<p>Two types of mesoscale wind-speed jet and their effects on boundary-layer structure were studied. The first is a coastal jet off the northern California coast, and the second is a katabatic jet over Vatnajökull, Iceland. Coastal regions are highly populated, and studies of coastal meteorology are of general interest for environmental protection, fishing industry, and for air and sea transportation. Not so many people live in direct contact with glaciers but properties of katabatic flows are important for understanding glacier response to climatic changes. Hence, the two jets can potentially influence a vast number of people.</p><p>Flow response to terrain forcing, transient behavior in time and space, and adherence to simplified theoretical models were examined. The turbulence structure in these stably stratified boundary layers was also investigated. Numerical modeling is the main tool in this thesis; observations are used primarily to ensure a realistic model behavior.</p><p>Simple shallow-water theory provides a useful framework for analyzing high-velocity flows along mountainous coastlines, but for an unexpected reason. Waves are trapped in the inversion by the curvature of the wind-speed profile, rather than by an infinite stability in the inversion separating two neutral layers, as assumed in the theory. In the absence of blocking terrain, observations of steady-state supercritical flows are not likely, due to the diurnal variation of flow criticality.</p><p>In many simplified models, non-local processes are neglected. In the flows studied here, we showed that this is not always a valid approximation. Discrepancies between simulated katabatic flow and that predicted by an analytical model are hypothesized to be due to non-local effects, such as surface inhomogeneity and slope geometry, neglected in the theory. On a different scale, a reason for variations in the shape of local similarity scaling functions between studies is suggested to be differences in non-local contributions to the velocity variance budgets.</p>

Graduation date: 1999

Two types of mesoscale wind-speed jet and their effects on boundary-layer structure were studied. The first is a coastal jet off the northern California coast, and the second is a katabatic jet over Vatnajökull, Iceland. Coastal regions are highly populated, and studies of coastal meteorology are of general interest for environmental protection, fishing industry, and for air and sea transportation. Not so many people live in direct contact with glaciers but properties of katabatic flows are important for understanding glacier response to climatic changes. Hence, the two jets can potentially influence a vast number of people. Flow response to terrain forcing, transient behavior in time and space, and adherence to simplified theoretical models were examined. The turbulence structure in these stably stratified boundary layers was also investigated. Numerical modeling is the main tool in this thesis; observations are used primarily to ensure a realistic model behavior. Simple shallow-water theory provides a useful framework for analyzing high-velocity flows along mountainous coastlines, but for an unexpected reason. Waves are trapped in the inversion by the curvature of the wind-speed profile, rather than by an infinite stability in the inversion separating two neutral layers, as assumed in the theory. In the absence of blocking terrain, observations of steady-state supercritical flows are not likely, due to the diurnal variation of flow criticality. In many simplified models, non-local processes are neglected. In the flows studied here, we showed that this is not always a valid approximation. Discrepancies between simulated katabatic flow and that predicted by an analytical model are hypothesized to be due to non-local effects, such as surface inhomogeneity and slope geometry, neglected in the theory. On a different scale, a reason for variations in the shape of local similarity scaling functions between studies is suggested to be differences in non-local contributions to the velocity variance budgets.

A growing body of literature suggests that higher levels of physical activity and cardiorespiratory fitness, as well as an alternative treatment such as low level laser therapy (LLLT), have beneficial effects on cognition, while sedentary lifestyle-induced obesity and vascular risk negatively influence cognition. However, the relationship between cardiorespiratory fitness and vascular risk on cognitive function and the effect of an acute bout of very vigorous aerobic exercise (acute exercise) on cognitive performance has not yet been investigated. Additionally, the effects of combined acute exercise and LLLT treatments on cognitive performance have not yet been characterized. Therefore, the goal of this dissertation was to conduct a series of three research studies ranging from a cross-sectional exploratory study about the association of cardiorespiratory fitness, obesity, and vascular risk on cognitive function, to an experimentally designed study that compared the effects of acute exercise, LLLT, and the combination of these two treatments on cognitive performance in young adults. Study1 examined the relationship among cardiorespiratory fitness (maximal oxygen consumption, VO2max), obesity indices (body mass index, BMI; waist circumstance), and vascular risk (C-reactive protein; CRP). Cognitive function included crystalized intelligence (Kaufman Brief Intelligence Test; KBIT), executive functions of inhibition (Stroop test), switching (Trail making test; TMT), attention (Psychomotor Vigilance Task; PVT), and working memory (Delayed-Match-to-Sample, DMS). Study 2 determined the effect of acute exercise on cognitive performance including executive response inhibition (Stroop test) and response switching (TMT) and brain-derived neurotrophic factor (BNDF). Study 3 compared the effectiveness of LLLT and acute exercise on cognitive performance, which included attention (PVT) and working memory (DMS). Results demonstrated there was a beneficial effect of physical exercise-induced improvements in cardiorespiratory fitness on vascular risk and cognitive functions particularly in working memory and inhibitory control (Study1). Acute exercise improved performance in inhibitory control and increased the BNDF level compared to the control condition, suggesting the acute exercise-induced the increase in BDNF level may be at least in part of mediating the cognitive performance improvement (Study 2). All three conditions (acute exercise, LLLT, or the combination) improved performance in attention and working memory, as measured by reaction time and response accuracy, when compared to a control group. Specially, the combined group showed a trend of greater improvement in attention and worming memory performance (Study 3). Taken together, the results of this research series suggest that acute exercise and LLLT can improve cognitive performance, which is also mediated by health indices including cardiorespiratory fitness, obesity, and vascular risk. It is anticipated that these findings will make substantive contributions to the empirical literature concerning the beneficial effect of exercise and LLLT on cognitive health in young adults, given the current paucity of research. / text

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It has been observed within the provincial department under study, that officials occupying levels 1-4 constituted approximately 70% of the population that participated in the National Public Service Strike of 2007. Higher level employees piggy-back on the efforts of low level employees, since they do not participate in industrial action, do not have any deductions made from their salaries due to the implementation of the 'no work no pay' rule, but derive benefits from the collective efforts of industrial action. This study explored the rationale for the participation of low level employees in industrial action in a Public Sector Provincial Department. The objectives of the study was to establish the psychological motivation for low level employees engaging in collective action and the types of behaviour low level employees engage in when participating in industrial action. In this study, the population constituted all level 1-4 employees that participated in the Public Service Strike of 2007. The sample included 80 subjects that were selected, using the probability simple random sampling design, from the population. The questionnaire was used as a data collection tool. Frequency distributions, percentages, chisquare distributions and graphs were used to analyse the data. Very strong response rates were received for subjects indicating that they did not participate in strike/protest action because they thought that they can have a holiday or that the supervisor will not be at work. Very strong response rates were also recorded for subjects indicating that they did not force/influence other people to participate in strike/protest action when they themselves participated in strike/protest action. Strong response rates were received for subjects indicating that they did not participate in strike/protest action because other employees of similar level as them participated in strike/protest action, they were not absent on the day of a strike/protest action because of the pressure from union officials or that they were forced by union officials not to attend work, that when they participated in strike/protest action they were notified by the union about the strike, that when they participated in strike/protest action they participated in union marches/rallies, that they participated in strike/protest action because their grievances were not attended to and that they participated in strike/protest action because they believed that they could control events by their own behaviour. Moderate response rates were recorded for subjects indicating that they participated in strike/protest because they felt that they were worse off than other employees who earn more and have greater benefits than they have, that they participated in strike/protest because they were frustrated and dissatisfied in the work place and that they participated in strike/protest action because they believed that such behaviour could impact on political processes. This study has provided greater insight into the rationale for the participation of low level employees in industrial action despite the monetary losses they suffer due to the implementation of the 'no work no pay' rule. / Thesis (M.Admin.)-University of KwaZulu-Natal, 2008.

Made available in DSpace on 2015-07-22T20:50:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-25 / O retalho cutâneo é um procedimento cirúrgico freqüente na cirurgia plástica, essencialmente nas perdas de substâncias, sendo fundamental na reconstrução funcional e estética de deformidades traumáticas, congênitas ou de origem neoplásica. A insuficiência arterial do retalho é a principal complicação que, se duradoura, pode levar à necrose. O laser de baixa intensidade tem merecido destaque por promover aumento da microcirculação, aceleração do processo cicatricial de feridas e neoformação vascular. Objetivo: Investigar a Potência do laser de baixa intensidade na viabilidade do retalho cutâneo randômico, em ratos. Métodos: Trinta e seis animais foram distribuídos aleatoriamente em grupo controle; grupo tratado com potência de 30mW e grupo tratado com potência de 60mW. Em ambos os grupos tratados foram utilizados a fluência de 3J/cm2. O retalho cutâneo foi realizado nos animais com uma barreira plástica interposta entre o retalho e o leito doador. A irradiação laser foi aplicada imediatamente após a operação e nos dias 1, 2, 3 e 4 após a operação. As porcentagens das áreas de necroses dos retalhos foram calculadas no 7º dia pós-operatório. Adicionalmente, 4 fragmentos de cada retalho foram coletados para calcular a densidade vascular segundo método bidimensional. Resultados: Os animais tratados mostraram a área de necrose estatisticamente menor do que o grupo controle (53 por cento). A necrose nos grupos tratados foi 24 por cento (grupo 30mW) e 25 por cento (grupo 60mW). Quanto à densidade vascular, os animais tratados demonstraram aumento estatisticamente significante em relação ao grupo controle (37 por cento), O grupo 30mW apresentou 57 por cento de densidade vascular e o grupo 60mW apresentou 59 por cento. Conclusão: O laser de baixa intensidade foi eficaz no aumento da viabilidade do retalho cutâneo randômico, não havendo diferenças entre as potências utilizadas / Background and Objectives: Potency values in low level laser therapy (LLLT) are not well defined. This present study was designed to assess the effects of LLLT with output power of 30 and 60mW, in the viability of a random skin flap in rats. Methods: Thirty six wistar rats were randomically divided in three groups: control (CG), was not irradiated; 30 mW potency (30mW) and 60 mW potency (60mW). In both treated groups a fluency of 3J/cm2 was used. Two minutes after elevation of a random pattern, cranially based, dorsal flap (4 x 10 cm), laser irradiation was applied and repeated on the first, second, third and fourth postoperative days. Percentages of flap necrosis were calculated on the seventh postoperative day. Also, four fragments of each flap were collected in order to allow determination of the percentages of vascular density, according to bidimensional method the blood vessels morphometric analysis. Statistical analysis included Wilcoxon’s test and Kruskal Wallis’ variance analysis. A significance level of 5 % was elected (p ≤ 0.005). Results: Laser treated animals presented significantly less necrosis than control rats (CG = 53 % x 30G = 24 %; p <0.05) (CG x 60G = 25 %; p < 0.05). No difference was found between laser treated animals. Also, laser treated animals presented significantly more vascular density than control rats (CG = 37 % x 30G = 57 %; p <0.05) (CG x 60G = 59 %; p < 0.05). No difference was found between laser treated animals. Conclusion: Low level laser with potency of 30 and 60mW, increased the viability of a random skin flap in rats. / TEDE / BV UNIFESP: Teses e dissertações

Made available in DSpace on 2014-10-09T12:28:56Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:37Z (GMT). No. of bitstreams: 1 17897.pdf: 1027757 bytes, checksum: d6b5ec3afbc6b4a705c60af963b604a7 (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP; Faculdade de Odontologia, Universidade de São Paulo, São Paulo

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A periodontite à uma doenÃa infecto-inflamatÃria crÃnica caracterizada por intensa perda Ãssea. P. granatum (PNG) e IrradiaÃÃo com Laser de Baixa Intensidade (ILBI) tÃm demonstrado propriedades anti-inflamatÃrias e antioxidantes. O objetivo deste estudo foi avaliar as atividades anti-inflamatÃria e antirreabsortiva Ãssea da PNG combinada ou nÃo com ILBI na periodontite induzida por ligadura em ratos. A periodontite foi induzida em 72 ratos Wistar atravÃs da inserÃÃo de um fio de nylon-3.0 em torno do segundo molar superior esquerdo. A hemimaxila contralateral foi utilizada como controle. Grupos de 6 animais receberam soluÃÃo salina 0,9% (SAL), SAL+ILBI 4 J/cm2, PNG (60, 180, 540) mg/kg ou combinaÃÃo de PNG 540 mg/kg+ILBI 4 J/cm2. O laser de baixa intensidade GaAlAs foi aplicado imediatamente apÃs a cirurgia, enquanto a PNG foi administrada, por gavagem, diariamente, atà o 11 dia, quando, entÃo, os animais foram mortos, suas maxilas removidas e processadas para anÃlises macroscÃpica, histomÃtrica, histolÃgica e marcaÃÃo imunohistoquÃmica para TRAP. Amostras de tecido gengival foram obtidas para avaliaÃÃo da atividade de mieloperoxidase (MPO). Foram coletadas amostras de sangue para dosagem dos nÃveis sÃricos de fosfatase alcalina Ãssea (FAO), leucograma e anÃlise das funÃÃes hepÃtica e renal. Adicionalmente, os Ãndices hepÃtico e renal foram realizados. Os ratos foram pesados diariamente. A induÃÃo da periodontite causou intensa perda Ãssea alveolar (POA), reduÃÃo sÃrica da FAO, destruiÃÃo do ligamento periodontal e do cemento, e intensa infiltraÃÃo leucocitÃria. Sistemicamente, a periodontite induziu leucocitose e nÃo causou alteraÃÃes nos nÃveis sÃricos de transaminases hepÃticas, ureia ou creatinina, bem como nos Ãndices hepÃtico e renal. A POA foi prevenida significantemente por PNG (60= 34%, 180= 34%, 540= 42%), SAL+ILBI= 31% e PNG 540+ILBI= 48% (p<0.05). PNG 540 combinada ou nÃo com ILBI preveniu a perda Ãssea alveolar, a infiltraÃÃo leucocitÃria e preservou o periodonto de maxilas nas quais a periodontite foi induzida. Animais tratados com PNG 540+ILBI mostraram significante reduÃÃo na imunomarcaÃÃo positiva para TRAP (Periodonto NÃo desafiado=0,0  0,0; SAL= 0,016  0,004; SAL+ILBI= 0,01  0,003; PNG 540= 0,011  0,003; PNG 540+ILBI= 0,002  0,0003). O aumento da atividade de MPO foi prevenido por PNG (60= 46%, 180= 49%, 540= 76%), SAL+ILBI= 54% e PNG 540+ILBI= 80% (p<0.05). Embora a reduÃÃo da FAO observada no grupo salina nÃo tenha sido prevenida por PNG ou SAL+ILBI (p>0,05), PNG 540+ILBI causou um aumento significante nos nÃveis sÃricos de FAO (74,2  5,4 U/l), quando comparado ao SAL (44,9  3,0 U/l) (p<0,05). Nenhum grupo apresentou mudanÃas significantes nos nÃveis sÃricos de transaminases hepÃticas, ureia ou creatinina ou nos respectivos Ãndices hepÃtico e renal (p>0,05), e todos os grupos preveniram (p<0,05) a leucocitose quando comparada ao grupo SAL. Em suma, PNG combinada ou nÃo com ILBI reduziu a infiltraÃÃo leucocitÃria e o nÃmero de neutrÃfilos alÃm de reduzir a perda Ãssea alveolar, à custa da inibiÃÃo da ativaÃÃo de osteoclastos, sem causar alteraÃÃes sistÃmicas importantes / Periodontitis is a chronic infectious inflammatory disease. P. granatum (PNG) and low level laser irradiation (LLLI) have demonstrated anti-inflammatory properties and antioxidants. The aim of this study was to evaluate the anti-inflammatory and bone antiresorptive activities of PNG combined or not with LLLI in ligature-induced periodontitis in rats. Periodontitis was induced in 72 rats by inserting a nylon-3.0 around the left upper second molar. The contralateral hemimaxila was used as control. Groups of 6 animals received saline 0.9% (SAL), SAL+LLLI 4 J/cm2, PNG [60, 180, 540 (mg/kg)] or PNG 540 mg/kg+LLLI 4 J/cm2. The low intensity laser GaAlAs was applied immediately after surgery, while PNG was administered by gavage daily until day 11, when the animals were killed. The jaws were removed and processed for macroscopic, histometric, histological and immunohistochemical staining for TRAP. Gingival tissue samples were obtained to evaluate the activity of myeloperoxidase (MPO). Blood samples were collected for measurement of serum bone alkaline phosphatase (BALP), leukograms and analysis of liver and kidney function. Additionally, indexes of liver and kidney were performed. Rats were weighted daily. Periodontitis induction caused intense alveolar bone loss (ABL), reduction of BALP, cementum and periodontal ligament destructions, and intense leukocyte infiltration. Systemically, periodontitis induced leukocytosis and and did not alter hepatic transaminases, urea or creatinine serum levels, or liver and kidney indexes. The ABL was prevented by PNG (60= 34%, 180= 34%, 540= 42%), SAL+LLLI= 31% e PNG 540+LLLI= 48% (p<0.05). PNG 540 combined or not with LLLI decreased the alveolar bone resorption, the leukocyte infiltration and preserved the periodontium in the jaws in which the periodontitis was induced. Animals treated with PNG 540+LLLI showed an important decreasing of TRAP positive immunostaining (Periodontium Unchallenged = 0.0  0.0, SAL= 0.016  0.004; SAL+LLLI= 0.01  0.003; PNG 540= 0.011  0.003; PNG 540+LLLI = 0.002  0.0003). The raise of MPO activity was prevented by PNG (60= 46%, 180= 49%, 540= 76%), SAL+LLLI= 54% e PNG 540+LLLI= 80% (p<0.05). In spite the reduction of BALP, seen in SAL group was not prevented by SAL+LLLI or PNG (p>0.05), the combined treatment with PNG 540+LLLI caused an increase on BALP serum levels (74.2  5.4 U/l), when compared to SAL (44.9  3.0 U/l) (p<0.05). No change was seen for hepatic transaminases, urea or creatinine serum levels, or in liver and kidney indexes, in all groups (p>0.05) and all groups prevented (p<0.05) the leukocytosis observed in SAL group. In short, PNG combined or not with LLLI reduced leukocyte infiltration and the number of neutrophils and reduced alveolar bone loss, at the expense of inhibiting osteoclast activation, without causing systemic changes

Made available in DSpace on 2014-10-09T12:28:56Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:37Z (GMT). No. of bitstreams: 1 17897.pdf: 1027757 bytes, checksum: d6b5ec3afbc6b4a705c60af963b604a7 (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP; Faculdade de Odontologia, Universidade de São Paulo, São Paulo