșçš„ć±‚æŹĄïŒŒä»Žć•†ćŠĄæšĄćŒçŽŻćąƒă€ć•†ćŠĄæšĄćŒèŠçŽ ă€...eBayEachnet and Taobao are main competitors in China’s E-commerce. eBayEachnet just took the lead in as earlier as year 2002, however, it was overwhelmed by Taobao and Paipai gradually, the leading was lost and the share market diminished very soon, as a result, it incorporated with Tom Online, a filial of Tom group limited company.Bearing in mind the theory of <Business Models Innovatio...ć­ŠäœïŒšć·„ć•†çźĄç†çĄ•ćŁ«é™ąçł»äž“äžšïŒšçźĄç†ć­Šé™ąć·„ć•†çźĄç†æ•™è‚Čäž­ćżƒïŒˆMBAäž­ćżƒïŒ‰_淄敆知理祕棫(MBA)ć­Šć·ïŒš20041523

    Effects of Once-Weekly Exenatide on Cardiovascular Outcomes in Type 2 Diabetes.

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    Abstract BACKGROUND: The cardiovascular effects of adding once-weekly treatment with exenatide to usual care in patients with type 2 diabetes are unknown. METHODS: We randomly assigned patients with type 2 diabetes, with or without previous cardiovascular disease, to receive subcutaneous injections of extended-release exenatide at a dose of 2 mg or matching placebo once weekly. The primary composite outcome was the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. The coprimary hypotheses were that exenatide, administered once weekly, would be noninferior to placebo with respect to safety and superior to placebo with respect to efficacy. RESULTS: In all, 14,752 patients (of whom 10,782 [73.1%] had previous cardiovascular disease) were followed for a median of 3.2 years (interquartile range, 2.2 to 4.4). A primary composite outcome event occurred in 839 of 7356 patients (11.4%; 3.7 events per 100 person-years) in the exenatide group and in 905 of 7396 patients (12.2%; 4.0 events per 100 person-years) in the placebo group (hazard ratio, 0.91; 95% confidence interval [CI], 0.83 to 1.00), with the intention-to-treat analysis indicating that exenatide, administered once weekly, was noninferior to placebo with respect to safety (P<0.001 for noninferiority) but was not superior to placebo with respect to efficacy (P=0.06 for superiority). The rates of death from cardiovascular causes, fatal or nonfatal myocardial infarction, fatal or nonfatal stroke, hospitalization for heart failure, and hospitalization for acute coronary syndrome, and the incidence of acute pancreatitis, pancreatic cancer, medullary thyroid carcinoma, and serious adverse events did not differ significantly between the two groups. CONCLUSIONS: Among patients with type 2 diabetes with or without previous cardiovascular disease, the incidence of major adverse cardiovascular events did not differ significantly between patients who received exenatide and those who received placebo. (Funded by Amylin Pharmaceuticals; EXSCEL ClinicalTrials.gov number, NCT01144338 .)

    31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

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    Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570
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