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221.
Perceived organizational support. 总被引:6,自引:0,他引:6
Eisenberger Robert; Huntington Robin; Hutchison Steven; Sowa Debora 《Canadian Metallurgical Quarterly》1986,71(3):500
Administered a survey of perceived organizational support (SPOS) to 361 employees (among them postal clerks, financial trust company employees, and manufacturing firm workers) and 71 private high school teachers in 2 studies. Teachers also completed an exchange-ideology questionnaire that measured their belief that work effort should depend on treatment by the organization. Results show that (a) employees in an organization form global beliefs concerning the extent to which the organization values their contributions and cares about their well-being, (b) such perceived organizational support reduces absenteeism, and (c) the relation between perceived organizational support and absenteeism is greater for employees with a strong exchange ideology than those with a weak ideology. These findings support the social exchange view that employees' commitment to the organization is strongly influenced by their perception of the organization's commitment to them. Perceived organizational support is assumed to increase the employee's affective attachment to the organization and his/her expectancy that greater effort toward meeting organizational goals will be rewarded. It is concluded that the extent to which these factors increase work effort depends on the strength of the employee's exchange ideology favoring the trade of work effort for material and symbolic benefits. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
222.
Salthouse Timothy A.; Mitchell Debora R.; Skovronek Eric; Babcock Renee L. 《Canadian Metallurgical Quarterly》1989,15(3):507
Three predictions were derived from the hypothesis that adult age differences in certain measures of cognitive functioning are attributable to age-related reductions in a processing resource such as working-memory capacity. Each prediction received at least some degree of empirical support in a study involving 120 males ranging between 20 and 79 years of age. First, older adults exhibited greater impairments of performance than did young adults when task complexity increased and more demands were placed on the limited processing resources: second, the magnitudes of these complexity effects were highly correlated across verbal (reasoning) and spatial (paper folding) tasks. Finally, statistical control of an index of a working-memory processing resource attenuated the effects of age on the measures of cognitive performance. It was concluded that further progress in understanding the mechanisms of the relation between age and cognitive functioning will require improved conceptualizations of the nature of working memory or other hypothesized mediating constructs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
223.
Hoare T Timko BP Santamaria J Goya GF Irusta S Lau S Stefanescu CF Lin D Langer R Kohane DS 《Nano letters》2011,11(3):1395-1400
Drug delivery devices based on nanocomposite membranes containing thermoresponsive nanogels and superparamagnetic nanoparticles have been demonstrated to provide reversible, on-off drug release upon application (and removal) of an oscillating magnetic field. We show that the dose of drug delivered across the membrane can be tuned by engineering the phase transition temperature of the nanogel, the loading density of nanogels in the membrane, and the membrane thickness, allowing for on-state delivery of model drugs over at least 2 orders of magnitude (0.1-10 μg/h). The zero-order kinetics of drug release across the membranes permit drug doses from a specific device to be tuned according to the duration of the magnetic field. Drugs over a broad range of molecular weights (500-40000 Da) can be delivered by the same membrane device. Membrane-to-membrane and cycle-to-cycle reproducibility is demonstrated, suggesting the general utility of these membranes for drug delivery. 相似文献
224.
Silvana Alfei Debora Caviglia Gabriella Piatti Guendalina Zuccari Anna Maria Schito 《International journal of molecular sciences》2021,22(14)
The genus Acinetobacter consists of Gram-negative obligate aerobic pathogens, including clinically relevant species, such as A. baumannii, which frequently cause hospital infections, affecting debilitated patients. The growing resistance to antimicrobial therapies shown by A. baumannii is reaching unacceptable levels in clinical practice, and there is growing concern that the serious conditions it causes may soon become incurable. New therapeutic possibilities are, therefore, urgently needed to circumvent this important problem. Synthetic cationic macromolecules, such as cationic antimicrobial peptides (AMPs), which act as membrane disrupters, could find application in these conditions. A lysine-modified cationic polyester-based dendrimer (G5-PDK), capable of electrostatically interacting with bacterial surfaces as AMPs do, has been synthesized and characterized here. Given its chemical structure, similar to that of a fifth-generation lysine containing dendrimer (G5K) with a different core, and previously found inactive against Gram-positive bacterial species and Enterobacteriaceae, the new G5-PDK was also ineffective on the species mentioned above. In contrast, it showed minimum inhibitory concentration values (MICs) lower than reported for several AMPs and other synthetic cationic compounds on Acinetobacter genus (3.2–12.7 µM). Time-kill experiments on A. baumannii, A. pittii, and A. ursingii ascertained the rapid bactericidal effects of G5-PDK, while subsequent bacterial regrowth supported its self-biodegradability. 相似文献
225.
Hellen Regina Oliveira de Almeida Beatriz Ferreira de Carvalho Patricio Yasmin do Anjos Garcia Talita Goulart da Silva Debora Baptista Pereira Michelle Alvares Sarcinelli Helvécio Vinícius Antunes Rocha Roberta Helena Mendonça 《应用聚合物科学杂志》2021,138(37):50944
Olanzapine (OLZ) is a commonly antipsychotic used to treat schizophrenia, a mental illness, with fewer side effects when compared with other drugs of the same class. It is commercialized mainly as oral tablets and orally disintegrating tablets. However, this drug oral bioavailability is affected by the first pass effect and low solubility in water. This requires high daily doses that can cause more side effects and poor treatment compliance. Also, the frequency of frequency of tablet intake is commonly related to patients' abandonment of schizophrenia treatment. So, the development of implantable biomaterials for OLZ delivery can be an alternative to solve both problems, since this material can, potentially, be used subcutaneously in less frequent administrations, thus the treatment has a greater chance of success. Therefore, the objective of this work was to produce polycaprolactone (PCL) rods incorporated with OLZ by hot-melt extrusion technique. The rods were characterized by different techniques, which showed an amount of 6.78 ± 0.56 mg of OLZ per rod. The in vitro release studies were performed and they showed a controlled release of the drug that followed the Higuchi's model. These results indicated that the PCL/OLZ rods have potential application in the schizophrenia treatment. 相似文献
226.
Tavana Madjid Khalili-Damghani Kaveh Di Caprio Debora Oveisi Zeynab 《Neural computing & applications》2018,30(1):127-139
Neural Computing and Applications - The redundancy allocation problem (RAP) is an optimization problem for maximizing system reliability at a predetermined time. Among the several extensions of... 相似文献
227.
Michele Mesomo Marceli Fernandes Silva Gabriela Boni Francine Ferreira Padilha Marcio Mazutti Altemir Mossi Debora de Oliveira Rogério Luis Cansian Marco Di Luccio Helen Treichel 《Journal of the science of food and agriculture》2009,89(14):2440-2445
BACKGROUND: This aim of this study was the production and rheological characterisation of xanthan gum by Xanthomonas campestris pv. mangiferaeindicae IBSBF 1230 using industrial media and experimental design techniques in a bench bioreactor. RESULTS: The optimised conditions for the production of xanthan starting with 900 mL of cheese whey were 1 g L?1 magnesium sulphate, 20 g L?1 potassium phosphate, 28 °C temperature and initial pH 7.2 at 390 rpm agitation and 1.5 vvm aeration, resulting in 36 g L?1 gum in 72 h. The highest viscosity obtained in the production optimisation study was 1831.34 mPa s at 25 °C with 30 g L?1 gum. The use of CaCl2 resulted in the highest solution viscosity under conditions of 25 °C, 1 g L?1 salt and 46.8 g L?1 gum, with a value of 1704.53 mPa s. CONCLUSION: In this study, cheese whey, a by‐product of the dairy industry, was used as substrate in the production of xanthan gum, a valuable product in food applications, with optimised high gum production in a bioreactor and a wide range of viscosity values. Copyright © 2009 Society of Chemical Industry 相似文献
228.
Francesco Caponio Carmine Summo Debora Delcuratolo Antonella Pasqualone 《Journal of the science of food and agriculture》2006,86(3):356-361
Although not perceived as fatty foods by consumers, biscuits contain a consistent quantity of lipids. Since they are daily present in the diet, an experimental study was carried out with the aim of evaluating the quality of the lipid fraction of biscuits. Amounts of fat ranging from 75 to 231 g kg?1, mainly constituted by refined vegetable oils and margarine, were present. A high variability in fatty acid composition was found and in some cases high amounts of trans isomers of unsaturated fatty acid were observed. In addition, HPSEC analysis of polar compounds indicated an extensive hydrolytic degradation of triacylglycerols and also a high level of oxidative degradation. The latter, demonstrated by means of the contemporary measure of oxidised triacylglycerols and of triacylglycerol oligopolymers, was comparable to that found in hydrogenated oils and fats. Copyright © 2005 Society of Chemical Industry 相似文献
229.
Mariarosa Cavallo Erwan Bossavit Sylvia Matzen Thomas Maroutian Rodolphe Alchaar Tung Huu Dang Adrien Khalili Corentin Dabard Huichen Zhang Yoann Prado Claire Abadie James K Utterback Jean Francois Dayen Mathieu G. Silly Pavel Dudin Jose Avila Emmanuel Lhuillier Debora Pierucci 《Advanced functional materials》2023,33(34):2300846
The design of infrared nanocrystals-based (NCs) photodiodes faces a major challenge related to the identification of barriers with a well-suited band alignment or strategy to finely control the carrier density. Here, this study explores a general complementary approach where the carrier density control is achieved by coupling an NC layer to a ferroelectric material. The up-and-down change in ferroelectric polarization directly impacts the NC electronic structure, resulting in the formation of a lateral pn junction. This effect is uncovered directly using nano X-ray photoemission spectroscopy, which shows a relative energy shift of 115 meV of the NC photoemission signal over the two different up- and down-polarized ferroelectric regions, a shift as large as the open circuit value obtained in the diode stack. The performance of this pn junction reveals enhanced responsivity and reduced noise that lead to a factor 40 increase in the detectivity value. 相似文献
230.
Alexander R. Uhl Peter Fuchs Alexandra Rieger Fabian Pianezzi Carolin M. Sutter‐Fella Lukas Kranz Debora Keller Harald Hagendorfer Yaroslav E. Romanyuk Fabio LaMattina Songhak Yoon Lassi Karvonen Theresa Magorian‐Friedlmeier Erik Ahlswede Dirk VanGenechten Fabrice Stassin Ayodhya N. Tiwari 《Progress in Photovoltaics: Research and Applications》2015,23(9):1110-1119
Large‐grained CuInSe2 absorber layers are synthesized using a non‐vacuum process based on nanoparticle ink precursors and selenization by rapid thermal processing (RTP). The use of hydroxide‐based particles in organic solvents allows for the conversion with elemental selenium without the need to employ explosive and/or toxic H2 or H2Se gasses. Lateral grain sizes up to 4 µm are obtained through a novel RTP route, overcoming the inherently high layer porosity for previous nanoparticle processes. Morphological and elemental characterization at interrupted selenization steps suggests that liquid selenium can play a beneficial role in promoting layer densification and grain growth. Long carrier collection lengths in CuInSe2 enable notable conversion efficiencies, despite the low minority carrier lifetimes of below 1 ns. Record efficiencies up to 8.73% highlight the potential of low‐cost, non‐vacuum deposition of chalcopyrite absorber layers with safe and simple precursors and processing routes. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献