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991.
Patricia Navarro‐Javierre Manuel‐Alfredo Garcia‐Romeu‐Martinez Vicente‐Agustin Cloquell‐Ballester Enrique de‐la‐Cruz‐Navarro 《Packaging Technology and Science》2012,25(4):217-231
Because of the negative environmental impact of using traditional polymeric materials for cushioning in protective packaging, the interest in optimization of cushion design resulting in replacement or reduction of the amount of cushioning materials has increased in recent years. It has been generally accepted that the shock absorbing characteristics for cushioning materials are presented as the so‐called cushion curves, i.e. graphs of peak acceleration of shocks versus the corresponding static stress, presented over a range of static stress conditions for a specific material thickness and at a specific drop height. The cushion curves are mainly used to design and optimize cushion packaging. This information is specific to each packaging manufacturer, particular chemical formulation and manufacturing process. The traditional method to obtain cushion curves of a specific material is described in ASTM D1596, but this method requires enormous amounts of test data, is time consuming and expensive. For this reason, cushion curves provided by manufacturers are rarely updated and often are obsolete. In recent years, alternative methods have been developed to obtain cushion curves in a significantly shorter time required for testing. To achieve a wide use of these methods, it is necessary to know their accuracy in comparison with the ASTM D1596 method. The objective of this paper is to compare two of those alternative methods with the standard ASTM D1596 method, by applying them to obtain the cushion curves of two typical cushioning materials. More specifically, the single compression data method developed by Sek et al. and the stress–energy method (dynamic stress versus dynamic energy) developed by Burgess were applied to obtain cushion curves for expanded polystyrene with density 15 kg/m3 and for polyethylene Ethafoam® (Modisprem S.A. Zaragoza, Spain) with density 29 kg/m3 and are presented in this paper. The effectiveness of these alternative methods for developing cushion curves and their advantages, disadvantages and limitations are discussed. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
992.
Sevil Korkmaz-Icz Cenk Kocer Alex A. Sayour Patricia Kraft Mona I. Benker Sophia Abulizi Adrian-Iustin Georgevici Paige Brlecic Tams Radovits Sivakkanan Loganathan Matthias Karck Gbor Szab 《International journal of molecular sciences》2021,22(15)
Vascular ischemia/reperfusion injury (IRI) contributes to graft failure and adverse clinical outcomes following coronary artery bypass grafting. Sodium-glucose-cotransporter (SGLT)-2-inhibitors have been shown to protect against myocardial IRI, irrespective of diabetes. We hypothesized that adding canagliflozin (CANA) (an SGLT-2-inhibitor) to saline protects vascular grafts from IRI. Aortic rings from non-diabetic rats were isolated and immediately mounted in organ bath chambers (control, n = 9–10 rats) or underwent cold ischemic preservation in saline, supplemented either with a DMSO vehicle (IR, n = 8–10 rats) or 50µM CANA (IR + CANA, n = 9–11 rats). Vascular function was measured, the expression of 88 genes using PCR-array was analyzed, and feature selection using machine learning was applied. Impaired maximal vasorelaxation to acetylcholine in the IR-group compared to controls was significantly ameliorated by CANA (IR 31.7 ± 3.2% vs. IR + CANA 51.9 ± 2.5%, p < 0.05). IR altered the expression of 17 genes. Ccl2, Ccl3, Ccl4, CxCr4, Fos, Icam1, Il10, Il1a and Il1b have been found to have the highest interaction. Compared to controls, IR significantly upregulated the mRNA expressions of Il1a and Il6, which were reduced by 1.5- and 1.75-fold with CANA, respectively. CANA significantly prevented the upregulation of Cd40, downregulated NoxO1 gene expression, decreased ICAM-1 and nitrotyrosine, and increased PECAM-1 immunoreactivity. CANA alleviates endothelial dysfunction following IRI. 相似文献
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994.
McCaul Kevin D.; Schroeder Dawn M.; Reid Patricia A. 《Canadian Metallurgical Quarterly》1996,15(6):430
Breast cancer concerns were measured among 353 women, ages 40–75, from North Dakota. One year later, participants were recontacted and asked about their screening behavior during the previous year. Greater concern about breast cancer, even the highest level of concern, was related to a higher likelihood that women performed breast self-examination, had a mammography screening, and had a clinical breast examination. These data do not support the idea that worry inhibits action; instead, they suggest that nonpathological worry motivates self-protective behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Reid Larry D.; Hubbell Christopher L.; Glick Stanley D.; Boswell Karen J.; Chen Alice M.; Moran Catherine M.; Cramer Christopher M.; Mullen Ursula D.; Chambers Michael D.; Gonzales Patricia M.; Irizarry Kristopher L.; Amendola Christopher A. 《Canadian Metallurgical Quarterly》1996,4(3):271
The authors explored naltriben's (NTB, a delta opioid antagonist) potential to be a pharmacotherapy for cocaine abuse. NTB (3–6 mg/kg) reduced rats' (Rattus norvegicus) intravenous, self-administration of cocaine, daily, across 5 days. NTB did not, however, interfere with rats' pressing for water. NTB (3 mg/kg) blocked cocaine's facilitation of pressing for brain stimulation, daily, for 5 days. As doses of NTB were explored, it was found that 10 mg/kg of NTB was lethal for about one third of the rats. Smaller doses (e.g., 3 mg/kg) gave some indications of toxicity as indexed by NTB's tendency to reduce pressing for brain stimulation by itself. NTB (3 mg/kg) induced a mild conditioned taste aversion but had no negative effects on rats' ability to learn and remember a sequence of mazes. Taken together, these results lead to the suggestion that opioidergic processes play an important role in mediating cocaine's reinforcement. Although NTB may not be the ideal opioid antagonist for treating people, it has many positive properties supporting further investigation of opioid antagonists as agents for treating cocaine addiction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
997.
998.
Patricia Hasslinger Viktoria Vass Alexander Dejaco Romane Blanchard Gissur Örlygsson Paolo Gargiulo 《International Journal for Computational Methods in Engineering Science and Mechanics》2016,17(3):222-244
Due to its high resolution, micro-CT (Computed Tomograph) scanning is the key to assess bone quality of sham and OVX (ovariectomized) rats. Combination of basic X-ray physics, such as the energy- and chemistry-dependence of attenuation coefficients, with results from ashing tests on rat bones, delivers mineral, organic, and water volume fractions within the voxels. Additional use of a microelastic model for bone provides voxel-specific elastic properties. The new method delivers realistic bone mass densities, and reveals that OVX protocols may indeed induce some bone mass loss, while the average composition of the bone tissue remains largely unaltered. 相似文献
999.
Huffman algorithm allows for constructing optimal prefix‐codes with O(n·logn) complexity. As the number of symbols ngrows, so does the complexity of building the code‐words. In this paper, a new algorithm and implementation are proposed that achieve nearly optimal coding without sorting the probabilities or building a tree of codes. The complexity is proportional to the maximum code length, making the algorithm especially attractive for large alphabets. The focus is put on achieving almost optimal coding with a fast implementation, suitable for real‐time compression of large volumes of data. A practical case example about checkpoint files compression is presented, providing encouraging results. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
1000.
Tiffany Jastrzembski Neil Charness Patricia Holley Jeffrey Feddon 《Universal Access in the Information Society》2005,4(1):39-45
The work reported in this paper examined performance on a mixed pointing and data entry task using direct and indirect positioning devices for younger, middle-aged, and older adults (n=72) who were experienced mouse users. Participants used both preferred and non-preferred hands to perform an item selection and text entry task simulating a typical web page interaction. Older adults performed more slowly than middle-aged adults who in turn performed more slowly than young adults. Performance efficiency was superior with the mouse for older adults only on the first two trial blocks. Thereafter mouse and light pen yielded equivalent performance. For other age groups, mouse and light pen were equivalent at all points of practice. Contrary to prior research revealing superior performance with a light pen for pure pointing tasks, these results suggest that older adults may initially perform worse with a light pen than a mouse for mixed tasks. 相似文献