898 resultados para Context effects (Psychology)


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The sustainable viticulture of a region passes, among other aspects, for maximizing the varieties potential minimizing subsequent interventions during winemaking, which should contribute to the production of quality wines maintaining their typicity and rationalizing costs. The detailed knowledge of each Appellation specificities, namely vineyard parcel (soil type and topographical peculiarities) and harvest climatic conditions is crucial for sustainability in this sector. Thus, in line with this current trend, the starting point for the development of this PhD thesis was to evaluate the oenological potential of different varieties cultivated throughout Bairrada Appellation (Portugal). During maturation several changes in grape varieties occur, namely berries become sweeter, less acidic, and they develop flavour, aroma and colour properties. The development of these characteristics is essential to define grapes oenological potential, i.e. to estimate the possibility of their usage to produce specific wines. A three years sampling plan was designed to evaluate the effect of harvest year and parcel characteristics on V. vinifera cv. Arinto, Bical, Sauvignon Blanc, Baga, Castelão, Touriga Nacional, and Sousão grapes composition. For each variety, 3 parcels with different characteristics were selected. Several physicochemical parameters were evaluated, during maturation: berry weight, pH, titratable acidity, sugar and phenolic contents, antiradical activity, and volatile composition (free fraction). Special attention was devoted to grapes at technologic maturity, since, besides these parameters, glycosidically-linked fraction was also considered. By using the results obtained at technologic maturity, a comprehensive approach was applied to identify the significance of harvest and parcel characteristics effects on each variety composition. Considering all the parameters under study, it may be highlighted some significant differences. According to the obtained results determined during maturation, it was possible to conclude that Arinto, Bical and Sauvignon Blanc grapes from parcels with clay-sandy and clay-calcareous soils have higher phenolic content and antiradical activity. Otherwise, Sauvignon Blanc presented similar volatile composition for grapes cultivated in the 3 parcels, while Arinto and Bical exhibited higher volatile content in grapes from claysandy and clay-calcareous soils. For Baga, Castelão and Touriga Nacional red varieties, grapes with higher phenolic content, antiradical activity, and volatile content were obtained from clayey and clay-calcareous soils. Furthermore, for Touriga Nacional, parcels altitude seems also to modulate grapes composition. Beyond parcel effect, harvest year conditions also influence grapes composition: 2011 harvest was related with lower phenolic and volatile contents, as well as lower antiradical activity.For grapes collected at technologic maturity, analysis of variance-simultaneous component analysis (ASCA) was applied combining all the parameters under study, in order to assess the influence of harvest and parcel characteristics on each variety oenological potential. The results obtained using this comprehensive approach is closely related with those observed during maturation and revealed that harvest was the main factor that influenced grapes composition (53% to 68% of the total data set variance) followed by parcel characteristics, explaining ca. 15-19% of the total data set variance. The oenological potential of each variety may be different from one parcel to another, i.e., clay-sandy and clay-calcareous related-environments seem to favour Arinto and Bical white grapes composition, but for the red varieties, grapes composition was favoured by clayey and clay-calcareous soils. Besides, also higher altitude seems to favour Touriga Nacional grapes composition. Sauvignon Blanc seems to be a variety well adapted to the different parcel characteristics. In order to go forward in the valuation of these varieties, the aroma properties of 6 monovarietal wines were studied based on an aroma network-approach, linking molecular data related to volatile composition and aroma data about the key odor active molecules. This approach allowed to identify different wine aroma properties and to infer about the consumer’s sensory perception. It was found that aroma properties differ from one wine variety to another: while Arinto and Sauvignon Blanc wine exhibited higher tree fruity, sweety and flowery aromas, related essentially with ester compounds and C13 norisoprenoids, the opposite was obtained for Bical wine, corroborating the aroma sensory perceptions of the trained panel. Sauvignon Blanc also exhibited higher toasted aromas (related with thiols, mainly with 2-methyl-3-furanthiol). Touriga Nacional red wine exhibited higher tree, tropical, and berry fruits notes (sensory described as sweet fruits), toasted and flowery aromas, while these are similar for the other red wines under study. Besides Portuguese Bairrada wines, this aroma network approach is a tool that can be used to explain the aroma properties of wines worldwide. The grape and wine data generated under the present PhD thesis, in the context of Bairrada Appellation, shows the unique character of each variety, and may be used by growers and wine producers as a support for decisionmaking based on objective criteria, increasing the sustainability in this sector. For instance, it is possible to take advantage of the natural resources and produce products with different characteristics obtained from the same variety, minimizing costs during the winemaking process.

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Environmental contamination and climate changes constitute two of the most serious problems affecting soil ecosystems in agricultural fields. Agriculture is nowadays a highly optimized process that strongly relies on the application of multiple pesticides to reduce losses and increase yield production. Although constituting, per se, a serious problem to soil biota, pesticide mixtures can assume an even higher relevance in a context of unfavourable environmental conditions. Surprisingly, frameworks currently established for environmental risk assessments keep not considering environmental stressors, such as temperature, soil moisture or UV radiation, as factors liable to influence the susceptibility of organisms to pesticides, or pesticide mixtures, which is raising increasing apprehension regarding their adequacy to actually estimate the risks posed by these compounds to the environment. Albeit the higher attention received on the last few years, the influence of environmental stressors on the behaviour and toxicity of chemical mixtures remains still poorly understood. Aiming to contribute for this discussion, the main goal of the present thesis was to evaluate the single and joint effects of natural stressors and pesticides to the terrestrial isopod Porcellionides pruinosus. The first approach consisted on evaluating the effects of several abiotic factors (temperature, soil moisture and UV radiation) on the performance of P. pruinosus using several endpoints: survival, feeding parameters, locomotor activity and avoidance behaviour. Results showed that these stressors might indeed affect P. pruinosus at relevant environmental conditions, thus suggesting the relevance of their consideration in ecotoxicological assays. At next, a multiple biomarker approach was used to have a closer insight into the pathways of damage of UV radiation and a broad spectrum of processes showed to be involved (i.e. oxidative stress, neurotoxicity, energy). Furthermore, UV effects showed to vary with the environment medium and growth-stage. A similar biomarker approach was employed to assess the single and joint effects of the pesticides chlorpyrifos and mancozeb to P. pruinosus. Energy-related biomarkers showed to be the most differentiating parameters since age-classes seemed to respond differently to contamination stress and to have different metabolic costs associated. Finally, the influence of temperature and soil moisture on the toxicity of pesticide mixtures was evaluated using survival and feeding parameters as endpoints. Pesticide-induced mortality was found to be oppositely affected by temperature, either in single or mixture treatments. Whereas chlorpyrifos acute toxicity was raised under higher temperatures the toxicity of mancozeb was more prominent at lower temperatures. By the opposite, soil moisture showed no effects on the pesticide-induced mortality of isopods. Contrary to survival, both temperature and soil moisture showed to interact with pesticides to influence isopods’ feeding parameters. Nonetheless, was however the most common pattern. In brief, findings reported on this thesis demonstrated why the negligence of natural stressors, or multiple stressors in general, is not a good solution for risk assessment frameworks.

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During the last century mean global temperatures have been increasing. According to the predictions, the temperature change is expected to exceed 1.5ºC in this century and the warming is likely to continue. Freshwater ecosystems are among the most sensitive mainly due to changes in the hydrologic cycle and consequently changes in several physico-chemical parameters (e.g. pH, dissolved oxygen). Alterations in environmental parameters of freshwater systems are likely to affect distribution, morphology, physiology and richness of a wide range of species leading to important changes in ecosystem biodiversity and function. Moreover, they can also work as co-stressors in environments where organisms have already to cope with chemical contamination (such as pesticides), increasing the environmental risk due to potential interactions. Therefore, the objective of this work was to evaluate the effects of climate change related environmental parameters on the toxicity of pesticides to zebrafish embryos. The following environmental factors were studied: pH (3.0-12.0), dissolved oxygen level (0-8 mg/L) and UV radiation (0-500 mW/m2). The pesticides studied were the carbamate insecticide carbaryl and the benzimidazole fungicide carbendazim. Stressors were firstly tested separately in order to derive concentration- or intensity-response curves to further study the effects of binary combinations (environmental factors x pesticides) by applying mixture models. Characterization of zebrafish embryos response to environmental stress revealed that pH effects were fully established after 24 h of exposure and survival was only affected at pH values below 5 and above 10. Low oxygen levels also affected embryos development at concentrations below 4 mg/L (delay, heart rate decrease and edema), and at concentrations below 0.5 mg/L the survival was drastically reduced. Continuous exposure to UV radiation showed a strong time-dependent impact on embryos survival leading to 100% of mortality after 72 hours of exposure. The toxicity of pesticides carbaryl and carbendazim was characterized at several levels of biological organization including developmental, biochemical and behavioural allowing a mechanistic understanding of the effects and highlighting the usefulness of behavioural responses (locomotion) as a sensitive endpoint in ecotoxicology. Once the individual concentration response relationship of each stressor was established, a combined toxicity study was conducted to evaluate the effects of pH on the toxicity of carbaryl. We have shown that pH can modify the toxicity of the pesticide carbaryl. The conceptual model concentration addition allowed a precise prediction of the toxicity of the jointeffects of acid pH and carbaryl. Nevertheless, for alkaline condition both concepts failed in predicting the effects. Deviations to the model were however easy to explain as high pH values favour the hydrolysis of carbaryl with the consequent formation of the more toxic degradation product 1- naphtol. Although in the present study such explanatory process was easy to establish, for many other combinations the “interactive” nature is not so evident. In the context of the climate change few scenarios predict such increase in the pH of aquatic systems, however this was a first approach focused in the lethal effects only. In a second tier assessment effects at sublethal level would be sought and it is expectable that more subtle pH changes (more realistic in terms of climate changes scenarios) may have an effect at physiological and biochemical levels with possible long term consequences for the population fitness.

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This study examines the Social Dominance Orientation of players of the online roleplaying game World of Warcraft. The World of Warcraft offers an opportunity to investigate social dominance and biological sex differences in an environment where there is no cultural dominance of one sex over another. Social Dominance Orientation has been found to be different between males and females, with males scoring higher. However, this might be the consequence of social context. To this end sex differences between male and female players were investigated in the World of Warcraft environment, as well as the effects of chosen character sex. Player sex and character sex were found to have effects on Social Dominance Orientation. These results add further support to claims that Social Dominance Orientation has the characteristics of a sexually selected disposition to acquire resources and out-compete rival groups.

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All research involving the psychoactive compound lysergic acid diethylamide (LSD) was terminated globally following its prohibition more than 50 years ago, though illicit use remained fairly stable. A considerable resurgence of research interest in LSD has received considerable attention in various publications and professional fora. One of the main applications considered is LSD-assisted psychotherapy to address a number of difficulties like end-of-life anxiety, addiction/alcoholism, post-traumatic stress, and depression. However, due to the highly contradictory nature of early research findings and division in the literature, one is left uncertain as to whether psychology as a profession is currently equipped to critically evaluate these advances, let alone embrace them. The purpose of the present study was to contribute to current psychological knowledge on long-term LSD use. A group of long-term LSD users who claimed beneficial use were the focus here. A mixed methods design was employed. 110 users completed an online survey assessing for demographics, patterns of use, and specific personality traits through three psychometric measures, Big Five Inventory (BFI), General Self Efficacy scale (GSE) and Satisfaction With Life Scale (SWLS). Eight individual interviews were also conducted and analysed by Thematic Analysis (TA). Gaining different perspectives on reality and increasing self- awareness appeared to be essential elements of the belief system that these non-problematic long-term LSD users adopted in order to make sense of their LSD use. Qualitative findings also suggested the existence of a common set of life values, rules and the adoption of a hierarchical system between LSD users. Novices appeared to be tutored and guided by elders whose presence and input was valued and who were listened to and respected. A role for ‘wiser/elder’ users as those imparting valuable knowledge to novices was therefore also suggested. The underlying aim may possibly be an attempt to minimise risks and maximise potential benefits of LSD use. A prospective role for LSD as a deterrent of substance misuse, a ‘gateway drug to no drugs’ was also hinted and remains in need of iv further investigation. Claims regarding beneficial LSD use and ‘change’ through LSD use were confirmed by the participant sample. No noteworthy differences between psychometric scores of the LSD-using group and those of the general population (as suggested by normative data comparisons) were found, possibly due to methodological limitations, especially considering the highly subjective nature of the LSD experience and its effects. The determining role of extra-pharmacological variables or ‘set and setting’ in the outcome of LSD use suggested in earlier literature was re-validated. Knowledge on their specific components was enriched, and a potentially significant value for adopting a flexible, adaptable and solution-focused mind-set in order to better manage the effects of LSD was highlighted. Due to the highly selected nature of the participant sample, present findings should serve as suggestions for further research in order to clarify the aforementioned issues and to make explicit the mechanisms by which they operate. The complex nature of LSD, its use and its effects have been re-confirmed here. It is imperative that the current knowledge base on the substance is enriched before LSD is introduced in a clinical psychology professional context.

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In cases involving unionization of graduate student research and teaching assistants at private U.S. universities, the National Labor Relations Board has, at times, denied collective bargaining rights on the presumption that unionization would harm faculty-student relations and academic freedom. Using survey data collected from PhD students in five academic disciplines across eight public U.S. universities, the authors compare represented and non-represented graduate student employees in terms of faculty-student relations, academic freedom, and pay. Unionization does not have the presumed negative effect on student outcomes, and in some cases has a positive effect. Union-represented graduate student employees report higher levels of personal and professional support, unionized graduate student employees fare better on pay, and unionized and nonunionized students report similar perceptions of academic freedom. These findings suggest that potential harm to faculty-student relationships and academic freedom should not continue to serve as bases for the denial of collective bargaining rights to graduate student employees.

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This article outlines the research design of a large‐scale, longitudinal research study in England intended to describe and explore variations in teachers' work, lives and their effects on pupils' educational outcomes. The study, funded by the Department for Education and Skills (DfES) and incorporated into the Teaching and Learning Research Programme (TLRP) as an ‘Associate Project’, used an innovative mixed‐methods research design to create case studies of 300 teachers in Years 2, 6 and 9. The research was conducted over three consecutive academic years and collected a wide range of data through interviews, questionnaire surveys of teachers' and pupils' views and assessment data on pupils' attainments in English and mathematics. The text summarises the main findings from the research in relation to four interconnected themes of the study: Professional Life Phases; Professional Identity; Relative Effectiveness; and Resilience and Commitment. The influence of school context, in terms of level of social disadvantage of pupil intake, is also investigated. Key findings and their implications for policy and practice are highlighted.

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Thesis (Ph.D.)--University of Washington, 2013

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Senior thesis written for Oceanography 444

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The University of Worcester states in its most recent strategic plan (2013 – 2018) a set of enduring values that guide and direct the activities of the institution. The first listed, and perhaps the most important value is the striving to be “an outstanding university at which to be a student”. This is further supplemented by values such as “to inspire our students to reach their full potential through excellent, innovative teaching, scholarship and research” (University of Worcester 2013: p.4). One of the many ways in which the institution strives to provide this outstanding educational experience is through regular engagement, both formal and informal, with students at a number of points in each semester. Regular experiences of collating formal and informal feedback has led to the identification of a common theme amongst Higher National Diploma (HND) students in the Institute of Sport and Exercise Sciences (ISES), where they consistently request ‘more practicals’. The ISES modules however are designed to incorporate a high degree of interaction, practical activities and tasks. This is especially important for those studying at HND level as research suggests differences in learning preferences exist when compared to undergraduate students, the former preferring a more tactile style of learning (Peters et al. 2008). Using an introductory Sport Psychology HND module as an example, practical activities and tasks are fully embedded in the taught sessions to enable contextual links to be made between the learning outcomes and their subsequent use. Examples of these include: a. interviewing athletes to produce a performance profile (Butler & Hardy 1992); b. completing psychometric instruments such as the Competitive State Anxiety Inventory-2 (CSAI-2) to measure competitive anxiety in sport (Martens et al. 1990) and demonstrate data collection and construct measurement; c. performing relaxation interventions on the students to demonstrate how specific techniques (in this instance, decreasing somatic anxiety) might work in practice; d. demonstrating how observational learning facilitates skill acquisition by creating experimental conditions that the students participate in, in teaching a new skill. Nevertheless owing to the students' previously stated on-going requests for more practical activities, it became evident that assumptions about what students consider an effective means of experiential or active learning in the context of sport-related disciplines of study needed to be investigated. This is where the opportunity to undertake an action research project arose, this being a practical method commonly employed in pedagogical enquiry to aid reflection on teaching and assessment practice for the purposes of working towards continuous improvement.

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This study explores the extent to which work and organizational (W&O) psychology practitioners use evidence, how they apply it to the everyday contexts in which they work and the types of barriers they encounter in so doing. It adopts a mixed methods approach involving the administration of a survey to a UK sample (N=163) of W&O psychologists and a series of semi-structured interviews (N=25) exploring in greater depth how evidence is applied in practice. Findings reveal that practitioners consult a wide range of different types of evidence which they employ at various stages of engagement with client organisations and that this evidence is pressed into service in the pursuit of solutions which are both acceptable from the client perspective and consistent with the scientific standards underpinning professional knowledge and expertise in W&O psychology. Barriers to evidence-use were mainly practical in nature, concerning issues around managing the client-consultant relationship and the particularities of implementation context, both of which were shown to influence evidence utilisation. The study contributes to current debate on the extent to which W&O psychologists adopt an evidence-based approach and provides a valuable and much called-for empirical insight into the enactment of the scientist-practitioner model in W&O psychology

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Bone is constantly being molded and shaped by the action of osteoclasts and osteoblasts. A proper equilibrium between both cell types metabolic activities is required to ensure an adequate skeletal tissue structure, and it involves resorption of old bone and formation of new bone tissue. It is reported that treatment with antiepileptic drugs (AEDs) can elicit alterations in skeletal structure, in particular in bone mineral density. Nevertheless, the knowledge regarding the effects of AEDs on bone cells are still scarce. In this context, the aim of this study was to investigate the effects of five different AEDs on human osteoclastic, osteoblastic and co-cultured cells. Osteoclastic cell cultures were established from precursor cells isolated from human peripheral blood and were characterized for tartrate-resistant acid phosphatase (TRAP) activity, number of TRAP+ multinucleated cells, presence of cells with actin rings and expressing vitronectin and calcitonin receptors and apoptosis rate. Also, the involvement of several signaling pathways on the cellular response was addressed. Osteoblastic cell cultures were obtained from femur heads of patients (25-45 years old) undergoing orthopaedic surgery procedures and were then studied for cellular proliferation/viability, ALP activity, histochemical staining of ALP and apoptosis rate. Also the expression of osteoblast-related genes and the involvement of some osteoblastogenesis-related signalling pathways on cellular response were addressed. For co-cultured cells, osteoblastic cells were firstly seeded and cultured. After that, PBMC were added to the osteoblastic cells and co-cultures were evaluated using the same osteoclast and osteoblast parameters mentioned above for the corresponding isolated cell. Cell-cultures were maintained in the absence (control) or in the presence of different AEDs (carbamazepine, gabapentin, lamotrigine, topiramate and valproic acid). All the tested drugs were able to affect osteoclastic and osteoblastic cells development, although with different profiles on their osteoclastogenic and osteoblastogenic modulation properties. Globally, the tendency was to inhibit the process. Furthermore, the signaling pathways involved in the process also seemed to be differently affected by the AEDs, suggesting that the different drugs may affect osteoclastogenesis and/or osteoblastogenesis through different mechanisms. In conclusion, the present study showed that the different AEDs had the ability to directly and indirectly modulate bone cells differentiation, shedding new light towards a better understanding of how these drugs can affect bone tissue.

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In the present longitudinal study, we investigated attachment quality in Portuguese mother–infant and in father–infant dyads, and evaluated whether attachment quality was related to parental sensitivity during parent–infant social interaction or to the amount of time each parent spent with the infant during play and in routine caregiving activities (e.g., feeding, bathing, play). The sample consisted of 82 healthy full-term infants (30 girls, 53 boys, 48 first born), and their mothers and fathers from mostly middle-class households. To assess parental sensitivity, mothers and fathers were independently observed during free play interactions with their infants when infants were 9 and 15 months old. The videotaped interactions were scored by masked coders using the Crittenden’s CARE-Index. When infants were 12 and 18 months old, mother–infant and father–infant dyads were videotaped during an adaptation of Ainsworth’s Strange Situation. Parents also described their level of involvement in infant caregiving activities using a Portuguese version of the McBride and Mills Parent Responsibility Scale. Mothers were rated as being more sensitive than fathers during parent–infant free play at both 9 and 15 months. There also was a higher prevalence of secure attachment in mother–infant versus father–infant dyads at both 12 and 18 months. Attachment security was predicted by the amount of time mothers and fathers were involved in caregiving and play with the infant, and with parents’ behavior during parent–infant free play.

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The aim of this study is to evaluate lighting conditions and speleologists’ visual performance using optical filters when exposed to the lighting conditions of cave environments. A crosssectional study was conducted. Twenty-three speleologists were submitted to an evaluation of visual function in a clinical lab. An examination of visual acuity, contrast sensitivity, stereoacuity and flashlight illuminance levels was also performed in 16 of the 23 speleologists at two caves deprived of natural lightning. Two organic filters (450 nm and 550 nm) were used to compare visual function with and without filters. The mean age of the speleologists was 40.65 (± 10.93) years. We detected 26.1% participants with visual impairment of which refractive error (17.4%) was the major cause. In the cave environment the majority of the speleologists used a head flashlight with a mean illuminance of 451.0 ± 305.7 lux. Binocular visual acuity (BVA) was -0.05 ± 0.15 LogMAR (20/18). BVA for distance without filter was not statistically different from BVA with 550 nm or 450 nm filters (p = 0.093). Significant improved contrast sensitivity was observed with 450 nm filters for 6 cpd (p = 0.034) and 18 cpd (p = 0.026) spatial frequencies. There were no signs and symptoms of visual pathologies related to cave exposure. Illuminance levels were adequate to the majority of the activities performed. The enhancement in contrast sensitivity with filters could potentially improve tasks related with the activities performed in the cave.

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The effects of PMSs on the people’s behaviour represent a high degree of relevance in the context of an organization performance and success. Thus, motivational and behavioural consequences of performance measurements are far from being totally understood (Franco-Santos et al., 2012). This work project (WP) purposes going further regarding the consequences/effects on people’s behaviour of using PMSs in organizations. The researcher conducted 11 interviews to managers during a nine-month internship as a controller in a Portuguese multi-national company. The evidence from this WP suggests that the way how managers understand a PMS determines a lot the way how they behave. Data also supports that PMSs influences in several ways motivation, perceptions, participation and job-related stress of managers.