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171.
Marisa D'Mello 《Information Technology for Development》2013,19(2):131-158
Global software organization (GSOs) are a recent form of work settings where Information Technology (IT) professionals engage in information and communication technology (ICT) mediated software development work for businesses across the globe. Issues of self, identity, and gender are linked to particularities of GSOs as a work setting. Using an interpretative, ethnographic approach, empirical data from a case study in India was analyzed to understand how gender was expressed in GSOs and linked to the concepts of self and identity of IT workers. Data suggests that GSOs are a global work setting where local issues of gender reflect social arrangements in Indian society. These arrangements have implications for GSOs as a work setting, for software development work, as well as for the selves and identities of IT workers. © 2005 Wiley Periodicals, Inc. 相似文献
172.
The photoreduction of Cu(II) in presence of an organic species as sacrificial agent has been investigated by many research groups but some controversial results are reported in literature. In this work, the photoreduction process of Cu(II) in presence of formic acid is investigated aiming at clarifying the reaction mechanism and assess the reaction kinetics. The effect of operating conditions such as TiO2 load, initial concentration of sacrificial agent, pH and ionic strength was studied. The results of the work are: (1) the system reactivity does not depend neither on pH (in the range 2.0-3.5) nor on ionic strength of the solution; (2) formic acid is adsorbed on TiO2 surface; (3) the nature of anionic species can influence the Cu(II) photoreduction (e.g. the addition of sulphate or phosphates reduces the reaction rates); and (4) FA can be completely mineralized during this photoxidation process; for example, this is observed for a TiO2 load of 0.1 g/L after a reaction time of about 240 min. A simplified kinetic model is developed to describe the behavior of the system and validated by analysing the data collected during the experimental work. 相似文献
173.
Llop S Ballester F Estarlich M Ibarluzea J Manrique A Rebagliato M Esplugues A Iñiguez C 《The Science of the total environment》2008,407(1):97-104
1-hydroxypyrene (1-OHP) is a biomarker of exposure to polycyclic aromatic hydrocarbons (PAHs). PAHs are pollutants produced by the combustion of organic material, and could be found both indoors and outdoors. Prenatal exposure to these compounds has been associated with retarded intrauterine growth and respiratory problems in children. The objective of this study is to describe the 1-OHP levels in urine in pregnant women in the INMA cohort in Valencia, and to study the association with socio-demographic and lifestyle variables, as well as with indicators of air pollution. The study population is a sub-sample (n: 204) of a cohort of pregnant women in the multicentre INMA project in Valencia (Spain). Urine samples were taken in week 12 of gestation, and 1-OHP was analyzed, and adjusted for creatinine. Socio-demographic and lifestyle information was collected using a questionnaire. Data from the monitoring stations in Valencia were used to assign levels of exposure to nitrogen dioxide (NO2), sulphur dioxide (SO2), total suspended particulates (TSP) and carbon monoxide (CO). The median 1-OHP level was 0.061 muicrool/mol of creatinine. Women who smoked had higher 1-OHP levels (0.095 micromol/mol of creatinine) than non-smokers (0.050 micromol/mol of creatinine). The variables predicting 1-OHP levels on linear multivariate analysis were: tobacco consumption, consumption of fried and smoked foods. There was also a significant association with NO2 levels 4 and 5 days before the samples were taken. The 1-OHP levels found in pregnant women in Valencia were higher than those found among women in reports in USA. 1-hydroxypyrene could be a good marker of exposure to PAHs from tobacco and diet, and also a useful marker of short term exposure to air pollution. 相似文献
174.
Infectivity and genome persistence of rotavirus and astrovirus in groundwater and surface water 总被引:1,自引:0,他引:1
Espinosa AC Mazari-Hiriart M Espinosa R Maruri-Avidal L Méndez E Arias CF 《Water research》2008,42(10-11):2618-2628
175.
Marisa Canterino Vincenzo Caprio Mario Iamarino Raffaele Marotta Vincenzo Tufano 《臭氧:科学与工程》2006,28(1):47-52
Ozonation is particularly suited for the treatment of recalcitrant soil contaminants. Clofibric acid, an active metabolite of some blood lipid regulators, was used as a model organic contaminant, and quartzite as a model soil. The measurements performed at different pHs, both in slurries of contaminated soil and in clofibric acid aqueous solutions, indicate that a markedly higher TOC removal can be obtained in the slurry mode. Ozonation kinetics in aqueous slurries was also studied in a well-mixed reactor. Suitable mathematical models were used to describe the experiments and to estimate the best values of the unknown parameters. 相似文献
176.
Federica Benvenuti Nazzareno Cannella Serena Stopponi Laura Soverchia Massimo Ubaldi Veronica Lunerti Valentina Vozella Bryan Cruz Marisa Roberto Roberto Ciccocioppo 《International journal of molecular sciences》2021,22(8)
Alcoholism is a chronically relapsing disorder characterized by high alcohol intake and a negative emotional state during abstinence, which contributes to excessive drinking and susceptibility to relapse. Stress, dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and alterations in glucocorticoid receptor (GR) function have been linked to transition from recreational consumption to alcohol use disorder (AUD). Here, we investigated the effect of pharmacological antagonisms of GR on alcohol self-administration (SA) using male and female Wistar and Marchigian Sardinian alcohol-preferring (msP) rats, a rodent line genetically selected for excessive alcohol drinking and highly sensitive to stress. Animals were trained to self-administer 10% (v/v) alcohol. Once a stable alcohol SA baseline was reached, we tested the effect of the GR antagonists mifepristone (0.0, 10, 30 and 60 mg/kg; i.p.) and CORT113176 (0.0, 10, 30 and 60 mg/kg) on alcohol SA. To evaluate whether the effects of the two compounds were specific for alcohol, the two drugs were tested on a similar saccharin SA regimen. Finally, basal blood corticosterone (CORT) levels before and after alcohol SA were determined. Systemic injection with mifepristone dose-dependently reduced alcohol SA in male and female Wistars but not in msPs. Administration of CORT113176 decreased alcohol SA in male and female Wistars as well as in female msPs but not in male msP rats. At the highest dose, mifepristone also reduced saccharin SA in male Wistars and female msPs, suggesting the occurrence of some nonspecific effects at 60 mg/kg of the drug. Similarly, the highest dose of CORT113176 (60 mg/kg) decreased saccharin intake in male Wistars. Analysis of CORT levels revealed that females of both rat lines had higher blood levels of CORT compared to males. Alcohol consumption reduced CORT in females but not in males. Overall, these findings indicate that selective blockade of GR selectively reduces alcohol SA, and genetically selected msP rats are less sensitive to this pharmacological manipulation compared to heterogeneous Wistars. Moreover, results suggest sex differences in response to GR antagonism and the ability of alcohol to regulate GR transmission. 相似文献
177.
Agustin Forchetti Casarino Santiago Andrés Bortolato Diana Alejandra Estenoz Marisa Elisabet Spontón 《Polymer Engineering and Science》2021,61(6):1611-1623
Novel polybenzoxazine/polysilsesquioxane nanocomposites were synthesized with uniform and reproducible structural morphology, high Tg, and good thermal stability. Polysilsesquioxane was oriented in a nanometer-size lamellar structure. Benzoxazine monomer based on silane (BA-3aptms) was synthesized by reaction between bisphenol A, 3-(trimethoxysilyl)propylamine, and paraformaldehyde in a 1:2:4 molar ratio. Four experimental conditions of the two stage sol–gel process for polysilsesquioxane were studied, and their effect on the material characteristics investigated. In the first stage, hydrolysis was favored, while the second stage mostly consisted of condensation. The reaction condition with the longest hydrolysis time allowed the increase of the concentration of silanol units and the selective condensation, favoring the formation of a higher amount of cage-like cyclic structures. In addition, this experimental procedure was well controlled so that the sol–gel and oxazine-ring opening reactions were extremely reproducible from batch to batch. All processes were monitored by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis and dynamic mechanical thermal analysis, scanning electron and transmission electron microscopies, and X-ray diffraction. A chemometric approach based on a multivariate curve resolution model was applied to the FTIR spectra, which allowed the identification of four reaction components associated with the sol–gel and the curing processes. 相似文献
178.
Adriano Costa de Camargo Marisa Aparecida Bismara Regitano-d’Arce Severino Matias de Alencar Solange Guidolin Canniatti-Brazaca Thais Maria Ferreira de Souza Vieira Fereidoon Shahidi 《Journal of the American Oil Chemists' Society》2016,93(8):1101-1109
The oxidative changes of peanuts subjected to the dry‐blanching process were evaluated and compared with those of their in‐shell counterparts. In general, the fatty acid profile was not influenced. The content of α‐tocopherol decreased, but the remaining tocopherol homologs were unaffected. Nonanal, an oxidation product of oleic acid, increased. However, the contents of several volatile compounds with potential antioxidant properties were also increased. The higher oxidative stability of dry‐blanched peanuts was demonstrated by accelerated tests as evaluated by peroxide value, thiobarbituric acid reactive substances (TBARS) and the induction period of cold‐pressed oils and this was confirmed by the higher antioxidant properties of oils from such sample as evaluated by the DPPH radical scavenging activity. These results were further confirmed during long‐term storage of dry‐blanched and in‐shell peanuts. The decrease of tocopherols in peanuts due to dry‐blanching did not negatively influence their oxidative stability. In fact, dry‐blanched peanuts showed higher stability as compared with in‐shell peanuts; therefore, we suggest that loss of tocopherol might be less important than the generation of several volatile antioxidant compounds as well as possibly Maillard reaction products upon the dry‐blanching process. These results may be of practical interest to the peanut and peanut oil industries. 相似文献
179.
Design of thermosetting polymeric systems based on benzoxazines modified with maleic anhydride 下载免费PDF全文
A novel benzoxazine (BzPFA) with carboxylic acid groups in its structure was synthesized in a two‐step process. First, BzPOH monomer was obtained from bisphenol A, paraformaldehyde, and ethanolamine with an initial molar ratio 1:4:2. Then, BzPOH was reacted with maleic anhydride using a stoichiometric 1:1 ratio of oxazine ring:maleic anhydride to produce a mixture of oligomeric species named BzPFA. The products were characterized by nuclear magnetic resonance, size‐exclusion chromatography, and Fourier transform infrared spectroscopy. BzPFA presented a weight‐average molecular weight of 50,000 g mol?1. Mixtures of the novel precursor and the conventional benzoxazine based on bisphenol A (BzBA) (60:40 and 40:60 weight ratios) were prepared and three different curing conditions were considered in order to study the effect of BzPFA on curing and final properties. Blends exhibited improved properties respect to BzBA even at relatively low curing temperatures. These results can be associated to the network crosslinked by ester bonds that promotes a high rigidity. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46183. 相似文献
180.
In this paper we provide foundations to contextual rewriting. We present the class of LOG-specifications, which may be seen, essentially, as a variety of conditional specifications, which may be seen, essentially, as a of LOG-specifications are LOG-algebras, i.e. algebras satisfying that their boolean part coincides with the boolean algebra of two elements. With respect to this semantics, a proof-system called L is presented characterizing logical consequence proof-theoretically. Then, we show that, under adequate assumptions of confluence and finite termination, contextual rewriting is a complete method for this kind of specifications.This work was partially done during the first author's stay at C.R.I.N., with financial support of the Spain-France Integrated Action 34/212. Research partially supported by a subcontract with SESA-Alcatel under the ESPRIT program in the project PROSPECTRA, ref # 390. 相似文献