2,836 research outputs found
Ability of Cistus L. shrubs to promote soil rehabilitation in extensive oak woodlands of Mediterranean areas
To assess the ecological function of Cistus salviifolius (CS) and C. ladanifer (CL) shrubs in evergreen oak woodlands, a study was conducted over a 4-year period in southern Portugal. Annual potential return of bio-elements to the soil through litterfall and throughfall, and necromass on soil surface under shrub canopies were assessed along with the dynamics of leaf litter decomposition. Soil bulk density and soil-water retention at different soil matric potential were measured at 0–5 and 5–10 cm depth, and soil chemical properties were determined at 0–5, 5–10, 10–20 and 20–30 cm depth beneath canopies and at barren spaces. Litterfall was higher for CL (4.4–4.6 Mg DM ha−1 year−1) than for CS (3.3–3.8 Mg DM ha−1 year−1). Annual amount of N returned to the soil through litterfall of CS (22.9 kg N ha−1 year−1) was higher than by that of CL (17.2 kg N ha−1 year−1), whereas the return of P in CL (4.1 kg P ha−1 year−1) was higher than in CS (2.1 kg P ha−1 year−1). Leaf decomposition was faster for CS (k= −0.87) than for CL (k=−0.44). N release was also faster for CS than for CL, while that of P was much faster for CL than for CS. Throughfall proportions were 61% of bulk rainfall for CS and 79% for CL. Annual return of Cl−, K+, Ca2+ and Mg2+ by throughfall was more pronounced for CL than for CS. Shrubs improved soil quality, especially in the 0–5 cm top soil layer, by enhancement of organic matter and nutrient content beneath shrub canopies. Therefore, shrubs may promote the invasion of more demanding species, since local areas of high fertility are likely to be favoured sites for vegetation regeneration
Pilot study into milk haptoglobin as an indicator of udder health in heifers after calving
Mastitis, inflammation of the mammary gland, is often caused by intramammary infection with bacterial organisms. It impacts on dairy cattle welfare, production, udder health and longevity in the herd. Current detection methods for mammary inflammation and infection all have limitations, particularly for on-farm diagnosis of non-clinical mastitis after calving. Acute phase proteins have been suggested as alternative early indicators of the disease and can potentially be used as cow-side test with results in real time. In this study, milk haptoglobin concentrations were investigated over the first week postpartum to explore haptoglobin's potential as indicator of udder health in dairy heifers. Haptoglobin concentration was highest on day 3 of lactation, and was positively correlated with somatic cell count, a commonly used marker of inflammation (rs=0.68). Haptoglobin level was also associated with bacteriological culture results, a key indicator of infection status, whereby median haptoglobin concentration on days 3 and 5 was higher in quarters that were infected at calving than quarters that were non infected at calving. Sensitivity and specificity of haptoglobin concentration as indicator of infection were low, both for lenient and strict culture-based definitions of intramammary infection (57 or 60% and 61 or 63%, respectively). Although haptoglobin was a poor biomarker for intramammary infection with coagulase negative staphylococci in heifers during the first week after calving, it may have value as an indicator of major pathogen infections, particularly in large scale dairy herds where pre-partum heifers are managed off-site
The relationship between responsible leadership and individual performance: Affective commitment and individual creativity as sequential mediators
In the last decade, responsible leadership (RL) has been gaining more interest in terms of research and practice. However, empirical evidence on its impacts on organizational and individual outcomes needs to be further explored (Haque et al., 2018, 2021; Waldman et al., 2020). RL is described as a way to build and maintain positive relationships with the organization's internal and external stakeholders, as well as responsibly coordinate actions to achieve a shared and meaningful business vision that contributes to sustainable value creation. and positive changes (Maak & Pless, 2006). As such, its potential positive outcomes from different stakeholders’ perspectives are diverse.
In what concerns employees, previous research found a direct and significant relationship between RL and individual performance (Lin et al., 2020; Simões & Duarte, 2021). That is, the adoption of a responsible leadership style seems to foster better individual performance. However, is not clear how the relationship is established and the cited authors pointed out the necessity to explore possible mediating and moderating variables.
Addressing this research gap, the current study explores the potential intervention of affective commitment and individual creativity as sequential mediators. Haque et al. (2018, 2021), Mousa (2017), and Simões and Duarte (2021) found a positive relationship between RL and affective commitment. Furthermore, Castro-González et al (2019) and Simões et al. (2021), also found a positive significant relationship between RL and individual creativity. The relationship between affective commitment and individual creativity has also been established (Leung & Lin, 2022; Ribeiro et al., 2020). Thus, affective commitment and individual creativity could emerge as potential psychological mechanisms that help explain the direct relationship between RL and individual performance.
A quantitative correlational study based on an electronic survey was conducted, collecting data from 260 employees from different organizations, through a non-probabilistic convenience sample. The questionnaire was based on self-report instruments developed to measure RL, affective commitment, individual creativity, and individual performance. All instruments revealed adequate reliability, as well as convergent and discriminant validity in the present sample.
The results from multiple regression analysis using PROCESS macro for SPSS indicated a positive and significant relationship between RL and individual performance. The indirect effect of affective commitment on the relationship between RL and individual performance was also significant, but the same did not happen with the indirect effect of individual creativity. Regarding the third indirect effect of the sequential effect of affective commitment and individual creativity at work on the relationship between RL and individual performance, it was positive and statistically significant. This indicates that RL contributes to strengthening the employee's affective commitment to the organization, which increases individual creativity at work, which, in turn, reinforces his/her individual performance at work. The model explains 32% of the variation in individual performance.
This means that both affective commitment and creativity, when combined, can help explain the relationship between the main variables of the model, indicating that the individuals' affective bond with the organization and their individual creativity are important variables that need to be considered by a responsible leader in order to influence desired results of their employees, such as improved individual performance.
As for the originality of this study, the literature had already found some evidence of the links between the variables in this research model but combining them on a sequential mediation offers a new perspective on the psychosocial process whereby the relationships between constructs are established.
In sum, this research suggests that RL can have a positive impact on the individual and, later, on an organizational level. Responsible leader presents themselves as a leader that can better communicate with their employees, build trusting relationships as well as integrate them into the decision-making process. These characteristics can then contribute to employees’ better work experiences, fostering their affective bond to the organization, their tendency to provide more useful and new ideas regarding work processes and results, and, thereby, improve their individual work performance.info:eu-repo/semantics/publishedVersio
O gênero Burkholderia: um importante componente da comunidade microbiana.
Descrição do gênero Burkholderia; Distribuição e diversidade; Patógenos em seres humanos e animais; Patógenos em plantas; Espécies diazotróficas em plantas não leguminosas; Espécies diazotróficas em plantas leguminosas; Promoção de crescimento em plantas; Controle biológico de doenças em plantas; Biorremediação.bitstream/CNPAB-2010/33991/1/doc219.pd
Dirac and Majorana heavy neutrinos at LEP II
The possibility of detecting single heavy Dirac and Majorana neutrinos at LEP
II is investigated for heavy neutrino masses in the range . We study the process as a clear signature for heavy neutrinos. Numerical estimates for
cross sections and distributions for the signal and the background are
calculated and a Monte Carlo reconstruction of final state particles after
hadronization is presented.Comment: 4 pages, 8 figure
a retrospective study of eighteen years
Leptospirosis, an under-recognized public health problem, needs to be confirmed through specific laboratory diagnosis. We describe herein a series of 4618 symptomatic patients for whom a microagglutination test (MAT) serology was available, representing a unique picture of human leptospirosis in central mainland Portugal and the Azores islands of São Miguel and Terceira, over eighteen- and twelve-year periods, respectively. The distribution of the 1024 (22%) cases identified was an average 57 cases per year, with higher frequency in males (67%). These represent the majority of leptospirosis notifications in Portugal, with a higher annual incidence rate in the islands, compared to the central mainland (11.1 and 1.7/100,000 population, respectively). Middle-aged adults (25-54 years) were most frequently infected (45%). Cases occurred mainly in December and January. Serovars from nine presumptive serogroups caused infection, with a predominance of Icterohaemorrhagiae, Pomona, and Ballum, accounting for 66% of cases. Seropositivity was associated with both anicteric and icteric leptospirosis. Several risk factors and a higher transmission risk in certain areas were emphasized. Leptospirosis was confirmed as a steadily increasing public health problem; good surveillance, communication, and laboratory support are thus necessary to reduce the impact of leptospirosis in areas at risk.publishersversionpublishe
Reevaluación de la tafonomÃa de las asociaciones conservadas in situ de Cloudina en la Formación de Tagatiya Guazu, Grupo ediacárico de Itapucumi, Paraguay
The fossil assemblage from the Tagatiya Guazu Formation (Ediacaran Itapucumi Group, Paraguay) represents a unique opportunity to investigate paleoecological parameters and contribute with taxonomic information regarding Cloudina associations in SW Gondwana.La asociación fósil de la Formación de Tagatiya Guazu (Grupo ediacárico de Itapucumi, Paraguay) representa una oportunidad única para investigar los parámetros paleoecológicos y contribuir con información taxonómica sobre las asociaciones de Cloudina en Gondwana SW
The relationship between responsible leadership and individual creativity: The role of affective commitment
Purpose: Leadership is one of the main topics in organizational behavior. Over the years, many researchers have studied the impact of different leadership styles on the attitudes and behaviors of employees. However, perhaps because it is a relatively recent construct, little research has been devoted to analyzing the effect that responsible
leadership has at the individual level of analysis (Haque et al., 2019, 2020; Miska & Mendenhall, 2018). Starting from the identification of this gap, the present research adopted an employee-centered approach to analyze how responsible leadership is related to individual creativity within the scope of a model that proposes affective commitment as a potential mediating mechanism. Recent research has found empirical support for the existence of a direct positive relationship between the variables (Castro-González et al., 2019). Research has also established a positive relationship between responsible leadership and affective commitment (Haque et al. 2019, 2020; Mousa,
2017; Simões & Duarte, 2021). Several studies on positive leadership styles have established affective commitment as a relevant mediating variable between leadership and employees’ attitudinal, emotional, and behavioral responses (Asif et al., 2019; Duarte et al., 2021). It is possible to theorize that responsible leadership, being also a positive leadership style, will find similar results, contributing to a greater employee emotional attachment to the organization, which will lead to more individual creativity behaviors at work.info:eu-repo/semantics/publishedVersio
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