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Dificuldades de alunos ingressantes na universidade pública: alguns indicadores para reflexões sobre a docência universitária; First-year students' difficulties in public universities: signals of the need of reflections about university teaching.

Belletati, Valéria Cordeiro Fernandes
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/06/2011 PT
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75.23%
A elitização da universidade pública brasileira é a preocupação central desta investigação. Com os programas de inclusão social, tem-se possibilitado maior representatividade de alunos em condições socioeconômicas desfavoráveis nestas instituições. Na Universidade de São Paulo USP, locus escolhido para esta pesquisa, o Programa de Inclusão Social INCLUSP, desde 2007, tem favorecido a entrada de alunos que cursaram todo o ensino médio em escolas públicas, majoritariamente constituída por alunos em condições menos favorecidas da sociedade brasileira. Teve-se como objetivo trazer elementos que possibilitassem pensar a docência universitária no sentido de favorecer trajetórias acadêmicas de sucesso destes alunos, entendidas como possibilidade de formação profissional, científica e política, função que atribuímos à universidade pública, que se entende concretizar-se na promoção do ensino profissional indissociado da pesquisa e da extensão. Para tanto, realizou-se a coleta de dados por meio de dois questionários abertos, respondidos por escrito pelos sujeitos, em momentos diversos. Com o primeiro questionário buscou-se identificar dificuldades de alunos ingressantes que cursaram todo o ensino médio comum em escolas públicas. Na segunda etapa...

The social function of the public library in the world of social networks and of the crisis of the Welfare State

Alvim, Luísa; Calixto, José António
Fonte: 5th International Conference on Qualitative and Quantitative Methods in Libraries 4 - 7 June 2013, "La Sapienza" University, Rome Italy Publicador: 5th International Conference on Qualitative and Quantitative Methods in Libraries 4 - 7 June 2013, "La Sapienza" University, Rome Italy
Tipo: Aula
POR
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85.18%
Currently we discuss the model of the Welfare State. In its genesis, this model intended to create a sense of belonging and of a cohesive community, concerned with the construction of a more equitable society through the redistribution of richness and attention to the most vulnerable population. Europe has a past of developing economic policies which led to the building of a society with legal and constitutional recognition of social rights after the Second World War, emphasizing the concept of citizenship. The current economic crisis has installed the debate on the performance of the state organizations and their social role. The public library as a state organization has a social function linked. This study aims to review the theoretical perspectives of several authors on the social function of the public library and to identify a connection between the presence of public libraries in virtual social networks and their condition towards the weakening or strengthening of the social responsibility that they carry, taking as a set the current discussion of the model of the welfare state and the generalized economic crisis. This work is part of a wider research on the impact of Web 2.0 on the social role of the Portuguese public libraries observed in the social network Facebook.

The catalytic function of the Rev1 dCMP transferase is required in a lesion-specific manner for translesion synthesis and base damage-induced mutagenesis

Zhou, Ying; Wang, Jillian; Zhang, Yanbin; Wang, Zhigang
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
EN
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75.21%
The Rev1-Polζ pathway is believed to be the major mechanism of translesion DNA synthesis and base damage-induced mutagenesis in eukaryotes. While it is widely believed that Rev1 plays a non-catalytic function in translesion synthesis, the role of its dCMP transferase activity remains uncertain. To determine the relevance of its catalytic function in translesion synthesis, we separated the Rev1 dCMP transferase activity from its non-catalytic function in yeast. This was achieved by mutating two conserved amino acid residues in the catalytic domain of Rev1, i.e. D467A/E468A, where its catalytic function was abolished but its non-catalytic function remained intact. In this mutant strain, whereas translesion synthesis and mutagenesis of UV radiation were fully functional, those of a site-specific 1,N6-ethenoadenine were severely deficient. Specifically, the predominant A→G mutations resulting from C insertion opposite the lesion were abolished. Therefore, translesion synthesis and mutagenesis of 1,N6-ethenoadenine require the catalytic function of the Rev1 dCMP transferase, in contrast to those of UV lesions, which only require the non-catalytic function of Rev1. These results show that the catalytic function of the Rev1 dCMP transferase is required in a lesion-specific manner for translesion synthesis and base damage-induced mutagenesis.

The effect of smooth muscle antagonists on the sound-induced motion of the tympanic membrane

Graves, Amanda J. (Amanda Jean)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 83 p.; 4100541 bytes; 4104673 bytes; application/pdf; application/pdf
ENG
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85.15%
The pars tensa of the tympanic membrane is composed of three layers: an epidermal layer, a fibrous layer, and a mucosal layer. Recent studies (Kuijpers et al, 1999; Henson and Henson, 2000; Henson et al, 2005) suggest that the fibrous layer in several mammalian species contains contractile fibers, which are located primarily within the thickened border of the pars tensa known as the annulus fibrosis. These contractile fibers resemble smooth muscle fibers. Yang and Henson (2002) studied the physiological effects of pharmacological modulators on the pars tensa of the annulus fibrosis by measuring the sound-induced cochlear response. Their results suggest a dose-dependent change in cochlear response after application of sodium orthovanadate and norepinephrine. Application of saline induced no change in cochlear response. Based on their data, Yang and Henson proposed that the pharmacological agents altered the function of the smooth muscle fibers of the annulus fibrosis to produce a mechanical change in the tympanic membrane. In this study two measurements, cochlear response and Laser Doppler Vibrometry, were used to assess the sound-induced velocity of the tympanic membrane of the gerbil before and after application of saline and varying concentrations of three smooth muscle antagonists (sodium orthovanadate...

Nierentransplantation am Klinikum Tübingen: Relevante Parameter für die Transplantatfunktion; Renal Transplantation at the Sugigical Department of the University of Tübingen: relevant parameters for the long term graft function

Schmid, Birte
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
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75.24%
In der vorliegenden retrospektiven Studie wurden 119 Nierentransplantationen, welche zwischen 2000-2005 an der Chirurgischen Klinik des Universitätsklinikums Tübingen durchgeführt wurden, hinsichtlich der langfristigen Organfunktion des Transplantats untersucht. Grundlage für die Evaluierung der Organfunktion waren die in der ambulanten Nachsorge ermittelten Serumkreatininwerte. Messzeitpunkte waren postoperativ und 3, 12 bzw. 36 Monate nach Transplantation. Als einflussnehmende Parameter wurden u.a. die demographischen Spender- und Empfängerdaten, Spendertyp, Dialysedauer und Primärerkrankung des Empfängers, sowie die transplantationsassoziierten Parameter Anastomosenzeit (AZ), Kalte Ischämiezeit (CIT) und initialer Funktionsstatus erfasst und analysiert. Als relevante Parameter für eine langfristige Organfunktion der am UKT verpflanzten Nieren erwiesen sich vor allem Spendergeschlecht und Spendertyp. Transplantate von weiblichen Spendern zeigten hochsignifikant den schlechteren Outcome. Ein Vergleich mit internationalen Daten und Studien ergab ähnliche Ergebnisse. Nach Gründen hierfür wird noch geforscht. Als ursächlich werden unter anderem Sexualhormone diskutiert. Ein zusätzlicher Einflussfaktor für den geschlechtsbedingten schlechteren Outcome der weiblichen Spendernieren in Tübingen könnte die Tatsache sein...

Toward the structure and function of carbon-phosphorus lyase enzymes

He, ShuMei
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 4062570 bytes; application/pdf
EN; EN
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75.24%
Organophosphonates are characterized by a very stable carbon-phosphorus bond. Eshcherichia coli and many other strains of bacteria possess a multi-enzyme system called carbon-phosphorus (C-P) lyase that enables these organisms to cleave the C-P bond of organophosphonates when inorganic phosphate is scarce in the local environment. Genetic studies have demonstrated that C-P lyase is encoded by the fourteen-gene phn operon, phnCDEFGHIJKLMNOP. However, the mechanism for C-P bond cleavage is still unclear. We have expressed, purified, and characterized phnP from this operon. PhnP is a phosphodiesterase which will hydrolyze both bis-(p-nitrophenyl) phosphate and 2’:3’-cyclic nucleotides as substrates. In collaboration with Dr. Zongchao Jia and Katarenya Podzelinska (Queen’s Biochemistry), we have crystallized phnP and solved the crystal structure at a resolution of 1.3 Å. The structure displayed similarity to zinc-dependent metallo-β-lactamase family proteins. However, phnP displays unique structural features with two metal binding sites per monomer: the active site containing potentially two manganese ions, and a ‘structural’ site coordinating one zinc ion. Potential active site residues were identified and corresponding point mutations were generated by site-directed mutagenesis. Studies based on the importance of these residues and the knowledge from our high resolution structure will help elucidate the mechanism of phnP as well as its function in the C-P lyase pathway. Furthermore...

Investigating the contribution of the frontal cortex in executive control in normal versus abnormal aging

PELTSCH, Alicia J
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
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85.24%
The proportion of elderly individuals in society is increasing dramatically, leading to an increase in the prevalence of age-related neurological disorders that affect the function of the frontal lobes and overall movement control. This thesis aims to evaluate ‘executive control’ and the underlying brain changes in normal versus abnormal aging processes using saccadic eye movement tasks. Tasks performed by subjects that probe executive control consist of antisaccades (generate a voluntary eye movement after inhibiting an automatic movement to a visual stimulus), and memory-guided saccades (generate eye movements to three previous remembered visual stimuli in the same sequence they were presented). Both of these types of saccades require good functioning behavioural control, which is subserved by areas in the prefrontal cortex. This thesis specifically characterizes the changes in oculomotor control related to aging, Huntington’s disease, mild cognitive impairment (amnestic), and Alzheimer’s disease. We also specifically examine the neural mechanisms related to behavioural control in the antisaccade task in aging. Together, the conclusions drawn from this thesis reveal that specific areas in the prefrontal cortex are involved in executive dysfunction in both normal and abnormal aging...

The Objective/Subjective Distinction of the Self: Examining Self-Discrepancy

Silver, ARIEL
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
75.24%
Self-discrepancies have traditionally been measured with the Selves Questionnaire. This is an objective measure, in that it does not assume that individuals are aware of the discrepancies between their various self-state representations. The purpose of this research project was to examine a new method of measuring self-discrepancy: simply asking individuals for their subjective views of their self-discrepancies. These studies aimed to show that objective and subjective measures tap into distinct constructs which function differently depending on the level of deliberation of the testing conditions. The attitudes literature, from which this distinction was borrowed, provided groundwork to predict that subjective self-discrepancy would function better under conditions of deliberation whereas objective self-discrepancy would function better under conditions of spontaneity. In Study 1, both measures of self-discrepancy were used to predict agitation. This study showed that the objective and subjective measures were indeed only modestly correlated with one another. As expected, subjective ought self-discrepancy was a significant predictor of agitation under deliberative but not spontaneous conditions. Contrary to predictions, subjective ideal but not objective ought self-discrepancy significantly predicted agitation under spontaneous conditions. Study 2 predicted dejection from both measures of self-discrepancy...

OBESITY AND ENDOTHELIAL FUNCTION: INVESTIGATING THE IMPORTANCE OF THE SHEAR STRESS STIMULUS PROFILE USED FOR FMD ASSESSMENT

Slattery, DAVID
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
75.24%
Endothelial function is important for the maintenance of vascular health and it can be assessed by measuring endothelial dependent flow mediated dilation (FMD) in response to an imposed increase in shear stress (SS). While the 5 min reactive hyperemia FMD test (5 min RH-FMD) of the brachial artery (BA) remains the most commonly employed method of increasing shear stress, other methods, including handgrip exercise (HGEX), also exist. The purpose of this study was to determine whether obesity is associated with a uniform, or a SS profile specific impact on FMD. 19 healthy controls (21.42 +/- 2.46 years) and 9 obese subjects (27 +/- 5.43 years old) participated in this study. Each subject performed two 5 min RH-FMD tests, two HGEX-FMD tests, and one 15 min RH-FMD test. BA diameter and blood velocity (BV) were assessed using ultrasound. Data are means ± SD. No differences in mean SS experienced during HGEX were observed between groups (p>0.05). %HGEX-FMD was significantly higher in the controls (11.34 ± 4.72% vs. 5.19 ± 3.00%)(p<0.001), while no differences in 5 min or 15 min RH-FMD were observed in the full study sample (p>0.05). To account for higher SS area under the curve (SS AUC) experienced by the obese group in both the 5 min RH- (p=0.055) and 15 min RH-FMD tests (p=0.004)...

Characterizing the function of the Fps/Fes tyrosine kinase in the mammary gland

Truesdell, Peter Francis
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 4049203 bytes; application/pdf
EN; EN
Relevância na Pesquisa
85.26%
The fps proto-oncogene encodes a 92 kDa cytoplasmic tyrosine kinase. Previous studies have shown that Fps expression in the mammary gland changes with development, and Fps has a suppressor function in mammary tumorigenesis. The aim of my thesis was to elucidate the role of the Fps tyrosine kinase in regulating mammary gland development and function. We have shown that the expression of the Fps kinase in the mammary gland increased during pregnancy and reached its maximum during lactation. The level of Fps tyrosine phosphorylation paralleled the expression pattern. Pups reared by fps-null females gained weight more slowly than those reared by wild-type females. Epithelial cells were the primary source of Fps expression. Milk protein and fat content were not affected by the absence of Fps. Similarly, no differences in mammary gland structure were observed with whole mount or histological analysis. Fps was shown to be in a multi-protein complex with E-cadherin, β-catenin and p120-catenin. A strong co-localization signal was observed for Fps and E-cadherin. Immunofluorescence analysis indicated that the localization of E-cadherin and β-catenin was disorganized and less concentrated at sites of cell-cell contacts in the fps-null glands. The interactions between the different adherens junction components were altered in the fps-null tissue. Specifically...

Investigating the contribution of the basal ganglia in the selective gating of saccade initiation

Gore, Joanna Lea
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1684999 bytes; application/pdf
EN; EN
Relevância na Pesquisa
75.24%
An important function of the brain is to inhibit irrelevant behaviors. This thesis examines the role of the basal ganglia in response suppression using saccadic eye movements as a model of behavior. We measured the activity of single saccade-related neurons in primate Substantia Nigra pars reticulata (SNr), a main output structure of the basal ganglia, while the context surrounding the initiation and suppression of saccades was manipulated. Inserting a temporal gap of no stimuli between the disappearance of a central visual fixation point and the appearance of a peripheral visual target leads to a reduction in saccadic reaction times (SRT); the ‘gap’ effect. SNr pause neurons decreased their activity during the gap and this decrease correlated with SRT. This finding suggests the SNr may contribute directly to producing the gap effect and that signals related to the effect are propagating through a frontal-basal ganglia circuitry to impact pre-saccade processing. Interleaving pro-saccade (look towards a visual stimulus) and anti-saccade (look away from visual stimulus) trials allowed us to investigate how neural processes change when preparing to suppress a saccade instead of making one automatically. We show that SNr neurons exhibit activity consistent with both suppression of automatic responses and facilitation of voluntary responses...

THE PHYSIOLOGICAL ACTIONS OF ADIPONECTIN IN CENTRAL AUTONOMIC NUCLEI: IMPLICATIONS FOR THE INTEGRATIVE CONTROL OF ENERGY HOMEOSTASIS

HOYDA, TED
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
75.22%
Adiponectin regulates feeding behavior, energy expenditure and autonomic function through the activation of two receptors present in nuclei throughout the central nervous system, however much remains unknown about the mechanisms mediating these effects. Here I investigate the actions of adiponectin in autonomic centers of the hypothalamus (the paraventricular nucleus) and brainstem (the nucleus of the solitary tract) through examining molecular, electrical, hormonal and physiological consequences of peptidergic signalling. RT-PCR and in situ hybridization experiments demonstrate the presence of AdipoR1 and AdipoR2 mRNA in the paraventricular nucleus. Investigation of the electrical consequences following receptor activation in the paraventricular nucleus indicates that magnocellular-oxytocin cells are homogeneously inhibited while magnocellular-vasopressin neurons display mixed responses. Single cell RT-PCR analysis shows oxytocin neurons express both receptors while vasopressin neurons express either both receptors or one receptor. Co-expressing oxytocin and vasopressin neurons express neither receptor and are not affected by adiponectin. Median eminence projecting corticotropin releasing hormone neurons, brainstem projecting oxytocin neurons...

Large-Eddy Simulations of Plane and Radial Wall-Jets over Smooth and Rough Surfaces

Banyassady, Rayhaneh
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
85.21%
Large-eddy simulations were carried out to investigate the flow dynamics of wall jets over smooth and rough surfaces. Results were validated against data in the literature. A sand-grain roughness model is used, based on an immersed boundary method. To understand the extent to which the outer/inner layer modifies the inner/outer layer and the extent to which the effect of roughness spreads away from the wall, instantaneous and mean flow fields were investigated. For the Reynolds numbers and roughness heights considered in this study, the effect of roughness is mostly confined to the near-wall region in both plane and radial configurations. There is no structural difference between the outer layer over smooth and rough surfaces. Roughness does not affect either the size of the outer-layer structures or the scaling of the profiles of Reynolds stresses in the outer layer. However, in the inner layer, roughness redistributes stresses from streamwise to wall-normal and spanwise directions. Contours of joint probability-density function of the streamwise and wall-normal velocity fluctuations at the bottom of the logarithmic region match those of the turbulent boundary layer at the same height; traces of the outer-layer structures were detected at the top of the logarithmic region...

Evaluating the Role of the Herpes Simplex Virus Type 2 UL21 Protein in Early and Late Events of the Viral Replication Cycle

Alter, JAKE
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
75.25%
The herpes simplex virus type 2 (HSV-2) UL21 protein is conserved between all members of the Alphaherpesvirinae subfamily. Although UL21 is essential for virus propagation in HSV-2, its function in viral replication is poorly understood. Cells infected with HSV-2 strains lacking UL21 exhibit an approximate two-hour delay in viral gene expression that cannot be explained by a defect in virus entry or capsid engagement with, or movement along, microtubules. However, we noted a defect in the ability of UL21 knockout (KO21) capsids to associate with the nucleus after infection. We found that the delay in viral gene expression was not directly due to the absence of UL21 insofar as cells stably expressing UL21 could not complement the delay in gene expression. We suggest that the KO21 delay in gene expression is due to alterations in virion composition and that in the absence of UL21, a key virion component required for the timely delivery of capsids to the nucleus fails to be packaged into virions. Interestingly, at late times after infection, levels of viral proteins in KO21 infected cells reach wild-type levels, indicating that a secondary function is responsible for the essential nature of UL21. We found that at late times post-infection KO21 infected cells accumulated capsids in the nucleus but these fail to reach the cytoplasm and mature into infectious virions. Thus...

HYDROGEN SULFIDES ACTIONS IN THE PARAVENTRICULAR NUCLEUS OF THE HYPOTHALAMUS

Khademullah, CHARLINE SAHARA
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
85.24%
Hydrogen sulfide (H2S) is a novel neurotransmitter that has been shown to influence cardiovascular function as well as other autonomic and endocrine functions by targeting a wide range of ion channels. Using whole-cell electrophysiology, I have investigated the potential role of H2S in the regulation of neuronal excitability in the paraventricular nucleus of the hypothalamus (PVN), which is a central relay centre for autonomic and endocrine function. In current-clamp recordings, sodium hydrosulfide hydrate (NaHS), when perfused onto PVN slices at various concentrations (0.1, 1, 10, and 50 mM), elicited a concentration-dependent response relationship from the majority of recorded neurons, with almost exclusively depolarizing effects. Input resistance differences from baseline, and during the NaHS-induced depolarization, uncovered a biphasic response, implicating both a potassium (K+) and non-selective cation conductance. In order to further investigate H2Ss effects on K+ conductances, we used both voltage- and current-clamp techniques to examine the effects of NaHS at either 1 or 10 mM on both the transient and sustained voltage-activated K+ currents in these neurons. We applied TEA+ (10 mM) to isolate the transient/rapidly inactivating current (IA) and 4-AP (5 mM) to isolate the sustained/delayed rectifier current (IK)...

Evidence Linking the Structure and Function of the Internal Pudendal Artery to Erectile Function: Impact of Aging, Hypertension, Antihypertensive Treatments and Lifestyle Modifications

Hannan, JOHANNA
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 6116823 bytes; application/pdf
EN; EN
Relevância na Pesquisa
85.27%
Erectile dysfunction and cardiovascular disease share etiologies, and commonly coexist. One unifying concept is that the arterial insufficiency in hypertension is also the primary basis for blunted sexual responses. The objective of these studies was to characterize the age-related changes in the structure and function of the pudendal artery (the main resistance vessel) in young and old normotensive and hypertensive animals in relation to erectile function. In addition, we assessed the impact of antihypertensive treatments and lifestyle modifications, such as exercise and/or caloric restriction, on erectile responses and the structure and function of the pudendal artery. In 30 week old hypertensive rats or following re-challenges at 50 and 70 weeks, antihypertensive treatment (enalapril or hydralazine) did not prevent the age-related decline in erectile function. Experiments involving cross-over kidney transplantations between treated and untreated young hypertensive rats revealed that changes in penile vasculature and not the level of arterial pressure were important for normalizing erectile responses. In addition, intervention with exercise and caloric restriction showed that these treatments substantially improved erectile responses in normotensive and hypertensive rats. The pudendal artery in young normotensive rats was found to have a thick medial layer but a relatively small lumen. With age...

Responses of zooplankton community structure and ecosystem function to the invasion of an invertebrate predator, Bythotrephes longimanus

Strecker, Angela Lee
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1841060 bytes; application/pdf
EN; EN_US
Relevância na Pesquisa
75.25%
Freshwater ecosystems face unprecedented levels of human-induced stresses and it is expected that the invasion of non-indigenous species will cause the greatest loss of biodiversity in lakes and rivers worldwide. Bythotrephes longimanus is a predatory invertebrate that invaded North America in the early 1980s, first being detected in the Great Lakes, and then moving to a number of inland lakes in Ontario and the northern United States. Using experimental and survey-based approaches, I tested several hypotheses concerning the effects of Bythotrephes on native zooplankton community structure and function. My results indicate that Bythotrephes reduces total abundance, biomass, and richness of zooplankton, especially cladoceran taxa, throughout the ice-free season. As a result of high predation pressure by the invader, total seasonal and epilimnetic zooplankton production was also substantially reduced in invaded lakes, which may have important consequences for the transfer of energy to fish and other taxa that feed on zooplankton. Interestingly, there was some evidence that zooplankton shifted their reproduction in time and space to avoid Bythotrephes, which may buffer the effects of the invader on food web functioning. Other measures of ecosystem function were relatively unaffected by the invasion of Bythotrephes. In addition...

Estimating glottal voicing source characteristics by measuring and modeling the acceleration of the skin on the neck

Cheyne, Harold Arthur, 1971-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 202 p.; 19511603 bytes; 19511357 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
75.22%
In the clinical management of voice patients, quantifying vocal function is becoming increasingly important both for corroborating clinicians' subjective impressions during a voice evaluation and for assessing the effectiveness of surgery or voice therapy. Current devices for quantifying vocal function measure acoustic, aerodynamic or electric signals (i.e., sound pressure, airflow, or electroglottography) during short tasks such as reading. One technique that has shown potential for measuring vocal function but has been mostly used to quantify speech-related behaviors besides phonation is measuring the acceleration of the skin near the larynx. The acceleration of the skin on the neck between the cricoid cartilage and the sternal notch arises from the airflow pulses that result from vocal-fold vibration. At least two sets of structures play a role in transforming these airflow pulses into the measured acceleration: the subglottal system, and the tissues between the subglottal airspace and the accelerometer (e.g., tracheal cartilage, skin, etc.). Advantages of measuring acceleration over current techniques include 1) the structures that filter the glottal pulses vary less over time than the vocal tract and thus they may be adequately modeled as time-invariant...

Role of the lateral olivocochlear efferent system in hearing : selective lesioning studies; Role of LOC efferent system in hearing : selective lesioning studies

Darrow, Keith N. (Keith Noble)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 68 leaves
ENG
Relevância na Pesquisa
85.19%
Sensory cells and afferent auditory neurons in the cochlea receive efferent feedback via olivocochlear (OC) neurons originating in the brainstem's olivary complex. The OC system comprises 1) medial (M)OC neurons that decrease electromotility in outer hair cells, and 2) lateral (L)OC neurons that elicit slow excitation or inhibition of auditory nerve dendrites that contact inner hair cells. We investigated the organization and function of the LOC system by immunohistochemical and physiological studies in mice with unilateral stereotaxic destruction of LOC cell bodies. Double immunostaining in control cochleas and brainstems revealed two cytochemical subgroups of LOC neurons: a majority cholinergic population and a minority dopaminergic population. The observation of two LOC subgroups is consistent with reports that LOC activation can either excite or inhibit auditory nerve activity. In lesioned mice, we observed two physiological abnormalities. First, ipsilateral ears were more vulnerable to noise-induced auditory nerve dysfunction, consistent with speculation that dopaminergic transmission controls glutamate excitotoxicity of auditory nerve dendrites after acoustic overexposure.; (cont.) Second, ipsilateral auditory nerve responses were increased while contralateral responses were decreased...

¿Es posible una política universitaria en materia de compromiso social? La experiencia del grupo de compromiso social de la Universidad de Cantabria; Is it possible a university policy about social commitment? Experience at the University of Cantabria with the social commitment group.

Cacho Sánchez, Yaelle; Llano Martínez, Lucía
Fonte: Asociación Universitaria de Formación del Profesorado Publicador: Asociación Universitaria de Formación del Profesorado
Tipo: info:eu-repo/semantics/article; publishedVersion
SPA
Relevância na Pesquisa
95.2%
RESUMEN: El grupo de compromiso social de la Universidad de Cantabria quiere proponer una nueva política universitaria, hasta ahora inexistente, en materia de compromiso social. Para ello, este grupo, a través de subgrupos de trabajo mixtos y multidisciplinares (alumnado, PAS y PDI), utiliza una metodología de trabajo participativa de abajo hacia arriba. Los resultados iniciales de este proceso muestran el papel clave que tiene el PAS en el proceso y un claro desconocimiento interno de las políticas universitarias propias. Asimismo, aún sin estrategia desarrollada, algunos miembros del grupo han comenzado a desplegar iniciativas de compromiso desde sus áreas.; ABSTRACT: Social Commitment Group of the University of Cantabria wants to propose a new university policy hitherto nonexistent in social commitment. For this, the Group, through mixed and multidisciplinary subgroups (students, PAS and PDI), uses a participatory and bottom-up methodology. The initial results of this process are the key role of the PAS in the process and a clear disregard for our own internal university policies. Although the strategy is not developed yet, some members have begun deploying engagement initiatives from their areas.