50 research outputs found

    Scientific Computing in the Soviet Union

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    In the last decade, the Soviet Union has placed increased emphasis on the development of high-speed computers and networks for use in scientific, economic, and military applications. When Communist Party General Secretary Mikhail Gorbachev labeled supercomputer development a top priority task for our science and economy in April, 1987, he added new urgency to the production of machines that would both support activities in these applications and also serve as high-profile standard-bearers for perestroika, his program of restructuring and modernization for the nation. The Soviets have also undertaken some major projects in networking, including the creation of a nationwide packet-switched network for the Academy of Sciences, work on network access to databases on scientific literature, and local area networks at a number of institutes

    Cost-effectiveness of total neoadjuvant therapy with short-course radiotherapy for resectable locally advanced rectal cancer

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    Importance: Short-course radiotherapy and total neoadjuvant therapy (SCRT-TNT) followed by total mesorectal excision (TME) has emerged as a new treatment paradigm for patients with locally advanced rectal adenocarcinoma. However, the economic implication of this treatment strategy has not been compared with that of conventional long-course chemoradiotherapy (LCCRT) followed by TME with adjuvant chemotherapy. Objective: To perform a cost-effectiveness analysis of SCRT-TNT vs LCCRT in conjunction with TME for patients with locally advanced rectal cancer. Design, Setting, and Participants: A decision analytical model with a 5-year time horizon was constructed for patients with biopsy-proven, newly diagnosed, primary locally advanced rectal adenocarcinoma treated with SCRT-TNT or LCCRT. Markov modeling was used to model disease progression and patient survival after treatment in 3-month cycles. Data on probabilities and utilities were extracted from the literature. Costs were evaluated from the Medicare payer\u27s perspective in 2020 US dollars. Sensitivity analyses were performed for key variables. Data were collected from October 3, 2020, to January 20, 2021, and analyzed from November 15, 2020, to April 25, 2021. Exposures: Two treatment strategies, SCRT-TNT vs LCCRT with adjuvant chemotherapy, were compared. Main Outcomes and Measures: Cost-effectiveness was evaluated using the incremental cost-effectiveness ratio and net monetary benefits. Effectiveness was defined as quality-adjusted life-years (QALYs). Both costs and QALYs were discounted at 3% annually. Willingness-to-pay threshold was set at 50 000/QALY.Results:Duringthe5−yearhorizon,thetotalcostwas50 000/QALY. Results: During the 5-year horizon, the total cost was 41 355 and QALYs were 2.21 for SCRT-TNT; for LCCRT, the total cost was 54 827andQALYswere2.12,resultinginanegativeincrementalcost−effectivenessratio(−54 827 and QALYs were 2.12, resulting in a negative incremental cost-effectiveness ratio (-141 256.77). The net monetary benefit was 69 300forSCRT−TNTand69 300 for SCRT-TNT and 51 060 for LCCRT. Sensitivity analyses using willingness to pay at 100 000/QALYand100 000/QALY and 150 000/QALY demonstrated the same conclusion. Conclusions and Relevance: These findings suggest that SCRT-TNT followed by TME incurs lower cost and improved QALYs compared with conventional LCCRT followed by TME and adjuvant chemotherapy. These data offer further rationale to support SCRT-TNT as a novel cost-saving treatment paradigm in the management of locally advanced rectal cancer

    Impact of a ring fitted cap on insertion time and adenoma detection: a randomized controlled trial

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    Background and Aims: Devices for flattening colon folds can improve polyp detection at colonoscopy. However, there are few data on the endoscopic ring fitted cap (EndoRings, EndoAid, Caesarea, Israel). We sought to compare adenoma detection with EndoRings with that of standard high-definition colonoscopy. Methods: A single-center randomized controlled trial of 562 patients (284 randomized to EndoRings and 278 to standard colonoscopy) at 2 outpatient endoscopy units in the Indiana University Hospital system. Adenoma detection was the primary outcome measured as adenoma detection rate (ADR) and adenomas per colonoscopy (APC). We also compared sessile serrated polyp detection rate (SSPDR), insertion times, withdrawal times, and ease of passage through the sigmoid colon. Results: EndoRings was superior to standard colonoscopy in terms of APC (1.46 vs 1.06, p=0.025) but there were no statistically significant differences in ADR or SSPDR. Mean withdrawal time (in patients with no polyps) was shorter and insertion time (all patients) was longer in the EndoRings arm by 1.8 minutes and 0.75 minutes, respectively. One provider had significantly higher detection with EndoRings and contributed substantially to the overall results. Conclusions: EndoRings can increase adenoma detection without significant increase in procedure time, but the effect varies between operators. EndoRings slows colonoscope insertion

    Enabling real-time multi-messenger astrophysics discoveries with deep learning

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    Multi-messenger astrophysics is a fast-growing, interdisciplinary field that combines data, which vary in volume and speed of data processing, from many different instruments that probe the Universe using different cosmic messengers: electromagnetic waves, cosmic rays, gravitational waves and neutrinos. In this Expert Recommendation, we review the key challenges of real-time observations of gravitational wave sources and their electromagnetic and astroparticle counterparts, and make a number of recommendations to maximize their potential for scientific discovery. These recommendations refer to the design of scalable and computationally efficient machine learning algorithms; the cyber-infrastructure to numerically simulate astrophysical sources, and to process and interpret multi-messenger astrophysics data; the management of gravitational wave detections to trigger real-time alerts for electromagnetic and astroparticle follow-ups; a vision to harness future developments of machine learning and cyber-infrastructure resources to cope with the big-data requirements; and the need to build a community of experts to realize the goals of multi-messenger astrophysics

    Case Reports1. A Late Presentation of Loeys-Dietz Syndrome: Beware of TGFβ Receptor Mutations in Benign Joint Hypermobility

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    Background: Thoracic aortic aneurysms (TAA) and dissections are not uncommon causes of sudden death in young adults. Loeys-Dietz syndrome (LDS) is a rare, recently described, autosomal dominant, connective tissue disease characterized by aggressive arterial aneurysms, resulting from mutations in the transforming growth factor beta (TGFβ) receptor genes TGFBR1 and TGFBR2. Mean age at death is 26.1 years, most often due to aortic dissection. We report an unusually late presentation of LDS, diagnosed following elective surgery in a female with a long history of joint hypermobility. Methods: A 51-year-old Caucasian lady complained of chest pain and headache following a dural leak from spinal anaesthesia for an elective ankle arthroscopy. CT scan and echocardiography demonstrated a dilated aortic root and significant aortic regurgitation. MRA demonstrated aortic tortuosity, an infrarenal aortic aneurysm and aneurysms in the left renal and right internal mammary arteries. She underwent aortic root repair and aortic valve replacement. She had a background of long-standing joint pains secondary to hypermobility, easy bruising, unusual fracture susceptibility and mild bronchiectasis. She had one healthy child age 32, after which she suffered a uterine prolapse. Examination revealed mild Marfanoid features. Uvula, skin and ophthalmological examination was normal. Results: Fibrillin-1 testing for Marfan syndrome (MFS) was negative. Detection of a c.1270G > C (p.Gly424Arg) TGFBR2 mutation confirmed the diagnosis of LDS. Losartan was started for vascular protection. Conclusions: LDS is a severe inherited vasculopathy that usually presents in childhood. It is characterized by aortic root dilatation and ascending aneurysms. There is a higher risk of aortic dissection compared with MFS. Clinical features overlap with MFS and Ehlers Danlos syndrome Type IV, but differentiating dysmorphogenic features include ocular hypertelorism, bifid uvula and cleft palate. Echocardiography and MRA or CT scanning from head to pelvis is recommended to establish the extent of vascular involvement. Management involves early surgical intervention, including early valve-sparing aortic root replacement, genetic counselling and close monitoring in pregnancy. Despite being caused by loss of function mutations in either TGFβ receptor, paradoxical activation of TGFβ signalling is seen, suggesting that TGFβ antagonism may confer disease modifying effects similar to those observed in MFS. TGFβ antagonism can be achieved with angiotensin antagonists, such as Losartan, which is able to delay aortic aneurysm development in preclinical models and in patients with MFS. Our case emphasizes the importance of timely recognition of vasculopathy syndromes in patients with hypermobility and the need for early surgical intervention. It also highlights their heterogeneity and the potential for late presentation. Disclosures: The authors have declared no conflicts of interes

    Understanding gamification experiences with the benefits dependency network lens

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    While many gamification studies have shown measurable positive benefits for learner emotions and outcomes, mixed results continue to be reported. In this study, we focus on understanding a less than fully successful gamification experience. We examine how gamification during training and learning can be improved by expanding our view of the implementation context. This entails seeing gamification as an ensemble of technologies and humans that uses a cyclical process involving technology selection, gamification enablement, and the resulting combinations of affordances and actions by both educators/trainers and learners. In this paper, we first describe this gamification attempt and then propose that the Benefits Dependency Network (BDN), a concept from the information systems perspective, may be used as a lens to understand gamification experiences and increase the likelihood of future success. This lens engenders deep reflection not only about how the gamification process works, but about all the enabling conditions that need to be present in order to maintain, enhance, or disrupt the status quo in a given education or training setting. We assert that analysis using the BDN may reveal why some gamification studies have been inconclusive and provide insights for both researchers and implementers to achieve stronger results from gamification in the education/training context

    Heterocycles from ketenimines. 12. Pyrrolo[3,2-b]pyridines

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    Weed control improves survival of transplanted blue oak

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    Weed competition is recognized as a factor affecting survival of California blue oak seedlings in artificial plantings. Three alternative weed-control strategies were examined in a series of annual plantings at two locations using 2- to 3-month-old nursery stock. The effects of herbicides, porous plastic mulch mats and impervious plastic mats were compared. No one strategy was superior, but all resulted in greater seedling survival than with no weed control, and generally also resulted in taller blue oaks. Use of herbicides was the least-expensive weed-control method. Much of the seedling mortality was attributed to depredation by rodents
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