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Izzet Altun Jingjie Hu Hassan Albadawi Zefu Zhang Marcela A. Salomao Joseph L. Mayer Leila Jamal Rahmi Oklu 《Advanced materials (Deerfield Beach, Fla.)》2020,32(52):2005603
Vascular embolization is a life-saving minimally invasive catheter-based procedure performed to treat bleeding vessels. Through these catheters, numerous metallic coils are often pushed into the bleeding artery to stop the blood flow. While there are numerous drawbacks to coil embolization, physician expertise, availability of these coils, and their costs further limit their use. Here, a novel blood-derived embolic material (BEM) with regenerative properties, that can achieve instant and durable intra-arterial hemostasis regardless of coagulopathy, is developed. In a large animal model of vascular embolization, it is shown that the BEM can be prepared at the point-of-care within 26 min using fresh blood, it can be easily delivered using clinical catheters to embolize renal and iliac arteries, and it can achieve rapid hemostasis in acutely injured vessels. In swine arteries, the BEM increases cellular proliferation, angiogenesis, and connective tissue deposition, suggesting vessel healing and durable vessel occlusion. The BEM has significant advantages over embolic materials used today, making it a promising new tool for embolization. 相似文献
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Lucas de Souza Nespeca Hellen Fernanda da Silva Paulino Tamires Barlati Vieira da Silva Evandro Bona Fernanda Vitória Leimann Leila Larisa Medeiros Marques Flávia Aparecida Reitz Cardoso Adriana Aparecida Droval Renata Hernandez Barros Fuchs 《International Journal of Food Science & Technology》2021,56(4):2019-2029
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Rotheram-Borus Mary Jane; Lester Patricia; Song Juwon; Lin Ying-Ying; Leonard Noelle R.; Beckwith Leila; Ward Mary J.; Sigman Marian; Lord Lynwood 《Canadian Metallurgical Quarterly》2006,74(3):622
The longitudinal impact of a family-based intervention on grandchildren of parents with HIV (PWH) is evaluated. Because PWH and their daughters demonstrated gains over 6 years when randomized to a coping skills intervention compared with a control condition, the adjustment of the PWH's grandchildren was also compared across conditions. Grandchildren in the intervention condition reported significantly fewer internalizing and externalizing behavioral symptoms compared with grandchildren in the control condition. There is weak evidence that grandchildren in the intervention condition had higher scores on measures of cognitive development and more positive home environments. These results suggest that there are possibly long-term, intergenerational benefits of an intervention for families coping with HIV. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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We designed two experiments to examine the influence of a group decision on subjects' estimates of the attitudes of group members. In Experiment 1, subjects were led to believe that their initial vote in a jury decision-making task either agreed or disagreed with the majority vote and, independently of agreement with the majority, that their vote either agreed or disagreed with the final group decision. Subjects' own attitudes changed in the direction of the majority position only when the group decision was inconsistent with their initial vote. Consistent with prior research on the group attribution error, subjects inferred a correspondence between the final group decision and the other jurors' attitudes about the guilt or innocence of the defendant. In Experiment 2, subjects actively participated in or passively observed a group decision that either had or did not have direct consequences for the voting group. We found evidence of the group attribution error in both active participants' and passive observers' inferences about the attitudes of group members. Moreover, subjects tended to infer correspondence between the decision and the attitudes of voting members only when the decision had no immediate consequences for the group. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Concurs with R. E. Fancher (see record 1987-31600-001) that the badly retouched photographs in H. H. Goddard's (1912) study of heredity in the Kallikak family were not a fraudulent attempt to make the mentally retarded Ss look sinister or diabolical. The need to interpret historical documents in their multidimensional sociological context is noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Control of Grid Connected Photovoltaic Systems with Microinverters: New Theoretical Design and Numerical Evaluation
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Abdelhafid Yahya Hassan El Fadil Mustapha Oulcaid Leila Ammeh Fouad Giri Josep M. Guerrero 《Asian journal of control》2018,20(2):906-918
This paper addresses the problem of controlling grid connected photovoltaic (PV) systems that are driven with microinverters. The systems to be controlled consist of a solar panel, a boost dc–dc converter, a DC link capacitor, a single‐phase full‐bridge inverter, a filter inductor, and an isolation transformer. We seek controllers that are able to simultaneously achieve four control objectives, namely: (i) asymptotic stability of the closed loop control system; (ii) maximum power point tracking (MPPT) of the PV module; (iii) tight regulation of the DC bus voltage; and (iv) unity power factor (PF) in the grid. To achieve these objectives, a new multiloop nonlinear controller is designed using the backstepping design technique. A key feature of the control design is that it relies on an averaged nonlinear system model accounting, on the one hand, for the nonlinear dynamics of the underlying boost converter and inverter and, on the other, for the nonlinear characteristic of the PV panel. To achieve the MPPT objective, a power optimizer is designed that computes online the optimal PV panel voltage used as a reference signal by the PV voltage regulator. It is formally shown that the proposed controller meets all the objectives. This theoretical result is confirmed by numerical simulation tests. 相似文献