Ana Hernández

Investigating the functioning of a middle category by means of a mixed-measurement model

Researchers have studied whether there are classes of people who differ systematically in the way they respond to polytomous ordered scales with a middle category such as ?. The mixed-partial credit model was fitted to a number of scales of a personality questionnaire. Most of the scales fit better with the use of 2 latent subpopulations. The most consistent difference among the latent classes was related to the functioning of the middle response category. For most of the examinees, the probability of choosing the middle category was very close to zero, but a nonnegligible percentage of people selected this category with much higher probability. The total scores from the 2 subpopulations were incommensurate. Some personality factors contributed to explaining class membership.

Climate uniformity: its influence on team communication quality, task conflict, and team performance

We investigated whether climate uniformity (the pattern of climate perceptions of organizational support within the team) is related to task conflict, team communication quality, and team performance. We used a sample composed of 141 bank branches and collected data at 3 time points. The results obtained showed that, after controlling for aggregate team climate, climate strength, and their interaction, a type of nonuniform climate pattern (weak dissimilarity) was directly related to task conflict and team communication quality. Teams with weak dissimilarity nonuniform patterns tended to show higher levels of task conflict and lower levels of team communication quality than teams with uniform climate patterns. The relationship between weak dissimilarity patterns and team performance was fully mediated by team communication quality. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Effects of protoscoleces and AgB from Echinococcus granulosus on human neutrophils: possible implications on the parasite’s immune evasion mechanisms

The factors affecting the innate susceptibility to Echinococcus granulosus infections are largely unknown. We assessed the interaction of healthy human neutrophils with protoscoleces (PSC) and antigen B (AgB) of E. granulosus by analysis of CD11b upregulation and H2O2 production by flow cytometry. PSC induced neutrophil activation, but their viability was not affected. In contrast, no effects were observed with AgB in both assays. Neutrophil-enriched fractions were also incubated with PSC or AgB, and interleukin 8 (IL-8) production was measured by ELISA. Significant increment in IL-8 production was detected only in supernatants from neutrophil-enriched fractions cultured with PSC. The possible effect of a prior incubation with AgB on the phorbol myristate acetate-induced activation was also evaluated. No changes were observed in CD11b expression, but the H2O2 production was significantly reduced in platelet-activating factor (PAF)-primed neutrophils. These results suggest a possible AgB-mediated mechanism of evasion of the host immune response, which would operate upon events of spillage of the fertile hydatid cyst content.

The Impact of Underemployment on Individual and Team Performance

The issue of underemployment is one of increasing concern for countries across the globe. For example, in the USA estimates have put the number of underemployed as high as 20.3%, while in Europe the number of overqualified workers (just one dimension of underemployment) has been estimated at 21.5% (Groot & Maassen van den Brink, 2000). Unfortunately, given the current global economic crisis, this situation can only be expected to worsen in the near future. The international labor pool is becoming more educated and qualified (Peiro, Agut, & Grau, 2010) while organizations worldwide are seeking the minimum effective level of human capitol in an effort to cut costs. As such fewer jobs demanding high levels of qualification are becoming available on the labor market while the supply of employees with just such a profile continues to grow.

Analysis of Multitrait-Multioccasion Data: Additive versus Multiplicative Models

The aim of this article is to address the question of whether empirical multitraitmultioccasion data conform more closely to multiplicative models than to additive models. Four additive models and two versions of the multiplicative Direct Product (DP) model (Browne, 1984) are tested. A set of 21 multitrait-multioccasion matrices is analyzed by means of LISREL 8 (Joreskog & Sorbom, 1993). The results obtained across different models are evaluated according to plausibility of solutions and goodness-of-fit. The different good-fitting models are compared in terms of goodness-of-fit and in terms of the conclusions about construct validity derived from the models. Results show that both additive and multiplicative models (specifically the additive Correlated Trait-Correlated Uniqueness model and the multiplicative Composite Direct Product model) usually fit the same MTMO data. Moreover both kinds of models are frequently equivalent in terms of goodness-of-fit. Finally, although general conclusions about construct validity are similar across models, the results obtained suggest that the conclusions about the relevance of each trait and occasion derived from additive and multiplicative models can differ substantially depending on the number of traits and occasions.

Testing the validity of the International Atomic Energy Agency (IAEA) safety culture model

This paper takes the first steps to empirically validate the widely used model of safety culture of the International Atomic Energy Agency (IAEA), composed of five dimensions, further specified by 37 attributes. To do so, three independent and complementary studies are presented. First, 290 students serve to collect evidence about the face validity of the model. Second, 48 experts in organizational behavior judge its content validity. And third, 468 workers in a Spanish nuclear power plant help to reveal how closely the theoretical five-dimensional model can be replicated. Our findings suggest that several attributes of the model may not be related to their corresponding dimensions. According to our results, a one-dimensional structure fits the data better than the five dimensions proposed by the IAEA. Moreover, the IAEA model, as it stands, seems to have rather moderate content validity and low face validity. Practical implications for researchers and practitioners are included.

Phenotypic analysis of peripheral lymphocyte subpopulations in hydatid patients

Abstract Peripheral T-lymphocytes were analyzed in three groups of people: (1) individuals with current liver hydatid disease (hydatid patients, n = 20), (2) persons who had undergone surgical cyst removal at least 2 years previously (recovered patients, n = 9), and (3) a control group of healthy volunteers (uninfected controls, n = 13). Group 1 was subdivided according to cyst status, relapse of disease, and the presence or absence of symptoms. Percentages of lymphocytes expressing CD3, CD4, CD8, CD56, CD25, CD45RA, CD45RO, and HLA-DR were determined. Symptomatic patients had proportionally fewer CD3+ CD8+ lymphocytes than the control group (P=0.038). Hydatid patients with active cysts had proportionally more natural killer cells (CD56+ CD8−) than the control group (P = 0.028).

Uncovering the dark side of innovation: the influence of the number of innovations on work teams’ satisfaction and performance

We investigated whether the number of innovations implemented in work teams is positively related to team task conflict and negative team mood, and whether the latter variables mediate the relationship between the number of innovations implemented and aggregate job satisfaction and team performance. The results obtained in a sample of 89 bank branches, where measures were obtained at three different times, partially supported our hypotheses. Whereas the number of innovations implemented had a positive direct effect on team performance, it had a negative indirect effect on team performance and aggregate job satisfaction, via negative team mood. These findings help uncover some of the dysfunctional consequences of innovation in work teams.

The exploratory factor analysis of items: guided analysis based on empirical data and software.

The aim of the present study is to illustrate how the appropriate or inappropriate application of exploratory factor analysis (EFA) can lead to quite different conclusions. To reach this goal, we evaluated the degree to which four different programs used to perform an EFA, specifically SPSS, FACTOR, PRELIS and MPlus, allow or limit the application of the currently recommended standards. In addition, we analyze and compare the results offered by the four programs when factor analyzing empirical data from scales that fit the assumptions of the classic linear EFA modeling adequately, ambiguously, or optimally, depending on the case, through the possibilities the different programs offer. The results of the comparison show the consequences of choosing one program or another; and the consequences of selecting some options or others within the same program, depending on the nature of the data. Finally, the study offers practical recommendations for applied researchers with a methodological orientation.

Nova era en el combat contra el càncer: evolució i càncer: progrés i tractament de tumors

L’oncohematologia ha assistit en les ultimes decades a importants avencos en el tractament i supervivencia. La toxicitat derivada de la quimioterapia classica i la necessitat de millorar l’eficacia i tolerancia als tractaments han fet que es desencadene un allau d’activitat investigadora que constantment proporciona fruits. Gran part d’aquest esforc s’ha enfocat al desenvolupament de «terapies diana» dirigides contra determinades alteracions funcionals, clau per a la supervivencia de la cel·lula tumoral. Aixi es preten aconseguir major eficacia en el tractament i que el pacient pague un menor cost en toxicitat. Avencos en altres disciplines de l’oncologia com l’epidemiologia, la cirurgia i la radioterapia dirigida han contribuit aixi mateix a fer de l’oncologia una area en progres constant. En definitiva, es comenca a albirar un futur ple d’esperanca per al pacient amb cancer, un futur, alhora, apassionant per al metge i l’investigador.