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How newly appointed chief information officers take charge : exploring the dynamics of leader socializationGerth, Anthony B. 06 1900 (has links)
The transition for any executive into a new appointment is a challenge. This transition for the newly appointed Chief Information Officer (CIO) is especially challenging given the complexity and ambiguous nature of their role. Investment in information technology (IT) has steadily increased over the past twenty years and contributes to enabling business changes that drive organizational performance improvements. The role of the Chief Information Officer (CIO) has evolved into an executive who holds significant responsibility for leading the organization in realizing these investment benefits. Therefore unsuccessful CIO transitions can negatively impact the extent to which the organization’s IT benefits are fully realized.
This research has one objective: to increase our understanding of the process of taking charge for the newly appointed Chief Information Officer (CIO). This increased understanding contributes to academic research as well as provides insights to practicing CIOs that will increase their probability of successfully taking charge of a new appointment.
The project explores this phenomenon in depth from both the CIO’s and non-IT executive’s (CxO) perspective through semi-structured interviews with 43 executives. Participants included twenty-one Chief Information Officers and twenty-two C-suite, non-IT executives.
The study integrates concepts from role theory and leader socialization with CIO leadership challenges. Findings indicate that the newly appointed CIO experiences a mutual adjustment process when they take charge. This adjustment occurs within their role set; the IT leadership team, the Chief Executive Officer (CEO) and the other top management team members (CxOs).
The data suggests that CIOs experience three overlapping phases of taking charge; Entry, Stabilization and Renewal. These phases result in confidence, credibility and legitimacy as a new leader in the organization. The data further reveals that the type of transition (Start-up, Turnaround, Realignment or Success-sustaining) encountered by the CIO is a significant influence on the taking charge process.
CIO socialization is influenced heavily by their role set and the expectations within it. CIOs will encounter CxO peers with varying preferences on interaction style and focus. In addition the CxOs in the study identified three different views of CIOs that reinforce the role ambiguity for the newly appointed CIO.
The study reveals that CIOs experience organizational socialization in two domains of leadership. These domains are supply-side and demand-side leadership. The data suggests that supply-side socialization occurs prior to demand-side socialization. These socialization outcomes are dependent on transition type.
This research extends previous work done on CIO transitions by identifying phases, activities and outcomes. An additional contribution is the first empirical model of new CIO socialization. Leader socialization research is enhanced with the study of a non-CEO executive. This model contributes a deeper understanding of the mutual adjustment process experienced by a newly appointed CIO.
Practicing CIOs can apply these findings in developing transition plans and actions for taking a new appointment. The CxO types and attitudes can inform the newly appointed CIO on customizing their relationship building approaches. Understanding that taking charge requires 2-3 years can lead to more realistic expectations of the executive. The findings of this study can lead CIOs to a higher probability of success in taking charge of a new appointment.
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AFL-CIO foreign policy : an Algerian example, 1954-1962France, Judith E. January 1981 (has links)
The AFL-CIO established and maintained a foreign affairs organization, independent of the U.S. State Department, between the years 1954 and 1962. It engaged in foreign affairs activities as a means to protect itself and its ideology from domestic and foreign interference, to maintain or enhance domestic power and to satisfy its leaders' interests. What were the union's foreign policy commitments? Why were these chosen and by whom? How were these policies implemented? How effective was the union in fulfilling its commitments?The purpose of this paper is to answer these questions using the AFLCIO's activities in support of the Algerian independence movement, 19541962, as the primary example. Algeria was chosen because American labor actions on behalf of Algerian independence clearly demonstrated labor's principal foreign policy, commitment, viz. anti-Communism, and illustrated two of the main components of this basic policy: ending colonialism and gaining allies for the West.The Algerian example demonstrated the lengths to which labor would go in its struggle against Communism. Algeria was not a colony but an integral part of France, much like Alaska is of the United States. However, because the AFL-CIO leaders feared Communist infiltration of Algeria, they refused to recognize Algeria's legal status and supported its secession from France.In support of independence, American labor used the full range of its foreign policy options, including direct assistance to Algerian trade States to urge France to surrender Algeria. Labor's pursuit of its policies in and for Algeria did not go smoothly. The U.S. continued to supportunionists and indirect assistance to the revolution by pressuring the United France. The French were unrelenting in their opposition to labor's activities. The Algerian nationalists refused to compromise their conditions for accepting direct aid from American labor. Even after Algeria achieved independence, American labor could not be sure it had accomplished its goals. Algeria outlawed the Communist Party but it also refused alignment with the West and muzzled its trade union. American labor had difficulty implementing its policies in Algeria because most American labor leaders held unrealistic expectations regarding the role of labor in independent Algeria.Since it is necessary to document the existence of a separate labor foreign policy organization, an historical sketch is included in this paper. Further, to understand the circumstances surrounding the Algerian independence movement which affect labor's and the U.S. State Department's attitudes and activities, it is useful to know the nature of the relationships among Algeria, France and the U.S. Another historical sketch accomplishes this.The paper demonstratesthat the AFL-CIO (between 1954 and 1962) maintained an independent foreign affairs organization which established and pursued foreign policies. These policies were determined by the AFLCIO leadership and were primarily directed toward combatting Communism by developing free democratic trade union(s). The Algerian example will show that the implementation of union policies yielded inconclusive results due to circumstances largely beyond the union's control, viz. Algeria's determination to become an unaligned nation and its unwillingness to permit its trade union to become a source of potential political and economic opposition.
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Working for change young reformers in labor unions and public schools /Rooks, Anne MacPherson, January 2007 (has links)
Thesis (Ph. D.)--UCLA, 2007. / Vita. Includes bibliographical references (leaves 206-218).
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Walter P. Reuther and the United Auto Workers' decision to intervene in the Power Reactor Development Company controversy, 1956-1961Woo, Robert Ken. January 1989 (has links)
Thesis (A.B., Honors)--Harvard University, 1989. / Includes bibliographical references.
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Efeito de uma sess?o de exerc?cio intervalado de alta intensidade e exerc?cio cont?nuo de moderada intensidade sobre marcadores de apetite em homens com obesidadeMatos, Victor Ara?jo Ferreira 10 July 2017 (has links)
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Previous issue date: 2017-07-10 / Introdu??o: O exerc?cio f?sico ? considerado uma estrat?gia fundamental no tratamento da obesidade por promover aumento no d?ficit cal?rico. Evid?ncias recentes sugerem que o exerc?cio de alta intensidade pode induzir altera??es fisiol?gicas que diminuem o apetite, contribuindo para redu??o da ingest?o cal?rica, fen?meno conhecido como anorexia induzida pelo exerc?cio (AIE). Objetivo: comparar o efeito agudo do exerc?cio intervalado de alta intensidade (EIAI) e exerc?cio cont?nuo de intensidade moderada (ECMI) sobre o consumo energ?tico e percep??o do apetite em homens com obesidade. M?todos: A pesquisa caracterizou-se como um ensaio cl?nico randomizado com delineamento cruzado. Quinze volunt?rios (31,0 ? 6,1 anos, 31,0 ? 6,0 kg/m?, 40,1 ? 2,2% de gordura corporal) foram submetidos a tr?s sess?es experimentais, separadas por sete dias: I) EIAI (10 x 1 min a 90% da frequ?ncia card?aca m?xima [FCm?x] + 1 min recupera??o ativa), II) ECMI (20 min a 70% da FCm?x) e III) Controle (sem exerc?cio). Uma refei??o padronizada foi oferecida 60 min antes de cada sess?o. A percep??o subjetiva do apetite (fome, saciedade, plenitude e perspectiva de consumo alimentar) foi avaliada por meio de uma escala visual anal?gica (EVA) em tr?s momentos: 1) pr?-sess?o, 2) p?s-sess?o e 3) uma hora ap?s sess?o. O consumo alimentar ad libitum foi analisado uma hora ap?s as sess?es experimentais e controle, por meio de registro pesado e o consumo alimentar ao longo do dia da sess?o (24 h) foi avaliado por meio de um registro alimentar estimado. A ANOVA two-way com medidas repetidas foi utilizada para analisar poss?veis diferen?as entre as condi??es e momentos na percep??o do apetite e uma ANOVA de medidas repetidas para analisar as diferen?as entre as condi??es no consumo alimentar ad libitum e 24 h. Resultados: N?o houve diferen?as significativas na percep??o de fome [F(1,3, 17,5)=0,00, p=0,972], saciedade [F(1,3, 17,5)=0,00, p=0,972], plenitude [F(2, 28)=0,13, p=0,876] e perspectiva de consumo [F(2, 28)=0,76, p=0,476] entre as condi??es, bem como n?o foram identificadas diferen?as significativas no consumo energ?tico na refei??o ad libitum: CON (674,5 ? 252,1), ECMI (666,7? 213,8) e EIAI (689,6? 263,8kcal) [F (2, 28)=0,13, p=0,877] e ao longo do dia da sess?o: CON (2857,6 ? 867,2), ECMI (2608,5? 595) e EIAI (2556,1? 489,5kcal) [F (2, 28) = 1,54, p=0,233]. Conclus?o: Uma sess?o de EIAI e ECMI n?o modificou o apetite e o consumo energ?tico ap?s 60 min e ao longo do dia em homens com obesidade. / Introduction: Physical exercise is considered a fundamental strategy in the treatment of obesity by promoting increase in the caloric deficit. Recent evidence suggests that high-intensity exercise can induce physiological changes that suppress appetite, decreasing caloric intake, a phenomenon known as exercise-induced anorexia (EIA). Objective: compare the acute effect of high intensity interval exercise (HIIE) and continuous moderate intensity exercise (ECM) on energy intake and appetite perception in obese men. Methods: The study was characterized as a randomized clinical trial in cross-over design. Fifteen volunteers (31.0 ? 6.1 years, 31.0 ? 6.0 kg/ m?, 40.1 ? 2.2% body fat) underwent three experimental sessions, seven days apart: I) HIIE ( 10x 1 min at 90% of maximal heart rate [HRmax] + 1 min active recovery), II) ECM (20min to 70% of HRmax) and III) Control (without exercise). A standardized meal was offered 60 min before each session. Appetite perception (hunger, satiety, fullness and perspective food consumption) were evaluated through a visual analogue scale (VAS) in three moments: 1) Pre-session, 2) Post-session and 3) one hour after session. Energy intake was assessed one hour after session with an ad libitum meal and the consumption throughout the day (24hrs) was analyzed with a estimated food record. ANOVA Two-way with repeated measures was used to analyze the differences between conditions and moments on appetite perception and ANOVA with repeated measures to assess the differences between conditions on energy intake in ad libitum and 24hrs. Results: There were no significant differences on hunger [F (1.3, 17.5) = 0.00, p = 0.972], satiety [F (1.3, 17.5) = 0.00, p = 0.972], fullness [F (2, 28) = 0.13, p = 0.876] and prospective food consumption [F (2, 28) = 0.76, p = 0.476] between conditions. As well as no significant differences on energy intake were observed during ad libitum meal: CON (674,5 ? 252,1), ECM (666,7? 213,8) e HIIE (689,6? 263,8kcal) [F (2, 28) = 0.13, p = 0.877] and throughout the day CON (2857,6 ? 867,2), ECM (2608,5? 595) e HIIE (2556,1? 489,5kcal) [F (2, 28) = 1.54, p = 0.233].Conclusion: A single session of HIIE and ECM did not modified appetite and energy intake 60 min after and during the day following exercise in obese man.
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Efeito do treinamento concorrente no controle auton?mico card?aco, desempenho cardiorrespirat?rio, for?a muscular e na composi??o corporal de pessoas vivendo com HIV/AIDSAndrade, Ricardo Dias de 26 February 2016 (has links)
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Previous issue date: 2016-02-26 / Introdu??o: O controle da infec??o pelo HIV atrav?s da TARV, acarretou em diversos efeitos adversos as pessoas vivendo com HIV/Aids (PVHA), como as s?ndromes lipodistr?fica e de wasting. O treinamento f?sico tem sido indicado como forma de retard?-los ou ameniz?-los, os estudos com treinamento f?sico para PVHA t?m mostrado efeitos positivos sobre o controle auton?mico card?aco, composi??o corporal, for?a muscular e na capacidade cardiorrespirat?ria. M?todos: Sete PVHA, do sexo masculino, sob uso da TARV, foram submetidas a uma interven??o com treinamento concorrente durante 18 semanas. O treinamento resistido teve caracter?stica de periodiza??o ondulat?ria, e o treinamento aer?bio prescrito em intensidade leve e de forma linear. O controle auton?mico card?aco foi avaliado pela variabilidade da frequ?ncia card?aca atrav?s dos dom?nios da frequ?ncia (HF, LF e a raz?o LF/HF). Foi aplicado o teste de caminhada de seis minutos para a avalia??o da capacidade cardiorrespirat?ria e do desempenho neuromuscular. Para a avalia??o da for?a muscular foi utilizado o m?todo da tonelagem absoluta, calculada a cada microciclo e mesociclo. As vari?veis antropom?tricas foram analisadas por segmento corporal, sendo obtidas a massa gorda total, do tronco e dos membros superiores e inferiores, al?m da massa corporal e IMC.A an?lise estat?stica foi realizada atrav?s do c?lculo do tamanho do efeito (d de Cohen), exceto para a an?lise da tonelagem absoluta, que foi analisada atrav?s do teste ANOVA one-way, com post hoc de scheffe. Resultados: Foram encontrados tamanhos de efeito alto (d>0,80) para a an?lise da variabilidade da frequ?ncia card?aca para as vari?veis LF e HF, mas n?o para a raz?o LF/HF, ap?s 18 semanas. Tamb?m foram encontrados efeitos moderados (d>0,50) ou fracos (d>0,20) para a composi??o corporal e no desempenho cardiorrespirat?rio. Al?m de diferen?as significativas para a for?a muscular a partir do 4? mesociclo. Conclus?o: O treinamento concorrente induziu efeitos positivos no controle auton?mico card?aco, na composi??o corporal, no desempenho cardiorrespirat?rio e na for?a muscular, assim, a prescri??o de treinamentos com varia??es de cargas, como aplicado neste estudo, deve ser indicado como forma de interven??o n?o medicamentosa para PVHA. / The control of HIV infection by HAART, brought a many of adverse effects to people living with HIV/Aids (PLHA), as a lipodystrophy and wasting syndromes. The physical training has been indicated as means to delay or soften then, the studies with physical training to PLHA have been showed positive effects on cardiac autonomic control, body composition, muscular strength and cardiorespiratory fitness. Seven PLHA, male and under HAART use, Underwent a concurrent training protocol during 18 weeks. The resistance training has an ondulatory periodization, and the aerobic training was conducted in low intensity and linear model. The cardiac autonomic control was evaluated by heart rate variability, through frequency domains (LF, HF and LF/HF ratio). Was applied the six minute walking test evaluate the cardiorespiratory fitness and neuromuscular performance. For the muscular strength evaluation was used the absolute tonnage method, calculated for each microcycle and mesocycle. The anthropometric variables were analyzed for each body segment, being get the total fat mass, trunk and the upper and lower limbs, further body mass and BMI. The statistical analyze was conducted by effect size formula (Cohen?s d), except the absolute tonnage, that was analyzed by ANOVA one-way test, with scheffe post hoc. Were found high effect sizes (d<0,80) to analyze the heart rate variability to the LF and HF variables, but not to LF/HF ratio, after 18 weeks. Also were found moderate (d>0,50) and lower (d>0,20) effect size to body composition and cardiorespiratory fitness. Further the significant difference in muscular strength since fourth mesocycle. The concurrent training induced positive effects on cardiac autonomic control, body composition, cardiorespiratory fitness and the muscular strength, so, the training prescription with load variations, as applied in this study, have be indicated as non-medicine intervention to PLHA.
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Jogo digital como ferramenta facilitadora no exerc?cio da matem?tica fundamentalSilva, ?lvaro Hermano da 25 April 2016 (has links)
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Previous issue date: 2016-04-25 / Para alunos que ingressam no primeiro ano de um curso t?cnico integrado, a matem?tica ? uma das disciplinas de dif?cil entendimento. Fatores como falta de aten??o, problemas com interpreta??o de texto e problemas no aprendizado no ensino fundamental, colaboram com as reprova??es na disciplina, gerando um aumento no desest?mulo do aluno no curso. Com base em relatos dos professores da disciplina de matem?tica feitos ao setor pedag?gico da escola sobre as dificuldades desses alunos em resolver as atividades trabalhadas em sala de aula e ap?s a realiza??o de entrevistas com um grupo de alunos, os referidos fatores de dificuldade foram identificados e poss?veis solu??es foram tra?adas. Uma delas ? a implementa??o de um jogo digital, a ser trabalhado no ambiente escolar, que proporcione o exerc?cio da matem?tica fundamental, como forma de trabalhar aspectos cognitivos e o conhecimento dos conte?dos da disciplina, gerando dados sobre o desempenho do jogador, proporcionando um feedback ao professor sobre dificuldades e/ou facilidades na resolu??o das quest?es. Este trabalho apresenta a proposta de jogo concebida. / For students who start their first High School year in a technical
integrated course, Mathematics is a hard understanding subject. Based
on teachers? reports to the pedagogical office stating the difficulties from
students to resolve activities explained in class and after interviewing a
group of students, this work identified reasons such as lack of
attention/focus, difficulties on reading the texts and understanding the
studied background, troubles on basic mathematical operations from
elementary school. Thus, possible solutions were outlined. One option is
the implementation of a digital game to be worked at school. This game
provides the exercising of fundamental mathematical operations in a way
to enhance cognitive aspects and the knowledge about the contents of the
subject. It eventually provides a teacher?s feedback about the difficulties
or facilities to resolve the questions the game presents. This work
presents the proposal of the conceived game.
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Recurso videocirúrgico para estudos de inseminação artificial transcervical em ovinos /Taira, Augusto Ryonosuke January 2018 (has links)
Orientador: Wilter Ricardo Russiano Vicente / Resumo: RESUMO - O objetivo deste trabalho foi desenvolver um recurso videocirúrgico para inseminação artificial (IA) transcervical em ovinos. Foram utilizadas 30 ovelhas da raça Santa Inês com idades entre 2 a 5 anos todas pluríparas, divididas em três grupos experimentais: 1) IA por técnica convencional com tração cervical (GC); 2) IA por vídeo-vaginoscopia com insuflação (GVS) e; 3) IA videoassistida com fixação cervical (GVF). Durante o procedimento foi registrado o tipo do óstio cervical, número de anéis transpassados, local de deposição do sêmen no trato reprodutivo, tempo de manipulação cervical, taxa de passagem e fibrinogênio plasmáticos como marcador de reação inflamatória entre as técnicas. O diagnóstico gestacional foi realizado 21 dias após a inseminação artificial. Todos os dados foram submetidos a teste de normalidade seguido de um pós-teste, utilizando o programa estatístico R versão 3.2.5. Para o GVF a técnica não permitiu a entrada ao interior do útero com o aparelho, devido a ausência de expansão cervical associado à presença de muco no canal cervical, dificultaram a visualização. A insuflação da cavidade vaginal do GVS possibilitou a visualização da entrada do óstio cervical com facilidade, com a deposição do sêmen no interior do útero sem a fixação cervical em 10% dos animais (1/10). O número de anéis transpassados diferiu de acordo com o grupo experimental. Para o tempo de procedimento o GVF apresentou maior tempo de manipulação, quando comparado com os demais g... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
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Rela??o entre hipertens?o arterial sist?mica e efici?ncia da troca de calor durante a recupera??o ao exerc?cio f?sico realizado em ambiente quenteFonseca, Sueli Ferreira da 21 February 2014 (has links)
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Previous issue date: 2014 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / A hipertens?o arterial sist?mica essencial parece estar associada com hipertonia simp?tica dependente da atividade colin?rgica central. Dessa forma, hipertensos poderiam apresentar respostas de dissipa??o de calor aprimoradas, especialmente durante a recupera??o do exerc?cio f?sico moderado realizado sob condi??o de estresse t?rmico. Diante disso, o objetivo do estudo foi avaliar as respostas termorregulat?rias de sujeitos hipertensos durante e na recupera??o de exerc?cio f?sico de intensidade moderada realizado em ambiente quente. Para tanto, oito hipertensos essenciais (H) e oito normotensos (N) (idade: 46,5?1,3 e 45,6?1,4 anos; ?ndice de massa corporal: 25,8?0,8 e 25,6?0,6 kg/m2; press?o arterial m?dia: 98,0?2,8 e 86,0?2,3 mmHg, respectivamente) permaneceram na c?mara ambiental (38?C e 60% umidade relativa do ar) durante 2h e 30 minutos (30 minutos em repouso, 1h de exerc?cio na esteira (50% VO2pico) e 1h em recupera??o do exerc?cio). Temperaturas da pele e corporal interna, frequ?ncia card?aca e press?o arterial foram mensuradas. C?lculos de produ??o de calor, taxa de ac?mulo de calor, temperatura corporal, troca de calor por radia??o, convec??o, e atrav?s do trato respirat?rio e suor evaporado foram realizados a partir das vari?veis coletadas. Como resultados, a press?o arterial m?dia dos hipertensos foi maior do que dos normotensos durante todo o protocolo experimental (p < 0,05). Apesar dos par?metros termorregulat?rios avaliados n?o terem sido diferentes entre grupos hipertensos e normotensos em repouso e durante o exerc?cio f?sico no calor, os hipertensos apresentaram menor quantidade de calor acumulado (H: -24,23 ? 3,39 W/m?, N: -13,63 ? 2,24 W/m?, p = 0,03), maior varia??o na temperatura corporal (H: -0,62 ? 0,05 ?C, N: -0,35? 0,12 ?C, p = 0,03) e maior quantidade de suor evaporado (H: -106,1 ? 4,59 W/m?, N: -91,15 ? 3,24 W/m?, p = 0,01) no per?odo de recupera??o p?s-exerc?cio. Al?m disso, a quantidade de suor evaporado relacionou-se com calor acumulado (r = 0,82, p < 0,001) e com a varia??o da temperatura corporal durante a recupera??o p?s-exerc?cio f?sico (r = 0,82, p < 0,001). Concluindo, indiv?duos hipertensos essenciais, em uso dos medicamentos iECA e diur?ticos, apresentam dissipa??o de calor acumulado aprimorada, por meio da evapora??o do suor e, consequentemente, maior resfriamento corporal durante a recupera??o de exerc?cio f?sico de intensidade moderado em ambiente quente. Methods: A total of 8 essential hypertensive (H) and 8 normotensive participants (N) (age: 46.5 ? 1.3 and 45.6 ? 1.4 years, BMI: 25.8 ? 0.8 and 25.6 ? 0.6 kg/m2, mean arterial pressure: 98.0 ? 2.8 and 86.0 ? 2.3 mmHg, respectively) remained in the environmental chamber (38 ?C and 60 % relative humidity) for 2 hours and 30 minutes (30 min at rest, 1 h of treadmill exercise at 50 % of VO2max and 1 h at rest during recovery exercise). Skin and core temperatures, heart rate and blood pressure were measured. Calculations of heat production, heat storage, mean body temperature, heat exchange by radiation, convection and evaporated sweat were performed from the collected variables.
Results: The mean blood pressure of the hypertensive subjects was higher than of the normotensive participants throughout the experimental protocol (p < 0.05). Although the thermoregulatory parameters evaluated did not differ between groups at rest and during exercise, the hypertensive subjects had lower amounts of heat storage (H: -24.23 ? 3.39 W/m?, N: -13.63 ? 2,2.4 W/m?, p = 0.03), greater variations in body temperature (H: -0.62 ? 0.05 ?C, N: -0.35? 0.12 ?C, p = 0.03), and a greater amount of evaporated sweat (H: -106.1 ? 4.59 W/m?, N: -91.15 ? 3.24 W/m?, p = 0.01) during the recovery period. Furthermore, the amount of evaporated sweat correlated with heat storage (r = -0.82; p < 0.001) and with the variation in mean body temperature during the recovery period (r = -0.82; p < 0.001).
Conclusion: Essential hypertensive participants present with improved sweat evaporation and greater heat dissipation and body cooling during recovery from moderate-intensity exercise performed in the heat. / Disserta??o (Mestrado) ? Programa Multic?ntrico de P?s-gradua??o em Ci?ncias Fisiol?gicas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014. / ABSTRACT
Purpose: The systemic arterial hypertension is associated with sympathetic hypertonia dependent on central cholinergic activity. Thus, it is believed that hypertensive individuals have an enhanced response of heat dissipation, especially during recovery from moderate-intensity exercise performed under heat stress conditions. Thus, the aim of this study was to examine the thermoregulatory responses of hypertensive subjects during and after (recovery period) moderate-intensity exercise performed in the heat.
Methods: A total of 8 essential hypertensive (H) and 8 normotensive participants (N) (age: 46.5 ? 1.3 and 45.6 ? 1.4 years, BMI: 25.8 ? 0.8 and 25.6 ? 0.6 kg/m2, mean arterial pressure: 98.0 ? 2.8 and 86.0 ? 2.3 mmHg, respectively) remained in the environmental chamber (38 ?C and 60 % relative humidity) for 2 hours and 30 minutes (30 min at rest, 1 h of treadmill exercise at 50 % of VO2max and 1 h at rest during recovery exercise). Skin and core temperatures, heart rate and blood pressure were measured. Calculations of heat production, heat storage, mean body temperature, heat exchange by radiation, convection and evaporated sweat were performed from the collected variables.
Results: The mean blood pressure of the hypertensive subjects was higher than of the normotensive participants throughout the experimental protocol (p < 0.05). Although the thermoregulatory parameters evaluated did not differ between groups at rest and during exercise, the hypertensive subjects had lower amounts of heat storage (H: -24.23 ? 3.39 W/m?, N: -13.63 ? 2,2.4 W/m?, p = 0.03), greater variations in body temperature (H: -0.62 ? 0.05 ?C, N: -0.35? 0.12 ?C, p = 0.03), and a greater amount of evaporated sweat (H: -106.1 ? 4.59 W/m?, N: -91.15 ? 3.24 W/m?, p = 0.01) during the recovery period. Furthermore, the amount of evaporated sweat correlated with heat storage (r = -0.82; p < 0.001) and with the variation in mean body temperature during the recovery period (r = -0.82; p < 0.001).
Conclusion: Essential hypertensive participants present with improved sweat evaporation and greater heat dissipation and body cooling during recovery from moderate-intensity exercise performed in the heat.
Methods: A total of 8 essential hypertensive (H) and 8 normotensive participants (N) (age: 46.5 ? 1.3 and 45.6 ? 1.4 years, BMI: 25.8 ? 0.8 and 25.6 ? 0.6 kg/m2, mean arterial pressure: 98.0 ? 2.8 and 86.0 ? 2.3 mmHg, respectively) remained in the environmental chamber (38 ?C and 60 % relative humidity) for 2 hours and 30 minutes (30 min at rest, 1 h of treadmill exercise at 50 % of VO2max and 1 h at rest during recovery exercise). Skin and core temperatures, heart rate and blood pressure were measured. Calculations of heat production, heat storage, mean body temperature, heat exchange by radiation, convection and evaporated sweat were performed from the collected variables.
Results: The mean blood pressure of the hypertensive subjects was higher than of the normotensive participants throughout the experimental protocol (p < 0.05). Although the thermoregulatory parameters evaluated did not differ between groups at rest and during exercise, the hypertensive subjects had lower amounts of heat storage (H: -24.23 ? 3.39 W/m?, N: -13.63 ? 2,2.4 W/m?, p = 0.03), greater variations in body temperature (H: -0.62 ? 0.05 ?C, N: -0.35? 0.12 ?C, p = 0.03), and a greater amount of evaporated sweat (H: -106.1 ? 4.59 W/m?, N: -91.15 ? 3.24 W/m?, p = 0.01) during the recovery period. Furthermore, the amount of evaporated sweat correlated with heat storage (r = -0.82; p < 0.001) and with the variation in mean body temperature during the recovery period (r = -0.82; p < 0.001).
Conclusion: Essential hypertensive participants present with improved sweat evaporation and greater heat dissipation and body cooling during recovery from moderate-intensity exercise performed in the heat.
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Participa??o do sistema colin?rgico central na modula??o das respostas cardiovasculares e termorregulat?rias em ratos espontaneamente hipertensosFonseca, Sueli Ferreira da 15 December 2017 (has links)
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Previous issue date: 2017 / Existem evid?ncias que a estimula??o colin?rgica central aumenta a dissipa??o de calor em
ratos normotensos como consequ?ncia de altera??es cardiovasculares via modula??o da
atividade barorreflexa. No entanto, n?o h? dados publicados sobre o envolvimento do sistema
colin?rgico central nestas respostas em modelo experimental que apresenta altera??o da
sensibilidade dos barorreceptores e d?ficit termorregulat?rio. Assim, o objetivo do presente
estudo foi verificar o envolvimento do sistema colin?rgico central na modula??o das repostas
cardiovasculares e termorregulat?rias durante o repouso e exerc?cio f?sico em ratos
espontaneamente hipertensos (SHR). Ratos Wistar machos (n = 33) e SHR (n = 33) foram
implantados com uma c?nula intracerebroventricular (icv) para inje??es de 2 ?L de
fisostigmina (fis) ou solu??o salina (sal). Temperaturas da cauda (Tcauda) e corporal interna
(Tint), press?o arterial sist?lica (PAS), frequ?ncia card?aca (FC) e taxa metab?lica foram
registradas durante os 60 minutos em que os ratos permaneceram em repouso, bem como
durante o exerc?cio f?sico at? a fadiga ap?s inje??es icv randomizadas. Na situa??o repouso, o
tratamento com fis iniciou uma sucess?o de respostas cardiovasculares e termorregulat?rias
que resultaram em aumento da PAS, redu??o da FC e aumento de Tcauda nos grupos Wistar e
SHR. A magnitude da ativa??o desses mecanismos foi mais intensa no SHR, afetando a Tint e
melhorando a dissipa??o de calor. Durante o exerc?cio f?sico, o tratamento com fis foi capaz
de modular as repostas cardiovasculares promovendo aumento significativo da PAS, seguido
de bradicardia reflexa em ratos SHR e Wistar. Estas respostas foram mais intensas nos ratos
Wistar. N?o houve diferen?a significativa para a Tcauda e Tint no grupo SHR fis em rela??o ao
grupo sal. Entretanto, fis impactou positivamente no desempenho f?sico. Em conjunto, esses
resultados fornecem evid?ncias que, durante a situa??o de repouso, a estimula??o colin?rgica
central modula as repostas termorregulat?rias por meio de mudan?as no sistema
cardiovascular de ratos Wistar e SHR, sendo que essas respostas s?o mais acentuadas em ratos
SHR impactando na dissipa??o de calor. Durante o exerc?cio f?sico, a administra??o central de
fis promove altera??es no sistema cardiovascular de ratos normotensos e hipertensos. Apesar
dessas altera??es n?o terem sido suficientes para ajustar as respostas termorregulat?rias em
ratos SHR, impactaram positivamente no desempenho f?sico. / Tese (Doutorado) ? Programa Multic?ntrico de P?s-Gradua??o em Ci?ncias Fisiol?gicas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / There is evidence that central cholinergic stimulation increases heat dissipation in
normotensive rats through changes on the cardiovascular system via modulation of
baroreceptors function. However, there is no published data regarding the involvement of the
central cholinergic system in cardiovascular and thermoregulatory responses in spontaneously
hypertensive rats (SHR), which are animals that possess altered baroreceptor sensitivity and
thermoregulatory deficit. Therefore, the aim of this study was to verify the involvement of the
central cholinergic system in cardiovascular and thermoregulatory adjustments in SHR. Male
Wistar (n = 33) and SHR (n = 33) rats were implanted with an intracerebroventricular (icv)
cannula for injections of 2 ?L of physostigmine (phy) or saline (sal) solution. Tail (Ttail) and
internal body temperatures (Tint), systolic arterial pressure (SAP), heart rate (HR) and
metabolic rate were registered during 60 minutes while the animals remained at rest and
during exercise until fatigue after randomly receiving the injections. Phy treatment started a
succession of cardiovascular and thermoregulatory responses that resulted in increased SAP,
reduced HR and increased Ttail in both Wistar and SHR groups. The magnitude of the
activation of these mechanisms seems to be more intense in SHR, even affecting the Tint, and
improve heat dissipation. During physical exercise, the phy treatment was able to modulate
the cardiovascular responses promoting a significant increase of SAP, followed by reflex
bradycardia in SHR and Wistar rats. These responses were more intense in Wistar rats. There
was no significant difference for Ttail and Tint in the SHR group, however, phy positively
impacted the physical performance. Taken together, these results provide evidence that at rest
the central cholinergic stimulation modulates thermoregulatory responses through changes in
the cardiovascular system of Wistar and SHR rats, and SHR rats presented greater
cardiovascular and thermoregulatory responses than normotensive rats after central
cholinergic stimulation. During physical exercise the central administration of phy promotes
adjustments in the cardiovascular system of normotensive and hypertensive rats. Although
these adjustments were not sufficient to pair the thermoregulatory responses in SHR rats, they
had a positive impact on physical performance.
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