895 resultados para interpreting
Resumo:
To predict the response of aquatic ecosystems to future global climate change, data on the ecology and distribution of keystone groups in freshwater ecosystems are needed. In contrast to mid- and high-latitude zones, such data are scarce across tropical South America (Neotropics). We present the distribution and diversity of chironomid species using surface sediments of 59 lakes from the Andes to the Amazon (0.1–17°S and 64–78°W) within the Neotropics. We assess the spatial variation in community assemblages and identify the key variables influencing the distributional patterns. The relationships between environmental variables (pH, conductivity, depth, and sediment organic content), climatic data, and chironomid assemblages were assessed using multivariate statistics (detrended correspondence analysis and canonical correspondence analysis). Climatic parameters (temperature and precipitation) were most significant in describing the variance in chironomid assemblages. Temperature and precipitation are both predicted to change under future climate change scenarios in the tropical Andes. Our findings suggest taxa of Orthocladiinae, which show a preference to cold high-elevation oligotrophic lakes, will likely see range contraction under future anthropogenic-induced climate change. Taxa abundant in areas of high precipitation, such as Micropsectra and Phaenopsectra, will likely become restricted to the inner tropical Andes, as the outer tropical Andes become drier. The sensitivity of chironomids to climate parameters makes them important bio-indicators of regional climate change in the Neotropics. Furthermore, the distribution of chironomid taxa presented here is a vital first step toward providing urgently needed autecological data for interpreting fossil chironomid records of past ecological and climate change from the tropical Andes.
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Phylogenetic comparative methods are increasingly used to give new insights into the dynamics of trait evolution in deep time. For continuous traits the core of these methods is a suite of models that attempt to capture evolutionary patterns by extending the Brownian constant variance model. However, the properties of these models are often poorly understood, which can lead to the misinterpretation of results. Here we focus on one of these models – the Ornstein Uhlenbeck (OU) model. We show that the OU model is frequently incorrectly favoured over simpler models when using Likelihood ratio tests, and that many studies fitting this model use datasets that are small and prone to this problem. We also show that very small amounts of error in datasets can have profound effects on the inferences derived from OU models. Our results suggest that simulating fitted models and comparing with empirical results is critical when fitting OU and other extensions of the Brownian model. We conclude by making recommendations for best practice in fitting OU models in phylogenetic comparative analyses, and for interpreting the parameters of the OU model.
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In vitro fermentation techniques (IVFT) have been widely used to evaluate the nutritivevalue of feeds for ruminants and in the last decade to assess the effect of different nutritionalstrategies on methane (CH4) production. However, many technical factors may influencethe results obtained. The present review has been prepared by the ‘Global Network’ FACCE-JPI international research consortium to provide a critical evaluation of the main factorsthat need to be considered when designing, conducting and interpreting IVFT experimentsthat investigate nutritional strategies to mitigate CH4emission from ruminants. Given theincreasing and wide-scale use of IVFT, there is a need to critically review reports in the lit-erature and establish what criteria are essential to the establishment and implementationof in vitro techniques. Key aspects considered include: i) donor animal species and numberof animal used, ii) diet fed to donor animals, iii) collection and processing of rumen fluidas inoculum, iv) choice of substrate and incubation buffer, v) incubation procedures andCH4measurements, vi) headspace gas composition and vii) comparability of in vitro andin vivo measurements. Based on an evaluation of experimental evidence, a set of techni-cal recommendations are presented to harmonize IVFT for feed evaluation, assessment ofrumen function and CH4production.
Resumo:
Purpose: To compare baroreflex sensitivity among conscious rats of the same strain. Methods: Male WKY rats (eight weeks old) were studied. Cannulas were inserted into the abdominal aortic artery through the right femoral artery to measure mean arterial pressure (MAP) and heart rate (HR). Baroreflex gain was calculated as the ratio between variation of HR in function of the MAP variation (Delta HR/Delta MAP) tested with a depressor dose of sodium nitroprusside (SNP, 50 mu g/kg, iv) and with a pressor dose of phenylephrine (PE, 8 mu g/kg, iv). We divided the rats into four groups: 1) Low bradycardic baroreflex (LB), BG between -1 and -2 bpm/mmHg tested with PE; 2) High bradycardic baroreflex (HB), BG < -2 bpm/mmHg tested with PE; 3) Low tachycardic baroreflex (LT), BG between -1 and -2 bpm/mmHg tested with SNP and; 4) High tachycardic baroreflex (HT), BG < -2 bpm/mmHg tested with SNP. Significant differences were considered for p<0.05. Results: Approximately 82% of the rats presented reduced bradycardic reflex while 22 showed attenuated tachycardic reflex. No alterations were noted regarding basal MAP and HR, tachycardic and bradycardic peak and HR range. Conclusions: There was alteration in baroreflex sensitivity among rats of the same strain. Care should be taken when interpreting studies employing WKY as a control for the SHR.
Resumo:
In this study the baroreflex sensitivity of conscious, juvenile, spontaneously hypertensive rats (SHRs) was compared. The study population consisted of 19 eight-week-old male SHRs. The baroreflex sensitivity was quantified as the derivative of the variation in heart rate (HR) and the variation of mean arterial pressure (baroreflex sensitivity = Delta HR/Delta MAP). MAP was manipulated with sodium nitroprusside (SNP) and phenylephrine (PHE), administered via an inserted cannula in the right femoral vein. The SHRs were divided into four groups: (1) low bradycardic baroreflex (LB) where the baroreflex gain (BG) was between 0 and 1 bpm/mmHg with PHE; (2) high bradycardic baroreflex (HB), where the BG was < -1 bpm/mmHg with PHE; (3) low tachycardic baroreflex (LT) where the BC was between 0 and 3 bpm/mmHg with SNP; (4) high tachycardic baroreflex (HT) where the BG was > 3 bpm/mmHg with SNP. We noted that 36.8% of the rats presented with an increased bradycardic reflex, while 27.8% demonstrated an attenuated tachycardic reflex. No significant alterations were noted regarding the basal MAP and HR. There were significant differences in the baroreflex sensitivity between SHRs in the same laboratory. One should be careful when interpreting studies employing the SHR as a research model.
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Both continuum and emission line flickering are phenomena directly associated with the mass-accretion process. In this work we simulated accretion-disk Doppler maps, including the effects of winds and flickering flares. Synthetic flickering Doppler maps were calculated and the effect of the flickering parameters on the maps was explored. Jets and winds occur in many astrophysical objects where accretion disks are present. Jets are generally absent among the cataclysmic variables (CVs), but there is evidence of mass loss by wind in many objects. CVs are ideal objects to study accretion disks, and consequently to study the wind associated with these disks. We also present simulations of accretion disks, including the presence of a wind with orbital phase resolution. Synthetic Ha line profiles in the optical region were obtained and their corresponding Doppler maps were calculated. The effect of the wind simulation parameters on the wind line profiles was also explored. From this study we verified that optically thick lines and/or emission by diffuse material into the primary Roche lobe are necessary to generate single peaked line profiles, often seen in CVs. The future accounting of these effects is suggested for interpreting Doppler tomography reconstructions.
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We report on measurements of total cross sections (TCSs) for positron scattering from the fundamental organic molecule formaldehyde (CH(2)O). The energy range of these measurements was 0.26-50.3 eV, whereas the energy resolution was similar to 260 meV. To assist us in interpreting these data, Schwinger multichannel level calculations for positron elastic scattering from CH(2)O were also undertaken (0.5-50 eV). These calculations, incorporating an accurate model for the target polarization, are found to be in good qualitative agreement with our measured data. In addition, in order to compare the behaviour of positron and electron scattering from this species, independent atom model-screened additivity rule theoretical electron TCSs, now for energies in the range 1-10 000 eV, are also reported.
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Phototherapy improves cellular activation which is an important factor for the treatment of cellulite. The objective of this research was to develop and evaluate the effects of a new (noninvasive and nonpharmacological) clinical procedure to improve body aesthetics: infrared-LED (850 nm) plus treadmill training. Twenty women (25-55 years old) participated in this study. They were separated in two groups: the control group, which carried out only the treadmill training (n = 10), and the LED group, with phototherapy during the treadmill training (n - 10). The training was performed for 45 minutes twice a week over 3 months at intensities between 85% and 90% maximal heart rate (HR(max)). The irradiation parameters were 39 mW/cm(2) and a fluence of 106 J/cm(2). The treatment was evaluated by interpreting body composition parameters, photographs and thermography. This was primarily a treatment for cellulite with a reduction of saddlebag and thigh circumference. At the same time, the treadmill training prevented an increase of body fat, as well as the loss of lean mass. Moreover, thermal images of the temperature modification of the thighs are presented. These positive effects can result in a further improvement of body aesthetics using infrared-LED together with treadmill training.
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We investigate the possibility of interpreting the degeneracy of the genetic code, i.e., the feature that different codons (base triplets) of DNA are transcribed into the same amino acid, as the result of a symmetry breaking process, in the context of finite groups. In the first part of this paper, we give the complete list of all codon representations (64-dimensional irreducible representations) of simple finite groups and their satellites (central extensions and extensions by outer automorphisms). In the second part, we analyze the branching rules for the codon representations found in the first part by computational methods, using a software package for computational group theory. The final result is a complete classification of the possible schemes, based on finite simple groups, that reproduce the multiplet structure of the genetic code. (C) 2010 Elsevier Ltd. All rights reserved.
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Construction of identity and meaning is becoming increasingly important in both media studies and religion scholarship. (Lövheim, 2004) Meaning construction outside traditional religion has become more interesting for religious studies and what individuals in the audience do with all messages circulated through media in everyday life has attended increasing interest within media studies (Stout and Buddenbaum, 2001). Motion pictures, soap operas and advertising are all examples of media contents which generate ideas among its audience which to a various degree are used as resources within the construction of identity (Jansson, 2001). The investigation of what modern humankind’s world views look like and what components they are composed of, in this context seems to be an important topic of investigation (Holm and Björkqvist, 1996). The ways in which the development of media has effected the daily lives of individuals is interest as is the nature of the self and the ways in which the process of self-formation is affected by the profusion of mediated materials (Thompson, 1995). Film and religion are my interest within this larger frame. The topic is not exactly new but the combination of film and religion has during the last ten years resulted in a rapidly growing number of books by scholars interested in this field (Lyden, 2003). One growing focus is on the role that films can and do play within the emerging and developing valuesystem of people in the West today (Marsh, 2004). The British theologian Clive Marsh’s point of departure is very similar to my own. Viewers bring to a film life-experience, immediate concerns and worldviews and the exploration of this interplay between movies and the interpreting process of meaning making is the very focus in this paper. Theoretically, the semeiological model of Alf Linderman is combined with cultural cognitive approaches used by a number of Scandinavian media scholars developing perspectives in audience theory (Linderman, 1996, Höijer and Werner, 1998). 13 individuals, their favourite movie and what it means to them in their life My aim is to examine how individuals comprehend film and what the meaning process look like. In this paper I present the outcome of 13 interviews with young people about their favourite film. I suggest how it is possible to interpret how they interrelate film comprehension with their personal beliefs and their culturally constructed worldview from a sociocognitive point of view. Examples of films chosen range from Disneys Lion King (1994), sciencefiction and fantasy successes like The Matrix (1999) and Lord of the Rings (2001) or the next best movie ever according to www.IMdb.com The Shawshank Redemption (1994) as well as the Swedish blockbuster Så som i himmelen (2004), aka “As in Heaven”.
Resumo:
This litterature study is an analysis of the concept of tolerance, as it is a central value in the curriculum for the Swedish upper secondary school (Gy11) and therefore an important part of interpreting the specific curriculum for religious studies. The scientific approach is drawn from curriculum theory and the method of analysis is hermeneutic. Four different understandings of the concept are presented from academic literary sources. To further problematize the understandings of the concept, critique against a ”pedagogy of tolerance” as expressed by normcritical pedagogical writers and scholars is presented and analyzed. Implications regarding didactical practice are discussed in the light of previous analysis. Two main criteria for tolerance were found in all four understandings. These criterias outline the necessary components of an act of tolerance. The critique mainly focuses on said act, as it is an act of power and differentiation. This implies the didactical importance of awareness regarding the complexity of an act of tolerance.
Resumo:
Images are used in history education for a variety of reasons, not least to generate interest through a better understanding of historical events and people. The aim of this study was to investigate how historical pictures, either illustrated or documentary/photographic, can be used as a resource for activating and improving pupils' historical empathy, in the way described by Stéphane Lévasque. I conducted a reception study on five different focus groups consisting of pupils from different upper secondary schools in Sweden. The pupils varied with regard to number of credits for admission to upper secondary school. A sixth group of pupils was interviewed as a contrasting control group in order to add perspective to the results. The discussions were based on the pupils' interpretations of 34 selected pictures, all of which were taken from the most common history textbooks. Each pupil was asked to choose the picture he/she felt was the most representative historical image. On the basis of the strategies used by the pupils when interpreting the pictures and discussing them, the material was analysed in accordance with Lévesque's categories: imagination, historical contextualisation and morals. The last category, morals, was further divided into three sub-categories: sense of justice, sympathy and progression. The reflections of the pupils and the degree of contextualisation varied. It appeared that the pupils were less inclined to discuss assumptions about the persons in the pictures; instead they chose to discuss the historical context in question. The pictures in this study did not seem to trigger the pupils to fabricate anachronistic reasoning about history; when they did produce lengthy reasoning, it was contextual, structural and metahistorical. In this context, the pupils who belonged to the group with the highest average of credits showed some signs of reflection on the basis of historical context and some criticism about the historical sources. On no occasion did any of the pupils choose a picture as a concrete expression of injustice. One of the questions this study aimed to explore was whether a lack of historical context affects how pictures trigger emotions and reasoning on the basis of moral aspects. Some of the pupils displayed moral standpoints, primarily the degree of morals concerning injustice. One possible interpretation could be that the feeling of being unfairly treated and subjected to insulting behaviour and social injustice was something the pupils could relate to. The group of pupils who had not yet studied history at upper secondary school, the control group, generally made reflections using this sort of reasoning when they discussed the historical aspects of the pictures.
Resumo:
E-learning has become one of the primary ways of delivering education around the globe. In Somalia, which is a country torn within and from the global community by a prolonged civil war, University of Hargeisa has in collaboration with Dalarna University in Sweden adopted, for the first time, e-learning. This study explores barriers and facilitators to e-learning usage, experienced by students in Somalia’s higher education, using the University of Hargeisa as case study. Interviews were conducted with students to explore how University of Hargeisa’s novice users perceived elearning, and what factors positively and negatively affected their e-learning experiences. The Unified Theory of Acceptance and Use of Technology (UTAUT) model was used as a framework for interpreting the results. The findings show that, in general, the students have a very positive attitude towards e-learning, and they perceived that e-learning enhanced their educational experience. The communication aspect was found to be especially important for Somali students, as it facilitated a feeling of belonging to the global community of students and scholars and alleviated the war-torn country’s isolation. However, some socio-cultural aspects of students’ communities negatively affected their e-learning experience. This study ends with recommendations based on the empirical findings to promote the use and enhance the experience of e-learning in post conflict Somali educational institutions