217 research outputs found

    View Synthesis of Dynamic Scenes based on Deep 3D Mask Volume

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    Image view synthesis has seen great success in reconstructing photorealistic visuals, thanks to deep learning and various novel representations. The next key step in immersive virtual experiences is view synthesis of dynamic scenes. However, several challenges exist due to the lack of high-quality training datasets, and the additional time dimension for videos of dynamic scenes. To address this issue, we introduce a multi-view video dataset, captured with a custom 10-camera rig in 120FPS. The dataset contains 96 high-quality scenes showing various visual effects and human interactions in outdoor scenes. We develop a new algorithm, Deep 3D Mask Volume, which enables temporally-stable view extrapolation from binocular videos of dynamic scenes, captured by static cameras. Our algorithm addresses the temporal inconsistency of disocclusions by identifying the error-prone areas with a 3D mask volume, and replaces them with static background observed throughout the video. Our method enables manipulation in 3D space as opposed to simple 2D masks, We demonstrate better temporal stability than frame-by-frame static view synthesis methods, or those that use 2D masks. The resulting view synthesis videos show minimal flickering artifacts and allow for larger translational movements

    Effectiveness of laparoscopic sleeve gastrectomy for weight loss and obesity-associated co-morbidities: a 3-year outcome from Mainland Chinese patients

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    AbstractBackgroundLaparoscopic sleeve gastrectomy (LSG) is becoming a stand-alone bariatric surgery for obesity, but its effectiveness for Mainland Chinese patients remains unclear.ObjectivesTo evaluate the effectiveness and safety of LSG for Mainland Chinese patientsSettingA tertiary hospitalMethodsRetrospective analysis of patients admitted for LSG between January 2011 and February 2012 was performed. Medium-term outcome measures were: total weight loss (%TWL), excess weight loss (%EWL), co-morbidities, improvement, and complications.ResultsSeventy patients (body mass index [BMI] 40.8±5.9 kg/m2) underwent LSG, comprising 40 women and 30 men. The most common co-morbidity was diabetes (n = 29, 41.4%). Lost to follow-up rate for weight loss was 15.7%, 31.4%, and 41% at 1, 2, and 3 years. The %TWL was 34.4±6.1, 34.7±6.2 and 33.7±7.1 at 1, 2, and 3 years. The %EWL increased to 77.1±13.0, 77.9±12.2 and 77.2±13.1 at 1, 2, and 3years. The proportions of patients having successful weight loss were 100% or 85% at 3 years according the definition of %TWL>10% or %EWL>50%. Approximately 79.3%, 51.7%, and 44.8% of patients completed follow-up for glycemic control at each time point, respectively. The proportions of patients with optimal glycemic control (fasting blood glucose [FBG]<5.6 mmol/L; hemoglobin A1C [HbA1C]<6.5%) were 47.9%, 60.0%, and 69.2% at 1, 2, and 3years. The weight loss and glycemic control effect may be greater in the high BMI group (≥40 kg/m2). Early and late complications occurred in 8.6% and 7.1% of patients during follow-up.ConclusionsLSG is effective in weight loss and glycemic control and is safe for Mainland Chinese obese patients, especially for patients with a BMI≥40 kg/m2

    Neural Free-Viewpoint Relighting for Glossy Indirect Illumination

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    Precomputed Radiance Transfer (PRT) remains an attractive solution for real-time rendering of complex light transport effects such as glossy global illumination. After precomputation, we can relight the scene with new environment maps while changing viewpoint in real-time. However, practical PRT methods are usually limited to low-frequency spherical harmonic lighting. All-frequency techniques using wavelets are promising but have so far had little practical impact. The curse of dimensionality and much higher data requirements have typically limited them to relighting with fixed view or only direct lighting with triple product integrals. In this paper, we demonstrate a hybrid neural-wavelet PRT solution to high-frequency indirect illumination, including glossy reflection, for relighting with changing view. Specifically, we seek to represent the light transport function in the Haar wavelet basis. For global illumination, we learn the wavelet transport using a small multi-layer perceptron (MLP) applied to a feature field as a function of spatial location and wavelet index, with reflected direction and material parameters being other MLP inputs. We optimize/learn the feature field (compactly represented by a tensor decomposition) and MLP parameters from multiple images of the scene under different lighting and viewing conditions. We demonstrate real-time (512 x 512 at 24 FPS, 800 x 600 at 13 FPS) precomputed rendering of challenging scenes involving view-dependent reflections and even caustics.Comment: 13 pages, 9 figures, to appear in cgf proceedings of egsr 202

    Plasmoid ejection and secondary current sheet generation from magnetic reconnection in laser-plasma interaction

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    Reconnection of the self-generated magnetic fields in laser-plasma interaction was first investigated experimentally by Nilson {\it et al.} [Phys. Rev. Lett. 97, 255001 (2006)] by shining two laser pulses a distance apart on a solid target layer. An elongated current sheet (CS) was observed in the plasma between the two laser spots. In order to more closely model magnetotail reconnection, here two side-by-side thin target layers, instead of a single one, are used. It is found that at one end of the elongated CS a fan-like electron outflow region including three well-collimated electron jets appears. The (>1>1 MeV) tail of the jet energy distribution exhibits a power-law scaling. The enhanced electron acceleration is attributed to the intense inductive electric field in the narrow electron dominated reconnection region, as well as additional acceleration as they are trapped inside the rapidly moving plasmoid formed in and ejected from the CS. The ejection also induces a secondary CS

    ABL Genomic Editing Sufficiently Abolishes Oncogenesis of Human Chronic Myeloid Leukemia Cells In Vitro and In Vivo

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    Chronic myelogenous leukemia (CML) is the most common type of leukemia in adults, and more than 90% of CML patients harbor the abnormal Philadelphia chromosome (Ph) that encodes the BCR-ABL oncoprotein. Although the ABL kinase inhibitor (imatinib) has proven to be very effective in achieving high remission rates and improving prognosis, up to 33% of CML patients still cannot achieve an optimal response. Here, we used CRISPR/Cas9 to specifically target the BCR-ABL junction region in K562 cells, resulting in the inhibition of cancer cell growth and oncogenesis. Due to the variety of BCR-ABL junctions in CML patients, we utilized gene editing of the human ABL gene for clinical applications. Using the ABL gene-edited virus in K562 cells, we detected 41.2% indels in ABL sgRNA_2-infected cells. The ABL-edited cells reveled significant suppression of BCR-ABL protein expression and downstream signals, inhibiting cell growth and increasing cell apoptosis. Next, we introduced the ABL gene-edited virus into a systemic K562 leukemia xenograft mouse model, and bioluminescence imaging of the mice showed a significant reduction in the leukemia cell population in ABL-targeted mice, compared to the scramble sgRNA virus-injected mice. In CML cells from clinical samples, infection with the ABL gene-edited virus resulted in more than 30.9% indels and significant cancer cell death. Notably, no off-target effects or bone marrow cell suppression was found using the ABL gene-edited virus, ensuring both user safety and treatment efficacy. This study demonstrated the critical role of the ABL gene in maintaining CML cell survival and tumorigenicity in vitro and in vivo. ABL gene editing-based therapy might provide a potential strategy for imatinib-insensitive or resistant CML patient

    بررسی حیطه‌های موجود در فرم‌های ارزشیابی از دیدگاه دانشجویان در دانشگاه علوم پزشکی زنجان در سال تحصیلی 86- 87

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    زمینه و هدف: ارزشیابی استادان متداول‌ترین روش جهت سنجش کیفیت آموزش می‌باشد. دانشجویان بیش از دست‌اندرکاران در جریان روند آموزش قرار‌دارند بنابراین با نظرخواهی از آنان دیدگاه کاملی برای مسئولین در مورد نقاط قوت و ضعف استادان به‌دست می‌آید. هدف از این پژوهش بررسی حیطه‌های موجود در فرم‌های ارزشیابی از دیدگاه دانشجویان در دانشکده‌های پزشکی، پیراپزشکی و پرستاری و مامایی می‌باشد. روش بررسی: این تحقیق به صورت توصیفی انجام گرفت. 1683 برگ ارزشیابی دانشجویان از استادان هیأت علمی (73 نفر) مربوط به دانشکده‌های پزشکی، پیراپزشکی و پرستاری- مامایی بررسی شد. پرسش‌نامه‌ی دانشجویان پزشکی حاوی 15 سؤوال و دانشجویان پیراپزشکی و پرستاری مامایی 21 سؤوال بود که بر اساس مقیاس لیکرات از حیطه‌های مختلف مقرراتی، علمی و آموزشی، نظارتی و نگرشی تشکیل شده بود. نمرات سؤوالات از نمره‌ی 100 محاسبه شد، نمرات بالاتر بیانگر عملکرد مطلوب‌تراستادان می‌باشد. تجزیه و تحلیل داده‌ها به‌صورت آمار توصیفی با نرم‌افزار SPSS انجام شد. یافته‌ها: نتایج نشان داد مقایسه در سطوح کلی بین دانشکده‌ها، دانشکده‌ی پیراپزشکی با میانگین کل و انحراف معیار 61/3 ±50/85 نسبت به سایر دانشکده‌ها برتری دارد. دانشکده‌ی پیراپزشکی در حیطه‌ی مقرراتی با میانگین و انحراف معیار 89/3±01/91، دانشکده‌ی پزشکی در حیطه‌ی نگرشی با میانگین و انحراف معیار 45/5±48/90 و دانشکده‌ی پرستاری مامایی در حیطه‌ی مقرراتی با میانگین و انحراف معیار 25/4±34/88 بیشترین امتیاز را داشتند. نتیجه‌نهایی نشان می‌دهد، حیطه‌ی علمی و آموزشی نسبت به سایر حیطه‌ها در سطح پایین‌تر می‌باشد. نتایج حیطه‌ها (علمی و آموزشی، نظارتی و نگرشی) بین دانشکده‌ها معنی‌دار می‌باشد (0001/0=P). نتیجه‌گیری: به نظر می‌رسد با برنامه‌ریزی جهت برگزاری کارگاه‌های آموزشی، روش تدریس و تحقیق جهت ارتقای آموزش استادان، اعطا‌ی فرصت مطالعاتی و تشویق انجام کارهای تحقیقاتی و پژوهشی گام مؤثری جهت ارتقای سطح علمی و بالاخره عملکرد بالای استادان خواهد بود
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