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51.
Kate Sanders Sally Fincher Dennis Bouvier Gary Lewandowski Briana Morrison Laurie Murphy Marian Petre Brad Richards Josh Tenenberg Lynda Thomas Richard Anderson Ruth Anderson Sue Fitzgerald Alicia Gutschow Susan Haller Raymond Lister Renée McCauley John McTaggart Christine Prasad Terry Scott Dermot Shinners-Kennedy Suzanne Westbrook Carol Zander 《Expert Systems》2005,22(3):121-128
Abstract: This paper presents a case study of the use of a repeated single‐criterion card sort with an unusually large, diverse participant group. The study, whose goal was to elicit novice programmers' knowledge of programming concepts, involved over 20 researchers from four continents and 276 participants drawn from 20 different institutions. In this paper we present the design of the study and the unexpected result that there were few discernible systematic differences in the population. The study was one of the activities of the National Science Foundation funded Bootstrapping Research in Computer Science Education project (2003). 相似文献
52.
Boris Kapilevich Yosef Pinhasi Ruth Arusi Michael Anisimov Danny Hardon Boris Litvak Yan Wool 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(11):1370-1381
A single-pixel imaging remote sensor operating at 330 GHz is described. It is based on a frequency modulated continuous wave
(FMCW) and aimed at detection of concealed objects for ranges up to 40 m. The system consists of 2 horn-lens antennas integrated
with a homodyne transceiver. The synthesized linear FMCW signal at X-band is multiplied by a factor of 32 to generate the
transmitted signal. An intermediate frequency (IF) signal obtained in the output port of the 2-nd harmonic mixer is employed
for image processing. Distance measurements were made by performing data acquisition unit based on LabView interface and resulting
in a range resolution about 1 cm. Examples of 2D and 3D images reconstructed with this sensor are presented. 相似文献
53.
Ruth T. Massey 《Journal of Housing and the Built Environment》2013,28(4):605-613
The South African National Department of Housing’s ‘Breaking New Ground: A Comprehensive Plan for the Creation of Sustainable Human Settlements’ was released in 2004. This policy directive acknowledged that informal settlements had grown significantly since 1994. It resulted in the development and implementation of the informal settlement upgrading programme across the country. The principle objective of the study discussed in this paper was to investigate the City of Cape Town’s (the City) rationale in the technique of upgrading the informal settlements of Makhaza and New Rest in Cape Town and explore the implications of this rationale for women’s social networks in these two settlements. The research has found that the rationale used by the City to plan and implement the upgrading of informal settlements is contradictory to the needs of the residents within these settlements. The settlements therefore do not meet the needs of the residents (particularly women) and do not enable or ensure the maintenance of strong social relationships which are crucial for the survival of livelihoods in these areas. 相似文献
54.
Using functional programming to recognize named structure in an optimization problem: Application to pooling 下载免费PDF全文
Francesco Ceccon Georgia Kouyialis Ruth Misener 《American Institute of Chemical Engineers》2016,62(9):3085-3095
Branch‐and‐cut optimization solvers typically apply generic algorithms, e.g., cutting planes or primal heuristics, to expedite performance for many mathematical optimization problems. But solver software receives an input optimization problem as vectors of equations and constraints containing no structural information. This article proposes automatically detecting named special structure using the pattern matching features of functional programming. Specifically, we deduce the industrially‐relevant nonconvex nonlinear Pooling Problem within a mixed‐integer nonlinear optimization problem and show that we can uncover pooling structure in optimization problems which are not pooling problems. Previous work has shown that preprocessing heuristics can find network structures; we show that we can additionally detect nonlinear pooling patterns. Finding named structures allows us to apply, to generic optimization problems, cutting planes or primal heuristics developed for the named structure. To demonstrate the recognition algorithm, we use the recognized structure to apply primal heuristics to a test set of standard pooling problems. © 2016 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers AIChE J, 62: 3085–3095, 2016 相似文献
55.
Enhancing the electrical conductivity of carbon black/graphite nanoplatelets: Poly(ethylene‐butyl acrylate) composites by melt extrusion 下载免费PDF全文
The influence of processing parameters such as screw geometry, temperature profile, and screw speed on the electrical properties of hybrid composites consisting of graphite nanoplatelets and carbon black in ethyl butyl acrylate was studied. Two different screws were used to compound the hybrid composites at two different temperatures and two different screw speeds. A beneficial effect was noted with regard to the electrical properties when adding nanoplatelets to the filler system. The cause could be a synergistic effect due to the difference in particle shape of the two fillers. Lower percolation thresholds were obtained with the conventional screw due to less breakage of the graphite nanoplatelets compared to the barrier screw. No significant changes of the electrical properties were observed when changing the temperature profiles or the screw speeds. Furthermore, the melt viscosity of the compounds was not appreciably affected at the rather low filler contents used here. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42897. 相似文献
56.
Prof. Dr. Ruth Birner‐Gruenberger Prof. Dr. Rolf Breinbauer 《Chembiochem : a European journal of chemical biology》2016,17(16):1488-1490
Recently, Hang and co‐workers developed “acyl‐PEG exchange” (APE), which allows the investigation of protein S‐fatty acylation with mass‐tag labelling and gel electrophoresis, methods that are accessible to any biochemistry laboratory. 相似文献
57.
Avanish Bharati Prakhyat Hejmady Tom Van der Donck Jin Won Seo Ruth Cardinaels Paula Moldenaers 《应用聚合物科学杂志》2020,137(9):48433
An approach to induce conductivity in immiscible polystyrene/polypropylene (PS/PP) blends is described using a percolated conducting polyaniline/polyamide (PANI/PA) filler combined with a polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene-graft-maleic anhydride compatibilizer. The approach is based on the ability of the compatibilizer to concomitantly stabilize the cocontinuous morphology and to improve the state of dispersion of the PANI/PA filler. Selective localization of PANI/PA in the PS phase with improved filler dispersion is achieved with the optimal master batch (MB) preparation technique followed by its optimized sequence addition to the blend components. This results in an increase in the dc conductivity by six decades as compared with that of the neat compatibilized blend at an effective 4.8-wt % PANI concentration. An investigation of the effect of functionality and concentration of the filler and the compatibilizer on the filler connectivity in the blend is performed. The prevailing specific interactions are analyzed by Fourier transform infrared spectroscopy and thermogravimetric analysis of the MBs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48433. 相似文献
58.
Luis M. Montao Bettina Sommer Juan C. Gomez-Verjan Genaro S. Morales-Paoli Gema Lizbeth Ramírez-Salinas Hctor Solís-Chagoyn Zuly A. Sanchez-Florentino Eduardo Calixto Gloria E. Prez-Figueroa Rohan Carter Ruth Jaimez-Melgoza Bianca S. Romero-Martínez Edgar Flores-Soto 《International journal of molecular sciences》2022,23(8)
Theophylline (3-methyxanthine) is a historically prominent drug used to treat respiratory diseases, alone or in combination with other drugs. The rapid onset of the COVID-19 pandemic urged the development of effective pharmacological treatments to directly attack the development of new variants of the SARS-CoV-2 virus and possess a therapeutical battery of compounds that could improve the current management of the disease worldwide. In this context, theophylline, through bronchodilatory, immunomodulatory, and potentially antiviral mechanisms, is an interesting proposal as an adjuvant in the treatment of COVID-19 patients. Nevertheless, it is essential to understand how this compound could behave against such a disease, not only at a pharmacodynamic but also at a pharmacokinetic level. In this sense, the quickest approach in drug discovery is through different computational methods, either from network pharmacology or from quantitative systems pharmacology approaches. In the present review, we explore the possibility of using theophylline in the treatment of COVID-19 patients since it seems to be a relevant candidate by aiming at several immunological targets involved in the pathophysiology of the disease. Theophylline down-regulates the inflammatory processes activated by SARS-CoV-2 through various mechanisms, and herein, they are discussed by reviewing computational simulation studies and their different applications and effects. 相似文献
59.
Raquel Martín-Venegas M.Teresa Brufau Ana Maria Guerrero-Zamora Yves Mercier Pierre-André Geraert Ruth Ferrer 《Food chemistry》2013
dl-2-hydroxy-(4-methylthio)butanoic acid (HMTBA) is a source of dietary methionine (Met) that is widely used in poultry nutrition. We have previously shown that HMTBA is preferentially diverted to the transsulfuration pathway, which gives antioxidant metabolites such as taurine and glutathione. Therefore, here we hypothesize that this Met source can protect epithelial barrier function in an in vitro model of intestinal inflammation of Caco-2 cells. The results show that HMTBA prevents the increase in paracellular permeability induced by H2O2 or tumour necrosis factor-α. This effect can be attributed to the increased production of taurine and reduced glutathione. Similar results were obtained for dl-Met, although the protective role of the amino acid was less pronounced than that of the hydroxy analogue. In conclusion, the diversion to the transsulfuration pathway means that this Met precursor is of greater value than previously thought, due to its capacity to improve intestinal homeostasis and the quality of poultry products destined for human consumption. 相似文献
60.
Nutritional properties of medium-chain triglycerides 总被引:1,自引:0,他引:1
The biological effects of MCT (medium-chain triglycerides) differed from those of conventional fats, and certain of these
suggested examination of the fatty acid composition and triglyceride structure of the adipose tissues and other organs of
rats which were fed medium- or long-chain triglyceride mixtures with two levels of linoleic acid. Fatty acid compositions
and TG patterns varied with the tissue, with the dietary fat, and with the level of linoleate in the diet. Increasing the
latter resulted in the deposition of more linoleate at the expense of oleate and in the deposition of more of the dietary
fatty acids. The percentage of completely saturated triglyc-erides (S3), in adipose tissue with the higher linoleate supplement in the rats fed MCT, decreased in those fed LCT and was unchanged
in the controls fed a fat-free diet. The increased deposition of the dietary fatty acids was more pronounced in the S3 band.
Supported by Grants U-1347 and U-1510 from the Health Research Council of the City of New York. 相似文献