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101.
A collaborative virtual sculpting system supports a team of geographically separated designers/engineers connected by networks to participate in designing three-dimensional (3D) virtual engineering tools or sculptures. It encourages international collaboration at a minimal cost. However, in order for the system to be useful, two factors need to be addressed: intuitiveness and real-time interaction. Although a lot of effort has been put into developing virtual sculpting environments, only limited work addresses collaborative virtual sculpting. This is because in order to support real-time collaborative virtual sculpting, many challenging issues need to be addressed. We propose a collaborative virtual sculpting framework, called VSculpt. Through adapting some techniques we developed earlier and integrating them with some techniques developed here, the proposed framework provides a real-time intuitive environment for collaborative design. In particular, it addresses issues on efficient rendering and transmission of deformable objects, intuitive object deformation using the CyberGlove and concurrent object deformation by multiple clients. We demonstrate and evaluate the performance of the proposed framework through a number of experiments. 相似文献
102.
Balster Robert L.; de Wit Harriet; Dykstra Linda A.; Ensminger Margaret E. 《Canadian Metallurgical Quarterly》2011,66(7):633
Charles R. (Bob) Schuster, an internationally recognized researcher on the psychopharmacology of drugs of abuse, passed away on February 21, 2011. Bob Schuster was a pioneer in the scientific study of addiction and one of the founders of a specialized research field called behavioral pharmacology. Bob mentored many young scientists, including 15 doctoral students, 9 postdoctoral fellows, and many visiting scientists from around the world, as well as junior faculty members at the academic institutions where he had faculty appointments. Bob was active in numerous professional organizations and was the recipient of many national and international awards. Personally, Bob Schuster touched the lives of a great many people: his students, colleagues, extended family, and many friends. Bob is survived by his wife and colleague Chris-Ellyn Johanson; four children, Lyzbett, Rebecca, Robert, and Alyson; and seven grandchildren. He is also survived by his sister Bette Quemore. He was a man of many talents, a loving husband and father, and a great friend. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Izadora de Souza Maria Carolina Clares Ramalho Camila Banca Guedes Isabeli Yumi Araújo Osawa Linda Karolynne Seregni Monteiro Luciana Rodrigues Gomes Clarissa Ribeiro Reily Rocha 《International journal of molecular sciences》2022,23(13)
Glioblastoma multiforme is a lethal disease and represents the most common and severe type of glioma. Drug resistance and the evasion of cell death are the main characteristics of its malignancy, leading to a high percentage of disease recurrence and the patients’ low survival rate. Exploiting the modulation of cell death mechanisms could be an important strategy to prevent tumor development and reverse the high mortality and morbidity rates in glioblastoma patients. Ferroptosis is a recently described type of cell death, which is characterized by iron accumulation, high levels of polyunsaturated fatty acid (PUFA)-containing phospholipids, and deficiency in lipid peroxidation repair. Several studies have demonstrated that ferroptosis has a potential role in cancer treatment and could be a promising approach for glioblastoma patients. Thus, here, we present an overview of the mechanisms of the iron-dependent cell death and summarize the current findings of ferroptosis modulation on glioblastoma including its non-canonical pathway. Moreover, we focused on new ferroptosis-inducing compounds for glioma treatment, and we highlight the key ferroptosis-related genes to glioma prognosis, which could be further explored. Thereby, understanding how to trigger ferroptosis in glioblastoma may provide promising pharmacological targets and indicate new therapeutic approaches to increase the survival of glioblastoma patients. 相似文献
105.
Rönner AC Engvall EO Andersson L Kaijser B 《International journal of food microbiology》2004,96(2):173-179
Campylobacter is today the most common cause of human bacterial enteritis in Sweden, as well as in most other industrialized countries. Common sources of infection are undercooked chicken meat, unpasteurized milk and contaminated drinking water. One aim with our present study was to identify the species Campylobacter jejuni and Campylobacter coli strains from humans and chickens using a polymerase chain reaction/restriction enzyme analysis (PCR/REA) method, as well as traditional hippurate hydrolysis test. Another aim was to investigate the antibiotic resistance pattern of the human domestic C. jejuni/C. coli isolates from infected patients and isolates from healthy Swedish chicken, as well as isolates from humans infected abroad. If discrimination between C. jejuni and C. coli was based on testing for hippurate hydrolysis, 95% of the human domestic strains and 88% of the chicken strains were identified as C. jejuni. Based on genotyping by PCR/REA, 100% of the human domestic strains and 98% of the chicken strains were attributed to C. jejuni. The E-test and disc diffusion methods were used for phenotypic antibiotic resistance studies. The two methods gave similar results. Most Swedish C. jejuni/C. coli isolates both from humans and chickens were sensitive to doxycycline and erythromycin, which are antibiotics used to treat human infection. Only 7% of the human domestic strains and 2% of the chicken strains were resistant to the quinolones tested. As a comparison, more than 94% of strains isolated from travelers to Asia and southern Europe showed antibiotic resistance to one or more drugs. 相似文献
106.
Wang Z Lau BP Tague B Sparling M Forsyth D 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2011,28(6):799-806
A sensitive and selective isotope dilution ion chromatography/tandem mass spectrometry (ID IC-MS/MS) method was developed and validated for the determination of perchlorate in infant formula. The perchlorate was extracted from infant formula by using 20 ml of methanol and 5 ml of 1% acetic acid. All samples were spiked with (18)O(4) isotope-labelled perchlorate internal standard prior to extraction. After purification on a graphitised carbon solid-phase extraction column, the extracts were injected into an ion chromatography system equipped with an Ionpac AS20 column for separation of perchlorate from other anions. The presence of perchlorate in samples was quantified by isotope dilution mass spectrometry. Analysis of both perchlorate and its isotope-labelled internal standard was carried out on a Waters Quattro Ultima triple quadrupole mass spectrometer operating in a multiple reaction monitoring (MRM) negative ionisation mode. The method was validated for linearity and range, accuracy, precision, sensitivity, and matrix effects. The limit of quantification (LOQ) was 0.4 μg l(-1) for liquid infant formula and 0.95 μg kg(-1) for powdered infant formula. The recovery ranged from 94% to 110% with an average of 98%. This method was used to analyse 39 infant formula, and perchlorate concentrations ranging from 相似文献
107.
Francis C. Lau James A. Joseph Jane E. McDonald Wilhelmina Kalt 《Journal of Functional Foods》2009,1(3):274-283
Treatment of BV2 microglial cells with blueberry extracts has been shown to be effective in reducing lipopolysaccharide (LPS)-induced proinflammatory mediators such as nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), inducible NO synthase (iNOS), and cyclooxygenase 2 (COX2). The current study explored the possibility that the down-regulation of iNOS and COX2 by blueberry extracts was mediated through NF-κB signaling pathway. A column-purified fraction of polyphenol-enriched blueberry extract (PC18) was used to treat LPS-activated BV2 cells. The results thus far showed that blueberry polyphenols significantly suppressed iNOS and COX2 promoter activities. In addition, blueberry polyphenols inhibited NF-κB nuclear translocation in LPS-activated BV2 cells. These findings suggested that the beneficial effects of blueberries may involve direct modulation of oxidative stress and/or inflammatory signaling cascades. 相似文献
108.
Berger Seymour M.; Hampton Katherine L.; Carli Linda L.; Grandmaison Paul S.; Sadow Janice S.; Donath Clifford H.; Herschlag Laura R. 《Canadian Metallurgical Quarterly》1981,40(3):479
Three experiments with 204 undergraduates examined the hypothesis that an audience can inhibit overt practice and thereby impair learning of unfamiliar words and enhance learning of familiar words. This hypothesis was derived from an analysis of motoric and symbolic mediation during learning. In comparison with learning while alone, the results show that the audience inhibited overt practice of unfamiliar and familiar words and that reduced practice was detrimental to learning unfamiliar words. Inhibition of overt practice with an audience enhanced learning of familiar words in only 1 of the experiments. Instructions to practice overtly reduced the audience-inhibition effect in learning unfamiliar words. The studies are discussed in the context of drive-theory explanations for social facilitation effects in learning. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
110.
Zhao Yan Yu Han Liying Lin Ying Xue Chao Ma Wai Kit Ng Kam Sing Wong Kei May Lau 《光:科学与应用(英文版)》2021,(11):2143-2152
The deployment of photonic integrated circuits (PICs) necessitates an integration platform that is scalable, high-throughput, cost-effective, and power-efficien... 相似文献