347 research outputs found

    Verification of the reflective model of first order factors for reward and empowerment constructs based on questionnaires derived from Lawler et al. (1991)

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    Purpose: High involvement practices have traditionally been classified in four main categories: training, communication, rewards and empowerment. In order to measure the degree of implementation of these programs, different questionnaires have been developed. In this paper, we have identified 3 types of questionnaires and we have deeply analyzed the psychometrical properties of one of these types: questionnaires derived from Lawler et al. (1991). The most recent investigation seems to show that psychometrical properties of both training and communication constructs are appropriate. However, it is necessary to work on rewards and empowerment scales. This research analyzes, by means of confirmatory factorial, two reflective measurement models, already present in the previous literature of rewards and empowerment scales. Design/methodology/approach: Spanish samples from 1997 (n=105), as well as United States ones (n=212 dating 1996 and n=143 dating 1999) have been used. Convergent and discriminant validity were tested. Findings and Originality/value: None of the models presents and acceptable adjustment in the used samples. Therefore, a possible future line of investigation in order to check whether the measurement model of rewards and empowerment constructs is formative instead of reflective, has been opened. Practical implications: Practitioners can profit from the results of this research because questionnaires validity will allow companies to have measurement and good practices diagnosis tools that can be used either for internal benchmarking or for the comparison with reference groups of companies. Originality/value: Our paper identifies three questionnaire typologies used in the field of investigations of rewards and empowerment practices. We show that the point of view with which the scales of theses questionnaires have been treated has always been reflective. Moreover, this is one of the few papers that have checked the validity of the measurement model of questionnaires derived from Lawler et al. (1991). It questions the validity of a single questionnaire with similar samples, of different years, and simultaneously, with samples from same years but from different countries.Peer Reviewe

    Estudio exploratorio de los programas de alta implicación de los operarios: identificación de las dimensiones y propuesta de un cuestionario para medir el grado de uso en las empresas

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    Actualmente, el debate sobre qué prácticas de recursos humanos se incluyen como prácticas de alta implicación de los operarios (High Involvement Work Practices) debería considerarse todavía abierto. En esta comunicación pretendemos hacer una revisión del marco teórico que nos permita identificar un conjunto de prácticas de alta implicación aceptado mayoritariamente y validar una propuesta de cuestionario que mida el grado de uso de las prácticas de alta implicación. La revisión teórica realizada nos ha permitido encontrar un conjunto de 27 prácticas relacionadas con la participación, comunicación, formación y compensación de los operarios y gestión del conocimiento. El análisis exploratorio de los datos nos permite presentar una agrupación alternativa de ítems en 7 escalas en lugar de las 5 que tradicionalmente se venían usando.At the moment, the debate about what human resources practices include as High Involvement Work Practices would have to be considered still open. In this communication we try to make a revision of the theoretical framework. This allows us to identify a set of practices mainly accepted as high involvement. We also validate a questionnaire proposal that measures the degree of use of these practices. The result of the theoretical revision has allowed us to find a set of 27 practices related to the participation, communication, training, compensation and management of the knowledge. The exploratory analysis of the data presents an alternative grouping of items in 7 scales instead of the traditional 5 ones.Peer Reviewe

    Development of a non-radioactive molecular hybridization probe for detecting Strawberry mottle virus in strawberry

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    La propagación vegetativa del cultivo de frutilla favorece la transmisión de patógenos sistémicos, como es el caso de los virus, que constituyen uno de los principales factores limitantes. Se han descripto más de 20 virus que infectan esta especie; el Strawberry mottle virus (SMoV) es uno de los más frecuentes y responsable de importantes pérdidas económicas. Debido a la falta de antisuero disponible comercialmente para un diagnóstico serológico, el SMoV es detectado fundamentalmente mediante reacción en cadena de la polimerasa con transcripción reversa (RT-PCR). En este estudio se desarrolló una sonda de hibridación molecular no radioactiva para su detección. Se sintetizó cDNA con cebadores específicos diseñados a partir de la región 3’ no codificante del genoma viral. El cDNA obtenido fue clonado, marcado y utilizado como sonda. Se evaluaron seis protocolos de extracción de ARN viral a partir de plantas infectadas, de los cuales el método de bromuro de cetiltrimetilamonio modificado (CTAB) fue el más eficiente. Se evaluaron hojas de diferentes estados fenológicos y pecíolos, y fueron las hojas viejas y los pecíolos los que mostraron mayor reacción.The vegetative propagation of strawberries favors transmission of systemicpathogens, such as viruses, which are one of the main yield-limiting factorsfor this crop. More than 20 viruses have been described as infecting thisspecies; one of the most frequent is the Strawberry mottle virus (SMoV), whichis responsible for significant economic losses. SMoV is usually detected byreverse transcription polymerase chain reaction (RT-PCR), given that serum isnot available for serological tests. In this study, a non-radioactive molecularprobe was developed for SMoV detection. The cDNA was synthesized byRT-PCR using specific primers designed from the 3?UTR region of the viralgenome. The cloned cDNA segment was labeled and used as a probe. Six RNAextraction protocols were evaluated, and the modified cetyltrimethylammoniumbromide (CTAB) method showed the highest sensitivity level. Leaves at differentphenological stages and petioles were evaluated; the highest reaction wasobserved in old leaves and in petioles.Fil: Asinari, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Cafrune, Eva Encarnacion. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Guzman, F. A.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Conci, Luis Rogelio. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Conci, Vilma Cecilia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin

    An annotated checklist of the jumping plant-lice (Insecta: Hemiptera: Psylloidea) from the Mercantour National Park, with seven new records for France and one new synonymy

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    A total of 68 psyllid species are listed from the Mercantour National Park in Southeast France, where a targeted collecting campaign was conducted between 2009 and 2012, as part of the project "ATBI+M" Mercantour. The insects were collected using Malaise traps, flight intercept traps and sweep nets to sample in the vegetation. Additional information on distribution, biology and host-plants is provided for each species. Seven species are recorded for the first time from France: Craspedolepta artemisiae (Foerster, 1848), Craspedolepta nebulosa (Zetterstedt, 1828), Cacopsylla propinqua (Schaefer, 1949), Cyamophila prohaskai (Priesner, 1927), Eryngiofaga cf. refuga (Loginova, 1966), Bactericera parastriola Conci, Ossiannilsson & Tamanini, 1988 and Trioza flixiana Burckhardt & Lauterer, 2002. Trioza (Trioza) rapisardai Conci & Tamanini, 1984 is a new subjective synonym of Trioza brachyceraea Hodkinson & White, 1979, which was previously known only from the male holotype. The abundance, distribution and introduction status of some species are discussed

    Conformational Isomerization Involving Conserved Proline Residues Modulates Oligomerization of the NS1 Interferon Response Inhibitor from the Syncytial Respiratory Virus

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    Interferon response suppression by the respiratory syncytial virus relies on two unique nonstructural proteins, NS1 and NS2, that interact with cellular partners through high-order complexes. We hypothesized that two conserved proline residues, P81 and P67, participate in the conformational change leading to oligomerization. We found that the molecular dynamics of NS1 show a highly mobile C-terminal helix, which becomes rigid upon in silico replacement of P81. A soluble oligomerization pathway into regular spherical structures at low ionic strengths competes with an aggregation pathway at high ionic strengths with an increase in temperature. P81A requires higher temperatures to oligomerize and has a small positive effect on aggregation, while P67A is largely prone to aggregation. Chemical denaturation shows a first transition, involving a high fluorescence and ellipticity change corresponding to both a conformational change and substantial effects on the environment of its single tryptophan, that is strongly destabilized by P67A but stabilized by P81A. The subsequent global cooperative unfolding corresponding to the main β-sheet core is not affected by the proline mutations. Thus, a clear link exists between the effect of P81 and P67 on the stability of the first transition and oligomerization/aggregation. Interestingly, both P67 and P81 are located far away in space and sequence from the C-terminal helix, indicating a marked global structural dynamics. This provides a mechanism for modulating the oligomerization of NS1 by unfolding of a weak helix that exposes hydrophobic surfaces, linked to the participation of NS1 in multiprotein complexes.Fil: Conci, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Álvarez Paggi, Damián Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: de Oliveira, Guilherme A. P.. Universidade Federal do Rio de Janeiro; BrasilFil: Pagani, Talita Duarte. Universidade Federal do Rio de Janeiro; BrasilFil: Esperante, Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Borkosky, Silvina Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Aran, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Alonso, Leonardo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Mohana Borges, Ronaldo. Universidade Federal do Rio de Janeiro; BrasilFil: de Prat Gay, Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentin

    Aphid species (Hemiptera: Aphididae) reported for the first time in Tucumán, Argentina

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    Aphids (Hemiptera: Aphididae) are considered among the most important pests all around the world. The total number of aphid species recorded in Argentina between 2003 and 2013 has risen from 200 to 237, which demonstrates the continuous introduction and discovery of new species in the territory. Therefore, faunistic studies should be conducted without interruption in areas of interest. The aim of this study was to establish if there were aphid species in Tucuman Province, Argentina that had not been recorded previously in the province. Aphids were collected with modified Moericke yellow water pan traps in potato crops during 2 seasons in 3 regions of Tucumán. Seventeen species, among the 47 species identified, and the genus Illinoia represent new records for the Province.Los pulgones se incluyen entre las plagas más importantes del mundo entero. El número total de especies de áfidos registrados en Argentina entre 2003 y 2013 se incrementó de 200 hasta 237, lo que demuestra la permanente introducción y hallazgo de nuevas especies en el territorio. Por lo tanto, son necesarios constantes estudios faunísticos en las áreas de interés. El objetivo de este estudio fue determinar si existían especies de áfidos en Tucumán, Argentina, que no habían sido citadas anteriormente en la provincia. Los pulgones se recolectaron con trampas amarillas de agua tipo Moericke durante dos temporadas de cultivo de papa, en tres regiones de Tucumán. Entre las 47 especies identificadas, 17 y el género Illinoia, representaron nuevas citas para la provincia.EEA MendozaFil: Avila, Ana Lucía. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Vera, M. Alejandro. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Ortego, Jaime. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; ArgentinaFil: Ploper, Leonardo Daniel. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Conci, Vilma Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Predictive visual search: Role of environmental regularities in the learning of context cues

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    Repeatedly searching through invariant spatial arrangements in visual search displays leads to the buildup of memory about these displays (contextual-cueing effect). In the present study, we investigate (1) whether contextual cueing is influenced by global statistical properties of the task and, if so, (2) whether these properties increase the overall strength (asymptotic level) or the temporal development (speed) of learning. Experiment 1a served as baseline against which we tested the effects of increased or decreased proportions of repeated relative to nonrepeated displays (Experiments 1b and 1c, respectively), thus manipulating the global statistical properties of search environments. Importantly, probability variations were achieved by manipulating the number of nonrepeated (baseline) displays so as to equate the total number of repeated displays across experiments. In Experiment 1d, repeated and nonrepeated displays were presented in longer streaks of trials, thus establishing a stable environment of sequences of repeated displays. Our results showed that the buildup of contextual cueing was expedited in the statistically rich Experiments 1b and 1d, relative to the baseline Experiment 1a. Further, contextual cueing was entirely absent when repeated displays occurred in the minority of trials (Experiment 1c). Together, these findings suggest that contextual cueing is modulated by observers' assumptions about the reliability of search environments
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