961 resultados para two-to-one trapdoor functions
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The objective of this study is to gather information regarding the adaptation of the range of socio educational projects and services aimed at the transition to an adult life of young persons with intellectual disabilities in Spain. The research of the study has been done in three stages. During each stage, a specific tool has been used. One to one in-depth interviews have been undertaken with 45 professionals and 20 individuals with intellectual disabilities. The Delphi method has been applied to two panels consisting of 20 experts each. Firstly, results focus on the approach to different issues related to the devices. Secondly, the training opportunities that these individuals receive to ease the transition period is addressed. And finally, the study refers to the participation of the individuals themselves and their families in the process. The developed analysis allows us to propose strategies to improve the transition to adult life
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This study aimed to investigate the ideal brood area to be introduced for strengthening Apis mellifera colonies, considering variations in the hive's internal ambience. Therefore, eight colonies were equipped with data loggers for recording variations in temperature and humidity inside the hives. Then, these colonies were split in four treatments involving the swapping of four, three, two and one brood comb between strong and weak colonies. Growth in the amount of brood and food stores to the four colony strengthening treatments was assessed counting the comb cells to record changes in the brood and food area. The colonies tended to restore their normal thermoregulation within four hours after they had been manipulated and the hive cover had been closed, which quickly increased brood area in the receiving colonies. Results showed that adding up to three brood combs constitute an important alternative for strengthening Apis mellifera colonies because it did not interfere with nest thermoregulation, speeded up population growth in weak colonies and did not affect the development of strong colonies.
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OBJECTIVE: to develop an experimental model of exposure to tobacco burning (cigarette) products to assess the effects of its chronic use in relation to cancers of the bladder. METHODS: the animals were chronically exposed to the burning tobacco products in a semi-open chamber to simulate smoking. Thirty young Wistar rats were divided into two groups: one with 20 animals simulating smoking for six months, and ten not exposed control animals for the same period. After exposure by inhalation of cigarette smoke, animals were euthanized and subjected to histopathological study of the bladder wall. RESULTS: no tumor was found but mild and non significant alterations. The studies of hemo-oximetry (carboxyhemoglobin and methemoglobin) and the concentration of carbon dioxide (CO2) confirm that the animals were exposed to high concentrations of tobacco smoke and its derivatives. CONCLUSION: no bladder mucosal neoplasia was found in the pathological study of animals. The developed experimental models were highly efficient, practical and easy to use and can be used in other similar studies to determine the harmful effects caused by smoking.
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Cells communicate, or signal, with each other constantly to ensure proper functioning of tissues and organs. Cell signaling is often performed by interplay of receptors and ligands that bind these receptors. ErbB receptors (epidermal growth factor receptors, EGFR, HER) bind extracellular growth factors and transduce these signals inside of cells. ErbB dysfunction promotes carcinogenesis, and also results in numerous defects during normal development. This study focused on the functions of one member of the ErbB receptor family, ErbB4, and growth factor, neuregulin-1 (NRG-1), that can bind and activate ErbB4. This study aimed to find novel functions of ErbB4 and NRG-1. Hypoxia, or deficiency of oxygen, is common in cancer and ischemic conditions. One of the key findings of the work was the identification and characterization of a cross-talk between ErbB4 and Hypoxia-inducible factor 1α (HIF-1α), the central mediator of hypoxia signaling. ErbB4 activation by NRG-1 was found to increase HIF-1α activity. Interestingly, this regulation occurred in reciprocal manner as HIF-1α was also able to increase protein levels of NRG-1 and ErbB4. Moreover, expression of NRG-1 and ErbB4 was associated with HIF activity in vivo in human clinical samples and in mice. Reduction of functional ErbB4 in developing zebrafish embryos resulted in defects in development of the skeletal muscles. To study ErbB4 functions in pathological situation in humans, clinical samples of serous ovarian carcinoma were analyzed using tissue microarrays and real-time RT-PCR. A specific isoform of ErbB4, CYT-1, was associated with poor survival in serous ovarian cancer and increased anchorage independent growth of ovarian cancer cells in vitro. These observations demonstrate that ErbB4 and NRG-1 are essential regulators of cellular response to hypoxia, of development, and of ovarian carcinogenesis.
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We examined the ecological distribution of macroalgal communities in streams using species groups (taxonomic units = algal phyla, and morphological = morphological types) with similar structures and functions instead of the species themselves. The study was conducted from June to July/2007 in two drainage basins located in mid-southern region of Paraná State , Brazil. Evaluations of macroalgal communities took into consideration the following spatial scales: the drainage basin (the Pedras river and Marrecas river basins), shading regime (open and shaded stream segments), mesohabitats (riffles and pools), and microhabitats (sampling units of 0.05m2). A total of 29 taxa (23 subgeneric, one generic, and five vegetative groups) were identified. On these, 12 taxa belong to Chlorophyta, 11 to Cyanobacteria, four to Heterokontophyta, and two to Rhodophyta. The proportions of morphological types were: 24% free filaments, 17.25% mats, tufts, gelatinous colonies, and gelatinous filaments, 7% crusts. In terms of spatial scales, we observed a predominance of Chlorophyta in open stream segments and Cyanobacteria in shaded stream segments, reflecting the loss of competitive advantage of green algae in sites with low energy availability. In the mesohabitats, the morphological types recorded in pools were predominantly poorly adapted to fast currents (free filaments), while those found in riffles (mats, tufts and gelatinous filaments) were highly resistant to fast water flows. As such, the use of species groupings based on algal taxonomy associated with morphological characteristics proved to be useful to understanding the distributions of these organisms in lotic environments.
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Teaching, research, and herd breeding applications may require calculation of breed additive contributions for direct and maternal genetic effects and fractions of heterozygosity associated with breed specific direct and maternal heterosis effects. These coefficients can be obtained from the first NB rows of a pseudo numerator relationship matrix where the first NB rows represent fractional contributions by breed to each animal or group representing a specific breed cross. The table begins with an NB x NB identity matrix representing pure breeds. Initial animals or representative crosses must be purebreds or two-breed crosses. Parents of initial purebreds are represented by the corresponding column and initial two-breed cross progeny by the two corresponding columns of the identity matrix. After that, usual rules are used to calculate the NB column entries corresponding to breeds for each animal. The NB entries are fractions of genes expected to be contributed by each of the pure breeds and correspond to the breed additive direct fractions. Entries in the column corresponding to the dam represent breed additive maternal fractions. Breed specific direct heterozygosity coefficients are entries of an NB x NB matrix formed by the outer product of the two NB by 1 columns associated with sire and dam of the animal. One minus sum of the diagonals represents total direct heterozygosity. Similarly, the NB x NB matrix formed by the outer product of columns associated with sire of dam and dam of dam contains breed specific maternal heterozygosity coefficients. These steps can be programmed to create covariates to merge with data. If X represents these coefficients for all unique breed crosses, then the reduced row echelon form function of MATLAB or SAS can be used on X to determine estimable functions of additive breed direct and maternal effects and breed specific direct and maternal heterosis effects
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Early stimulation has been shown to produce long-lasting effects in many species. Prenatal exposure to some strong stressors may affect development of the nervous system leading to behavioral impairment in adult life. The purpose of the present work was to study the postnatal harmful effects of exposure to variable mild stresses in rats during pregnancy. Female Holtzman rats were submitted daily to one session of a chronic variable stress (CVS) during pregnancy (prenatal stress; PS group). Control pregnant rats (C group) were undisturbed. The pups of PS and C dams were weighed and separated into two groups 48 h after delivery. One group was maintained with their own dams (PS group, N = 70; C group, N = 36) while the other PS pups were cross-fostered with C dams (PSF group, N = 47) and the other C pups were cross-fostered with PS dams (CF group, N = 58). Pups were undisturbed until weaning (postnatal day 28). The male offspring underwent motor activity tests (day 28), enriched environment tests (day 37) and social interaction tests (day 42) in an animal activity monitor. Body weight was recorded on days 2, 28 and 60. The PS pups showed lower birth weight than C pups (Duncan's test, P<0.05). The PS pups suckling with their stressed mothers displayed greater preweaning mortality (C: 23%, PS: 60%; c2 test, P<0.05) and lower body weight than controls at days 28 and 60 (Duncan's test, P<0.05 and P<0.01, respectively). The PS, PSF and CF groups showed lower motor activity scores than controls when tested at day 28 (Duncan's test, P<0.01 for PS group and P<0.05 for CF and PSF groups). In the enriched environment test performed on day 37, between-group differences in total motor activity were not detected; however, the PS, CF and PSF groups displayed less exploration time than controls (Duncan's test, P<0.05). Only the PS group showed impaired motor activity and impaired social behavior at day 42 (Duncan's test, P<0.05). In fact, CVS treatment during gestation plus suckling with a previously stressed mother caused long-lasting physical and behavioral changes in rats. Cross-fostering PS-exposed pups to a dam which was not submitted to stress counteracted most of the harmful effects of the treatment. It is probable that prenatal stress plus suckling from a previously stressed mother can induce long-lasting changes in the neurotransmitter systems involved in emotional regulation. Further experiments using neurochemical and pharmacological approaches would be interesting in this model.
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The objective of the present study was to compare the effect of acute exercise performed at different intensities in relation to the anaerobic threshold (AT) on abilities requiring control of executive functions or alertness in physically active elderly females. Forty-eight physically active elderly females (63.8 ± 4.6 years old) were assigned to one of four groups by drawing lots: control group without exercise or trial groups with exercise performed at 60, 90, or 110% of AT (watts) and submitted to 5 cognitive tests before and after exercise. Following cognitive pretesting, an incremental cycle ergometer test was conducted to determine AT using a fixed blood lactate concentration of 3.5 mmol/L as cutoff. Acute exercise executed at 90% of AT resulted in significant (P < 0.05, ANOVA) improvement in the performance of executive functions when compared to control in 3 of 5 tests (verbal fluency, Tower of Hanoi test (number of movements), and Trail Making test B). Exercising at 60% of AT did not improve results of any tests for executive functions, whereas exercise executed at 110% of AT only improved the performance in one of these tests (verbal fluency) compared to control. Women from all trial groups exhibited a remarkable reduction in the Simple Response Time (alertness) test (P = 0.001). Thus, physical exercise performed close to AT is more effective to improve cognitive processing of older women even if conducted acutely, and using a customized exercise prescription based on the anaerobic threshold should optimize the beneficial effects.
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We have described a case of a patient with an intriguing association of mucocutaneous leishmaniasis with lepromatous leprosy, two opposite polar forms of these spectral diseases. In the present follow-up study, we investigated the effect of the addition of Mycobacterium leprae antigens on interferon-gamma (IFN-γ) production in Leishmania antigen-stimulated cultures of peripheral blood mononuclear cells (PBMC) from this patient. For this purpose, PBMC cultures were stimulated with crude L. braziliensis and/or M. leprae whole-cell antigen extracts or with concanavalin A. In some experiments, neutralizing anti-human interleukin (IL)-10 antibodies were added to the cultures. IFN-γ and IL-10 levels in culture supernatants were measured by ELISA. During active leprosy, M. leprae antigens induced 72.3% suppression of the IFN-γ response to L. braziliensis antigen, and this suppression was abolished by IL-10 neutralization. Interestingly, the suppressive effect of M. leprae antigen was lost after the cure of leprosy and the disappearance of this effect was accompanied by exacerbation of mucosal leishmaniasis. Considered together, these results provide evidence that the concomitant lepromatous leprosy induced an IL-10-mediated regulatory response that controlled the immunopathology of mucosal leishmaniasis, demonstrating that, in the context of this coinfection, the specific immune response to one pathogen can influence the immune response to the other pathogen and the clinical course of the disease caused by it. Our findings may contribute to a better understanding of the Leishmania/M. leprae coinfection and of the immunopathogenesis of mucosal leishmaniasis.
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Aino Toiviainen Probiotics and oral health: in vitro and clinical studies University of Turku, Faculty of Medicine, Institute of Dentistry, Periodontology, Finnish Doctoral Program in Oral Sciences (FINDOS-Turku), Turku, Finland Annales Universitatis Turkuensis, Sarja – Ser. D, Medica-Odontologica. Painosalama Oy, Turku, Finland, 2015 Probiotics are used, for example, to prevent and treat diarrhea, allergies and respiratory infections, and there is an increasing interest to use probiotics also for oral health purposes. The most commonly used probiotic bacteria are lactobacilli and bifidobacteria, which are acidogenic and aciduric. From the oral point of view, use of these probiotics may, at least in theory, mean an increased risk of caries. In this thesis, the effects of probiotics on oral microbial composition, acid production of dental plaque and gingival health were studied through in vitro studies and two clinical studies. In a randomized, double-blind and crossover study, 13 healthy adults were allocated into two groups. Half of the subjects first consumed Lactobacillus rhamnosus GG tablets twice a day for two weeks, and after the washout period, L. reuteri tablets twice a day for two weeks. The other half of the subjects used the tablets in reverse order. In another controlled, randomized and double-blind study, 62 healthy adults were allocated into two groups. One group used the test tablets containing L. rhamnosus GG and B. lactis BB-12 and the other group used control tablets without probiotics. The recommendation for the use of the tablets was 4 per day for 4 weeks. Probiotic lactobacilli interfered with S. mutans biofilm formation and the adhesion of S. mutans to saliva-coated hydroxyapatite in vitro. No effect was found in S. mutans levels in the three-species biofilms. In clinical studies, the studied probiotics had no effect on the acid production of plaque. The counts of mutans streptococci and the oral microbial composition remained the same. Tablets containing L. rhamnosus GG and Bifidobacterium animalis subsp. lactis BB-12 did decrease the amount of plaque and gingival bleeding. According to our results, it seems that probiotics have beneficial effects on gingival health. The present results confirmed that probiotics are safe and have beneficial effects on oral health. Since the consumption of probiotics by the general population is steadily increasing, an understanding of the functions of probiotics in the oral cavity has become more important. Keywords: lactobacilli, bifidobacteria, caries, periodontal disease, mutans streptococci, probiotics
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In this work we look at two different 1-dimensional quantum systems. The potentials for these systems are a linear potential in an infinite well and an inverted harmonic oscillator in an infinite well. We will solve the Schrödinger equation for both of these systems and get the energy eigenvalues and eigenfunctions. The solutions are obtained by using the boundary conditions and numerical methods. The motivation for our study comes from experimental background. For the linear potential we have two different boundary conditions. The first one is the so called normal boundary condition in which the wave function goes to zero on the edge of the well. The second condition is called derivative boundary condition in which the derivative of the wave function goes to zero on the edge of the well. The actual solutions are Airy functions. In the case of the inverted oscillator the solutions are parabolic cylinder functions and they are solved only using the normal boundary condition. Both of the potentials are compared with the particle in a box solutions. We will also present figures and tables from which we can see how the solutions look like. The similarities and differences with the particle in a box solution are also shown visually. The figures and calculations are done using mathematical software. We will also compare the linear potential to a case where the infinite wall is only on the left side. For this case we will also show graphical information of the different properties. With the inverted harmonic oscillator we will take a closer look at the quantum mechanical tunneling. We present some of the history of the quantum tunneling theory, its developers and finally we show the Feynman path integral theory. This theory enables us to get the instanton solutions. The instanton solutions are a way to look at the tunneling properties of the quantum system. The results are compared with the solutions of the double-well potential which is very similar to our case as a quantum system. The solutions are obtained using the same methods which makes the comparison relatively easy. All in all we consider and go through some of the stages of the quantum theory. We also look at the different ways to interpret the theory. We also present the special functions that are needed in our solutions, and look at the properties and different relations to other special functions. It is essential to notice that it is possible to use different mathematical formalisms to get the desired result. The quantum theory has been built for over one hundred years and it has different approaches. Different aspects make it possible to look at different things.
Resumo:
In this work we look at two different 1-dimensional quantum systems. The potentials for these systems are a linear potential in an infinite well and an inverted harmonic oscillator in an infinite well. We will solve the Schrödinger equation for both of these systems and get the energy eigenvalues and eigenfunctions. The solutions are obtained by using the boundary conditions and numerical methods. The motivation for our study comes from experimental background. For the linear potential we have two different boundary conditions. The first one is the so called normal boundary condition in which the wave function goes to zero on the edge of the well. The second condition is called derivative boundary condition in which the derivative of the wave function goes to zero on the edge of the well. The actual solutions are Airy functions. In the case of the inverted oscillator the solutions are parabolic cylinder functions and they are solved only using the normal boundary condition. Both of the potentials are compared with the particle in a box solutions. We will also present figures and tables from which we can see how the solutions look like. The similarities and differences with the particle in a box solution are also shown visually. The figures and calculations are done using mathematical software. We will also compare the linear potential to a case where the infinite wall is only on the left side. For this case we will also show graphical information of the different properties. With the inverted harmonic oscillator we will take a closer look at the quantum mechanical tunneling. We present some of the history of the quantum tunneling theory, its developers and finally we show the Feynman path integral theory. This theory enables us to get the instanton solutions. The instanton solutions are a way to look at the tunneling properties of the quantum system. The results are compared with the solutions of the double-well potential which is very similar to our case as a quantum system. The solutions are obtained using the same methods which makes the comparison relatively easy. All in all we consider and go through some of the stages of the quantum theory. We also look at the different ways to interpret the theory. We also present the special functions that are needed in our solutions, and look at the properties and different relations to other special functions. It is essential to notice that it is possible to use different mathematical formalisms to get the desired result. The quantum theory has been built for over one hundred years and it has different approaches. Different aspects make it possible to look at different things.
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Multiple measures have been devised by clinicians and theorists from many different backgrounds for the purpose of assessing the influence of the frontal lobes on behaviour. Some utilize self-report measures to investigate behavioural characteristics such as risktaking, sensation seeking, impulsivity, and sensitivity to reward and punishment in an attempt to understand complex human decision making. Others rely more on neuroimaging and electrophysiological investigation involving experimental tasks thought to demonstrate executive functions in action, while other researchers prefer to study clinical populations with selective damage. Neuropsychological models of frontal lobe functioning have led to a greater appreciation of the dissociations among various aspects of prefrontal cortex function. This thesis involves (1) an examination of various psychometric and experimental indices of executive functions for coherence as one would predict on the basis of highly developed neurophysiological models of prefrontal function, particularly those aspects of executive function that involve predominantly cognitive abilities versus processes characterized by affect regulation; and (2) investigation of the relations between risk-taking, attentional abilties and their associated characteristics using a neurophysiological model of prefrontal functions addressed in (1). Late adolescence is a stage in which the prefrontal cortices undergo intensive structural and functional maturational changes; this period also involves increases in levels of risky and sensation driven behaviours, as well as a hypersensitivity to reward and a reduction in inhibition. Consequently, late adolescence spears to represent an ideal developmental period in which to examine these decision-making behaviours due to the maximum variability of behavioural characteristics of interest. Participants were 45 male undergraduate 18- to 19-year olds, who completed a battery of measures that included self-report, experimental and behavioural measures designed to assess particular aspects of prefrontal and executive functioning. As predicted, factor analysis supported the grouping of executive process by type (either primarily cognitive or affective), conforming to the orbitofrontal versus dorsolateral typology; risk-taking and associated characteristics were associated more with the orbitofrontal than the dorsolateral factor, whereas attentional and planning abilities tended to correlate more strongly with the dorsolateral factor. Results are discussed in light of future assessment, investigation and understanding of complex human decision-making and executive functions. Implications, applications and suggestions for future research are also proposed.
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Youth-Adult Partnerships (Y-APs) have been found to foster youth engagement and positive youth development. However, existing research tends to confound the characteristics of Y-APs with their general outcomes and the existing methods of evaluating Y-APs tend to be based on correlational methodologies. I sought to create a measure of Y-AP success that did not confound the characteristics of a successful Y-AP with outcomes. Using the existing literature as a guide, three components were selected for inclusion in the Y-AP success measure: 1) perceptions of productivity; 2) positive affect; and 3) having one's contributions welcomed and considered. Using this new measure, I tested a model to assess how adult warmth and expertise interacted with task difficulty to influence three components of Y-AP success. Participants included 402 university students (M = 19.27, SD = 1.28, 89.1 % female) from Brock University and Cape Breton University. Video clips of an adult, depicting all possible combinations of warmth and expertise were created for this study, as well as a pair of hypothetical tasks designed to elicit differential degrees of perceived difficulty. Participants were exposed to one video of a hypothetical adult and two hypothetical tasks and responded to the Y-AP success measures twice, for each ofthe tasks. Results from mixed-model ANOVAs revealed that the adult and task characteristics were not consistently related to all components of Y-AP success. However, several significant interactions suggested that youth perceptions of task difficulty and their impressions of adult partners influenced the extent to which they expected a Y-AP to be successful. The results are discussed in the context of how they support or conflict with the existing literature and serve as a first step in the inference of causality within the study of Y-APs.
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In this thesis I assess the individual and joint predictive associations and effects between multiple motivation and well-being concepts. In particular, three pairs of motivation concepts (intrinsic/extrinsic, approach/avoidance, and eudaimonic/hedonic) are assessed simultaneously at two levels of analysis (disposition and goal) and examined in relation to two types of well-being (eudaimonic and hedonic) in two studies, one correlational and the other experimental. Study 1: Using a correlational design, participants (N = 325, M age = 19.10, 87% female) completed self-report measures assessing six motivation and two well-being concepts. Exploratory factor analyses were used to assess patterns of associations among the motivational constructs. Results indicated that constructs displaying conceptual and empirical similarities co-occur, particularly, intrinsic, approach and eudaimonic motivation. Regression models were used to assess predictive relations between the motivational constructs and well-being. Both types of well-being were predicted by approach and avoidance dispositions, and hedonic goals. Additionally, eudaimonic well-being was uniquely predicted by eudaimonic dispositions and goals, and intrinsic dispositions; and hedonic well-being was uniquely predicted by extrinsic dispositions and approach goals. The patterns of associations among motivational constructs, and similarities and differences in the ways they predict each type of well-being, are discussed. Study 2: Using an experimental design, participants (N = 447, M age = 19.30, 88% female) were randomly assigned to one of eight experimental conditions, each involving a manipulation aimed at priming combinations of the three pairs of motivational constructs at the goal level. Participants then completed measures of both types of well-being. ANOVAs were used to assess the main effects and interactions of experimental condition for each of the three pairs of motivational constructs on well-being. Main effects of experimental conditions were non-significant. However, results indicated that focus on each of the three pairs of motivational constructs predicted well-being and that the manipulation impacted well-being indirectly, through experimentally-shifted motivational focus. Few interactions emerged. Implications for future experimental research and the conceptual integration of motivation and well-being constructs are discussed. In conclusion, Studies 1 and 2 inform the motivation and well-being fields in novel ways and provide preliminary steps towards studying these fields from an integrated and comprehensive motivational framework.