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61.
This paper aims at testing the existence of yardstick competition by estimating a fully specified vote-function on a panel
data set of 104 French local governments from 1989 to 2001. When comparing the performance of their incumbent to the one of
their “neighbours”, voters might consider their close geographical neighbours but also the nearby cities that are similar
according to some socio-economic characteristics such as population size. The estimation results show that voters sanction
their incumbent if their own local housing tax is high. Moreover, we find that voters reward their incumbent when neighbouring
cities that are similar in terms of demographic characteristics have high local taxes. 相似文献
62.
Ertan Onur Yunus Durmus Mohamed Gamal Hawas Sonia Marcela Heemstra de Groot Ignas G. M. M. Niemegeers 《Wireless Personal Communications》2011,58(1):71-93
In this paper, we present a visionary concept referred to as Collaborative and Cognitive Network Platforms (CCNPs) as a future-proof
solution for creating a dependable, self-organizing and self-managing communication substrate for effective ICT solutions
to societal problems. CCNP creates a cooperative communication platform to support critical services across a range of business
sectors. CCNP is based on the personal network (PN) technology which is an inherently cooperative environment prototyped in
the Dutch Freeband PNP2008 and the European Union IST MAGNET projects. In CCNP, the cognitive control plane strives to exploit
the resources to better satisfy the requirements of networked applications. CCNP facilitates collaboration inherently. Through
cognition in the cognitive control plane, CCNP becomes a self-managed substrate. The self-managed substrate, in this paper,
is defined as cognitive and collaborative middleware on which future applications run without user intervention. Endemic sensor
networks may be incorporated into the CCNP concept to feed its cognitive control plane. In this paper, we present the CCNP
concept and discuss the research challenges related to collaboration and cognition. 相似文献
63.
Traditional input indicators of research performance, such as research funding, number of active scientists, and international
collaborations, have been widely used to assess countries’ publication output. However, while publication in today’s English-only
research world requires sound research in readable English, English proficiency may be a problem for the productivity of non-native
English-speaking (NNES) countries. Data provided by the Brazilian National Research Council (CNPq) containing the academic
profile of 51,223 Brazilian researchers show a correlation between English proficiency and publication output. According to
our results, traditional input indicators may fall short of providing an accurate representation of the research performance
of NNES developing countries. 相似文献
64.
Schwartz Sonia; Hoyte Joel; James Thea; Conoscenti Lauren; Johnson Renee; Liebschutz Jane 《Canadian Metallurgical Quarterly》2010,2(1):54
A dearth of literature exists on barriers to conducting research with Black male victims of community violence, despite the need for evidence-based postinjury interventions. This study used qualitative data from a cross-sectional interview study (n = 16) and a pilot intervention study (n = 11) conducted in Boston, MA to identify challenges and facilitators to conducting research with Black male victims of community violence, particularly with regard to recruitment and maintenance of a study sample. Qualitative methods, including Grounded Theory and ethnography, were used to analyze the data. Challenges included a fear of police involvement, an impression of “snitching” when disclosing personal information, mistrust of research motives, suspicion of the informed consent process, the emotional impact of the trauma itself, and logistical issues. Facilitators to research included monetary incentives and motivation to help oneself and others. Participant recommendations on recruitment methods relating to approach and timing are provided. Findings from this study may assist in the planning of research studies for Black male victims of community violence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
Salma Lasram Souheib Oueslati Ana Valero Sonia Marin Abdelwahed Ghorbel Vicente Sanchis 《Journal of food science》2010,75(2):M89-M97
ABSTRACT: This study investigated the effects of temperature (15 to 37 °C) and water activity (0.90 to 0.99) on the growth and production of ochratoxin A (OTA) by Aspergillus carbonarius cultured on synthetic nutrient medium (SNM) after 5 and 10 d of incubation. Total of 8 ochratoxigenic A. carbonarius, isolated from vineyards located in different regions of Tunisia, were used. Growth data were modeled by the flexible model of Baranyi and growth rates at each set of conditions were obtained. For both growth and OTA production, optimal water activity was 0.99; however, optimal temperature varied. The optimal temperature for growth was 30 °C. At 37 °C, the growth rate decreased significantly (P < 0.05). Maximum toxin production occurred at temperatures in the range of 15 to 25 °C with the optimum one depending on the isolate tested. Significant amounts of OTA were produced after only 5 d of incubation. Our results showed that A. carbonarius isolated from Tunisian grapes behave as those from European and Australian grapes, as reported in the literature, although some differences in trends for growth and OTA production were observed. 相似文献
66.
Sonia LevaAuthor Vitae 《Electric Power Systems Research》2011,81(1):193-201
A three-phase model of asynchronous machines operating at medium or high frequencies is presented. It can be used to study the propagation of surge waves along the stator windings of induction form wound machines.The model is derived from an analogy with a three-phase transmission line. The use of time-space Clarke vectors allows the introduction of mutual coupling between phases. The analytical expressions for voltage waves are derived by means of the Laplace approach to the solution of hyperbolic partial differential equations.Some applicative examples confirm the model validity and can underline some aspects of the project of three-phase windings. 相似文献
67.
Luiz F.G. Setz Isabel Santacruz M. Teresa Colomer Sonia R.H. Mello-Castanho Rodrigo Moreno 《Journal of the European Ceramic Society》2010,30(14):2897-2903
Lanthanum chromite (LaCrO3) is currently the most widely studied material as interconnector layers for solid oxide fuel cells (SOFC). The complexity of microstructures and geometries of SOFC devices, which are usually built-up by lamination of the different constitutive layers, make it necessary a precise control of processing parameters to achieve the desired combination of properties. Much effort has been devoted to the processing of electrodes and electrolytes but the other layers, such as that of interconnecting material, have received scarce attention. This work deals with the preparation and optimisation of the rheological behaviour of concentrated suspensions of Sr- and Co-doped LaCrO3 and the subsequent tape casting to produce homogeneous thin sheets to be used in the SOFC stack.The starting powder was produced by combustion synthesis from the corresponding nitrates and urea as a fuel, and had a final composition of La0.80Sr0.20Cr0.92Co0.08O3. These powders were dispersed in ethanol with commercial copolymers (Hypermer, KD6) to solids loading of up to 58 wt%. The binding system (BS) consisted of a mixture of a binder, polyvinyl butyral-co-vinyl alcohol-co-vinyl acetate (PVA-PVAc), and two plasticizers, polyethyleneglycol (PEG400) and benzylbutylphthalate (BBP). The effect of the binding system content and the binder-to-plasticizer ratio on the tape casting performance and the characteristics of the green and the sintered tapes, were studied, as well as the influence of the casting parameters (casting speed and blades height). 相似文献
68.
On the Mediation of Everything: ICA Presidential Address 2008 总被引:1,自引:0,他引:1
Sonia Livingstone 《The Journal of communication》2009,59(1):1-18
As our field moves beyond the traditional dualism of mass and interpersonal forms of communication to encompass new, interactive, networked forms of communication whose influence may be traced across multiple spheres of modern life, it is commonly claimed that "everything is mediated" and that this represents a historically significant change. This article inquires into these rhetorically grand claims: first, noting the parallels with other processes of mediation (e.g., language, money, and myths); second, raising questions of value since, unlike for other forms of mediation, the media's role is typically construed as negative rather than positive; and third, observing that the difficulties of translating "mediation" into a range of languages reveals some conceptual confusions. As a step toward clarification, I contrast the terms "mediation" and "mediatization," these roughly mapping onto situational and historical influences, conceived primarily at micro- and macrolevels of analysis, respectively. I then argue for a broad conception of mediation that encompasses those processes variously referred to as "mediatization,""mediazation," or "medialization." The analysis is illustrated by unpacking the claim that "childhood is mediated," before concluding that distinct aspects of the concept of mediation invite communication scholars to attend to the specific empirical, historical, and political implications of the claim that "everything is mediated." 相似文献
69.
We have applied scanning tunnelling microscopy (STM) to the study of two proteins: pseudoazurin and apo-pseudoazurin. Both proteins adsorbed onto a Au (1 1 1) surface are visible to STM individually, forming into layers and multilayers, with currents from about 55 to 600 pA. The images reproduce well the expected dimensions laterally but not in the z direction. The apparent height of the proteins varies with the voltage polarity, being higher at negative sample voltages. The bias also affects their shape. Negative sample voltages of more than 1.5 V orient the proteins present on a gold terrace in parallel rows. The layer of water adsorbed on surfaces in ambient conditions can be related to our results to explain the reduced z dimensions, the asymmetry with the voltage polarity and the alignment of proteins at voltages more negative than -1.5 V. 相似文献
70.
Prevalence of Clostridium botulinum in food raw materials used in REPFEDs manufactured in France 总被引:1,自引:0,他引:1
Carlin F Broussolle V Perelle S Litman S Fach P 《International journal of food microbiology》2004,91(2):141-145
Food raw materials used in refrigerated processed foods of extended durability (REPFEDs) manufactured in France were surveyed for Clostridium botulinum types A, B and E using PCR-Enzyme-linked Immunosorbent assay (PCR-ELISA) and mouse bioassay for detection respectively of cells and toxins in enrichment broth. Portions of 25 to 50 g of food were analysed. A total of 8 out of the 102 samples of fish and shellfish, 12 out of the 143 samples of meat and poultry, 1 out of the 62 samples of aroma, sauce and gravy, 4 out of the 25 samples of thickening agents, 3 out of the 26 samples of dehydrated dairy ingredients, and none of the 65 samples of spices, herbs and dehydrated mushroom were positive for C. botulinum in PCR-ELISA, i.e., 6.6% of all the samples tested. The 28 positive samples comprised 10 type A, 10 type B, 4 with both types A and B, and 4 undetermined by PCR typing. No sample positive for type E was detected. Of the 28 samples positive in PCR-ELISA, 15 were also positive in the mouse bioassay. The MPN count was between 1 and 3 C. botulinum/kg of food, which is similar to or in the lower range of values reported in the literature. 相似文献