WorldWideScience

Sample records for calor transiente na

  1. Transferência de calor transiente na agitação linear intermitente de latas Transient heat transfer by intermittent shake of cans

    Directory of Open Access Journals (Sweden)

    Homero Ferracini Gumerato

    2007-09-01

    Full Text Available Foi estudada a transferência de calor transiente na agitação linear e intermitente (ALI de embalagens metálicas contendo simulantes de alimentos, objetivando-se sua aplicação em processos de pasteurização ou esterilização e conseqüentes tratamentos térmicos mais eficientes, homogêneos e com produto de melhor qualidade. Foram utilizados quatro meios fluidos simulantes de alimentos de diferentes viscosidades e massas específicas: três óleos e água. Foram combinados efeitos de cinco tratamentos, sendo: meio simulante (4 níveis, espaço livre (3 níveis, freqüência de agitação (4 níveis, amplitude de agitação (2 níveis e posição das latas (4 níveis. Os ensaios de aquecimento e resfriamento foram feitos em tanque com água à temperatura de 98 °C e 17-20 °C, respectivamente. Com os dados de penetração de calor em cada experimento, foram calculados os parâmetros de penetração de calor fh, jh, fc e jc. Os resultados foram modelados utilizando-se grupos de números adimensionais e expressos em termos de Nusselt, Prandtl, Reynolds e funções trigonométricas (com medidas de amplitude e freqüência de agitação, espaço livre e dimensões da embalagem. Foram estabelecidas as duas Equações gerais para as fases de aquecimento e resfriamento: Nu = ReA –0,199.Pr –0,288.sen(xa/AM0,406.cos(xf/FA–1,039.cos((xf/FA.(EL/H.p–4,556 Aquecimento Nu = 0,1295.ReA–0,047.Pr –0,193.sen(xa/AM0,114.cos(xf/FA–0,641.cos((xf/FA.(EL/H.p–2,476 Resfriamento O processo de ALI pode ser aplicado em pasteurizadores ou autoclaves estáticas horizontais e verticais, com modificações simples. Concluiu-se que a ALI aumenta significativamente a taxa de transferência de calor, tanto no aquecimento como no resfriamento.The transient heat transfer during the intermittent and linear shaking of tin plate cans containing simulating food was studied in order to apply this technology in the pasteurization and sterilization processes, achieving

  2. Métodos transientes de troca de calor na determinação das propriedades térmicas de materiais cerâmicos: II - o método do fio quente Thermal properties of ceramic materials by the non-steady techniques: II - the hot wire technique

    Directory of Open Access Journals (Sweden)

    W. N. dos Santos

    2005-12-01

    Full Text Available A condutividade térmica, a difusividade térmica e o calor específico, conhecidos como propriedades térmicas são as três propriedades físicas de um material mais importantes do ponto de vista de cálculos térmicos. Elas são essenciais na determinação dos parâmetros de resistência ao choque térmico em refratários e na determinação dos fatores de dissipação de calor em fornos e fornalhas. A condutividade térmica é um parâmetro importante em problemas envolvendo transferência de calor em regime estacionário, enquanto que a difusividade térmica é importante em estados não estacionários de troca de calor. O calor específico, propriedade importante em altas temperaturas, está associado ao consumo de energia durante o aquecimento. Normalmente essas três propriedades são determinadas separadamente por técnicas e equipamentos individuais. Hoje são conhecidos vários métodos para a determinação da condutividade térmica e difusividade térmica. Recentemente, os métodos transientes de troca de calor têm sido os métodos preferidos na determinação das propriedades térmicas de materiais. Neste trabalho é feita uma descrição e uma análise crítica de um dos métodos mais utilizados na determinação das propriedades térmicas de materiais cerâmicos: o método do fio quente. Com este método é possível determinar simultaneamente, a partir do mesmo transiente térmico experimental, as três propriedades térmicas. Resultados numéricos são também apresentados.Thermal conductivity, thermal diffusivity and specific heat, namely as the thermal properties, are the three most important physical properties of a material that are needed for heat transfer calculations. They are essential in thermal shock parameters determination or in calculations of heat dissipation factors in furnaces and kilns. Thermal conductivity is an important parameter in problems involving steady state heat transfer, while the thermal

  3. Spontaneous NA+ transients in individual mitochondria of intact astrocytes.

    Science.gov (United States)

    Azarias, Guillaume; Van de Ville, Dimitri; Unser, Michael; Chatton, Jean-Yves

    2008-02-01

    Mitochondria in intact cells maintain low Na(+) levels despite the large electrochemical gradient favoring cation influx into the matrix. In addition, they display individual spontaneous transient depolarizations. The authors report here that individual mitochondria in living astrocytes exhibit spontaneous increases in their Na(+) concentration (Na(mit)(+) spiking), as measured using the mitochondrial probe CoroNa Red. In a field of view with approximately 30 astrocytes, up to 1,400 transients per minute were typically detected under resting conditions. Na(mit)(+) spiking was also observed in neurons, but was scarce in two nonneural cell types tested. Astrocytic Na(mit)(+) spikes averaged 12.2 +/- 0.8 s in duration and 35.5 +/- 3.2 mM in amplitude and coincided with brief mitochondrial depolarizations; they were impaired by mitochondrial depolarization and ruthenium red pointing to the involvement of a cation uniporter. Na(mit)(+) spiking activity was significantly inhibited by mitochondrial Na(+)/H(+) exchanger inhibition and sensitive to cellular pH and Na(+) concentration. Ca(2+) played a permissive role on Na(mit)(+) spiking activity. Finally, the authors present evidence suggesting that Na(mit)(+) spiking frequency was correlated with cellular ATP levels. This study shows that, under physiological conditions, individual mitochondria in living astrocytes exhibit fast Na(+) exchange across their inner membrane, which reveals a new form of highly dynamic and localized functional regulation.

  4. Influência do aporte de calor e da velocidade de soldagem na tenacidade da solda HF-ERW

    OpenAIRE

    2012-01-01

    O processo de soldagem por resistência elétrica de alta frequência (High Frequecy Electric Resistance Welding, HF-ERW) apresenta três tipos de fenômenos de soldagem. Quando os fenômenos tipo 1 ou tipo 3 são os predominantes no processo de soldagem, a retenção de óxidos na junta soldada é facilitada e a melhor qualidade da junta soldada é obtida quando o fenômeno tipo 2 é o predominante. Dentre os parâmetros de soldagem, o aporte de calor e a velocidade têm grande influência na determinação de...

  5. APLICAÇÃO DO MÉTODO DE BALANÇO DE CALOR NA DETERMINAÇÃO DA TRANSPIRAÇÃO DE MUDAS DE LIMOEIRO

    Directory of Open Access Journals (Sweden)

    J.E. TREJO-CHANDIA

    1997-09-01

    Full Text Available O método de balanço de calor é usado para monitorar fluxo de seiva em plantas de diversas espécies. Neste trabalho, estudou-se o desempenho e aplicabilidade do método, em mudas de limoeiro com diâmetros em torno de 18 mm. Os sensores foram avaliados em plantas envasadas, em casa de vegetação, sob condições naturais de temperatura e radiação solar. O desempenho do método foi avaliado comparando-se o fluxo de massa computado e as medidas gravimétricas de perda de massa, fazendo-se depois, análise de regressão. Os resultados indicam que os sensores tiveram uma precisão de 8% na escala horária e 11% na escala diária. A constante de tempo foi de 12 minutos, o que é um indicativo de que o método é adequado para medir fluxo de seiva em mudas de citros com boa precisão, e suficientemente apropriado para ser usado em aplicações agronômicas e fisiológicas.The heat balance method is widely used to measure sap flow of different plant species. This work focused on the performance and applicability of the method, using 2-year old lemon plants, with 18 mm in diameter, the sensors were evaluated on potted-plants in a greenhouse under natural temperature and solar radiation conditions. The method performance was tested by comparing the computed mass flow with weight losses. A regression equation was used to analyse the data collected. The results showed that sensor precision reached 8% in the hourly scale and 11% in the daily scale. The time constant of 12 minutes indicated that the method was accurate to measure sap flow with good precision. Also we concluded that the method is adequate for agronomic and physiological use.

  6. Dose effects of oxaliplatin on persistent and transient Na+ conductances and the development of neurotoxicity.

    Directory of Open Access Journals (Sweden)

    Susanna B Park

    Full Text Available BACKGROUND: Oxaliplatin, a platinum-based chemotherapy utilised in the treatment of colorectal cancer, produces two forms of neurotoxicity--acute sensorimotor neuropathic symptoms and a dose-limiting chronic sensory neuropathy. Given that a Na(+ channelopathy has been proposed as the mechanism underlying acute oxaliplatin-induced neuropathy, the present study aimed to determine specific mechanisms of Na(+ channel dysfunction. METHODOLOGY/PRINCIPAL FINDINGS: Specifically the function of transient and persistent Na(+ currents were followed during treatment and were investigated in relation to oxaliplatin dose level. Eighteen patients were assessed before and after a single oxaliplatin infusion with motor and sensory axonal excitability studies performed on the median nerve at the wrist. While refractoriness (associated with Na(+ channel inactivation was significantly altered post-oxaliplatin infusion in both motor (Pre: 31.7±6.4%; Post: 68.8±14.5%; P≤.001 and sensory axons (Pre: 31.4±5.4%; Post: 21.4±5.5%; P<.05, strength-duration time constant (marker of persistent Na(+ conductances was not significantly altered post-infusion (Motor Pre: 0.395±0.01 ms; Post: 0.394±0.02 ms; NS; Sensory Pre:0.544±0.03 ms; Post: 0.535±0.05 ms; NS. However, changes in strength-duration time constant were significantly correlated with changes in refractoriness in motor and sensory axons (Motor correlation coefficient = -.65; P<.05; Sensory correlation coefficient = .67; P<.05. CONCLUSIONS/SIGNIFICANCE: It is concluded that the predominant effect of acute oxaliplatin exposure in human motor and sensory axons is mediated through changes in transient rather than persistent Na(+ conductances. These findings are likely to have implications for the design and trial of neuroprotective strategies.

  7. Níveis de cromo orgânico na dieta de codornas japonesas mantidas em estresse por calor na fase de postura Levels of organic chromium on diet of laying Japanese quails under heat stress

    Directory of Open Access Journals (Sweden)

    Marcelle Santana de Araújo

    2007-06-01

    Full Text Available O experimento foi conduzido com objetivo de avaliar o efeito da adição de cromo orgânico (Cr na alimentação de codornas japonesas na fase inicial de postura mantidas em estresse por calor. Seiscentas codornas com 63 dias de idade e peso inicial de 158,6 g foram mantidas em ambiente de alta temperatura (32ºC e alimentadas com dietas à base de milho e farelo de soja suplementadas com Cr (cromo-metionina em substituição ao inerte (0, 500, 1.000, 1.500 e 2.000 ppb. O delineamento utilizado foi o inteiramente casualizado, com cinco tratamentos, 12 repetições e dez aves por unidade experimental, adotando-se o teste de Willians a 5% de significância (a para análise de cada variável: produção de ovos (taxa de postura/ave/dia; taxa de postura por ave alojada; taxa de postura de ovos comercializáveis; peso de ovo; consumo de ração; conversão alimentar (por kg e por dúzia de ovos; e massa de ovos. O fornecimento de cromo orgânico no nível de 500 ppb promoveu melhora na produção de ovos comercializáveis e, no nível de 2.000 ppb, resultou em aumento no consumo de ração. As demais variáveis não foram influenciadas pelos níveis de Cr na dieta. O nível de 500 ppb de Cr na dieta é indicado para aumento da produção de ovos comercializáveis de codornas japonesas em fase de postura mantidas em estresse por calor.The objective was to evaluate the effects of the addition of organic chromium in the diet of Japanese quails in the initial fase of laying, under heat stress. Six hundred quails averaging 63 days old and initial body weight of 158.60 g on high temperature environment (32ºC were used. Diets were based on corn and soybean meal, and supplemented with five levels of chromium (0, 500, 1,000, 1,500, and 2,000 ppb, from chromium-methionine, in replacement with innert material. The experimental design was completely randomized, with 12 experimental units per treatment and ten birds in each experimental unit. The least

  8. Simulação da transferência de calor na articulação do joelho em modelo animal para condições de aquecimento e resfriamento

    OpenAIRE

    2011-01-01

    A aplicação terapêutica de calor e de frio é amplamente utilizada na prática clínica da fisioterapia, sendo especialmente relevante no tratamento de lesões do sistema musculoesquelético (osso, ligamento, músculo e tendão). Para que os benefícios decorrentes dessas terapias possam ser alcançados é necessário, entretanto, que o tecido alvo atinja uma faixa ótima de temperatura. Temperaturas fora da faixa terapêutica recomendada podem promover tratamentos ineficazes e até mesmo dano térmico ao t...

  9. Um planejamento de experimentos para a avaliação do fluxo de calor crítico de reatores nucleares a água pressurizada de pequena escala.

    OpenAIRE

    2014-01-01

    Um dos parâmetros termo-hidráulicos de segurança mais importantes no projeto e operação de reatores a água pressurizada é o fluxo de calor crítico (FCC). O FCC ocorre quando se atinge uma região de instabilidade na mudança de mecanismo de transferência de calor de uma parede aquecida para um fluido, aumentado drasticamente a temperatura da parede. Transientes em um reator nuclear podem afetar a taxa de geração de calor ou a fluxo de refrigerante no núcleo, prejudicando a retirada de calor das...

  10. Estudo do Fenômeno da Ilha de Calor na Cidade de Manaus/AM: Um Estudo a Partir de Dados de Sensoriamento Remoto, Modelagem e Estações Meteorológicas

    Directory of Open Access Journals (Sweden)

    Polari Batista Corrêa

    2016-06-01

    Full Text Available Resumo O fenômeno da ilha de calor (IC na cidade de Manaus foi estudado usando dados de modelagem do clima urbano com o modelo Weather Research and Forecasting (WRF e dados de estações meteorológicas. Foram usados os dados de temperatura da superfície (TS obtidos pelo sensor MODIS do satélite ambiental Aqua, produto MYD11A2 na resolução horizontal de 1 km por um 1 km para o período de 2002 a 2012 na cidade de Manaus para avaliar o processo de urbanização. Foi realizado um estudo de caso com as simulações de TS e de temperatura do ar (TA nos meses de agosto e setembro de 2009 que foram comparadas, respectivamente, com os dados de satélite e de estações meteorológicas. Identificou-se a distribuição espacial da TS na cidade, e as diferenças de TS entre a área urbana e a de floresta e entre a área urbana e de rios foram quantificadas. As diferenças de TS ao longo das faixas de longitude de 60,03° O a 59,97° O e de latitude de 3,09° S a −3,03° S foram analisadas com os dados do modelo WRF e do sensor MODIS. A intensidade da IC estimada com os dados de TA do modelo e de estações meteorológicas foram, em média, respectivamente de 1,87 °C e de 1,80 °C, consistentes com resultados anteriores. Portanto, a TA simulada pode ser usada para fins de estimar a intensidade da IC em Manaus.

  11. Calore e termodinamica

    CERN Document Server

    Zemansky, Mark W

    1970-01-01

    Temperatura ; sistemi termodinamici semplici ; lavoro ; il calore e il primo principio ; gas ideali ; teoria cinetica dei gas ideali ; il secondo principio della termodinamica ; reversibilità e temperatura Kelvin ; entropia ; meccanica statistica sostanze pure ; transizioni di fase, elio liquido ed elio solido ; sistemi particolari ; paramagnetismo, fisica delle basse temperature, temperature negative e terzo principio ; superfluidità e superconduttività ; equilibrio chimico ; reazioni con gas ideali ; sistemi eterogenei.

  12. FLUXOS DE CALOR E DIÓXIDO DE CARBONO ENTRE O OCEANO E A ATMOSFERA NA REGIÃO COSTEIRA E OCEÂNICA AO SUL DO BRASIL

    OpenAIRE

    Priscila Cavalheiro Farias

    2014-01-01

    O Oceano Atlântico Sudoeste é caracterizado, no inverno, pela presença de uma frente oceanográfica entre a Corrente do Brasil (CB) e a Corrente Costeira do Brasil (CCB). A frente oceanográfica CB/CCB gera intensos gradientes horizontais termais entre as águas frias da plataforma continental do Sul do Brasil, dominadas pela CCB, e águas quentes do oceano profundo, dominadas pela CB. Esse trabalho analisa, pela primeira vez na literatura conhecida, os mecanismos de acoplamento en...

  13. Analysis of conjugated heat transfer, in transient state of the first stage of a gas turbine; Analisis de transferencia de calor conjugada, en estado transitorio, de la primera etapa de una turbina de gas

    Energy Technology Data Exchange (ETDEWEB)

    Campos Amezcua, Alfonso; Mazur C, Zdzislaw [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Gallegos Munoz, Armando [Facultad de Ingenieria Mecanica, Electrica y Electronica (FIMEE), Universidad de Guanajuato, Guanajuato (Mexico)

    2007-11-15

    This article presents an analysis of conjugated heat transfer in the first stage of movable blades during the starting of a gas turbine, covering a period of 1,012 seconds. The developed computer model is in 3D and uses as initial and border conditions typical starting curves for stack gases, the cooling air and the angular velocity of the blades. As a result of the numerical predictions, the temperature distributions in stack gases, the trowel of the blade and the cooling air are included, doing emphasis in the results obtained in the solid (body of the blade), since these are used for thermo-mechanical stress analysis and later estimation of the blade residual life. [Spanish] Este articulo presenta un analisis de transferencia de calor conjugada en la primera etapa de alabes moviles, durante el arranque de una turbina de gas, cubriendo un periodo de 1.012 segundos. El modelo computacional desarrollado es en tres dimensiones y utiliza como condiciones iniciales y de frontera curvas de arranque tipicas para los gases de combustion, el aire de enfriamiento y la velocidad angular de los alabes. Como resultado de las predicciones numericas, se incluyen las distribuciones de temperatura en los gases de combustion, la paleta del alabe y el aire de enfriamiento, haciendo enfasis en los resultados obtenidos en el solido (cuerpo del alabe), ya que estos se utilizan para analisis de esfuerzos termomecanicos y posterior estimacion de vida residual del alabe.

  14. Achados à prova calórica e canal semicircular acometido na vertigem posicional paroxística benigna Caloric test results and damaged semicircular canal in benign positional paroxysmal vertigo

    Directory of Open Access Journals (Sweden)

    Andréa Manso

    2009-01-01

    Full Text Available OBJETIVO: Caracterizar os achados da prova calórica em pacientes com vertigem posicional paroxística benigna, segundo o canal semicircular comprometido. MÉTODOS: Foram analisados 1033 prontuários de pacientes submetidos à pesquisa de nistagmo posicional e de posicionamento e à eletronistagmografia. Os achados da prova calórica, de acordo com os canais semicirculares acometidos, foram submetidos à análise estatística. RESULTADOS: No comprometimento de canal posterior, houve prevalência de normorreflexia (pPURPOSE: To characterize caloric test results in benign paroxysmal positional vertigo patients, according to the damaged semicircular canal. METHODS: The data of 1033 patients submitted to Dix-Hallpike testing, positional nystagmus and electronystagmography were analyzed. Caloric test results were compared to the damaged semicircular canals and were submitted to statistical analysis. RESULTS: In cases with posterior canal damage, there was prevalence of normal responses compared to abnormal results (p<0.0001; hypo activity was more prevalent than hyperactivity (p<0.0001 and directional preponderance (p<0.0001, and hyperactivity more prevalent than directional preponderance (p<0.0001. In cases with lateral canal damage, normal responses were more prevalent than hypo activity (p<0.0001 and hyperactivity (p<0.0001; there was a tendency of prevalence of hypo activity over hyperactivity (p=0.0771, and directional preponderance was not observed. In cases with anterior canal damage, normal responses were more prevalent than hypo activity (p<0.0001; hyperactivity and directional preponderance were not observed. CONCLUSION: In the caloric test of benign positional paroxysmal vertigo patients, normal responses, hypo activity, hyperactivity or directional preponderance of post-caloric nystagmus occur in decreasing order of prevalence when the posterior canal is damaged; normal responses are more prevalent than hypoactive or hyperactive caloric

  15. Caloric Curves and Nuclear Expansion

    CERN Document Server

    Natowitz, J B; Ma, Y; Murray, M; Qin, L; Shlomo, S; Wada, R; Wang, J

    2002-01-01

    Nuclear caloric curves have been analyzed using an expanding Fermi gas hypothesis to extract average nuclear densities. In this approach the observed flattening of the caloric curves reflects progressively increasing expansion with increasing excitation energy. This expansion results in a corresponding decrease in the density and Fermi energy of the excited system. For nuclei of medium to heavy mass apparent densities $~0.3\\rho_0$ are reached at the higher excitation energies. The average densities derived in this manner are in good agreement with those derived using other, more complicated, techniques.

  16. Elementi di trasmissione del calore

    CERN Document Server

    Guglielmini, Giovanni

    1990-01-01

    Introduzione ; concetti fondamentali di conduzione termica ; conduzione termica in regime stazionario ; conduzione termica in regime variabile ; analisi numerica nei problemi do conduzione ; concetti fondamentali di convezione termica ; convezione forzata ; convezione naturale ; scambio termico in ebollizione e condensazione ; concetti fondamentali di radiazione termica ; scambio termico per radiazione ; scambiatori di calore ; problemi termici negli edifici.

  17. Sodium-23 magnetic resonance imaging during and after transient cerebral ischemia: multinuclear stroke protocols for double-tuned 23Na/1H resonator systems

    Science.gov (United States)

    Wetterling, Friedrich; Ansar, Saema; Handwerker, Eva

    2012-11-01

    A double-tuned 23Na/1H resonator system was developed to record multinuclear MR image data during and after transient cerebral ischemia. 1H-diffusion-, 1H perfusion, 1H T2-, 1H arterial blood flow- and 23Na spin density-weighted images were then acquired at three time points in a rodent stroke model: (I) during 90 min artery occlusion, (II) directly after arterial reperfusion and (III) one day after arterial reperfusion. Normal 23Na was detected in hypoperfused stroke tissue which exhibited a low 1H apparent diffusion coefficient (ADC) and no changes in 1H T2 relaxation time during transient ischemia, while 23Na increased and ADC values recovered to normal values directly after arterial reperfusion. For the first time, a similar imaging protocol was set-up on a clinical 3T MRI site in conjunction with a commercial double-tuned 1H/23Na birdcage resonator avoiding a time-consuming exchange of resonators or MRI systems. Multinuclear 23Na/1H MRI data sets were obtained from one stroke patient during both the acute and non-acute stroke phases with an aquisition time of 22 min. The lesion exhibiting low ADC was found to be larger compared to the lesion with high 23Na at 9 h after symptom onset. It is hoped that the presented pilot data demonstrate that fast multinuclear 23Na/1H MRI preclinical and clinical protocols can enable a better understanding of how temporal and regional MRI parameter changes link to pathophysiological variations in ischemic stroke tissue.

  18. Propriedades térmicas de polímeros por métodos transientes de troca de calor Thermal properties of polymers by non-steady state methods

    Directory of Open Access Journals (Sweden)

    Wilson N. dos Santos

    2003-12-01

    Full Text Available A determinação precisa das propriedades térmicas de um polímero é fundamental em muitos processos e projetos de engenharia. A difusividade térmica, em particular, é importante em problemas envolvendo estado não-estacionário, como no aquecimento e resfriamento de um polímero. Em processamento é uma propriedade fundamental no processo de moldagem por injeção, para a determinação do tempo de ciclo de moldagem. Neste trabalho, a técnica de pulso de energia, normalmente aplicada para materiais cerâmicos e metálicos, é empregada na determinação da difusividade térmica de materiais poliméricos. As amostras foram preparadas em forma de discos, tendo aproximadamente 1cm de diâmetro e 0,3 a 1mm de espessura. Os resultados experimentais obtidos foram comparados com dados existentes na literatura, e com aqueles obtidos pela técnica de fio quente. A concordância entre esses resultados e a reprodutibilidade das medidas mostrou a viabilidade da utilização desta técnica experimental para materiais poliméricos.The accurate determination of the thermal properties of a polymer is of fundamental importance in many processes and engineering projects. Specifically, the thermal diffusivity is an important property in the case of non-steady state problems, which occur during the heating and cooling of a polymer. In the extrusion process, the knowledge of the thermal properties is crucial in order to describe and analyse the extrusion process. In this work, the thermal diffusivity of some polymeric materials is determined by using the thermal diffusivity flash technique. The samples are prepared in the shape of discs, 1 cm in diameter and 0.3 to 1 mm thickness. The experimental results obtained are compared with those found in the literature. The reproducibility of the data is very good and they are in excellent agreement with the results obtained by the hot wire method.

  19. Effect of heat exposure on the thermoregulatory responses of selected naked neck chickens Efeito da exposição ao calor na resposta termorregulatória de aves de pescoço pelado selecionadas

    Directory of Open Access Journals (Sweden)

    C.M. Mazzi

    2002-02-01

    Full Text Available The variation in cloacal temperature, body weight loss and expression of the 70 kDa heat shock protein (Hsp70 in three naked neck broiler genotypes during heat stress were studied. Twelve birds of each genotype (Na/Na, Na/na and na/na were reared to market weight (approximately 2.1kg at thermoneutral temperature. Six birds from each group served as controls and the remaining six underwent gradual heat stress (from 28ºC to 36ºC. Cloacal temperature and body weight were measured before and after exposure to heat. Liver samples were collected and Hsp70 levels were quantified using western blotting with monoclonal anti-chicken Hsp70 antibody. Heterozygous (Na/na birds had a significantly lower cloacal temperature variation and less body weight loss during heat stress than the other genotypes. There was no significant difference in the Hsp70 levels among the genotypes. Heterozygous birds (Na/na appeared to have a slight advantage over the other genotypes during gradual heat stress, perhaps because of a heterotic effect.Estudaram-se o efeito do estresse térmico sobre a temperatura cloacal, a perda de peso corporal e a expressão da proteína de estresse de 70 kDa (Hsp70 em três genótipos de galinhas de pescoço-pelado. Foram usadas 12 aves de cada genótipo (Na/Na, Na/na e na/na, com peso corporal médio de 2,100kg e criadas em temperatura termoneutra. Seis aves de cada grupo serviram como controle e as seis restantes foram submetidas a estresse térmico gradativo (28ºC - 36ºC. A temperatura cloacal e o peso das aves foram avaliados antes e depois do estresse. Amostras de fígado foram coletadas e os níveis de Hsp70 foram quantificados por "western blotting" com anticorpo monoclonal específico para Hsp70 de galinha. As aves heterozigotas (Na/na tiveram variação de temperatura cloacal significativamente menor e menor perda de peso corporal durante o estresse térmico do que as dos outros genótipos. Não foi observada diferen

  20. Caloric Vestibular Stimulation as a Treatment for Conversion Disorder: A Case Report and Medical Hypothesis

    OpenAIRE

    Michael eNoll-Hussong; Sabrina eHolzapfel; Dan ePokorny; Simone D Herberger

    2014-01-01

    Conversion disorder is a medical condition in which a person has paralysis, blindness, or other neurological symptoms that cannot be clearly explained physiologically. To date, there is neither specific nor conclusive treatment. In this paper, we draw together a number of disparate pieces of knowledge to propose a novel intervention to provide transient alleviation for this condition. As caloric vestibular stimulation (CVS) has been demonstrated to modulate transiently a variety of cognitive ...

  1. Caloric restriction, caloric restriction mimetics, and healthy aging in Okinawa: controversies and clinical implications.

    Science.gov (United States)

    Willcox, Bradley J; Willcox, Donald C

    2014-01-01

    To examine the role of two nutritional factors implicated in the healthy aging of the Okinawans: caloric restriction; and traditional foods with potential caloric restriction-mimetic properties. Caloric restriction is a research priority for the US National Institute on Aging. However, little is known regarding health effects in humans. Some caloric restriction-related outcomes, such as cause-specific mortality and lifespan, are not practical for human clinical trials. Therefore, epidemiological data on older Okinawans, who experienced a caloric restriction-like diet for close to half their lives, are of special interest. The nutritional data support mild caloric restriction (10-15%) and high consumption of foods that may mimic the biological effects of caloric restriction, including sweet potatoes, marine-based carotenoid-rich foods, and turmeric. Phenotypic evidence is consistent with caloric restriction (including short stature, low body weight, and lean BMI), less age-related chronic disease (including cardiovascular diseases, cancer, and dementia), and longer lifespan (mean and maximum). Both caloric restriction and traditional Okinawan functional foods with caloric restriction-mimetic properties likely had roles in the extended healthspan and lifespan of the Okinawans. More research is needed on health consequences of caloric restriction and foods with caloric restriction-mimetic properties to identify possible nutritional interventions for healthy aging.

  2. Carnot to Clausius: Caloric to Entropy

    Science.gov (United States)

    Newburgh, Ronald

    2009-01-01

    This paper discusses how the Carnot engine led to the formulation of the second law of thermodynamics and entropy. The operation of the engine is analysed both in terms of heat as the caloric fluid and heat as a form of energy. A keystone of Carnot's thinking was the absolute conservation of caloric. Although the Carnot analysis was partly…

  3. Caloric curve of star clusters.

    Science.gov (United States)

    Casetti, Lapo; Nardini, Cesare

    2012-06-01

    Self-gravitating systems, such as globular clusters or elliptical galaxies, are the prototypes of many-body systems with long-range interactions, and should be the natural arena in which to test theoretical predictions on the statistical behavior of long-range-interacting systems. Systems of classical self-gravitating particles can be studied with the standard tools of equilibrium statistical mechanics, provided the potential is regularized at small length scales and the system is confined in a box. The confinement condition looks rather unphysical in general, so that it is natural to ask whether what we learn with these studies is relevant to real self-gravitating systems. In order to provide an answer to this question, we consider a basic, simple, yet effective model of globular clusters: the King model. This model describes a self-consistently confined system, without the need of any external box, but the stationary state is a nonthermal one. In particular, we consider the King model with a short-distance cutoff on the interactions, and we discuss how such a cutoff affects the caloric curve, i.e., the relation between temperature and energy. We find that the cutoff stabilizes a low-energy phase, which is absent in the King model without cutoff; the caloric curve of the model with cutoff turns out to be very similar to that of previously studied confined and regularized models, but for the absence of a high-energy gaslike phase. We briefly discuss the possible phenomenological as well as theoretical implications of these results.

  4. Caloric beverage consumption patterns in Mexican children

    Directory of Open Access Journals (Sweden)

    Rivera Juan A

    2010-10-01

    Full Text Available Abstract Background Mexico has seen a very steep increase in child obesity level. Little is known about caloric beverage intake in this country as well as all other countries outside a few high income countries. This study examines overall patterns and trends in all caloric beverages from two nationally representative surveys from Mexico. Methods The two nationally representative dietary intake surveys (1999 and 2006 from Mexico are used to study caloric beverage intake in 17, 215 children. The volume (ml and caloric energy (kcal contributed by all beverages consumed by the sample subjects were measured. Results are weighted to be nationally representative. Results The trends from the dietary intake surveys showed very large increases in caloric beverages among pre-school and school children. The contribution of whole milk and sugar-sweetened juices was an important finding. Mexican pre-school children consumed 27.8% of their energy from caloric beverages in 2006 and school children consumed 20.7% of their energy from caloric beverages during the same time. The three major categories of beverage intake are whole milk, fruit juice with various sugar and water combinations and carbonated and noncarbonated sugared-beverages. Conclusion The Mexican government, greatly concerned about obesity, has identified the large increase in caloric beverages from whole milk, juices and soft drinks as a key target and is initiating major changes to address this problem. They have already used the data to shift 20 million persons in their welfare and feeding programs from whole to 1.5% fat milk and in a year will shift to nonfat milk. They are using these data to revise school beverage policies and national regulations and taxation policies related to an array of less healthful caloric beverages.

  5. Effect of gravity on the caloric stimulation of the inner ear

    Science.gov (United States)

    Kassemi, Mohammad; Deserranno, Dimitri; Oas, John G.

    2004-01-01

    Robert Barany won the 1914 Nobel Prize in medicine for his convection hypothesis for caloric stimulation. Microgravity caloric tests aboard the 1983 SpaceLab 1 mission produced nystagmus results that contradicted the basic premise of Barany's convection theory. In this paper, we present a fluid structural analysis of the caloric stimulation of the lateral semicircular canal. Direct numerical simulations indicate that on earth, natural convection is the dominant mechanism for endolymphatic flow. However, in the microgravity environment of orbiting spacecraft, where buoyancy effects are mitigated, an expansive convection becomes the sole mechanism for producing endolymph motion and cupular displacement. Transient 1 g and microgravity case studies are presented to delineate the different dynamic behaviors of the 1 g and microgravity endolymphatic flows. The associated fluid-structural interactions are also analyzed based on the time evolution of cupular displacements.

  6. Na(+)/Ca(2+) exchanger 2 is neuroprotective by exporting Ca(2+) during a transient focal cerebral ischemia in the mouse.

    Science.gov (United States)

    Jeon, Daejong; Chu, Kon; Jung, Keun-Hwa; Kim, Manho; Yoon, Byung-Woo; Lee, C Justin; Oh, Uhtaek; Shin, Hee-Sup

    2008-05-01

    Na(+)/Ca(2+) exchanger (NCX), by mediating Na(+) and Ca(2+) fluxes bi-directionally, assumes a role in controlling the Ca(2+) homeostasis in the ischemic brain. It has been suggested that the three isoforms of NCX (NCX1, 2 and 3) may be differentially involved in permanent cerebral ischemia. However, the role of NCX2 has not been defined in ischemic reperfusion injury after a transient focal cerebral ischemia. Furthermore, it is not known whether NCX2 imports or exports intracellular Ca(2+) ([Ca(2+)](i)) following ischemia and reperfusion. To define the role of NCX2 in ischemia and reperfusion, we examined mice lacking NCX2, in vivo and in vitro. After an in vitro ischemia, a significantly slower recovery in population spike amplitudes, a sustained elevation of [Ca(2+)](i) and an increased membrane depolarization were developed in the NCX2-deficient hippocampus. Moreover, a transient focal cerebral ischemia in vivo produced a larger infarction and more cell death in the NCX2-deficient mouse brain. In particular, in the wild type brain, NCX2-expressing neurons were largely spared from cell death after ischemia. Our results suggest that NCX2 exports Ca(2+) in ischemia and thus protects neuronal cells from death by reducing [Ca(2+)](i) in the adult mouse brain.

  7. Merenje prelaznih opterećenja na dva modela u aero tunelu t-38 / Measurement of transient loads on two models

    Directory of Open Access Journals (Sweden)

    Aleksandar Vitić

    2008-07-01

    Full Text Available Pri ispitivanju modela u "rafalnom" aerotunelu sa prekidnim dejstvom T-38, na Mahovim brojevima većim od 2, moraju se uzeti u obzir prelazne pojave koje se javljaju na početku i na kraju rada aerotunela. To su stanja kada su model i aerovaga izloženi velikim aerodinamičkim silama i momentima. Ova kombinovana opterećenja mogu oštetiti modele i aerovage, pa bi bilo potrebno unapred znati kolike se vrednosti očekuju za pojedine konfiguracije modela, kako bi se izvršio pravilan izbor aerovage i odgovarajućih materijala za izradu modela. U tu svrhu postoje dijagrami koji pružaju mogućnost procene ovih opterećenja. Dijagrami su dobijeni na osnovu ispitivanja nekoliko različitih modela na Mahovim brojevima većim od 2. U radu su prikazana merenja prelaznih opterećenja na još dva modela, a rezultati su upoređeni sa već postojećim dijagramima. / The T-38 wind tunnel is a blow down, intermittent-run type of wind tunnels. During model testing in the this type of wind tunnels, at Mach numbers higher than 2, transient loads which appear during the starting and stopping of the wind tunnel runs must be taken into consideration. These are the conditions when a model and the wind tunnel balance are exposed to large aerodynamic forces and moments. These combined loads can damage models and wind tunnel balances, and, for this reason, it is very important to determine them in advance for any particular model configuration so that an appropriate wind tunnel balance and materials for model manufacturing can be chosen. For that purpose there are graphs which give possibilities to estimate these loads. The graphs are based on experiments with a number of different models at Mach numbers higher than 2. This paper gives the measurements of transient loads on two more models and the results are compared with the already existing graphs.

  8. Intake of calorically sweetened beverages and obesity

    DEFF Research Database (Denmark)

    Olsen, N J; Heitmann, B L

    2009-01-01

    The prevalence of obesity has increased in the past 30 years, and at the same time a steep increase in consumption of soft drinks has been seen. This paper reviews the literature for studies on associations between intake of calorically sweetened beverages and obesity, relative to adjustment...... studies were identified. The majority of the prospective studies found positive associations between intake of calorically sweetened beverages and obesity. Three experimental studies found positive effects of calorically sweetened beverages and subsequent changes in body fat. Two experimental studies did...... not find effects. Eight prospective studies adjusted for energy intake. Seven of these studies reported associations that were essentially similar before and after energy adjustment. In conclusion, a high intake of calorically sweetened beverages can be regarded as a determinant for obesity. However...

  9. Análise da influência do nistagmo espontâneo e pré-calórico na vectoeletronistagmografia Analysis of spontaneous and per caloric nistagmus and its influence in vectonystagmography

    OpenAIRE

    Gisiane Munaro; Pricila Sleifer; Fleming Salvador Pedroso

    2009-01-01

    OBJETIVO: verificar a ocorrência do nistagmo espontâneo / pré-calórico, sua direção, cálculo da velocidade angular média e real da componente lenta, sua influência quantitativa e qualitativa nas pro-vas calórica e rotatória em pacientes com sintomas vestibulares MÉTODOS: no período de janeiro a abril de 2006, 88 pacientes foram avaliados na Clínica de Audiologia do Centro Diagnóstico Mãe de Deus Center, em Porto Alegre, por Vectoeletronistagmografia computadorizada. RESULTADOS: 33 pacientes (...

  10. Efeito da acidificação, fermentação e adição de cálcio na qualidade de couve-flor (Brassica oleraceae L. processada pelo calor Effect of acidification, fermentation and addition of calcium on the quality of canned cauliflower (Brassica oleraceae L.

    Directory of Open Access Journals (Sweden)

    J.N. Nogueira

    1993-05-01

    Full Text Available O presente trabalho foi desenvolvido com o objetivo de fornecer informações, não encontradas na literatura, sobre o efeito da acidificação (cinco ácidos orgânicos, fermentação e adição de cálcio na qualidade de couve-flor (cultivar Shiromaru III, processada pelo calor. A qualidade da couve-flor processada foi avaliada através de análise física, química, microbiológica e sensorial, após dois meses de armazenamento à temperatura ambiente. Os resultados mostraram a possibilidade de processar couve-flor enlatada, de alta qualidade, em pequenas indústrias, com redução de gastos em equipamentos, instalações e energia. O procedimento da acidificação oferece também uma segurança maior para o consumidor, pois elimina possíveis riscos de incidência do botulismo.The present work was developed to provide information currently lacking in the literature on the effect of acidification (five organic acids, fermentation and addition of calcium on the quality of canned cauliflower (cultivar Shiromaru III. Quality evaluation of the processed cauliflowers was determined by physical, chemical, microbiological and sensorial analysis, after a two month storage period at room temperature. The results showed the possibility of processing high quality canned cauliflowers by small canneries with low cost equipment and less energy requirement. The acidification procedure also implies in minor risks due to potential botulism incidence.

  11. Transient phase change induced by femtosecond light pulses in the spin ladder system α‧-NaV2O5

    Science.gov (United States)

    Suemoto, T.; Nakajima, M.; Aiba, M.; Isob, M.; Ueda, Y.

    2004-12-01

    Transient reflectance changes are studied for a spin ladder system α'-NaV 2O 5 in the temperature range from 4 K to room temperature (RT), by means of femtosecond pump-and-probe measurements. A large response with a slow rise (3 ps) and a slow decay (>400 ps) is found only below 34 K, the phase transition temperature of charge ordering. Analyzing the temperature dependence of the amplitude and the decay behavior of this response, the observed phenomenon is ascribed to a photo-induced transition from the low-temperature phase to a state similar to the high-temperature phase. The polarization properties indicate the produced entity is not identical with the high-temperature phase.

  12. Transient Numerical Simulation of the Melting and Solidification Behavior of NaNO3 Using a Wire Matrix for Enhancing the Heat Transfer

    Directory of Open Access Journals (Sweden)

    Martin Koller

    2016-03-01

    Full Text Available The paper presents the results of a transient numerical investigation of the melting and solidification process of sodium nitrate (NaNO3, which is used as phase change material. For enhancing the heat transfer to the sodium nitrate an aluminum wire matrix is used. The numerical simulation of the melting and solidification process was done with the enthalpy-porosity approach. The numerical analysis of the melting process has shown that apart from the first period of the charging process, where heat conduction is the main heat transfer mechanism, natural convection is the dominant heat transfer mechanism. The numerical investigation of the solidification process has shown that the dominant heat transfer mechanism is heat conduction. Based on the numerical results, the discharging process has been slower than the charging process. The performance of the charged and discharged power has shown that the wire matrix is an alternative method to enhance the heat transfer into the phase change material.

  13. Uma medida de calor específico sem calorímetro

    Directory of Open Access Journals (Sweden)

    Mattos Cristiano

    2003-01-01

    Full Text Available Várias técnicas têm sido desenvolvidas para se obter o calor específico de sólidos e líquidos, incluindo a construção de experimentos de baixo custo para o ensino médio. Neste trabalho propomos uma maneira simples de se obter o calor específico de sólidos e líquidos. Por meio de curvas de calibração de resfriamento podemos estimar graficamente a perda de calor do sistema para sua vizinhança, e medir o calor específico do alumínio. Esta aproximação permite introduzir uma discussão sobre o processo dinâmico da troca de calor entre dos corpos.

  14. Asymmetry Dependence of the Nuclear Caloric Curve

    CERN Document Server

    McIntosh, Alan B; Cammarata, Paul; Hagel, Kris; Heilborn, Lauren; Kohley, Zachary; Mabiala, Justin; May, Larry W; Marini, Paola; Raphelt, Andrew; Souliotis, George A; Wuenschel, Sara; Zarrella, Andrew; Yennello, Sherry J

    2012-01-01

    A basic feature of the nuclear equation of state is not yet understood: the dependence of the nuclear caloric curve on the neutron-proton asymmetry. Predictions of theoretical models differ on the magnitude and even the sign of this dependence. In this work, the nuclear caloric curve is examined for fully reconstructed quasi-projectiles around mass A=50. The caloric curve extracted with the momentum quadrupole fluctuation thermometer shows that the temperature varies linearly with quasi-projectile asymmetry (N-Z)/A. An increase in asymmetry of 0.15 units corresponds to a decrease in temperature on the order of 1 MeV. These results also highlight the importance of a full quasi-projectile reconstruction in the study of thermodynamic properties of hot nuclei.

  15. Actions of a hydrogen sulfide donor (NaHS) on transient sodium, persistent sodium, and voltage-gated calcium currents in neurons of the subfornical organ.

    Science.gov (United States)

    Kuksis, Markus; Ferguson, Alastair V

    2015-09-01

    Hydrogen sulfide (H2S) is an endogenously found gasotransmitter that has been implicated in a variety of beneficial physiological functions. This study was performed to investigate the cellular mechanisms underlying actions of H2S previously observed in subfornical organ (SFO), where H2S acts to regulate blood pressure through a depolarization of the membrane and an overall increase in the excitability of SFO neurons. We used whole cell patch-clamp electrophysiology in the voltage-clamp configuration to analyze the effect of 1 mM NaHS, an H2S donor, on voltage-gated potassium, sodium, and calcium currents. We observed no effect of NaHS on potassium currents; however, both voltage-gated sodium currents (persistent and transient) and the N-type calcium current had a depolarized activation curve and an enhanced peak-induced current in response to a series of voltage-step and ramp protocols run in the control and NaHS conditions. These effects were not responsible for the previously observed depolarization of the membrane potential, as depolarizing effects of H2S were still observed following block of these conductances with tetrodotoxin (5 μM) and ω-conotoxin-GVIA (100 nM). Our studies are the first to investigate the effect of H2S on a variety of voltage-gated conductances in a single brain area, and although they do not explain mechanisms underlying the depolarizing actions of H2S on SFO neurons, they provide evidence of potential mechanisms through which this gasotransmitter influences the excitability of neurons in this important brain area as a consequence of the modulation of multiple ion channels.

  16. Papel dos fluxos de calor latente e sensível em superfície associado a um caso de ciclogênese na Costa Leste da América do Sul Role of surface latent and sensible heat fluxes associated to a South America East Coast cyclogenesis case

    Directory of Open Access Journals (Sweden)

    Everson Dal Piva

    2008-12-01

    Full Text Available Neste estudo foram realizados experimentos numéricos com um modelo meteorológico regional a fim de verificar o impacto dos Fluxos de Calor Latente (FCL e Calor Sensível (FCS em superfície no desenvolvimento de um ciclone intenso ocorrido sobre a costa leste da região sudeste da América do Sul, entre os dias 24 e 26 de julho de 1998. A taxa de intensificação do ciclone foi reduzida em 6 hPa/24 h no experimento em que os FCL e FCS estavam ausentes. Verificou-se que a ausência do FCL apresentou maior impacto do que a ausência do FCS, fazendo com que a taxa de intensificação fosse reduzida em 6 hPa/24 h para o experimento sem FCL e permanecesse inalterada sem FCS, mas neste último a isóbara de menor valor no centro do ciclone ocupou uma área menor. A ausência dos FCL e FCS em superfície gerou uma camada mais seca e mais fria próxima à superfície oceânica, reduzindo a instabilidade potencial do ambiente e diminuindo a intensificação do ciclone. Concluiu-se, portanto que os FCL e FCS em superfície foram importantes antes da fase de mais rápido desenvolvimento do ciclone, agindo no sentido de preparar o ambiente para uma ciclogênese mais intensa, através do fornecimento de energia e umidade para a baixa troposfera. Na fase de mais rápido desenvolvimento, a energia e a umidade disponíveis nas camadas mais baixas da atmosfera (inseridos na fase anterior também foram importantes, permitindo ao ciclone se desenvolver mais intensamente do que ocorreria em um ambiente mais seco e menos instável termicamente.Numeric experiments were run with meteorological regional model with the purpose to verify the impact of both latent and sensible surface heat fluxes (FCL and FCS, respectively during the development of an intense east cost cyclone over southeastern region of South America from 24 to 26 July, 1998. The intensification rate of the cyclone was reduced by 6 hPa/24 h in the experiment where the FCL and FCS were absents. It was

  17. New developments in caloric materials for cooling applications

    Science.gov (United States)

    Crossley, S.; Mathur, N. D.; Moya, X.

    2015-06-01

    Caloric materials are in the spotlight as candidates for future environmentally friendly cooling technologies. We describe stimulating recent developments in the three caloric strands that are now being studied collectively, namely magnetocaloric, electrocaloric and mechanocaloric (elastocaloric or barocaloric) effects.

  18. New developments in caloric materials for cooling applications

    OpenAIRE

    Crossley, S.; Mathur, N. D.; Moya, X.

    2015-01-01

    Caloric materials are in the spotlight as candidates for future environmentally friendly cooling technologies. We describe stimulating recent developments in the three caloric strands that are now being studied collectively, namely magnetocaloric, electrocaloric and mechanocaloric (elastocaloric or barocaloric) effects.

  19. Epigenetic regulation of caloric restriction in aging

    Directory of Open Access Journals (Sweden)

    Daniel Michael

    2011-08-01

    Full Text Available Abstract The molecular mechanisms of aging are the subject of much research and have facilitated potential interventions to delay aging and aging-related degenerative diseases in humans. The aging process is frequently affected by environmental factors, and caloric restriction is by far the most effective and established environmental manipulation for extending lifespan in various animal models. However, the precise mechanisms by which caloric restriction affects lifespan are still not clear. Epigenetic mechanisms have recently been recognized as major contributors to nutrition-related longevity and aging control. Two primary epigenetic codes, DNA methylation and histone modification, are believed to dynamically influence chromatin structure, resulting in expression changes of relevant genes. In this review, we assess the current advances in epigenetic regulation in response to caloric restriction and how this affects cellular senescence, aging and potential extension of a healthy lifespan in humans. Enhanced understanding of the important role of epigenetics in the control of the aging process through caloric restriction may lead to clinical advances in the prevention and therapy of human aging-associated diseases.

  20. Conservación por calor

    OpenAIRE

    Cobos García, Angel; Díaz Rubio, Olga

    2011-01-01

    Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos por calor. Este método permite destruír ...

  1. Transferencia de calor a lechos empacados

    OpenAIRE

    Beltrán Feged, Alvaro; Bonilla Melendez, Alberto; Cancelado Arias, Miguel

    2012-01-01

    Consideremos el lecho de solidos granulados de la figura 1.El lecho esta a una temperatura u (z,t), y tiene un calor especifico  cs, que se toma constante. z es la altura del lecho, y t es el tiempo. A este lecho entran G unidades de masa de fluido por unidad de tiempo y de área de sección de lecho(1)(2)

  2. Efeito transiente de exercícios de flexibilidade na articulação do quadril sobre a marcha de idosas Transient effect of flexibility exercises in the hip joint on the gait of older women

    Directory of Open Access Journals (Sweden)

    Fabiano Cristopoliski

    2008-04-01

    Full Text Available A marcha é a atividade mais comum que o ser humano realiza, sendo uma habilidade motora fundamental para a locomoção. Contudo, o processo do envelhecimento é caracterizado pela redução gradativa da eficiência do aparelho locomotor, que ocorre pela diminuição da força e da massa muscular, assim como diminuição na flexibilidade. O estudo objetivou verificar o efeito transiente de uma sessão de exercícios de flexibilidade dos músculos extensores e flexores do quadril sobre a marcha de indivíduos idosos. Cinco idosas (67,0 ± 3,8 anos; 1,59 ± 0,07 m; 64,3 ± 15,3 Kg voluntariaram participar do estudo. A marcha dos sujeitos foi analisada antes e depois dos exercícios de flexibilidade. O protocolo consistiu em uma sessão de três séries de exercícios de flexibilidade de 30s do método estático, feitos para os músculos flexores e extensores da articulação do quadril. Após a sessão de flexibilidade, a marcha das participantes apresentou menor pico de inclinação anterior da pelve, maior pico de extensão e amplitude total de movimento da articulação do quadril, maior amplitude de movimento do joelho com maior ângulo de flexão durante a fase de balanço médio e maior altura de separação do pé ao solo (aumento esse de 28,6%. Os resultados mostram que imediatamente após a sessão dos exercícios de flexibilidade as mulheres idosas apresentaram mudanças no padrão da marcha nos quais algumas variáveis sugerem uma redução no risco de quedas. Os efeitos da idade sobre determinadas variáveis foram parcialmente revertidos e as participantes apresentaram um padrão da marcha mais similar aos adultos jovens que antes dos alongamentos.Gait is the most common activity performed by humans, being a fundamental motor ability to locomotion. However, ageing is characterized by a gradual reduction of the locomotor apparatus efficiency which occurs by the decrease in strength, muscle mass and flexibility. This study aimed to

  3. A novel experimental method for the measurement of the caloric curves of clusters

    CERN Document Server

    Chirot, Fabien; Zamith, Sébastien; Labastie, Pierre; L'Hermite, Jean-Marc; 10.1063/1.3000628

    2008-01-01

    A novel experimental scheme has been developed in order to measure the heat capacity of mass selected clusters. It is based on controlled sticking of atoms on clusters. This allows one to construct the caloric curve, thus determining the melting temperature and the latent heat of fusion in the case of first-order phase transitions. This method is model-free. It is transferable to many systems since the energy is brought to clusters through sticking collisions. As an example, it has been applied to Na\\_90\\^+ and Na\\_140\\^+. Our results are in good agreement with previous measurements.

  4. Caloric density of Loricariichthys platymetopon (Osteichthyes, Loricariidae in the Upper Paraná River floodplain, Brazil

    Directory of Open Access Journals (Sweden)

    Daniela Aparecida Garcia

    2010-10-01

    Full Text Available This study analyzed the muscle energy content (caloric density of L. platymetopon captured at different sites of the Upper Paraná River floodplain, and potential relationships between the content and various environmental variables (water temperature, oxygen dissolved in water, food availability, relative numeric abundance and biological variables (body size and reproductive cycle. Quarterly samplings from September 2006 to June 2007 in the lakes and rivers resulted in a sample of 739 specimens, whose muscle caloric density was determined using a calorimeter. Differences between the caloric averages of the males and females and among the different stages of gonadal development were not significant. Caloric density varied over time and space, with two seasonal variation trends. The intensity of the correlation between the caloric density and each environmental variable, as well as the type of correlation, varied according to the sampled site. Body size and reproductive cycle were not correlated with caloric density.Este estudo analisou o conteúdo de energia (densidade calórica de L. platymetopon capturados em diferentes locais da planície alagável do Alto Rio Paraná, e potenciais relações entre este conteúdo e várias variáveis ambientais (temperatura da água, oxigênio dissolvido na água, disponibilidade de alimento, abundância relativa numérica e variáveis biológicas (tamanho corpóreo e ciclo reprodutivo. Coletas trimestrais, de setembro/2006 a junho/2007, em lagos e rios, resultaram em uma amostra de 739 espécimes, cuja densidade calórica muscular foi determinada através de calorímetro. Diferenças entre as médias calóricas de machos e fêmeas e entre os estádios de desenvolvimento gonadal não foram significativas Densidade calórica variou sazonal e espacialmente, com duas tendências de variação sazonal. A intensidade da correlação entre densidade calórica e cada variável e cada variável ambiental, assim como

  5. Use of non-caloric edulcorants in children

    Directory of Open Access Journals (Sweden)

    Calzada León Raúl

    2014-07-01

    Full Text Available We analyze the health normativity for the denomination of non caloric edulcorants in Mexico, and the authorization for the use of natural and synthetic non caloric edulcorants in newborn and until puberty. Special emphasis was given to the consecutive points of safety required in order to assure that they are free of secondary effects. For each non caloric edulcorant available in Mexico, we looked into the studies which mention their side effects in terms of growth and overall.

  6. Modeling microscale heat transfer using Calore.

    Energy Technology Data Exchange (ETDEWEB)

    Gallis, Michail A.; Rader, Daniel John; Wong, Chung-Nin Channy; Bainbridge, Bruce L.; Torczynski, John Robert; Piekos, Edward Stanley

    2005-09-01

    Modeling microscale heat transfer with the computational-heat-transfer code Calore is discussed. Microscale heat transfer problems differ from their macroscopic counterparts in that conductive heat transfer in both solid and gaseous materials may have important noncontinuum effects. In a solid material, three noncontinuum effects are considered: ballistic transport of phonons across a thin film, scattering of phonons from surface roughness at a gas-solid interface, and scattering of phonons from grain boundaries within the solid material. These processes are modeled for polycrystalline silicon, and the thermal-conductivity values predicted by these models are compared to experimental data. In a gaseous material, two noncontinuum effects are considered: ballistic transport of gas molecules across a thin gap and accommodation of gas molecules to solid conditions when reflecting from a solid surface. These processes are modeled for arbitrary gases by allowing the gas and solid temperatures across a gas-solid interface to differ: a finite heat transfer coefficient (contact conductance) is imposed at the gas-solid interface so that the temperature difference is proportional to the normal heat flux. In this approach, the behavior of gas in the bulk is not changed from behavior observed under macroscopic conditions. These models are implemented in Calore as user subroutines. The user subroutines reside within Sandia's Source Forge server, where they undergo version control and regression testing and are available to analysts needing these capabilities. A Calore simulation is presented that exercises these models for a heated microbeam separated from an ambient-temperature substrate by a thin gas-filled gap. Failure to use the noncontinuum heat transfer models for the solid and the gas causes the maximum temperature of the microbeam to be significantly underpredicted.

  7. A new light on caloric test--what was disclosed by three dimensional analysis of caloric nystagmus?

    Science.gov (United States)

    Arai, Y.

    2001-01-01

    For better understanding of caloric nystagmus, this phenomenon will be reviewed historically in three stages. 1) The first light on caloric nystagmus was thrown by Barany 1906. Through direct observation of eye movements, Barany established the caloric test as an important tool to determine the side of lesion for vertigo. 2) The second light is shed by electrooculogram (EOG) from the late 1950th. EOG enabled qualitative analysis of caloric nystagmus, and proved Barany's convection theory, but resulted in neglect of vertical and roll eye movements. 3) The third light is gained by 3D recording of eye movements started from the late 1980th. 3D recordings of eye movements enabled us to analyze the spatial orientation of caloric nystagmus, and disclose the close correlation of the nystagmus components in the head vertical and the space vertical planes, suggesting a contribution of the velocity storage integrator. The 3D property of caloric nystagmus will be explained in detail.

  8. A Dissociation Between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    Science.gov (United States)

    Delogu, Franco; Huddas, Claire; Steven, Katelyn; Hachem, Souheila; Lodhia, Luv; Fernandez, Ryan; Logerstedt, Macee

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize, if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks’ sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers’ choices. PMID:26858681

  9. A Dissociation Between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks.

    Science.gov (United States)

    Delogu, Franco; Huddas, Claire; Steven, Katelyn; Hachem, Souheila; Lodhia, Luv; Fernandez, Ryan; Logerstedt, Macee

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize, if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks' sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers' choices.

  10. A Dissociation between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    Directory of Open Access Journals (Sweden)

    Franco eDelogu

    2016-01-01

    Full Text Available Consumption of sugar-sweetened beverages (SSBs is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs. 55 college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks’ sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers’ choices.

  11. Caloric versus low-caloric sweeteners: Can the body be fooled?

    NARCIS (Netherlands)

    Smeets, P.A.M.

    2010-01-01

    Low-caloric artificial sweeteners have been around for several decades now. Still, the debate over their usefulness in decreasing energy intake is ongoing. In principle, replacing sugar-containing foods with 'light' versions will lead to decreased energy intake. However, the reality of food intake b

  12. Fluid-structural dynamics of ground-based and microgravity caloric tests

    Science.gov (United States)

    Kassemi, M.; Oas, J. G.; Deserranno, Dimitri

    2005-01-01

    Microgravity caloric tests aboard the 1983 SpaceLab1 mission produced nystagmus results with an intensity comparable to those elicited during post- and pre- flight tests, thus contradicting the basic premise of Barany's convection hypothesis for caloric stimulation. In this work, we present a dynamic fluid structural analysis of the caloric stimulation of the lateral semicircular canal based on two simultaneous driving forces for the endolymphatic flow: natural convection driven by the temperature-dependent density variation in the bulk fluid and expansive convection caused by direct volumetric displacement of the endolymph during the thermal irrigation. Direct numerical simulations indicate that on earth, the natural convection mechanism is dominant. But in the microgravity environment of orbiting spacecraft, where buoyancy effects are mitigated, expansive convection becomes the sole mechanism for producing cupular displacement. A series of transient 1 g and microgravity case studies are presented to delineate the differences between the dynamics of the 1 g and microgravity endolymphatic flows. The impact of these different flow dynamics on the endolymph-cupula fluid-structural interactions is also analyzed based on the time evolutions of cupular displacement and velocity and the transcupular pressure differences.

  13. Calorie anticipation alters food intake after low-caloric not high-caloric preloads.

    Science.gov (United States)

    Hogenkamp, P S; Cedernaes, J; Chapman, C D; Vogel, H; Hjorth, O C; Zarei, S; Lundberg, L S; Brooks, S J; Dickson, S L; Benedict, C; Schiöth, H B

    2013-08-01

    Cognitive factors and anticipation are known to influence food intake. The current study examined the effect of anticipation and actual consumption of food on hormone (ghrelin, cortisol, and insulin) and glucose levels, appetite and ad libitum intake, to assess whether changes in hormone levels might explain the predicted differences in subsequent food intake. During four breakfast sessions, participants consumed a yogurt preload that was either low caloric (LC: 180 kcal/300 g) or high caloric (HC: 530 kcal/300 g) and was provided with either consistent or inconsistent calorie information (i.e., stating the caloric content of the preload was low or high). Appetite ratings and hormone and glucose levels were measured at baseline (t = 0), after providing the calorie information about the preload (t = 20), after consumption of the preload (t = 40), and just before ad libitum intake (t = 60). Ad libitum intake was lower after HC preloads (as compared to LC preloads; P Intake after LC preloads was higher when provided with (consistent) LC information (467±254 kcal) as compared to (inconsistent) HC information (346±210 kcal), but intake after the HC preloads did not depend on the information provided (LC information: 290±178 kcal, HC information: 333±179 kcal; caloric load*information P = 0.03). Hormone levels did not respond in an anticipatory manner, and the post-prandial responses depended on actual calories consumed. These results suggest that both cognitive and physiological information determine food intake. When actual caloric intake was sufficient to produce physiological satiety, cognitive factors played no role; however, when physiological satiety was limited, cognitively induced satiety reduced intake to comparable levels. Copyright © 2012 The Obesity Society.

  14. Electrochemical noise transient analysis for 316 and Duplex 2205 stainless steels in NaCl and FeCl; Analisis de los transitorios de ruido electroquimico para aceros inoxidables 316 Y - DUPLEX 2205 en NaCl Y FeCl

    Energy Technology Data Exchange (ETDEWEB)

    Almeraya-Calderaon, F.; Estupinan, F.; Zambrano, P.; Martinez-Villafane, A.; Borunda, A.; Colas, R.; Gaona-Tiburcio, C.

    2012-11-01

    This work shows the results obtained from electrochemical noise measurements for different materials exhibiting pitting corrosion. The transients presented in the potential and current time, correlates with the scanning electron microscopy (SEM) surface analysis. Electrochemical measurements were made at different exposure times to obtain the correlation. The materials used were stainless steel austenitic 316 and duplex 2205, immersed in ferric chloride (FeCl3) and sodium chloride (NaCl) electrolytes. SEM analysis shows that the transients observed in the time series, really correspond to the activity of pit nucleation developed over the surface of the electrodes. (Author) 31 refs.

  15. New developments in caloric materials for cooling applications

    Directory of Open Access Journals (Sweden)

    S. Crossley

    2015-06-01

    Full Text Available Caloric materials are in the spotlight as candidates for future environmentally friendly cooling technologies. We describe stimulating recent developments in the three caloric strands that are now being studied collectively, namely magnetocaloric, electrocaloric and mechanocaloric (elastocaloric or barocaloric effects.

  16. Caloric sxpense in daily and labor activities of cycling postmen

    Directory of Open Access Journals (Sweden)

    Milton Carlos Della Giustina

    2004-12-01

    Full Text Available The study aimed to identify lifestyle behaviors and to quantify caloric expenditure in daily and labor activities of bike postmen (employees from CORREIOS - Brazilian Postal Services of the city of São José – SC – Brazil. The methodology used an interview using the IPAQ questionnaire, anthropometric measurements and records of daily activities (measuring time spent in selecting mail, and in delivering it as well as monitoring speed and time during cycling. The caloric expenditure was estimated by using body mass and mean speed of delivering mail, which corresponds to 4 METs. From descriptive analyses of the data, a confidence interval scale was created. Twenty-three subjects composed the sample with mean age of 31.3 yrs (sd 6.3, body mass of 73.4 kg (sd 9.6, stature of 1.74 m (sd 0.05 and IMC of 24.4 kg.m-2 (sd 2.9. The results indicated that the majority of subjects had healthy lifestyles. Mean daily caloric expenditure in selecting mail was 590 kcal.day-1 and in delivering it was 1818 kcal.day -1 . Daily labor activities of bike postmen were a positive factor of their health-related physical fitness components. RESUMO Com o objetivo de conhecer hábitos de vida e estimar gasto calórico despendido, esse estudo se realizou com carteiros que utilizam a bicicleta como meio de locomoção para a entrega domiciliar, em São José/SC. A investigação constou de entrevista dirigida, utilizando-se o questionário sobre hábitos de atividade física (IPAQ, coleta de dados antropométricos e acompanhamento de um dia normal de entrega de correspondências, observando-se tempo despendido na seleção e entrega de correspondências (monitorando velocidade da pedalada. O estudo do gasto calórico nas atividades de trabalho foi estimado conforme tempo despendido na triagem das cartas e a entrega (calculado através do peso do indivíduo e da velocidade média de entrega pedalando, correspondente a 4 METs. Os dados foram analisados através de escalas

  17. Caloric curves of atomic nuclei and other small systems

    CERN Document Server

    Schiller, A; Hjorth-Jensen, M; Rekstad, J; Siem, S

    2003-01-01

    Caloric curves have traditionally been derived within the microcanonical ensemble via dS/dE=1/T or within the canonical ensemble via E=T^2*d(ln Z)/dT. In the thermodynamical limit, i.e., for large systems, both caloric curves give the same result. For small systems like nuclei, the two caloric curves are in general different from each other and neither one is reasonable. Using dS/dE=1/T, spurious structures like negative temperatures and negative heat capacities can occur and have indeed been discussed in the literature. Using E=T^2*d(ln Z)/dT a very featureless caloric curve is obtained which generally smoothes too much over structural changes in the system. A new approach for caloric curves based on the two-dimensional probability distribution P(E,T) will be discussed.

  18. COMPARAÇÃO ENTRE TÉCNICAS NUMÉRICAS PARA A RESOLUÇÃO DO PROBLEMA DE TRANSFERÊNCIA DE CALOR EM ALIMENTOS ENLATADOS

    Directory of Open Access Journals (Sweden)

    A.D. RODRIGUES

    1998-05-01

    Full Text Available Este trabalho apresenta a comparação das técnicas de resolução numérica de Diferenças Finitas e Runge-Kutta-Gill de 4a ordem com passo de integração variável para a simulação do modelo de transferência de calor em regime transiente bidimensional em coordenadas cilíndricas e unidimensional em coordenadas esféricas, aplicado a alimentos enlatados processados em autoclave, observando-se a rapidez e a precisão de integração comparados aos perfis reais de tempo/temperatura, incluindo desvios de processo. Além disso, uma análise de sensibilidade paramétrica na difusividade térmica foi realizada na tentativa de quantificar a influência que essa propriedade possui na resolução numérica. Para tanto, foram realizados ensaios de penetração de calor em autoclave a vapor, utilizando-se latas cilíndricas de 75x90 e 100x110 contendo simulantes de alimentos com características de aquecimento por condução e convecção.This work presents a comparison of the integration quickness and precision between the techniques of numerical resolution of Finite Differences and Runge-Kutta-Gill of fourth order with variable integration pass, to do simulation of the unsteady-state heat transfer model, two-dimensional in cylindrical coordinates and one-dimensional in spherical coordinates, applied to canned foods processed in retorts, showing advantages for the technique of Runge-Kutta-Gill. It was also accomplished a parametric sensitivity analysis in the thermal diffusivity indicating a great influence of this parameter in the numerical solution. The mathematical simulation were compared with results of real heat penetration tests done in steam retort, using cylindrical cans filled with bentonite suspensions simulating foods with heat characteristics resembling heat conduction and heat convection.

  19. Estudo da transferência de calor durante o congelamento de cortes de aves em caixas de papelão ondulado

    OpenAIRE

    Santos, Clarice de Ávila

    2005-01-01

    Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Engenharia de Alimentos O congelamento de produtos alimentícios é um processo complexo que envolve transferência de calor com mudança de fase e ocorre em uma faixa de temperaturas. É realizado, predominantemente, em túneis com convecção forçada de ar, onde o escoamento de ar ocorre em regime turbulento e a transferência de calor do produto para o ar em regime transiente. Quando...

  20. MODELADO DE DINÁMICA DE FLUIDOS Y TRANSFERENCIA DE CALOR Y MASA EN PROCESOS AGROALIMENTARIOS POR MÉTODO DE VOLÚMENES FINITOS

    OpenAIRE

    Moraga, Nelson O.; Zambra, Carlos E.; Torres, Paul B.; Lemus-Mondaca, Roberto A.

    2011-01-01

    Se describe la transferencia de momento, calor y masa transiente bi-dimensional en procesos agroalimentarios. Estos procesos son: la pre-cosecha y luego la deshidratación por aire caliente de frutas. La metodología incluye modelación matemática y simulación computacional para describir la convección y difusión de calor y masa conjugada que resulta de la interacción entre el alimento y el aire. El modelo matemático emplea las ecuaciones diferenciales parciales no lineales acopladas de continu...

  1. Caloric vestibular stimulation as a treatment for conversion disorder: A case report and medical hypothesis

    Directory of Open Access Journals (Sweden)

    Michael eNoll-Hussong

    2014-06-01

    Full Text Available Conversion disorder is a medical condition in which a person has paralysis, blindness, or other neurological symptoms that cannot be clearly explained physiologically. To date, there is neither specific nor conclusive treatment. In this paper, we draw together a number of disparate pieces of knowledge to propose a novel intervention to provide transient alleviation for this condition. As caloric vestibular stimulation (CVS has been demonstrated to modulate transiently a variety of cognitive functions associated with brain activations, especially in the temporal-parietal cortex, anterior cingulate cortex, and insular cortex, there is evidence to assume an effect in specific mental disorders. Therefore, we go on to hypothesize that lateralized cold vestibular caloric stimulation will be effective in treating conversion disorder and we present provisional evidence from one patient that supports this conclusion. If our hypothesis is correct, this will be the first time in psychiatry and neurology that a clinically well-known mental disorder, long considered difficult to understand and to treat, is relieved by a simple or common, non-invasive medical procedure.

  2. Conservación por calor

    OpenAIRE

    Cobos García, Angel; Díaz Rubio, Olga

    2011-01-01

    Grao en Nutrición Humana e Dietética Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos ...

  3. Caloric vestibular stimulation in aphasic syndrome

    Directory of Open Access Journals (Sweden)

    David eWilkinson

    2013-12-01

    Full Text Available Caloric vestibular stimulation (CVS is commonly used to diagnose brainstem disorder but its therapeutic application is much less established. Based on the finding that CVS increases blood flow to brain structures associated with language and communication, we assessed whether the procedure has potential to relieve symptoms of post-stroke aphasia. Three participants, each presenting with chronic, unilateral lesions to the left hemisphere, were administered daily CVS for 4 consecutive weeks. Relative to their pre-treatment baseline scores, two of the three participants showed significant improvement on both picture and responsive naming at immediate and one-week follow-up. One of these participants also showed improved sentence repetition, and another showed improved auditory word discrimination. No adverse reactions were reported. These data provide the first, albeit tentative, evidence that CVS may relieve expressive and receptive symptoms of aphasia. A larger, sham-controlled study is now needed to further assess efficacy.

  4. Calorie Anticipation Alters Food Intake After Low-Caloric but Not High-Caloric Preloads

    OpenAIRE

    Hogenkamp, Pleunie; Cedernaes, Jonathan; Chapman, Colin; Vogel, Heike; Hjorth, Olof; Zarei, Sanaz; Lundberg, Lina; Brooks, Samantha; Dickson, Suzanne; Benedict, Christian; Schiöth, Helgi

    2013-01-01

    Objective Cognitive factors and anticipation are known to influence food intake. The current study examined the effect of anticipation and actual consumption of food on hormone (ghrelin, cortisol, and insulin) and glucose levels, appetite and ad libitum intake, to assess whether changes in hormone levels might explain the predicted differences in subsequent food intake. Design and Methods During four breakfast sessions, participants consumed a yogurt preload that was either low caloric (LC: 1...

  5. A Dissociation between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    OpenAIRE

    Franco eDelogu; Claire eHuddas; Katelyn eSteven; Souheila eHachem; Luv eLodhia; Ryan eFernandez; Macee eLogerstedt

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms ...

  6. Analysis of caloric test responses in sudden hearing loss.

    Science.gov (United States)

    Shih, Cheng-Ping; Chou, Yu-Ching; Chen, Hsin-Chien; Lee, Jih-Chin; Chu, Yueng-Hsiang; Wang, Chih-Hung

    2017-02-01

    Sudden sensorineural hearing loss is characterized by a rapid-onset hearing loss that develops within 3 days. Vertigo may also be present. We conducted a retrospective study to investigate whether the severity of a loss of caloric function is associated with the initial hearing loss and with hearing recovery. Our study population was made up of 135 patients-67 men and 68 women, aged 25 to 71 years (mean: 50.9)-with sudden sensorineural hearing loss who had undergone bithermal caloric testing. We compared various patient factors according to patients' hearing level and their response to caloric testing. We also analyzed the canal paresis (CP) value in patients with an abnormal caloric response according to three factors: disease severity, vertigo, and hearing recovery, and we evaluated the correlation between the loss of caloric function and hearing outcomes. We found that an abnormal caloric response was significantly associated with a profound hearing loss at presentation, the presence of vertigo, and poor hearing recovery. Among patients with an abnormal caloric response, the CP value was significantly correlated with hearing recovery (r = 0.503, p = 0.001). Poor hearing recovery was seen in 80% of patients with a CP value of ≥40% but in only 25% of patients with a value of hearing recovery was worse in the patients with a CP value of ≥40% (p = 0.002). We conclude that a CP value of ≥40% is a significant prognostic factor for an unfavorable treatment outcome.

  7. Normal Caloric Responses during Acute Phase of Vestibular Neuritis

    Science.gov (United States)

    Lee, Sun-Uk; Park, Seong-Ho; Kim, Hyo-Jung; Koo, Ja-Won

    2016-01-01

    Background and Purpose We report a novel finding of caloric conversion from normal responses into unilateral paresis during the acute phase of vestibular neuritis (VN). Methods We recruited 893 patients with a diagnosis of VN at Dizziness Clinic of Seoul National University Bundang Hospital from 2003 to 2014 after excluding 28 patients with isolated inferior divisional VN (n=14) and those without follow-up tests despite normal caloric responses initially (n=14). We retrospectively analyzed the neurotological findings in four (0.5%) of the patients who showed a conversion from initially normal caloric responses into unilateral paresis during the acute phase. Results In those four patients, the initial caloric tests were performed within 2 days of symptom onset, and conversion into unilateral caloric paresis was documented 1–4 days later. The clinical and laboratory findings during the initial evaluation were consistent with VN in all four patients except for normal findings in bedside head impulse tests in one of them. Conclusions Normal findings in caloric tests should be interpreted with caution during the acute phase of suspected VN. Follow-up evaluation should be considered when the findings of the initial caloric test are normal, but VN remains the most plausible diagnosis. PMID:26932259

  8. Characteristics of non caloric dulcorants and their use in children

    Directory of Open Access Journals (Sweden)

    Calzada León Raúl

    2014-07-01

    Full Text Available This is a descriptive review of the elaboration routes, the physical and chemical characteristics, metabolism and clearance, sweetener level, residual flavor, maximal recommended ingestion, security levels and the assessment of growth and development problems in children (from newborns, including prematures, to the end of puberty, of the main no caloric edulcorants used in Mexico. The no caloric edulcorants included in this review are: aspartame, acesulfame-K, sucralose, sacarin, ciclamates, thaumatin, D- tagatose, estevia and alitame.

  9. Effective nucleon mass and the nuclear caloric curve

    CERN Document Server

    Shetty, D V; Galanopoulos, S; Yennello, S J

    2009-01-01

    Assuming a schematic form of the nucleon effective mass as a function of nuclear excitation energy and mass, we provide a simple explanation for understanding the experimentally observed mass dependence of the nuclear caloric curve. It is observed that the excitation energy at which the caloric curve enters into a plateau region, could be sensitive to the nuclear mass evolution of the effective nucleon mass.

  10. Interpretação e utilidade da prova calórica Interpretation and use of caloric testing

    Directory of Open Access Journals (Sweden)

    Denise Utsch Gonçalves

    2008-06-01

    Full Text Available A prova calórica é o teste da avaliação otoneurológica que verifica a integridade do reflexo vestíbulo-ocular e possibilita avaliar cada labirinto separadamente. Os principais aspectos relacionados à realização, interpretação e utilidade da prova calórica foram revistos. MÉTODOS: Realizou-se revisão sistemática sobre as publicações ocorridas nos últimos cem anos sobre o assunto. Incluíram-se artigos originais transversais e longitudinais, de revisão e meta-análise. Excluíram-se revisões de papeleta, relatos de caso e editoriais. Os descritores utilizados foram: prova calórica, nistagmo, sistema vestibular, preponderância direcional, predomínio labiríntico, teste calórico monotermal, teste calórico com água gelada, fenômeno de Bell. Pesquisou-se as bases de dados COCHRAINE, MEDLINE, LILACS, CAPES. RESULTADOS: De 818 resumos de artigos, selecionou-se inicialmente 93 que preenchiam os critérios de inclusão. A leitura dos artigos resultou na seleção final de 55. Na análise dos artigos, enfatizou-se na discussão fundamentos da prova calórica, tipos de estimulação utilizados, prova calórica monotermal e com água gelada, questões relacionadas à interpretação dos resultados, variáveis e artefatos. COMENTÁRIOS FINAIS: os valores de referência utilizados na prova calórica podem variar de serviço para serviço, com ponto de corte definido a partir de estudos locais. Semiotécnica cuidadosa é fundamental para elevar a sensibilidade do exame.Caloric testing is an otoneurologic evaluation of the status of the vestibular-ocular reflex; it allows an evaluation of each labyrinth separately. The main aspects on the use and interpretation of caloric testing are reviewed. METHOD: A systematic review of papers published in the past one hundred years on caloric testing was undertaken. The inclusion criteria were: cross-sectional, longitudinal, original articles, reviews and meta-analyses. Reviews of patient charts

  11. Transferência de calor e controle de temperatura em tubos capilares utilizados em eletroforese capilar

    OpenAIRE

    Rodrigo Danieli

    2005-01-01

    Este trabalho tem por objetivo estudar a transferência de calor em tubos capilares cilíndricos utilizados na técnica de separação de moléculas denominada Eletroforese Capilar. Esta técnica é usada, por exemplo, na análise de biomoléculas e no sequenciamento de DNA, onde o controle da temperatura está diretamente ligado ao desempenho destes métodos e à qualidade dos resultados. Para empregar esta técnica, tensões elétricas da ordem de 20 kV são aplicadas entre as extremidades dos tubos capilar...

  12. Caloric vestibular stimulation as a treatment for conversion disorder: a case report and medical hypothesis.

    Science.gov (United States)

    Noll-Hussong, Michael; Holzapfel, Sabrina; Pokorny, Dan; Herberger, Simone

    2014-01-01

    Conversion disorder is a medical condition in which a person has paralysis, blindness, or other neurological symptoms that cannot be clearly explained physiologically. To date, there is neither specific nor conclusive treatment. In this paper, we draw together a number of disparate pieces of knowledge to propose a novel intervention to provide transient alleviation for this condition. As caloric vestibular stimulation has been demonstrated to modulate a variety of cognitive functions associated with brain activations, especially in the temporal-parietal cortex, anterior cingulate cortex, and insular cortex, there is evidence to assume an effect in specific mental disorders. Therefore, we go on to hypothesize that lateralized cold vestibular caloric stimulation will be effective in treating conversion disorder and we present provisional evidence from one patient that supports this conclusion. If our hypothesis is correct, this will be the first time in psychiatry and neurology that a clinically well-known mental disorder, long considered difficult to understand and to treat, is relieved by a simple or common, non-invasive medical procedure.

  13. Changes of ampulla pressure in the semicircular canal of pigeons by caloric stimulation

    Science.gov (United States)

    Wada, Yoshiro; Suzuki, Hiroyuki; Watanabe, Satoru

    Still now several hypotheses about the mechanisms of the caloric nystagmus have been in conclusive. In this study we confirmed the convection effect and the volume change effect of the endolymph in horizontal semicircular canal following the caloric stimulation using pigeons ( Columba livia). Although the direction of the caloric nystagmus depended on the head position and the stimulus site of calorization, the caloric nystagmus disappeared after plugging of horizontal semicircular canal. On the other hand, the ampulla pressure increased by cold calorization and decreased by hot calorization and these pressure changes had no relation to the head position. These results show that the main role of the mechanisms of the caloric nystagmus under 1G is the convection effect but the volume change effect may act on the caloric nystagmus not only under 1G but also under microgravity.

  14. Cinética da transferência de calor em materiais com mudança de fase

    OpenAIRE

    Vitorino, Nuno Miguel Dias

    2013-01-01

    É extensa a bibliografia dedicada a potenciais aplicações de materiais com mudança de fase na regulação térmica e no armazenamento de calor ou de frio. No entanto, a baixa condutividade térmica impõe limitações numa grande diversidade de aplicações com exigências críticas em termos de tempo de resposta curto ou com requisitos de elevada potência em ciclos de carga/descarga de calor latente. Foram desenvolvidos códigos numéricos no sentido de obter soluções precisas para descrever a c...

  15. Automobilismo: no calor da competição Automovilismo: en el calor de la competición Car racing: in the heat of competition

    Directory of Open Access Journals (Sweden)

    Luiz Oswaldo Carneiro Rodrigues

    2004-06-01

    Full Text Available O presente artigo questiona o papel do calor como um fator de risco adicional para o acidente que vitimou Ayrton Senna. O automobilismo de competição constitui um desafio biológico, uma situação estressante do ponto de vista mental e físico. A manutenção da performance depende da disponibilidade de carboidratos e oxigênio, hidratação adequada e temperatura interna constante entre 37 e 38 graus centígrados. A dissipação do calor produzido pelo metabolismo ocorre através do aumento do fluxo de sangue para pele e produção de suor e manter a temperatura cerebral constante se constitui num problema permanente. Verificou-se experimentalmente que a energia necessária para dirigir um automóvel de corrida é comparável a um esporte como o voleibol. Durante uma corrida, o indivíduo está exposto a um microambiente quente na cabina, que pode atingir 50ºC, gerado por fontes de calor mecânicas e ambientais. O bloqueio da evaporação do suor pelo macacão resulta em umidade e desconforto pessoal, o que implica maior esforço mental para dirigir o carro. As medidas contra o calor começam antes da corrida, cuidando-se do estado nutricional, da hidratação e principalmente do condicionamento físico através de exercícios aeróbios regulares e adequados, que permitem aumentar a capacidade de trabalho e a tolerância ao calor, o que resulta em menor fadiga durante a corrida. Outro procedimento importante deveria ser a aclimatação prévia dos pilotos aos ambientes quentes e úmidos. Deve-se fazer o possível para reduzir o aquecimento do veículo e respeitar o sistema de bandeiras de advertência para os riscos de hipertermia. Em conclusão, embora Ayrton Senna fosse um indivíduo com maior risco de desenvolver hipertermia, independentemente de outras causas, não parece ter havido tempo de corrida suficiente para haver produção de calor metabólico capaz de aumentar excessivamente a temperatura interna do piloto nas condi

  16. Modeling and design aspects of active caloric regenerators

    Science.gov (United States)

    Engelbrecht, Kurt

    2015-03-01

    A cooling device based on a solid caloric material using, for example, the elastocaloric, magnetocaloric, barocaloric or electrocaloric effect has the potential to replace vapor-compression based systems for a variety of applications. Any caloric device using a solid refrigerant may benefit from using a regenerative cycle to increase the operating temperature span. This presentation shows how all active caloric regenerators can be modeled using similar techniques and how they are related to passive regenerator performance. The advantages and disadvantages of using a regenerative cycle are also discussed. The issue of hysteresis in caloric materials is investigated from a system/thermodynamic standpoint and the effects on cooling power and efficiency are quantified using a numerical model of an active regenerator using model caloric materials with assumed properties. The implementation in a working device will be discussed for elastocaloric and magnetocaloric cooling devices. It is shown that demagnetization effects for magnetocaloric systems and stress concentration effects in elastocaloric system reduce the overall effect in the regenerator and care must be taken in regenerator design for both technologies. Other loss mechanisms outside the regenerator such as heat leaks are also discussed. Finally, experimental results for active magnetic regenerative cooler are given for a range of operating conditions. The most recently published device uses a regenerator consisting of Gd and three alloys of GdY and has demonstrated a COP over 3.

  17. Transient osteoporosis.

    Science.gov (United States)

    Korompilias, Anastasios V; Karantanas, Apostolos H; Lykissas, Marios G; Beris, Alexandros E

    2008-08-01

    Transient osteoporosis is characterized primarily by bone marrow edema. The disease most commonly affects the hip, knee, and ankle in middle-aged men. Its cause remains unknown. The hallmark that separates transient osteoporosis from other conditions presenting with a bone marrow edema pattern is its self-limited nature. Laboratory tests usually do not contribute to the diagnosis. Plain radiographs may reveal regional osseous demineralization. Magnetic resonance imaging is used primarily for early diagnosis and monitoring disease progression. Early differentiation from more aggressive conditions with long-term sequelae is essential to avoid unnecessary treatment. Clinical entities such as transient osteoporosis of the hip and regional migratory osteoporosis are spontaneously resolving conditions. However, early differential diagnosis and surgical treatment are crucial for the patient with osteonecrosis of the hip or knee.

  18. [A caloric vestibular test with increased positive evidence (author's transl)].

    Science.gov (United States)

    Kurzeja, A; Strauss, P; Kapell, H

    1979-12-01

    A decrease of the variance of a caloric test would increase the importance of the statement of this test. An important source of variance are the differences concerning the timecourse of the induced heat wave, determined by the different anatomic conditions in the petrous bone, particularly the pneumatisation. A constant temperature gradient is obtained by the irigation in a pessimum position with the head flexed 30 degrees to the front. This temperature gradient evokes immediately a constant maximum vestibular stimulus after having reflected the head 90 degrees to the back. Comparing this new method with the traditional irrigation, one can state an important reduction of variance. The dependence of the nystagumus response on caloric irrigation of the petrous bone demands a X-ray-examination according to the technique of Schüller before starting with the caloric examination. In case of differences between the right and left sides the described test would be necessary in our opinion.

  19. Safety assessment and caloric value of partially hydrolyzed guar gum.

    Science.gov (United States)

    Finley, John W; Soto-Vaca, Adriana; Heimbach, James; Rao, T P; Juneja, Lekh Raj; Slavin, Joanne; Fahey, George C

    2013-02-27

    Guar gum and partially hydrolyzed guar gum (PHGG) are food ingredients that have been available for many years. PHGG is the partially hydrolyzed product from guar gum obtained from the Indian cluster bean (Cyanopsis tetragonolopus). The gum (CAS Registry No. 9000-30-0) is composed of galactomannan, a gel-forming polysaccharide with a molecular weight ranging from 200 to 300 kDa. The intact and partially hydrolyzed forms have multiple food applications. The intact material can be used to control the viscosity, stability, and texture of foods. PHGG is highly soluble and has little physical impact on foods. Both forms are indigestible but are excellent sources of fermentable dietary fiber. The caloric value of intact guar gum is accepted as 2.0, whereas the caloric value of PHGG has not been firmly established. It is the goal of this paper to review the chemistry, safety, in vivo effects, and caloric value of PHGG.

  20. El clima de las ciudades: isla de calor de Salamanca

    Directory of Open Access Journals (Sweden)

    Mª Salud Alonso García

    2004-12-01

    Full Text Available En este trabajo se ha determinado la existencia de la isla de calor urbana (ICU, en una ciudad de tamaño medio, con un clima extremado y focos industriales de poca actividad. Con lo que se puede comprobar cómo afecta el calentamiento urbano a ciudades de estas características, pudiendo influir en los seres vivos de la zona. La existencia del fenómeno isla de calor, y su evolución en el tiempo, se han observado comparando los datos de temperatura registrados en una estación meteorológica situada en la ciudad, con los de otra estación fuera del radio de acción de la urbe, durante el período 1996-1998. Se han detectado dos fenómenos: la isla de calor nocturna, cuando la diferencia térmica entre la ciudad y la zona rural es positiva, que presenta sus valores más altos en otoño, y la isla de calor diurna, cuando la diferencia es negativa, que presenta sus valores más altos en primavera. Realizando un estudio estadístico de la evolución anual de la isla de calor nocturna en Salamanca, podemos definir isla de calor débil si su intensidad es inferior a 2 oC, moderada si se encuentra entre 2 oC y 4 oC e intensa si supera los 4 oC.

  1. Frequency-dependent friction and its significance for liquid pipeline simulation; Influencia do fator de atrito com dependencia da frequencia na simulacao de transientes em oleodutos

    Energy Technology Data Exchange (ETDEWEB)

    Tepedino, Alexandre F. [TRANSPETRO - PETROBRAS Transporte S.A., Rio de Janeiro, RJ (Brazil); Rachid, Felipe B. Freitas [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica. Lab. de Transporte de Liquidos e Gases

    2008-07-01

    Unsteady liquid flow in pipelines is usually described by using one-dimensional models and, in a procedure referred to as quasi-steady approximation, friction losses are estimated by formulae derived for steady state flow conditions. The assumption is that the friction loss during transient flow conditions can be approximated by the friction loss obtained for a steady flow with the same average velocity. However, during unsteady flow conditions the velocity profile can be considerably different from the steady flow. The shear stress at the pipe wall and the mean velocity are not in phase. Therefore, friction losses computed according to the quasi-steady approximation are inaccurate. To overcome this, the concept of frequency-dependent friction was proposed, including the time history of the mean flow velocity and acceleration, resulting in better correlation to experimental data. This work presents an investigation of situations in which the use of a frequency-dependent friction model could bring additional improvement for the petroleum and products pipeline simulation. To do so, through computer simulations, the predictions of both quasi-steady and unsteady friction models, for short and long lines, operating under a range of Reynolds numbers, are compared and the significance of the friction model is evaluated. (author)

  2. Constrained caloric curves and phase transition for hot nuclei

    CERN Document Server

    Borderie, Bernard; Rivet, M F; Raduta, Ad R; Ademard, G; Bonnet, E; Bougault, R; Chbihi, A; Frankland, J D; Galichet, E; Gruyer, D; Guinet, D; Lautesse, P; Neindre, N Le; Lopez, O; Marini, P; Parlog, M; Pawlowski, P; Rosato, E; Roy, R; Vigilante, M

    2013-01-01

    Simulations based on experimental data obtained from multifragmenting quasi-fused nuclei produced in central $^{129}$Xe + $^{nat}$Sn collisions have been used to deduce event by event freeze-out properties in the thermal excitation energy range 4-12 AMeV [Nucl. Phys. A809 (2008) 111]. From these properties and the temperatures deduced from proton transverse momentum fluctuations, constrained caloric curves have been built. At constant average volumes caloric curves exhibit a monotonic behaviour whereas for constrained pressures a backbending is observed. Such results support the existence of a first order phase transition for hot nuclei.

  3. Aplasia transitória da série vermelha na anemia falciforme Transient red cell aplasia in sickle cell disease

    Directory of Open Access Journals (Sweden)

    Mônica P. A. Veríssimo

    2007-09-01

    Full Text Available A doença falciforme, devido à vida média encurtada das hemácias, pelo quadro de hemólise crônica, pode apresentar um quadro clínico grave de anemia quando ocorre supressão da eritropoese devida à infecção pelo Parvovírus humano B19. O quadro clínico apresenta-se com febre, que pode preceder a anemia grave, fraqueza e mal- estar, além de sinais laboratoriais como queda da hemoglobina e reticulocitopenia importante. Diagnóstico laboratorial pode ser por imunofluorescência ou ensaio enzimático. O tratamento é a transfusão de concentrado de hemácias. Pode haver complicações associadas a esta infecção, tais como seqüestro esplênico, seqüestro hepático, síndrome torácica aguda, síndrome nefrótica, meningoencefalite e acidente vascular cerebral. Estratégias de prevenção poderão mudar a morbi-mortalidade desta condição no paciente portador de doença falciforme.Sickle cell disease due to shortened life span of red blood cells by hemolysis, may present with severe anemia when erythropoietic suppression occurs due to infection by the Human parvovirus B19. The clinical presentation presents with fever, which may precede transient red cell aplasia, as well as laboratorial signs such as a drop in hemoglobin and significant reticulo cytopenia. Laboratorial diagnosis may be by immunofluorescence or enzymatic assays. Treatment is achieved by transfusion of packed red blood cells. Complications may be associated to this infection, including splenic and hepatic sequestration, acute chest syndrome, nephrotic syndrome, meningoencephalitis and strokes. Strategies of prevention are able to change the morbidity and mortality of this condition in sickle cell disease patients.

  4. CALOR87: HETC87, MICAP, EGS4, and SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, T.A.; Alsmiller, F.S.; Alsmiller, R.G. Jr.; Bishop, B.L.; Hermann, O.W.; Johnson, J.O.

    1987-01-01

    A brief history of CALOR (HETC, EGS, MICAP, SPECT) is presented to indicate the evolution of this code system. Details concerning the current modifications and additions to the high-energy transport code, HETC, are also presented and new comparisons with experimental data are included to verify the new physics improvements. 27 refs., 5 figs.

  5. Influence of caloric intake on experimental carcinogenesis: a review.

    Science.gov (United States)

    Kritchevsky, D; Klurfeld, D M

    1986-01-01

    The effect of caloric intake on tumor growth has been recognized for over 70 years. Inhibition of tumor growth depends primarily on the extent of caloric restriction, but tumor type, animal strain, and dietary composition all exert some influence. Caloric restriction is most effective when maintained during both initiation and promotion, but if limited to one of these phases, restriction during promotion appears to be the more effective modality. The types of tumor that have been studied include spontaneous mammary and lung tumors as well as tumors induced by organ-specific carcinogens or irradiation with ultraviolet light. Numerous investigators have studied the effects of fat, and a diet low in calories but high in fat is generally significantly more effective in inhibiting carcinogenesis than is a diet high in calories but low in fat. Mice fed high fat, low calorie diets exhibited 48% fewer chemically induced skin tumors and 61% fewer tumors induced by ultraviolet irradiation than did mice fed low fat, high calorie diets. Mice fed a diet containing 2% fat exhibited a 66% incidence of skin tumors, whereas mice fed an isocaloric diet containing 61% fat showed a 78% incidence. Rats whose diet was restricted in calories by 40% exhibited no mammary tumors (coconut oil as primary dietary fat) or 75% fewer tumors (corn oil as dietary fat) compared to ad libitum-fed controls; they also exhibited 47% fewer colonic tumors. The mechanism by which caloric restriction exerts its tumor-inhibiting effects remains to be elucidated.

  6. Apuntes de Transmisión del Calor

    OpenAIRE

    Martín Domingo, Agustín

    2016-01-01

    Esta publicacion está basada en unos apuntes para la parte de Transmisión del Calor de las asignaturas de la ETSAM. Sin embargo, con el tiempo se ha añadido otro material extra que excede ampliamente el contenido del curso.

  7. Dal calore all'entropia una introduzione alla termodinamica

    CERN Document Server

    Vicentini Missoni, Matilde

    1992-01-01

    Panta rei : processi ed equilibrio ; l'universo termodinamico : l'aspetto processuale ; il punto di vista dei processi come bilancio tra proprietà dell'equilibrio ; il fluire dell'energia ; automobili, frigoriferi e pompe di calore : informazioni tecnologiche ; e allora ? l'entropia ; la termostatica come teoria assiomatica ; la termodinamica dei processi.

  8. Apuntes de Transmisión del Calor

    OpenAIRE

    2013-01-01

    Esta publicacion está basada en unos apuntes para la parte de Transmisión del Calor de las asignaturas de la ETSAM. Sin embargo, con el tiempo se ha añadido otro material extra que excede ampliamente el contenido del curso.

  9. Cupula dynamics under caloric stimulation of the semicircular canal

    Science.gov (United States)

    Kondrachuk, A. V.; Sirenko, S. P.

    Caloric stimulation of the semicircular canal SC is widely applied in studies of vestibular impairments Barany 1906 suggested that caloric response of SC results from mechanism of endolymph convection due to density changes of endolymph and therefore depends on the action of gravity forces However the Skylab experiments 1983 showed that the caloric reaction of SC can take place even under microgravity The studies of Scherer Clarke 1985 Harada Ariki 1985 Baumgarten et al 1985 considered the thermal expansion of endolymph to be a concurrent mechanism The model of caloric response based on the buoyancy force due to density change in the endolymph induced by thermal stimulation was proposed by Gentine et al 1990 1991 It should be noted that the first qualitative model that took into account the effect of endolymph thermal expansion under local heating to analyze the properties of primary afferents was proposed by Gusev Orlov 1977 However these models failed to answer the question which of the mentioned effects will be dominant under certain conditions The purpose of present study was to account for the expansion and convection of endolymph and to determine under which conditions one mechanism dominates over the other The consideration is based on the following model of SC Kondrachuk Sirenko 1990 an isolated torus filled by a compressible viscous Newton liquid endolymph the torus interior is plugged by an elastic body cupula the cupula surface in contact with endolymph is supposed to be stretched along the

  10. The caloric vestibular nystagmus during short lasting microgravity

    Science.gov (United States)

    Oosterveld, W. J.; de Jong, H. A. A.; Kortschot, H. W.

    In human subjects the caloric vestibular test was conducted during parabolic flight. The ear irrigation was performed from 35 secs. till 5 secs. before the onset of microgravity. Nystagmography covered a 10-minutes period, including three parabolic manoeuvres of the aircraft. a. The slow phase velocity (SPV) of the caloric nystagmus increased proportionally with the value of the g-force. Introduction of microgravity induced an exponential decrease of the SPV decay. b. The nystagmus disappeared completely in microgravity, but SPV decay showed a specific time constant. c. The averaged time constant values of the caloric nystagmus SPV decay after sudden onset of microgravity and the averaged time constant of the SPV decay following a sudden stop after sustained rotation during 0-g appeared to be on the same level (10.2 s. and 10.6 s.). d. These two averaged time constant values obtained during shortlasting microgravity proved to be on a lower level than those time constants (15.5 secs.; 15.9 secs.) found in ground-based conditions. e. Because of the similarities in the characteristics of both SPV decay's and their accompanying time constants, a common working mechanism of cupular stimulation is likely. Most probably a fluid movement (or pressure) provokes a cupula deflexion followed by a cupula reflexion, either caused by a sudden stop after a sustained rotation or by a sudden onset of microgravity after g-load calorization. The present results support the Bárány convection theory with regard the endolymph stimulatory properties following the caloric test.

  11. Otimização térmica e econômica de bomba de calor para aquecimento de água, utilizando programação quadrática sequencial e simulação através do método de substituição Newton Raphson

    OpenAIRE

    Obed Alexander Córdova Lobatón

    2011-01-01

    Resumo: O trabalho apresenta metodologias computacionais de otimização e simulação para o desenvolvimento do projeto de um sistema de bomba de calor para aquecimento de água em prédios residenciais, especialmente para uso em banho na região de Campinas. O sistema bomba de calor foi simulado focando o estudo nos trocadores de calor (evaporador e condensador). Cada componente foi otimizado mediante uma análise térmica e econômica que permitiu reduzir custos de investimento e de operação através...

  12. Transient Astrophysics Probe

    Science.gov (United States)

    Camp, Jordan

    2017-08-01

    Transient Astrophysics Probe (TAP), selected by NASA for a funded Concept Study, is a wide-field high-energy transient mission proposed for flight starting in the late 2020s. TAP’s main science goals, called out as Frontier Discovery areas in the 2010 Decadal Survey, are time-domain astrophysics and counterparts of gravitational wave (GW) detections. The mission instruments include unique imaging soft X-ray optics that allow ~500 deg2 FoV in each of four separate modules; a high sensitivity, 1 deg2 FoV soft X-ray telescope based on single crystal silicon optics; a passively cooled, 1 deg2 FoV Infrared telescope with bandpass 0.6-3 micron; and a set of ~8 small NaI gamma-ray detectors. TAP will observe many events per year of X-ray transients related to compact objects, including tidal disruptions of stars, supernova shock breakouts, neutron star bursts and superbursts, and high redshift Gamma-Ray Bursts. Perhaps most exciting is TAP’s capability to observe X-ray and IR counterparts of GWs involving stellar mass black holes detected by LIGO/Virgo, and possibly X-ray counterparts of GWs from supermassive black holes, detected by LISA and Pulsar Timing Arrays.

  13. The effect of prolonged physical activity performed during extreme caloric deprivation on cardiac function.

    Directory of Open Access Journals (Sweden)

    David Planer

    Full Text Available BACKGROUND: Endurance exercise may induce transient cardiac dysfunction. Data regarding the effect of caloric restriction on cardiac function is limited. We studied the effect of physical activity performed during extreme caloric deprivation on cardiac function. METHODS: Thirty-nine healthy male soldiers (mean age 20 ± 0.3 years were studied during a field training exercise lasted 85-103 hours, with negligible food intake and unlimited water supply. Anthropometric measurements, echocardiographic examinations and blood and urine tests were performed before and after the training exercise. RESULTS: Baseline VO(2 max was 59 ± 5.5 ml/kg/min. Participants' mean weight reduction was 5.7 ± 0.9 kg. There was an increase in plasma urea (11.6 ± 2.6 to 15.8 ± 3.8 mmol/L, p<0.001 and urine osmolarity (692 ± 212 to 1094 ± 140 mmol/kg, p<0.001 and a decrease in sodium levels (140.5 ± 1.0 to 136.6 ± 2.1 mmol/L, p<0.001 at the end of the study. Significant alterations in diastolic parameters included a decrease in mitral E wave (93.6 to 83.5 cm/s; p = 0.003, without change in E/A and E/E' ratios, and an increase in iso-volumic relaxation time (73.9 to 82.9 ms, p = 0.006. There was no change in left or right ventricular systolic function, or pulmonary arterial pressure. Brain natriuretic peptide (BNP levels were significantly reduced post-training (median 9 to 0 pg/ml, p<0.001. There was no elevation in Troponin T or CRP levels. On multivariate analysis, BNP reduction correlated with sodium levels and weight reduction (R = 0.8, p<0.001. CONCLUSIONS: Exposure to prolonged physical activity performed under caloric deprivation resulted in minor alterations of left ventricular diastolic function. BNP levels were significantly reduced due to negative water and sodium balance.

  14. Modelo descritivo do fluxo de calor em soldagem a arco visando o conceito de calor imposto efetivo Descriptive model of the heat flow in arc welding targeting the concept of effective heat input

    Directory of Open Access Journals (Sweden)

    Américo Scotti

    2012-06-01

    Full Text Available O objetivo do presente trabalho é propor um modelo global para descrever o fluxo de calor em soldagem a arco, visando o entendimento dos fenômenos relacionados com o fluxo de calor. A tentativa é suprir uma lacuna do conhecimento gerado entre a aplicação de modelos analíticos simplificados (não totalmente realistas e de modelos numéricos (que mascaram a visão física dos fenômenos. Inicia-se propondo uma descrição mais física para a razão da queda de tensão num arco, baseada na geração e perda de calor para se manter o equilíbrio da desionização e reionização, em contraste com a abordagem em que o arco é comparável a um resistor elétrico. Em seguida, se propõe um modelo descritivo da subsistência térmica de um arco, para qualificar as formas de transferência de calor do arco para a chapa. Um segundo modelo descritivo é então proposto para explicar como o calor entra, difunde e sai da chapa durante a soldagem. Finalmente, é discutido como a aplicação destes dois modelos de forma global permite entender que nem todo o fluxo de calor do arco para a chapa vai afetar a velocidade de resfriamento nas regiões do material aquecidas. Culmina-se com a proposta do emprego do termo Calor Imposto Efetivo como meio de evidenciar o parâmetro de calor de importância a ser determinado em soldagem.The objective of the present paper is to propose a global model for describing heat flow in arc welding, aiming the understanding of the phenomena involved. The attempt is to fill out a gap of knowledge which has been generated between the application of simplified analytical models (not totally realistic and numerical models (that disguises the physics of the phenomena. Initially, a physic-oriented description of the reasons for welding arc voltage drop is presented. This description is based on the heat generation and its losses to maintain the balance between deionization and reionization, in contrast to the approach that the arc

  15. Caloric values for young sprouts of nine hardwood species

    Energy Technology Data Exchange (ETDEWEB)

    Neenan, M. (An Foras Taluntais, Oak Park, Carlow, Ireland); Steinbeck, K.

    1979-09-01

    Caloric content, specific gravity, and ash content of 6- to 15-year-old sprouts of nine hardwood species were determined in midsummer. Energy values for wood, bark, first order branches, twigs, and leaves were determined with an adiabatic bomb calorimeter. The values found for coppice material averaged 4791 cal/g and were comparable to published values for older wood. Intraspecific differences among tissues were greater than the relatively small but significant differences among species. Differences in yield potential are therefore likely to outweigh variations in caloric content among species where total energy production per unit of land area is concerned. Ash content varied from 0.65 percent for wood to 5.88 percent for bark.

  16. DESARROLLOS INSTRUMENTALES EN MICROCALORIMETRIA DE CONDUCCIÓN DE CALOR

    Directory of Open Access Journals (Sweden)

    Liliana Giraldo G.

    2010-09-01

    Full Text Available Se presentan aspectos generales de la microcalorimetría de conducción de calor. Se describe el diseño y la operación de microcalorímetros de conducción de calor estático y de flujo construidos en este laboratorio, los cuales fueron calibrados eléctrica y químicamente. Estos equipos se emplean en la caracterización de sólidos porosos por la técnica de calorimetría de inmersión y en la determinación de entalpias de transferencia de solutos; su uso se ilustra con algunos resultados típicos. Se mencionan además otras aplicaciones que se dan actualmente a estos aparatos.

  17. Caloric Effects in Methylammonium Lead Iodide from Molecular Dynamics Simulations

    OpenAIRE

    Liu, Shi; Cohen, Ronald E.

    2016-01-01

    Organic-inorganic hybrid perovskite architecture could serve as a robust platform for materials design to realize functionalities beyond photovoltaic applications. We explore caloric effects in organometal halide perovskites, taking methylammonium lead iodide (MAPbI$_3$) as an example, using all-atom molecular dynamics simulations with a first-principles based interatomic potential. The adiabatic thermal change is estimated directly by introducing different driving fields in the simulations. ...

  18. Household Food Consumption, Individual Caloric Intake and Obesity in France

    OpenAIRE

    Bonnet, Céline; Dubois, Pierre; Orozco, Valérie

    2009-01-01

    We show how to use a long period of observation of all food purchases at the household level to infer the profile of average individual caloric intakes according to the gender, age and the body mass index of household members. Using data from France, we apply this method to analyze the relationship between obesity and individual food consumption. The results show that obese or overweight individuals do absorb more calories at all ages but with differences that vary across gender and ages and ...

  19. An In Vivo Magnetic Resonance Spectroscopy Study of the Effects of Caloric and Non-Caloric Sweeteners on Liver Lipid Metabolism in Rats

    NARCIS (Netherlands)

    Janssens, Sharon; Ciapaite, Jolita; Wolters, Justina C.; van Riel, Natal A.; Nicolay, Klaas; Prompers, Jeanine J.

    2017-01-01

    We aimed to elucidate the effects of caloric and non-caloric sweeteners on liver lipid metabolism in rats using in vivo magnetic resonance spectroscopy (MRS) and to determine their roles in the development of liver steatosis. Wistar rats received normal chow and either normal drinking water, or

  20. Quantificação da ilha de calor de curitiba considerando aspectos de estabilidade atmosférica

    Directory of Open Access Journals (Sweden)

    Eduardo Krüger

    2015-12-01

    Full Text Available RESUMO A relação entre crescimento urbano e o surgimento de ilhas de calor urbanas, ou seja, diferenças climáticas entre a área urbana e as áreas rurais no entorno, é demonstrada por diversos autores e em diferentes regiões climáticas. Em Curitiba, a população saltou de aproximadamente 600.000 habitantes para um milhão e meio em três décadas. O objetivo do presente trabalho é propor uma metodologia de análise da ilha de calor urbana de Curitiba (25º25'40"S, 49º16'23"W, 934m acima do nível do mar. A cidade está localizada em região de clima subtropical de altitude; o monitoramento climático foi conduzido segundo uma série anual, entre dezembro de 2011 e fevereiro de 2013, utilizando um par de estações meteorológicas dentro e fora (perifericamente da mancha urbana de Curitiba. De modo a minimizar possíveis influências atmosféricas na análise, foi feita a classificação dos dias de medição por classes de estabilidade atmosférica segundo o método de Pasquill-Gifford-Turner (PGT, procedendo-se à análise para dias com maior estabilidade atmosférica. Como complemento à análise, adota-se um modelo de conforto desenvolvido para Curitiba a partir de uma extensa pesquisa de sensação e percepção térmicas em espaços abertos, de modo a verificar o efeito integrado das diversas variáveis climáticas em termos de percentuais de horas em frio, conforto e calor e suas variações dentro e fora da área urbana. Em Curitiba, a ilha de calor urbana pode ser benéfica durante o inverno, porém trazendo consequências em termos de excesso de calor em ambientes internos no verão.

  1. Correlation between caloric and ocular vestibular evoked myogenic potential test results.

    Science.gov (United States)

    Huang, Chi-Hsuan; Wang, Shou-Jen; Young, Yi-Ho

    2012-02-01

    The ocular vestibular evoked myogenic potential (o-VEMP) test results correlate significantly with caloric test results for patients with acoustic neuroma (AN), but not for patients with Meniere's disease (MD), indicating that the o-VEMP test may replace the caloric test for evaluating the vestibular nerve from which the AN arises. Conversely, the caloric, o-VEMP, and cervical VEMP (c-VEMP) tests should be performed to map lesion sites in the vestibular labyrinth. This study performed caloric, o-VEMP, and c-VEMP tests on patients with central and peripheral vestibular disorders to investigate their relationships. In all, 66 patients comprising 16 with unilateral AN and 50 with unilateral definite MD were enrolled. All patients underwent caloric, o-VEMP, and c-VEMP tests. In the AN group, the caloric test identified canal paresis and caloric areflexia in 10 ears, while the o-VEMP and c-VEMP tests identified abnormal (absent or delayed) responses in 12 and 11 ears, respectively. A significant correlation existed between caloric and o-VEMP test results, but not between caloric and c-VEMP test results, or between o-VEMP and c-VEMP test results. For the MD group, abnormal caloric, o-VEMP, and c-VEMP test results were obtained for 24%, 44%, and 38% of hydropic ears, respectively. No correlation existed between any two test results.

  2. Aspectos da adaptalidade ao calor de ovinos da raça Santa Inês no Agreste de Pernambuco.

    OpenAIRE

    2009-01-01

    Os objetivos deste trabalho foram verificar a influência da cor do pelame na tolerância ao calor, consumo a pasto e ganho de peso de ovinos da raça Santa Inês de três diferentes cores de pelame (branca, castanha e preta). O experimento foi conduzido de janeiro a março de 2008 na Fazenda Riachão, localizada no município de Sairé, região agreste de Pernambuco. Os parâmetros fisiológicos temperatura retal (TR), frequência respiratória (FR), temperatura de pele (TPL) e temperatura da superfíci...

  3. The Lexicocalorimeter: Gauging public health through caloric input and output on social media

    CERN Document Server

    Alajajian, S E; Reagan, A J; Alajajian, S C; Frank, M R; Mitchell, L; Lahne, J; Danforth, C M; Dodds, P S

    2015-01-01

    We propose and develop a Lexicocalorimeter: an online, interactive instrument for measuring the "caloric content" of social media and other large-scale texts. We do so by constructing extensive yet improvable tables of food and activity related phrases, and respectively assigning them with sourced estimates of caloric intake and expenditure. We show that for Twitter, our naive measures of "caloric input", "caloric output", and the ratio of these measures---"caloric balance"---are all strong correlates with health and well-being demographics for the contiguous United States. Our caloric balance measure outperforms both its constituent quantities, is tunable to specific demographic measures such as diabetes rates, provides a real-time signal reflecting a population's health, and has the potential to be used alongside traditional survey data in the development of public policy and collective self-awareness. Because our Lexicocalorimeter is a linear superposition of principled phrase scores, we also show we can m...

  4. Transient Ischemic Attack

    Medline Plus

    Full Text Available Transient Ischemic Attack TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood ... The only difference between a stroke and TIA is that with TIA the blockage is transient (temporary). ...

  5. Interplay between various degrees of freedom in determining the aspect of the caloric curve

    CERN Document Server

    Raduta, A H

    1999-01-01

    A sharp microcanonical model is used to investigate the primary decay nuclear caloric curve. A wide plateau of the caloric curve corresponding to a temperature of around 5 MeV, sign of liquid-gas phase transition, is evidenced for three sample nuclei. The results are resembling the experimental data of Pochodzalla et al. [Phys. Rev. Lett. 75 (1995) 1040]. Calculated He-Li temperatures manifest a similar behavior. Correlations between different parts of the caloric curves and the energy amounts deposited in the available degrees are discussed. The extent to which the existent degrees of freedom are contributing to the shape of the caloric curve is commented.

  6. La isla de calor estival en Temuco, Chile

    Directory of Open Access Journals (Sweden)

    Alicia Capelli de Steffens

    2001-01-01

    Full Text Available Temuco es una ciudad localizada en el centro sur de Chile (38º 45’ S y 72º 40’ W. Morfológicamente, el sitio de la ciudad corresponde a las terrazas fluviales del río Cautín que se desarrollan en forma encajonada entre los cerros Ñielol (350 m y Conunhueno (360 m. Esta ciudad se ha desarrollado rápidamente en las últimas décadas, por lo tanto es necesario conocer el efecto antrópico en la misma. Para evaluar parte de ese efecto se analiza la isla de calor urbana estival en la ciudad de Temuco, Chile. Se efectuaron mediciones de temperatura del aire y humedad a través de la ciudad para determinar la forma y la intensidad de la isla de calor urbano. Se utilizaron estaciones móviles e información de una estación meteorológica fija. La ciudad presenta un comportamiento térmico diferente a lo largo del día. Durante el día genera una isla de calor que responde en líneas generales al modelo ideal de calentamiento urbano. La intensidad de la isla calórica (∆Tu-r fue 6.3ºC y 1.2ºC durante el día y la noche, respectivamente. La influencia de los cerros que limitan la ciudad es importante. El estudio confirma la idea que el clima urbano de una ciudad es un mosaico de microclimas que interactuan continuamente.

  7. A crise do socialismo analisada no calor da hora

    Directory of Open Access Journals (Sweden)

    Reginaldo Benedito Dias

    2009-11-01

    Full Text Available O presente artigo demonstra como os acontecimentos que levaram à crise e desintegração dos países do bloco soviético foram analisados no calor dos acontecimentos, tomando como parâmetro os livros "Nós, o povo" e "A desintegração do monolito", selecionados por causa das diferentes perspectivas metodológicas e ideológicas que representam.  

  8. Transient global amnesia mimics: Transient epileptic amnesia

    Directory of Open Access Journals (Sweden)

    Nicolas Nicastro

    2014-01-01

    Full Text Available We describe the case of a 79-year-old patient referred for suspected transient global amnesia, after an episode of anterograde amnesia which lasted 90 min. An EEG, performed after the episode, showed bilateral temporal electrographic seizures, orienting the diagnosis toward a transient epileptic amnesia. Transient epileptic amnesia is defined by temporal lobe epilepsy characterized by recurrent transient amnestic episodes of 30–90 min in duration, sometimes associated with olfactory hallucinations or oral automatisms. Response to antiepileptic drugs is excellent. We would like to raise awareness toward this epileptic amnesia when facing atypical or recurrent transient amnestic episodes.

  9. ISOTERMAS E CALOR ISOSTÉRICO DE ADSORÇÃO DA ÁGUA DO AMIDO DE QUINOA

    Directory of Open Access Journals (Sweden)

    AUGUSTO PUMACAHUA RAMOS

    2017-07-01

    Full Text Available A quinoa possui mais de 60% de amido, sendo uma alternativa de extração e comercialização. Para isto é necessário conhecer o comportamento do amido frente à temperatura e umidade relativa do ar. O objetivo desta pesquisa foi avaliar as isotermas de adsorção do amido de quinoa em cinco temperaturas (20, 30, 40, 50 e 60ºC e dez atividades de água (0,036 a 0,907. Os pontos experimentais foram ajustados aos modelos matemáticos GAB, Oswin, Henderson, Peleg e Ferro-Foltan. Foram determinadas as energias de ativação da adsorção da água pelas constantes do modelo GAB e o calor isostérico pelo modelo de Peleg. As isotermas mostraram ser do tipo II na classificação de Brunauer. Os teores de água da monocamada (Xm determinados pelo modelo de GAB variaram de 7,90% a 10,38% base seca (b.s. para temperaturas de 60 e 20°C e as energias de ativação obtidas pelas constantes Xm, C e K do modelo de GAB foram de 300; 160 e 6 kJ/kg, respectivamente. O calor isostérico de adsorção foi de 3732 kJ/kg para umidade de equilíbrio de 0,5% b.s. e diminuiu com o aumento da umidade até valor próximo ao calor latente de vaporização da água pura a 36% b.s. As propriedades determinadas são características de amidos com elevado teor de amilopectina.

  10. Balanço eletrolítico e redução da proteína bruta da ração sobre parâmetros fisiológicos e sanguíneos de frangos de corte no calor - DOI: 10.4025/actascianimsci.v31i3.4792 Electrolyte balance and crude protein reduction in physiologic and blood parameters of broiler chickens in heat - DOI: 10.4025/actascianimsci.v31i3.4792

    Directory of Open Access Journals (Sweden)

    Rita da Trindade Ribeiro Nobre Soares

    2009-09-01

    Full Text Available Um experimento foi conduzido, objetivando-se avaliar o efeito do balanço eletrolítico (BER e a redução da proteína bruta (PB da ração sobre a frequência respiratória, temperatura cloacal, concentrações de Na+, K+, Cl- e ácido úrico em frangos de corte. Foram utilizados 800 pintos de corte, machos da linhagem Cobb, alojados em 20 boxes, distribuídos em delineamento inteiramente casualizado com quatro tratamentos, cinco repetições e 40 aves por unidade experimental. Os tratamentos foram: T1 - ração basal; T2 - ração corrigida para BER de 250 mEq kg-1; T3 - ração com redução de PB, sem correção de BER; T4 - ração com redução de PB corrigida para BER de 250 mEq kg-1. As condições ambientais evidenciaram que os animais estavam em estresse por calor. As aves que receberam rações com correção do BER apresentaram menores valores (p 0,05 da temperatura cloacal no período total. A redução da PB diminuiu (p An experiment was carried with the objective of evaluating the effect of diet electrolyte balance (DEB and crude protein (CP reduction on respiratory rate, cloacal temperature and concentrations of Na+, K+, Cl- and uric acid of broiler chickens. Eight-hundred male Cobb broiler chickens were randomly allocated in 20 boxes, with four treatments and five replicates of 40 birds per experimental unity. The treatments were: T1 - basal diet; T2 - diet adjustment until DEB = 250 mEq kg-1; T3 - diet with reduction of CP and without adjustment of DEB; T4 - diet with reduction of CP and adjustment of DEB to 250 mEq kg-1. The thermal environment was not favorable during the experimental period. The birds that received diets with correction of electrolyte balance showed low values (p 0.05. Reduction of crude protein decreased (p 0.05 at 42 days. The supplementation with electrolytes improved homeostasis of the broilers in heat stress conditions.

  11. Lifelong caloric restriction increases working memory in mice.

    Directory of Open Access Journals (Sweden)

    Angela Kuhla

    Full Text Available Caloric restriction (CR is argued to positively affect general health, longevity and the normally occurring age-related reduction of cognition. This issue is well examined, but most studies investigated the effect of short-term periods of CR. Herein, 4 weeks old female mice were fed caloric restricted for 4, 20 and especially for 74 weeks. CR mice received 60% of food eaten by their ad libitum (AL fed littermates, and all age-matched groups were behaviorally analyzed. The motor coordination, which was tested by rotarod/accelerod, decreased age-related, but was not influenced by the different periods of CR. In contrast, the age-related impairment of spontaneous locomotor activity and anxiety, both being evaluated by open field and by elevated plus maze test, was found aggravated by a lifelong CR. Measurement of cognitive performance with morris water maze showed that the working memory decreased age-related in AL mice, while a lifelong CR caused a better cognitive performance and resulted in a significantly better spatial memory upon 74 weeks CR feeding. However, a late-onset CR feeding in 66 weeks old mice did not ameliorate the working memory. Therefore, a lifelong CR seems to be necessary to improve working memory.

  12. Lifelong caloric restriction increases working memory in mice.

    Science.gov (United States)

    Kuhla, Angela; Lange, Sophie; Holzmann, Carsten; Maass, Fabian; Petersen, Jana; Vollmar, Brigitte; Wree, Andreas

    2013-01-01

    Caloric restriction (CR) is argued to positively affect general health, longevity and the normally occurring age-related reduction of cognition. This issue is well examined, but most studies investigated the effect of short-term periods of CR. Herein, 4 weeks old female mice were fed caloric restricted for 4, 20 and especially for 74 weeks. CR mice received 60% of food eaten by their ad libitum (AL) fed littermates, and all age-matched groups were behaviorally analyzed. The motor coordination, which was tested by rotarod/accelerod, decreased age-related, but was not influenced by the different periods of CR. In contrast, the age-related impairment of spontaneous locomotor activity and anxiety, both being evaluated by open field and by elevated plus maze test, was found aggravated by a lifelong CR. Measurement of cognitive performance with morris water maze showed that the working memory decreased age-related in AL mice, while a lifelong CR caused a better cognitive performance and resulted in a significantly better spatial memory upon 74 weeks CR feeding. However, a late-onset CR feeding in 66 weeks old mice did not ameliorate the working memory. Therefore, a lifelong CR seems to be necessary to improve working memory.

  13. Isla de calor en Toluca, México

    Directory of Open Access Journals (Sweden)

    Carlos Constantino Morales Méndez

    2007-01-01

    Full Text Available El clima de la ciudad de Toluca y del mundo ha sido modificado como consecuencia del crecimiento de su población y el aumento de las dimensiones de su distribución territorial. Las variaciones atmosféricas son más acusadas entre los espacios urbanos y rurales a medida que las ciudades son más grandes y su mancha urbana es más extensa,así como de la reducción de la vegetación, el aumento en la calefacción en casas y edificios y por la contaminación del aire. Para identificar los espacios con calor más intenso por la infraestructura urbana, se propone una metodología que consiste en la determinación de los valores de temperatura que se registraron en dos días típicos de invierno y verano, durante el día y la noche,mostrando la distribución de la isla de calor en la zona de estudio, a partir de los datos delas estaciones de la Red Automática de Monitoreo Ambiental (RAMA. Asimismo, se considera el comportamiento y variación de algunas variables atmosféricas como humedad relativa, precipitación y viento, para mostrar su comportamiento relativamente anómalo en la zona urbana.

  14. High monetary reward rates and caloric rewards decrease temporal persistence

    Science.gov (United States)

    Bode, Stefan; Murawski, Carsten

    2017-01-01

    Temporal persistence refers to an individual's capacity to wait for future rewards, while forgoing possible alternatives. This requires a trade-off between the potential value of delayed rewards and opportunity costs, and is relevant to many real-world decisions, such as dieting. Theoretical models have previously suggested that high monetary reward rates, or positive energy balance, may result in decreased temporal persistence. In our study, 50 fasted participants engaged in a temporal persistence task, incentivised with monetary rewards. In alternating blocks of this task, rewards were delivered at delays drawn randomly from distributions with either a lower or higher maximum reward rate. During some blocks participants received either a caloric drink or water. We used survival analysis to estimate participants' probability of quitting conditional on the delay distribution and the consumed liquid. Participants had a higher probability of quitting in blocks with the higher reward rate. Furthermore, participants who consumed the caloric drink had a higher probability of quitting than those who consumed water. Our results support the predictions from the theoretical models, and importantly, suggest that both higher monetary reward rates and physiologically relevant rewards can decrease temporal persistence, which is a crucial determinant for survival in many species. PMID:28228517

  15. Efeitos da termoterapia induzida pela água na próstata: estudo experimental em cães

    OpenAIRE

    Gobbo, Carlos Alberto Monte [UNESP

    2001-01-01

    Nos últimos anos, foram desenvolvidas diversas modalidades alternativas para o tratamento da HPB. Entre elas, incluem-se terapêuticas medicamentosas e aquelas que se convencionou denominar de minimamente invasivas. Estas últimas fundamentam-se na aplicação de calor (hipertermia e termoterapia), de laser, de radiofreqüência, de ultrasom, na dilatação uretral com balões, na colocação de endopróteses uretrais e na incisão transuretral da próstata. Entre os métodos que utilizam o calor para trata...

  16. Distúrbios causados pelo frio e pelo calor durante corridas de longa distância

    Directory of Open Access Journals (Sweden)

    1999-06-01

    Full Text Available Muitos corredores amadores e de elite participam todos os anos de corridas de longa distância. Quando estes eventos ocorrem em temperaturas altas ou baixas, aumenta o risco de distúrbios térmicos. Contudo, a hipertermia induzida pelo exercício, a hipotermia, a desidratação e outros problemas relacionados podem ser minimizados através de esclarecimentos e um preparo antes do evento. Este documento fornece recomendações para o diretor médico e outras autoridades da organização das corridas nas seguintes áreas: planejamento, profissionais envolvidos na organização, instalações, suprimentos, equipamento e comunicação; fornecimento de esclarecimentos aos participantes; avaliação do estresse térmico; fornecimento de líquidos; e prevenção de questões legais em potencial. Este posicionamento oficial também descreve as condições predisponentes, as formas de diagnóstico e o tratamento dos quatro distúrbios ambientais mais comuns: exaustão pelo calor, colapso pelo calor, hipotermia e congelamento de extremidades. Os objetivos deste documento são: 1 Educar os organizadores e os participantes de corridas de longa distância a respeito das formas mais comuns de distúrbios térmicos incluindo as condições predisponentes, sinais de alerta, suscetibilidade e a redução de sua incidência; 2 Alertar os organizadores sobre as suas responsabilidades civis em potencial no que concerne à segurança do evento e à prevenção de lesões; 3 Recomendar que os organizadores consultem arquivos locais de meteorologia e planejem eventos em horas que provavelmente causem menos estresse térmico de modo a minimizar os efeitos deletérios sobre os participantes; 4 Estimular os organizadores a alertar os participantes sobre o estresse térmico no dia da corrida e as suas implicações no que tange aos distúrbios causados pelo frio e pelo calor; 5 Informar os organizadores sobre as ações preventivas que podem reduzir a incidência dos

  17. Current interruption transients calculation

    CERN Document Server

    Peelo, David F

    2014-01-01

    Provides an original, detailed and practical description of current interruption transients, origins, and the circuits involved, and how they can be calculated Current Interruption Transients Calculationis a comprehensive resource for the understanding, calculation and analysis of the transient recovery voltages (TRVs) and related re-ignition or re-striking transients associated with fault current interruption and the switching of inductive and capacitive load currents in circuits. This book provides an original, detailed and practical description of current interruption transients, origins,

  18. A randomized control trial for reduction of caloric and non-caloric sweetened beverages in young adults: effects in weight, body composition and blood pressure.

    Science.gov (United States)

    Vázquez-Durán, Marisela; Orea-Tejeda, Arturo; Castillo-Martínez, Lilia; Cano-García, Ángeles; Téllez-Olvera, Laura; Keirns-Davis, Candace

    2016-11-29

    Recently has been documented that the consumption of sweetened non-caloric beverages has increased as an option to weight control, however randomized control trials have demonstrated a modest weight loss. To evaluate the effect of reducing consumption of beverage with caloric and non-caloric sweeteners on weight, body composition and blood pressure in young Mexican adults. In an experimental study 148 nursing students were randomly assigned to one of 3 groups: 1) no sweetened beverages were permitted, only plain water, tea or coffee without sugar; 2) consumption of beverages with non-caloric sweeteners was allowed; and 3) no restriction of sweetened beverages was imposed. All groups were given individualized isocaloric diets monitored by a 24-hour record of consumption and food frequency questionnaire and blood pressure, weight, waist circumference and body composition by tetrapolar bioelectric impedance were taken at the beginning of the study and three and six months later. Differences between groups were found in body mass index at 3 months that decrease in group 1 and 2 and increase in group 3 (-1.75 vs.-0.61 vs.0.54% of change, p consumption (-62.0 vs.-54.61 vs.11.08% of change, p consumption of both caloric and non-caloric sweetened beverages contributes to signifi cant body mass index loss and waist circumference.

  19. Estimulação calórica a ar em mastoidectomias abertas unilaterais Air caloric test in canal wall down mastoidectomy

    Directory of Open Access Journals (Sweden)

    Lucia Kazuko Nishino

    2012-06-01

    Full Text Available Poucos trabalhos desde a década de 70 foram realizados a fim de elucidar a prova calórica em alterações da orelha média, apesar de inúmeras controvérsias que este exame pode trazer em estruturas anatômicas tão distintas. Na mastoidectomia radical, estes estudos são mais escassos. OBJETIVO: Este estudo teve como objetivo analisar os achados da estimulação calórica a ar em indivíduos com mastoidectomia radical unilateral sem queixas de tontura. MATERIAL E MÉTODO: Estudo prospectivo, realização da estimulação calórica a ar em 36 indivíduos sem queixas vestibulares, sendo 21 com cirurgia de mastoidectomia aberta unilateral e 15 sem nenhuma alteração na orelha média ou externa. RESULTADOS: 80,95% dos indivíduos apresentaram respostas assimétricas na prova calórica frias, sendo as respostas maiores do lado da mastoidectomia aberta. Em 72,73%, o mesmo efeito ocorreu com a prova calórica quente. Na análise das quatro estimulações, encontrou-se assimetria das provas quente e frias em 81,82% dos casos. Em 47,61%, foi encontrada estimulação paradoxal da prova calórica quente. CONCLUSÃO:As respostas nistágmicas do lado da mastoidectomia aberta foram maiores se comparadas com o lado saudável. A estimulação paradoxal da prova calórica quente foi um achado frequente. Não foram encontradas respostas hipofuncionantes.Since the 1970s, few studies have been conducted to elucidate the use of caloric tests on middle ear disorders, despite the many controversies that this test may produce in anatomical structures that are so distinct. In cases of mastoidectomy, such studies are even rarer. OBJECTIVE: This study aims to analyze the findings from air caloric stimulation done in individuals submitted to unilateral radical mastoidectomy without complaints of dizziness. MATERIALS AND METHOD: Thirty-six individuals without vestibular complaints were enrolled in this prospective study. Air caloric stimulation was offered to all

  20. Isla de calor y ocupación espacial urbana en San Juan, Argentina: análisis evolutivo. Island heat effect and spatial urban occupancy in San Juan, Argentina: evolution analysis Ilha de calor e ocupação do espaço urbano em San Juán, Argentina: análise evolutiva

    Directory of Open Access Journals (Sweden)

    Mario Cúnsulo

    2011-06-01

    Full Text Available Resumen:En este artículo se presentan resultados finales de un proyecto de investigación bianual (2009-2010, denominado Variación histórica y espacial de la isla de calor urbana en zona árida, financiado por la Universidad Nacional de San Juan, Argentina. Su objetivo principal es determinar la progresiva modificación de la isla de calor urbana en un periodo de quince años (1995-2010 y la correlación de esta con la ocupación del área urbana del Gran San Juan (GSJ, localizada en la diagonal árida de Sudamérica. Los resultados obtenidos demuestran la interrelación entre la ocupación urbana y la espacialización de la isla de calor en la ciudad.Abstract:In this paper, final result of a bi-annual project (2009-2010 called Historic and spatial variation of the urban island heat effect in an arid zone –financed by Universidad Nacional de San Juan, Argentina –are presented. Its main aim is determining the progressive changing of urban island heat effect during a fifteen year period (1995-2010 and its correlationwith the occupancy of Great San Juan (GSJ urban area, located in South America’s arid diagonal. Results show the interrelationship between urban occupancy and the spread of island heat effect in the city.Resumo:Este artigo apresenta resultados finais do projeto de pesquisa de dois anos (2009-2010, chamado A variação histórica e espacial da ilha de calor urbana em uma zona árida, financiado pela Universidad Nacional de San Juán, Argentina. Seu principal objetivo é determinar a modificação progressiva da ilha de calor urbana por um período de 15 anos (1995-2010 e a correlação desta com a ocupação da área urbana da Gran San Juan (GSJ, localizada na diagonal árida de América do Sul. Os resultados obtidos demonstram a relação entre ocupação urbana e espacialização da ilha de calor na cidade.

  1. Caloric Restriction Promotes Structural and Metabolic Changes in the Skin

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Forni

    2017-09-01

    Full Text Available Caloric restriction (CR is the most effective intervention known to enhance lifespan, but its effect on the skin is poorly understood. Here, we show that CR mice display fur coat remodeling associated with an expansion of the hair follicle stem cell (HFSC pool. We also find that the dermal adipocyte depot (dWAT is underdeveloped in CR animals. The dermal/vennule annulus vasculature is enlarged, and a vascular endothelial growth factor (VEGF switch and metabolic reprogramming in both the dermis and the epidermis are observed. When the fur coat is removed, CR mice display increased energy expenditure associated with lean weight loss and locomotion impairment. Our findings indicate that CR promotes extensive skin and fur remodeling. These changes are necessary for thermal homeostasis and metabolic fitness under conditions of limited energy intake, suggesting a potential adaptive mechanism.

  2. Caloric Restriction in Lean and Obese Strains of Laboratory ...

    Science.gov (United States)

    NEW FINDINGS: What is the central question of this study? How do lean and obese rats respond physiologically to caloric restriction? What is the main finding and its importance? Obese rats show marked benefits compared with lean animals. Reduced body fat is associated with improved longevity with caloric restriction (CR) in rodents. Little is known regarding effects of CR in genetically lean versus obese strains. Long-Evans (LE) and Brown Norway (BN) rats make an ideal comparison for a CR study because the percentage body fat of young adult LE rats is double that of BN rats. Male LE and BN rats were either fed ad libitum (AL) or were caloricallyrestricted to 80 or 90% of their AL weight. The percentages of fat, lean and fluid mass were measured non-invasively at 2- to 4-week intervals. Metabolic rate and respiratory quotient were measured after 3, 6, 9 and 12 months of CR. Overall health was scored monthly. The percentage of fat of the LE strain decreased with CR, whereas the percentage of fat of the BN strain remained above the AL group for several months. The percentage of lean mass increased above the AL for both strains subjected to CR. The percentage offluid was unaffected by CR. The average metabolic rate over 22 h of the BN rats subjected to CR was reduced, whereas that of LE rats was increased slightly above the AL group. The respiratory quotient of BN rats wasdecreased with CR. Overall health of the CR LE group was significantly improved compared with t

  3. Low Caloric Sweeteners for Diabetes and Obesity Care and Their

    Directory of Open Access Journals (Sweden)

    Mohammad Asif

    2015-10-01

    Full Text Available Diabetes and obesity are two common human disorders that affecting human health and invite various diseases and disorders in normal body functions. These diseases are very common worldwide. Diabetes occurs when high blood sugar levels develop. This happens when body can’t make and use all of the insulin it needs to blood sugar normally to keep blood sugar levels as normal as possible to control diabetes. Diabetic patients will need to follow a diet plan, do exercise and possibly take insulin injections. As part of eating plan, health care provider, and dietitian may ask to limit the amount of carbohydrates eat each day. Low-calorie sweeteners are one easy tool to help for follow eating plan. Obesity is more susceptible and often been associated with frequent ingestion of high energy food in high amount and high intake of sugars such as fermentable sugars such as sucrose, fructose, glucose, and maltose. Both diseases are may be genetically or due to hormonal imbalances. High energy sweeteners may causes caries in the teeth particularly susceptible to the children. Increased calorie intake associated with sugars and carbohydrates, especially when associated with physical inactivity, has been implicated in obesity. Fortunately, low calorie artificial and natural alternatives of sugars have been developed as alternatives to fermentable sugars and have shown promise in these health issues. Although there are only few artificial sweeteners (saccharin, aspartame, acesulfam potassium, sucralose, cyclamate that have been approved as food additives by the Food and Drug Administration and additional other low-caloric sweeteners (sugar alcohols, neotame, stevia, erythritol, xylitol, tagatose that have FDA-generally recognized as safe. Given the health impact of sugars and other carbohydrates, professionals should be aware of the marketed available low caloric sweeteners and both their benefits and potential risks.

  4. CFD Transient Simulation of an Isolator Shock Train in a Scramjet Engine

    Science.gov (United States)

    2012-09-01

    the imbalance in the equations used are tracked in terms of residuals to see if the residuals increase or decrease and to check and see if the... residuals reach an acceptable tolerance level when they decrease. For a transient simulation, the numerical convergence normally used in steady- state...averaging and Favre-averaging as described earlier in Section II) governing inviscid and viscous flows appropriate for calorically or thermally perfect

  5. Respostas pós-colheita de abacaxi 'Pérola' no tratamento com calor e armazenagem refrigerada

    Directory of Open Access Journals (Sweden)

    Rosilene Ferreira Souto

    2014-12-01

    Full Text Available Este trabalho teve como objetivo avaliar o efeito de diferentes temperaturas de armazenamento e do tratamento inicial a 40 ºC, por 24 horas, na preservação de abacaxis 'Pérola'. Os abacaxis foram colhidos no estádio de maturação "pintado", tratados com calor e foram mantidos sob condição de ambiente (25 ºC e 75-80% UR ou refrigerados durante 17 dias, a 8 ºC, ou 14 ºC. Após este período, foram transferidos para condição de ambiente, 25 ºC e 75-80% UR. As avaliações foram realizadas no início (0 dia e após 1; 5; 9; 13 ou 17 dias. Os frutos armazenados sob refrigeração foram transferidos para o ambiente e também foram avaliados aos 21, 25 ou 29 dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial (2x3x9, tendo-se os fatores, frutos tratados com calor ou não, três temperaturas de armazenamento e 9 épocas de avaliação. Os frutos foram avaliados quanto à perda de massa fresca, coloração externa, resistência da casca e da polpa, rendimento em polpa, além da intensidade respiratória. A perda de massa fresca e a resistência da casca e da polpa foram maiores nos frutos armazenados sob condição ambiente quando comparada à perda de massa e resistência dos abacaxis armazenados sob refrigeração, com variação na coloração da casca, de verde para amarela, com a evolução do tempo. Os abacaxis mantidos sob refrigeração a 8 ºC ou 14 ºC tiveram vida útil de 29 dias, enquanto os abacaxis mantidos a 25 ºC foram descartados após 17 dias. Abacaxis tratados com calor apresentaram a maior taxa respiratória, enquanto aqueles mantidos a 8 ºC apresentaram a menor atividade respiratória, tanto sob refrigeração como em condição ambiente.

  6. Transient drainage summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    This report summarizes the history of transient drainage issues on the Uranium Mill Tailings Remedial Action (UMTRA) Project. It defines and describes the UMTRA Project disposal cell transient drainage process and chronicles UMTRA Project treatment of the transient drainage phenomenon. Section 4.0 includes a conceptual cross section of each UMTRA Project disposal site and summarizes design and construction information, the ground water protection strategy, and the potential for transient drainage.

  7. Selective ion changes during spontaneous mitochondrial transients in intact astrocytes.

    Directory of Open Access Journals (Sweden)

    Guillaume Azarias

    Full Text Available The bioenergetic status of cells is tightly regulated by the activity of cytosolic enzymes and mitochondrial ATP production. To adapt their metabolism to cellular energy needs, mitochondria have been shown to exhibit changes in their ionic composition as the result of changes in cytosolic ion concentrations. Individual mitochondria also exhibit spontaneous changes in their electrical potential without altering those of neighboring mitochondria. We recently reported that individual mitochondria of intact astrocytes exhibit spontaneous transient increases in their Na(+ concentration. Here, we investigated whether the concentration of other ionic species were involved during mitochondrial transients. By combining fluorescence imaging methods, we performed a multiparameter study of spontaneous mitochondrial transients in intact resting astrocytes. We show that mitochondria exhibit coincident changes in their Na(+ concentration, electrical potential, matrix pH and mitochondrial reactive oxygen species production during a mitochondrial transient without involving detectable changes in their Ca(2+ concentration. Using widefield and total internal reflection fluorescence imaging, we found evidence for localized transient decreases in the free Mg(2+ concentration accompanying mitochondrial Na(+ spikes that could indicate an associated local and transient enrichment in the ATP concentration. Therefore, we propose a sequential model for mitochondrial transients involving a localized ATP microdomain that triggers a Na(+-mediated mitochondrial depolarization, transiently enhancing the activity of the mitochondrial respiratory chain. Our work provides a model describing ionic changes that could support a bidirectional cytosol-to-mitochondria ionic communication.

  8. Selective ion changes during spontaneous mitochondrial transients in intact astrocytes.

    Science.gov (United States)

    Azarias, Guillaume; Chatton, Jean-Yves

    2011-01-01

    The bioenergetic status of cells is tightly regulated by the activity of cytosolic enzymes and mitochondrial ATP production. To adapt their metabolism to cellular energy needs, mitochondria have been shown to exhibit changes in their ionic composition as the result of changes in cytosolic ion concentrations. Individual mitochondria also exhibit spontaneous changes in their electrical potential without altering those of neighboring mitochondria. We recently reported that individual mitochondria of intact astrocytes exhibit spontaneous transient increases in their Na(+) concentration. Here, we investigated whether the concentration of other ionic species were involved during mitochondrial transients. By combining fluorescence imaging methods, we performed a multiparameter study of spontaneous mitochondrial transients in intact resting astrocytes. We show that mitochondria exhibit coincident changes in their Na(+) concentration, electrical potential, matrix pH and mitochondrial reactive oxygen species production during a mitochondrial transient without involving detectable changes in their Ca(2+) concentration. Using widefield and total internal reflection fluorescence imaging, we found evidence for localized transient decreases in the free Mg(2+) concentration accompanying mitochondrial Na(+) spikes that could indicate an associated local and transient enrichment in the ATP concentration. Therefore, we propose a sequential model for mitochondrial transients involving a localized ATP microdomain that triggers a Na(+)-mediated mitochondrial depolarization, transiently enhancing the activity of the mitochondrial respiratory chain. Our work provides a model describing ionic changes that could support a bidirectional cytosol-to-mitochondria ionic communication.

  9. GLUTAMINA NA DIETA DE POEDEIRAS LEVES SUBMETIDAS AO ESTRESSE PELO CALOR E À TERMONEUTRALIDADE

    Directory of Open Access Journals (Sweden)

    KELEN CRISTIANE ZAVARIZE

    2011-09-01

    Full Text Available The aim of this study was to evaluate the effect of glutamine supplementation of the diet on intestinal mucosa morphology, performance, and egg quality of commercial laying hens, submitted to heat stress and thermoneutral conditions. In this study, 96 (Isa Babcock laying hens at 35 weeks of age were used and distributedin a completely randomized design according to a 2x2 factorial arrangement, with two levels of ambient temperature (thermoneutral and hot and two levels of glutamine in the diet (0.0 and 1.0% of inclusion, in 6 replicates of 4 hens per box. Feed intake, daily eggproduction, feed conversion per kilogram of eggs, and egg quality were obtained in two periods of 28 days each. Heat stress decreased egg production and quality, and glutamine supplementation improved egg quality and feed conversion. The heat and glutamine upplementationprovided an increase in calliciform cells quantity in duodenum and ileum, respectively. Significant morphological modifications in the intestinal mucosa of laying hens were not found.

  10. Influência do calor armazenado no sistema solo-planta no balanço de energia em pomar de mangueiras Influence of the heat stored in the soil-plant system in the energy balance over a mango orchard

    Directory of Open Access Journals (Sweden)

    Cícera J. R. Borges

    2008-08-01

    Full Text Available Neste estudo se objetivou a avaliação da contribuição do calor armazenado acima das placas de fluxo de calor no solo e no dossel vegetativo sobre os componentes do balanço de energia, no pomar de mangueiras. Os componentes do balanço de energia foram obtidos pelo método do balanço de energia com base na razão de Bowen. O teste t-Student foi usado para avaliar a existência de diferença significativa entre as médias dos componentes do balanço de energia, obtidas mediante as seguintes condições: (i considerando-se o calor armazenado acima dos fluxímetros e (ii desconsiderando-se o calor armazenado acima dos fluxímetros, cujos resultados indicaram que: 1 o efeito do calor armazenado no dossel vegetativo é irrelevante quando comparado com os outros componentes do balanço de energia em pomar de mangueiras; 2 o calor armazenado acima das placas de calor no solo não interfere significativamente no cálculo dos fluxos de calor sensível e latente nem na evapotranspiração da mangueira irrigada; 3 o fluxo de calor no solo, corrigido com o calor armazenado acima dos fluxímetros, difere estatisticamente a nível de 5% de probabilidade, daquele obtido sem a correção do fluxo.The objective of this study was to investigate the contribution of the heat storage above the soil heat flux plates and within the canopy upon the components of the energy balance in the mango orchard. The Bowen energy-ratio balance method was used for obtaining the energy balance components and evapotranspiration of the mango orchard. The t-Student test was applied to evaluate statistical significance of the difference between energy balance component averages under the following conditions: (i considering and (ii not considering the heat storage above the fluximeters. The results suggested that: 1 the canopy heat storage is irrelevant compared to the other energy balance components; 2 the above soil heat plates heat storage does not influence the sensible and

  11. Comparison of caloric intake and weight outcomes of an ad lib feeding regimen for preterm infants in two nurseries.

    Science.gov (United States)

    Pridham, K F; Kosorok, M R; Greer, F; Kayata, S; Bhattacharya, A; Grunwald, P

    2001-09-01

    Effects on caloric intake and weight gain of an ad libitum (ad lib) feeding regimen for preterm infants may be specific to a special care nursery. To explore across two nurseries the similarity of effect on caloric intake and weight gain of an ad lib feeding regimen compared with a prescribed regimen and the similarity of effect of caloric intake on weight gain. All infants participating in the multi-site randomized clinical trial (RCT) of the ad lib feeding regimen were lib. After accounting for caloric intake, the ad lib regimen did not affect weight gain. The time-by-regimen interaction effect on caloric intake was significant in both nurseries. Caloric intake for infants fed ad lib increased significantly over 5 days. Despite differences between nurseries in infant characteristics and in protocol implementation, the feeding regimen effect was consistent for caloric intake and weight gain. Further support was found for the development of infant self-regulatory capacity.

  12. Do nistagmo às provas calóricas com ar e com água From nystagmus to the air and water caloric tests

    Directory of Open Access Journals (Sweden)

    Anna Carolina Marques Perrella de Barros

    2012-08-01

    Full Text Available A prova calórica é uma importante ferramenta na avaliação da função labiríntica. OBJETIVO: Comparar o nistagmo pós-calórico da prova com ar a 50ºC e 24ºC com o da prova com água a 44ºC e 30ºC. Desenho científico: Estudo clínico cruzado randomizado. MATERIAL E MÉTODO: 40 indivíduos hígidos submetidos à avaliação da função vestibular incluindo a prova calórica com ar a 50ºC e 24ºC e com água a 44ºC e 30ºC. RESULTADOS: À comparação das provas com ar e com água, não houve diferença significante entre os valores da velocidade angular da componente lenta (VACL do nistagmo pós-calórico quanto à ordem de realização das estimulações, entre as orelhas e entre os valores de predomínio labiríntico e de preponderância direcional. Os valores da VACL foram maiores nas estimulações com água (p = 0,008; p The caloric test is an important tool for the assessment of labyrinthine function. OBJECTIVE: To compare the nystagmus response in the caloric tests with air at 50ºC and 24ºC and with water at 44ºC and 30ºC. Study Design: Randomized crossover clinical trial. MATERIALS AND METHODS: 40 healthy individuals were submitted to a neurotological evaluation, including caloric tests with air at 50ºC and 24ºC and water at 44ºC and 30ºC. RESULTS: Comparing the air and water caloric tests, there were no significant differences among the post-caloric nystagmus slow-phase velocity in relation to the stimulation order, between ears and between the values of unilateral weakness and directional preponderance. The slow-phase velocity values were higher with water (p = 0.008, p < 0.001, and cold stimulation produced stronger responses (p < 0.001. CONCLUSION: Comparing 50ºC and 24ºC air caloric test and 44ºC and 30ºC water caloric test, we observed similar slow-phase velocity values for both ears, higher responses in the cold temperature and in the test with water, and similar results of unilateral weakness or directional

  13. Is contextual-potentiated eating dependent on caloric density of food?

    Directory of Open Access Journals (Sweden)

    Fernando Fernández-Aranda

    2009-01-01

    Full Text Available One experiment tested whether a specific context could elicit eating in rats as a result of Pavlovian conditioning and whether this effect depended on the caloric density of food. Thirty two deprived rats experienced two contexts. They had access to food in context A, but no food was available in context B. During conditioning, half of the animals received high density caloric food (HD groups whereas the other half, low density caloric food (LD groups. Then, half of the rats in each type of food group was tested in context A and the other half in context B. The results demonstrated an effect of context conditioning only in HD groups. These findings suggest the relevance of both contextual conditioning and caloric density of food in eating behaviour. Implications for the aetiology of binge eating will be discussed.

  14. Automobilismo: no calor da competição Automovilismo: en el calor de la competición Car racing: in the heat of competition

    OpenAIRE

    Luiz Oswaldo Carneiro Rodrigues; Flávio de Castro Magalhães

    2004-01-01

    O presente artigo questiona o papel do calor como um fator de risco adicional para o acidente que vitimou Ayrton Senna. O automobilismo de competição constitui um desafio biológico, uma situação estressante do ponto de vista mental e físico. A manutenção da performance depende da disponibilidade de carboidratos e oxigênio, hidratação adequada e temperatura interna constante entre 37 e 38 graus centígrados. A dissipação do calor produzido pelo metabolismo ocorre através do aumento do fluxo de ...

  15. Fasting and Caloric Restriction in Cancer Prevention and Treatment.

    Science.gov (United States)

    Brandhorst, Sebastian; Longo, Valter D

    Cancer is the second leading cause of death in the USA and among the leading major diseases in the world. It is anticipated to continue to increase because of the growth of the aging population and prevalence of risk factors such as obesity, smoking, and/or poor dietary habits. Cancer treatment has remained relatively similar during the past 30 years with chemotherapy and/or radiotherapy in combination with surgery remaining the standard therapies although novel therapies are slowly replacing or complementing the standard ones. According to the American Cancer Society, the dietary recommendation for cancer patients receiving chemotherapy is to increase calorie and protein intake. In addition, there are no clear guidelines on the type of nutrition that could have a major impact on cancer incidence. Yet, various forms of reduced caloric intake such as calorie restriction (CR) or fasting demonstrate a wide range of beneficial effects able to help prevent malignancies and increase the efficacy of cancer therapies. Whereas chronic CR provides both beneficial and detrimental effects as well as major compliance challenges, periodic fasting (PF), fasting-mimicking diets (FMDs), and dietary restriction (DR) without a reduction in calories are emerging as interventions with the potential to be widely used to prevent and treat cancer. Here, we review preclinical and preliminary clinical studies on dietary restriction and fasting and their role in inducing cellular protection and chemotherapy resistance.

  16. Palatable Hyper-Caloric Foods Impact on Neuronal Plasticity.

    Science.gov (United States)

    Morin, Jean-Pascal; Rodríguez-Durán, Luis F; Guzmán-Ramos, Kioko; Perez-Cruz, Claudia; Ferreira, Guillaume; Diaz-Cintra, Sofia; Pacheco-López, Gustavo

    2017-01-01

    Neural plasticity is an intrinsic and essential characteristic of the nervous system that allows animals "self-tuning" to adapt to their environment over their lifetime. Activity-dependent synaptic plasticity in the central nervous system is a form of neural plasticity that underlies learning and memory formation, as well as long-lasting, environmentally-induced maladaptive behaviors, such as drug addiction and overeating of palatable hyper-caloric (PHc) food. In western societies, the abundance of PHc foods has caused a dramatic increase in the incidence of overweight/obesity and related disorders. To this regard, it has been suggested that increased adiposity may be caused at least in part by behavioral changes in the affected individuals that are induced by the chronic consumption of PHc foods; some authors have even drawn attention to the similarity that exists between over-indulgent eating and drug addiction. Long-term misuse of certain dietary components has also been linked to chronic neuroimmune maladaptation that may predispose individuals to neurodegenerative conditions such as Alzheimer's disease. In this review article, we discuss recent evidence that shows how consumption of PHc food can cause maladaptive neural plasticity that converts short-term ingestive drives into compulsive behaviors. We also discuss the neural mechanisms of how chronic consumption of PHc foods may alter brain function and lead to cognitive impairments, focusing on prenatal, childhood and adolescence as vulnerable neurodevelopmental stages to dietary environmental insults. Finally, we outline a societal agenda for harnessing permissive obesogenic environments.

  17. Use of caloric and noncaloric sweeteners in US consumer packaged foods, 2005-2009.

    Science.gov (United States)

    Ng, Shu Wen; Slining, Meghan M; Popkin, Barry M

    2012-11-01

    Our understanding of the use of caloric and noncaloric sweeteners in the US food supply is limited. This study uses full ingredient list and Nutrition Facts label data from Gladson Nutrition Database and nationally representative purchases of consumer packaged foods from Nielsen Homescan in 2005 through 2009 to understand the use of caloric sweeteners (including fruit juice concentrate) and noncaloric sweeteners in consumer packaged foods. Of the 85,451 uniquely formulated foods purchased during 2005 through 2009, 75% contain sweeteners (68% with caloric sweetener only, 1% with noncaloric sweetener only, 6% with both caloric and noncaloric sweeteners). Caloric sweetener are in >95% of cakes/cookies/pies, granola/protein/energy bars, ready-to-eat cereals, sweet snacks, and sugar-sweetened beverages. Noncaloric sweetener are in >33% of yogurts and sport/energy drinks, 42% of waters (plain or flavored), and most dietetic sweetened beverages. Across unique products, corn syrup is the most commonly listed sweetener, followed by sorghum, cane sugar, high-fructose corn syrup, and fruit juice concentrate. Also, 77% of all calories purchased in the United States in 2005-2009 contained caloric sweeteners and 3% contained noncaloric sweeteners, and 73% of the volume of foods purchased contained caloric sweetener and 15% contained noncaloric sweetener. Trends during this period suggest a shift toward the purchase of noncaloric sweetener-containing products. Our study poses a challenge toward monitoring sweetener consumption in the United States by discussing the need and options available to improve measures of caloric sweetener and noncaloric sweetener and additional requirements on Nutrition Facts labels on consumer packaged foods.

  18. Caloric restriction decreases orthostatic tolerance independently from 6° head-down bedrest.

    Directory of Open Access Journals (Sweden)

    John P Florian

    Full Text Available Astronauts consume fewer calories during spaceflight and return to earth with an increased risk of orthostatic intolerance. Whether a caloric deficiency modifies orthostatic responses is not understood. Thus, we determined the effects of a hypocaloric diet (25% caloric restriction during 6° head down bedrest (an analog of spaceflight on autonomic neural control during lower body negative pressure (LBNP. Nine healthy young men completed a randomized crossover bedrest study, consisting of four (2 weeks each interventions (normocaloric bedrest, normocaloric ambulatory, hypocaloric bedrest, hypocaloric ambulatory, each separated by 5 months. Muscle sympathetic nerve activity (MSNA was recorded at baseline following normocaloric and hypocaloric interventions. Heart rate (HR and arterial pressure were recorded before, during, and after 3 consecutive stages (7 min each of LBNP (-15, -30, -45 mmHg. Caloric and posture effects during LBNP were compared using two-way ANOVA with repeated measures. There was a strong trend toward reduced basal MSNA following caloric restriction alone (normcaloric vs. hypocaloric: 22±3 vs. 14±4 burst/min, p = 0.06. Compared to the normocaloric ambulatory, both bedrest and caloric restriction were associated with lower systolic blood pressure during LBNP (p<0.01; however, HR responses were directionally opposite (i.e., increase with bedrest, decrease with caloric restriction. Survival analysis revealed a significant reduction in orthostatic tolerance following caloric restriction (normocaloric finishers: 12/16; hypocaloric finishers: 6/16; χ2, p = 0.03. Caloric restriction modifies autonomic responses to LBNP, which may decrease orthostatic tolerance after spaceflight.

  19. Comparison of standardized versus individualized caloric prescriptions in the nutritional rehabilitation of inpatients with anorexia nervosa

    Science.gov (United States)

    Haynos, Ann F.; Snipes, Cassandra; Guarda, Angela; Mayer, Laurel E.; Attia, Evelyn

    2015-01-01

    Objective Sparse research informs how caloric prescriptions should be advanced during nutritional rehabilitation of inpatients with anorexia nervosa (AN). This study compared the impact of a standardized caloric increase approach, in which increases occurred on a predetermined schedule, to an individualized approach, in which increases occurred only following insufficient weight gain, on rate, pattern, and cumulative amount of weight gain and other weight restoration outcomes. Method This study followed a natural experiment design comparing AN inpatients consecutively admitted before (n = 35) and after (n = 35) an institutional change from individualized to standardized caloric prescriptions. Authors examined the impact of prescription plan on weekly weight gain in the first treatment month using multilevel modeling. Within a subsample remaining inpatient through weight restoration (n = 40), multiple regressions examined the impact of caloric prescription plan on time to weight restoration, length of hospitalization, maximum caloric prescription, discharge BMI, and incidence of activity restriction and edema. Results There were significant interactions between prescription plan and quadratic time on average weekly weight gain (p = .03) and linear time on cumulative weekly weight gain (p < .001). Under the standardized plan, patients gained in an accelerated curvilinear pattern (p = .04) and, therefore, gained cumulatively greater amounts of weight over time (p < .001). Additionally, 30% fewer patients required activity restriction under the standardized plan. Discussion Standardized caloric prescriptions may confer advantage by facilitating accelerated early weight gain and lower incidence of bed rest without increasing the incidence of refeeding syndrome. PMID:26769581

  20. Herdabilidade da necessidade de calor para a antese e brotação em pessegueiro

    Directory of Open Access Journals (Sweden)

    Citadin Idemir

    2003-01-01

    Full Text Available A herdabilidade da necessidade de calor para antese e brotação em pessegueiro [Prunus persica (L. Batsch] foi estudada em ramos de 16 cultivares e seleções de baixa, média e alta necessidade de calor e 11 progênies oriundas de hibridações entre elas. Os ramos foram submetidos, previamente, a 2 ºC por 500 horas para satisfazer a necessidade de frio. O valor estimado da herdabilidade média para a necessidade de calor em gemas florais foi de 45% e 57%, em 1999 e 2000, respectivamente. Para gemas vegetativas, o valor estimado foi de 30%, em 1999. 'BR-1', 'Barbosa', 'Chula', 'Chinoca' e 'Eldorado' transmitem melhor o caráter necessidade de calor para as progênies do que os demais genótipos estudados. Os registros observados suportam um modelo de herança quantitativa com genes de maior efeito para menor necessidade de calor. A seleção de indivíduos com maior necessidade de calor para floração tende a retardar a floração sem, contudo, retardar com a mesma intensidade a época de brotação.

  1. Caloric stimulation with near infrared radiation does not induce paradoxical nystagmus.

    Science.gov (United States)

    Walther, L E; Asenov, D R; Di Martino, E

    2011-04-01

    Near infrared radiation can be used for warm stimulation in caloric irrigation of the equilibrium organ. Aim of this study was to determine whether near infrared radiation offers effective stimulation of the vestibular organ, whether it is well tolerated by the patients and especially whether it is a viable alternative to warm air stimulation in patients with defects of the tympanic membrane and radical mastoid cavities. Patients with perforations of the tympanic membrane (n = 15) and with radical mastoid cavities (n = 13) were tested both with near infrared radiation and warm dry air. A caloric-induced nystagmus could be seen equally effectively and rapidly in all patients. Contrary to stimulation with warm dry air, no paradoxical nystagmus was observed following caloric irrigation with a warm stimulus (near infrared radiation). Results of a questionnaire showed excellent patient acceptance of near infrared stimulation with no arousal effects or unpleasant feeling. In conclusion, near infrared radiation proved to be an alternative method of caloric irrigation to warm dry air in patients with tympanic membrane defects and radical mastoid cavities. Near infrared radiation is pleasant, quick, contact free, sterile and quiet. With this method an effective caloric warm stimulus is available. If near infrared radiation is used for caloric stimulus no evaporative heat loss occurs.

  2. The effect of physical exercise and caloric restriction on the components of metabolic syndrome

    Directory of Open Access Journals (Sweden)

    Francisco Leonardo Torres-Leal

    2009-09-01

    Full Text Available Recent studies of the effects of physical exercise and caloric restriction have found several benefits on the metabolic and cardiovascular risk factors related to metabolic syndrome (MS. This review examines the current state of knowledge of the effects of physical exercise on the main pathologies associated with MS: obesity, insulin resistance, type 2 diabetes mellitus (DM2, dyslipidemias and hypertension. Although there are only a few randomized and controlled studies that evaluated the prevention and treatment of MS, strong evidence from controlled studies indicates that lifestyle changes that include regular physical exercise and caloric restriction are effective in preventing and treating DM2 in overweight individuals with reduced glucose tolerance. Likewise, epidemiologic studies suggest that regular physical exercise prevents the development of DM2 and cardiovascular disease. Based on current recommendations, it is important to increase the level of physical exercise at a moderate intensity to achieve good cardiorespiratory and muscular conditions and to promote fat mass reduction, with consequent reductions of risk of developing metabolic syndrome.Recentes estudos, relativos aos efeitos do exercício físico e da restrição energética, têm relatado diversos benefícios sobre fatores metabólicos e de risco cardiovascular relacionados à síndrome metabólica (SM. Esta revisão aborda os aspectos mais recentes dos efeitos do exercício físico sobre as principais patologias associadas à SM: obesidade, resistência à insulina, diabetes mellitus tipo 2 (DM2, dislipidemia e hipertensão. Embora estudos randomizados e controlados que avaliam a prevenção e o tratamento da SM sejam escassos, pesquisas controladas indicam fortes evidências de que mudanças no estilo de vida, incluindo a pratica de exercício físico regular e restrição energética, sejam eficazes na prevenção e tratamento de DM2 em indivíduos com sobrepeso e com

  3. Transient Voltage Recorder

    Science.gov (United States)

    Medelius, Pedro J. (Inventor); Simpson, Howard J. (Inventor)

    2002-01-01

    A voltage transient recorder can detect lightning induced transient voltages. The recorder detects a lightning induced transient voltage and adjusts input amplifiers to accurately record transient voltage magnitudes. The recorder stores voltage data from numerous monitored channels, or devices. The data is time stamped and can be output in real time, or stored for later retrieval. The transient recorder, in one embodiment, includes an analog-to-digital converter and a voltage threshold detector. When an input voltage exceeds a pre-determined voltage threshold, the recorder stores the incoming voltage magnitude and time of arrival. The recorder also determines if its input amplifier circuits clip the incoming signal or if the incoming signal is too low. If the input data is clipped or too low, the recorder adjusts the gain of the amplifier circuits to accurately acquire subsequent components of the lightning induced transients.

  4. TRANSIENT ELECTRONICS CATEGORIZATION

    Science.gov (United States)

    2017-08-24

    definitions of what it means to be transient. The purpose of this technical report is to provide a background of the issues related to transient...In this section, we will attempt to identify these parameters and provide preliminary definitions for categories of transience behavior. Transient...programmable lifetimes. Ideally , such materials with expiration dates will deconstruct themselves into harmless and invisible remnants. The technology base

  5. The Zwicky Transient Facility

    CERN Document Server

    Bellm, Eric C

    2014-01-01

    The Zwicky Transient Facility (ZTF) is a next-generation optical synoptic survey that builds on the experience and infrastructure of the Palomar Transient Factory (PTF). Using a new 47 deg$^2$ survey camera, ZTF will survey more than an order of magnitude faster than PTF to discover rare transients and variables. I describe the survey and the camera design. Searches for young supernovae, fast transients, counterparts to gravitational-wave detections, and rare variables will benefit from ZTF's high cadence, wide area survey.

  6. Palatable Hyper-Caloric Foods Impact on Neuronal Plasticity

    Science.gov (United States)

    Morin, Jean-Pascal; Rodríguez-Durán, Luis F.; Guzmán-Ramos, Kioko; Perez-Cruz, Claudia; Ferreira, Guillaume; Diaz-Cintra, Sofia; Pacheco-López, Gustavo

    2017-01-01

    Neural plasticity is an intrinsic and essential characteristic of the nervous system that allows animals “self-tuning” to adapt to their environment over their lifetime. Activity-dependent synaptic plasticity in the central nervous system is a form of neural plasticity that underlies learning and memory formation, as well as long-lasting, environmentally-induced maladaptive behaviors, such as drug addiction and overeating of palatable hyper-caloric (PHc) food. In western societies, the abundance of PHc foods has caused a dramatic increase in the incidence of overweight/obesity and related disorders. To this regard, it has been suggested that increased adiposity may be caused at least in part by behavioral changes in the affected individuals that are induced by the chronic consumption of PHc foods; some authors have even drawn attention to the similarity that exists between over-indulgent eating and drug addiction. Long-term misuse of certain dietary components has also been linked to chronic neuroimmune maladaptation that may predispose individuals to neurodegenerative conditions such as Alzheimer’s disease. In this review article, we discuss recent evidence that shows how consumption of PHc food can cause maladaptive neural plasticity that converts short-term ingestive drives into compulsive behaviors. We also discuss the neural mechanisms of how chronic consumption of PHc foods may alter brain function and lead to cognitive impairments, focusing on prenatal, childhood and adolescence as vulnerable neurodevelopmental stages to dietary environmental insults. Finally, we outline a societal agenda for harnessing permissive obesogenic environments. PMID:28261067

  7. Cardioprotective Signature of Short-Term Caloric Restriction.

    Directory of Open Access Journals (Sweden)

    Hossein Noyan

    Full Text Available To understand the molecular pathways underlying the cardiac preconditioning effect of short-term caloric restriction (CR.Lifelong CR has been suggested to reduce the incidence of cardiovascular disease through a variety of mechanisms. However, prolonged adherence to a CR life-style is difficult. Here we reveal the pathways that are modulated by short-term CR, which are associated with protection of the mouse heart from ischemia.Male 10-12 wk old C57bl/6 mice were randomly assigned to an ad libitum (AL diet with free access to regular chow, or CR, receiving 30% less food for 7 days (d, prior to myocardial infarction (MI via permanent coronary ligation. At d8, the left ventricles (LV of AL and CR mice were collected for Western blot, mRNA and microRNA (miR analyses to identify cardioprotective gene expression signatures. In separate groups, infarct size, cardiac hemodynamics and protein abundance of caspase 3 was measured at d2 post-MI.This short-term model of CR was associated with cardio-protection, as evidenced by decreased infarct size (18.5±2.4% vs. 26.6±1.7%, N=10/group; P=0.01. mRNA and miR profiles pre-MI (N=5/group identified genes modulated by short-term CR to be associated with circadian clock, oxidative stress, immune function, apoptosis, metabolism, angiogenesis, cytoskeleton and extracellular matrix (ECM. Western blots pre-MI revealed CR-associated increases in phosphorylated Akt and GSK3ß, reduced levels of phosphorylated AMPK and mitochondrial related proteins PGC-1α, cytochrome C and cyclooxygenase (COX IV, with no differences in the levels of phosphorylated eNOS or MAPK (ERK1/2; p38. CR regimen was also associated with reduced protein abundance of cleaved caspase 3 in the infarcted heart and improved cardiac function.

  8. Poor Prognosis After Second Locoregional Recurrences in the CALOR Trial.

    Science.gov (United States)

    Wapnir, Irene L; Gelber, Shari; Anderson, Stewart J; Mamounas, Eleftherios P; Robidoux, André; Martín, Miguel; Nortier, Johan W R; Geyer, Charles E; Paterson, Alexander H G; Láng, István; Price, Karen N; Coates, Alan S; Gelber, Richard D; Rastogi, Priya; Regan, Meredith M; Wolmark, Norman; Aebi, Stefan

    2017-02-01

    Isolated locoregional recurrences (ILRRs) of breast cancer confer a significant risk for the development of distant metastasis. Management practices and second ILRR events in the Chemotherapy as Adjuvant for LOcally Recurrent breast cancer (CALOR) trial were investigated. In this study, 162 patients with ILRR were randomly assigned to receive postoperative chemotherapy or no chemotherapy. Descriptive statistics characterize outcomes according to local therapy and the influence of hormone receptor status on subsequent recurrences. Competing risk regression models, Kaplan-Meier estimates, and Cox proportional hazards models were used to evaluate associations between treatment, site of second recurrence, and outcome. The median follow-up period was 4.9 years. Of the 98 patients who received breast-conserving primary surgery 89 had an ipsilateral-breast tumor recurrence. Salvage mastectomy was performed for 73 patients and repeat lumpectomy for 16 patients. Another eight patients had nodal ILRR, and one patient had chest wall ILRR. Among 64 patients whose primary surgery was mastectomy, 52 had chest wall/skin ILRR, and 12 had nodal ILRR. For 15 patients, a second ILRR developed a median of 1.6 years (range 0.08-4.8 years) after ILRR. All second ILRRs occurred for patients with progesterone receptor-negative ILRR. Death occurred for 7 (47 %) of 15 patients with a second ILRR and 19 (51 %) of 37 patients with a distant recurrence. As shown in the multivariable analysis, the significant predictors of survival after either a second ILRR or distant recurrence were chemotherapy for the primary cancer (hazard ratio [HR], 3.55; 95 % confidence interval [CI], 1.15-10.9; p = 0.03) and the interval (continuous) from the primary surgery (HR, 0.87; 95 % CI, 0.75-1.00; p = 0.05). Second ILRRs represented about one third of all recurrence events after ILRR, and all were PR-negative. These second ILRRs and distant metastases portend an unfavorable outcome.

  9. Solución numérica de procesos de transferencia de calor en aleaciones con condiciones de contorno no lineales

    Directory of Open Access Journals (Sweden)

    Alhama, F.

    2005-12-01

    Full Text Available Thermal properties of a great number of alloys, especially specific heat, show a sharply temperature dependence both during the phase change and the allotropic transformations. This fact, in conjunction with the existence of convection or radiation boundary conditions, or both simultaneously, increase the complexity of the transient heat transfer problem because of the inherent no linearity. The numerical model proposed for the solution of this problem is able to assume the above hypothesis as well as the temperature dependencies of the thermal conductivity. Applications to alloys are presented.

    Las propiedades térmicas de numerosas aleaciones, especialmente la capacidad calorífica, acusan una marcada dependencia con la temperatura tanto en los cambios de fase como en las transformaciones alotrópicas. Este hecho, junto con la aplicación de condiciones de contorno de convección, radiación o ambas, simultáneamente, aumentan la complejidad del problema de transferencia de calor en los procesos transitorios debido a la no linealidad inherente. El modelo numérico propuesto para la solución de este problema es capaz de asumir las hipótesis anteriores así como las posibles dependencias de la conductividad térmica con la temperatura. Se presentan aplicaciones a procesos térmicos en aleaciones.

  10. Determinaciones termogravimétricas y de calor específico de un concentrado comercial de ulexita, entre temperatura ambiente y 1.000 ºC

    Directory of Open Access Journals (Sweden)

    Flores, H. R.

    2006-12-01

    Full Text Available The important amount of hydration water in the ulexite (NaCaB5O9.8H2O, allows using calcination methods to increase its B2O3 content. This paper analyses the thermal decomposition reaction of a preconcentrated ulexite through weight loss measurements, which occur during the heating of samples until 1000 ºC. Determinations of heat content at each temperature were made using an isoperibol calorimeter. The mean specific heat was calculated from these values, and its dependence on temperature was determined. The maximum weight loss was about 32.5 % and the specific heat obtained was 1,13 kJ/kgºC for solid samples and 1,38 kJ/kgºC for fluid samples.The results are useful for the design of the industrial process, in order to determine the thermal requirements for heating calcined ulexite, and to obtain smelted ulexite.

    El elevado contenido de agua de hidratación de la ulexita (NaCaB5O9.8H2O permite utilizar la calcinación como método de concentración. En este trabajo se analiza la reacción de descomposición térmica de un preconcentrado de ulexita a través de determinaciones de la pérdida de peso ocurrida durante el calentamiento de la muestra hasta 1000 ºC. Por otra parte, se ha determinado el valor del calor sensible a cada temperatura ensayada mediante un calorímetro tipo isoperibol y se ha calculado el calor específico medio de la muestra calcinada, así como su variación con la temperatura. Se obtuvieron pérdidas de peso de 32,5 % y valores del calor específico de 1,13 kJ/kgºC para muestras sólidas y 1,38 kJ/kgºC para las fluidas. Los resultados son de utilidad para el diseño del proceso industrial, para la determinación del requerimiento térmico para el calentamiento de ulexita calcinada y para la obtención de una frita.

  11. Heat and mass transfer during the warming of a bottle of beer = Transferência de calor e massa durante o aquecimento de uma garrafa de cerveja

    Directory of Open Access Journals (Sweden)

    Cláudio Vinicius Barbosa Monteiro

    2010-07-01

    Full Text Available The warming of a bottle of beer during a Friday evening happy hour directly involves transport phenomena, such as mass transfer due to condensation of air humidity on the bottle surface and heat transfer from the ambient to the bottle, which occurs by free convection and water condensation. Both processes happen simultaneously and are directly associated with the heat and mass transfer coefficients involved, which are affected by the ambient humidity and temperature. Several runs were made in several ambient conditions by exposing a cold bottle of beer to varied temperature and humidity and measuring the temperature of beer and the mass of water condensed on the bottle surface over time. From these measures, a theoretical and experimental methodology was developed and applied for the evaluation of the heat and mass transfer coefficients that govern this process. Both the relative humidity and ambient temperature exert a significant influence on the convective heat transfer coefficient. However, the mass transfer coefficient is affected only by the temperature.O aquecimento de uma garrafa de cerveja num “happy-hour” de sexta a tarde envolve diretamente os fenômenos de transferência de massa, devido à condensação da umidade do ar na superfície da garrafa, e de transferência de calor do meio para a garrafa, que ocorre por convecção natural e por condensação de vapor de água. Ambos os processos ocorrem simultaneamente e estão diretamente associados aos coeficientes de transferência de calor e massa envolvidos na dinâmica destes fenômenos e sofrem influência direta da umidade e temperatura ambientes. Neste contexto, efetuaram-se ensaios em diversas condições de temperatura e umidade ambientes, expondo-se uma garrafa de cerveja gelada ao ambiente e medindo-se a temperatura da cerveja e a massa de água condensada ao longo do tempo. A partir destas medidas, desenvolveu-se uma metodologia teórico-experimental que proporcionou a

  12. Effects of caloric vestibular stimulation on serotoninergic system in the media vestibular nuclei of guinea pigs

    Institute of Scientific and Technical Information of China (English)

    MA Fu-rong; LIU Jun-xiu; LI Xue-pei; MAO Jian-jun; ZHANG Qun-dan; JIA Hong-bo; MAO Lan-quan; ZHAO Rui

    2007-01-01

    Background Anatomic and electrophysiological studies have revealed that the neurons located in the media vestibular nuclei (MVN) receive most of the sensory vestibular input coming from the ipsilateral labyrinth and the responses of MVN neurons to caloric stimulation directly reflect changes in primary vestibular afferent activity. The aim of this study was to clarify the intrinsic characteristics of serotonin (5-hydroxytryptamine, 5-HT) release in the MVN during the period of vertigo induced by caloric stimulation.Methods We used an in vivo microdialysis technique to examine the effects of caloric stimulation on the serotoninergic system in MVN. Twenty four guinea pigs were randomly divided into the groups of irrigation of the ear canal with hot water (n=6), ice water (n=6) and 37℃ water (n=4), and the groups of irrigation of the auricle with hot water (n=4) and ice water (n=4), according to different caloric vestibular stimulation. We examined the animal's caloric nystagmus with a two-channel electronystagmographic recorder (ENG), and meanwhile examine serotonin (5-hydroxytryptamine, 5-HT) level in the MVN with microdialysis technique after caloric stimulation. Results In the caloric test the hot water (44℃) irrigation of the right external auditory canal induced horizontal nystagmus towards the right side lasting about 60 seconds and the ice water irrigation of the right external auditory canal induced it towards the left side lasting for about 90 seconds. No nystagmus was induced by 37℃ water irrigation of the external ear canal. Therefore, it was used as a negative control stimulation to the middle ear. The MVN 5-HT levels significantly increased in the first 5-minute collecting interval and increased to 254% and 189% of the control group in the second collecting interval in response to caloric vestibular stimulation with ice water and hot water respectively. The serotonin release was not distinctly changed by the irrigation of the auricle with ice water

  13. The Lexicocalorimeter: Gauging public health through caloric input and output on social media

    Science.gov (United States)

    Alajajian, Sharon E.; Williams, Jake Ryland; Reagan, Andrew J.; Alajajian, Stephen C.; Frank, Morgan R.; Mitchell, Lewis; Lahne, Jacob; Danforth, Christopher M.; Dodds, Peter Sheridan

    2017-01-01

    We propose and develop a Lexicocalorimeter: an online, interactive instrument for measuring the “caloric content” of social media and other large-scale texts. We do so by constructing extensive yet improvable tables of food and activity related phrases, and respectively assigning them with sourced estimates of caloric intake and expenditure. We show that for Twitter, our naive measures of “caloric input”, “caloric output”, and the ratio of these measures are all strong correlates with health and well-being measures for the contiguous United States. Our caloric balance measure in many cases outperforms both its constituent quantities; is tunable to specific health and well-being measures such as diabetes rates; has the capability of providing a real-time signal reflecting a population’s health; and has the potential to be used alongside traditional survey data in the development of public policy and collective self-awareness. Because our Lexicocalorimeter is a linear superposition of principled phrase scores, we also show we can move beyond correlations to explore what people talk about in collective detail, and assist in the understanding and explanation of how population-scale conditions vary, a capacity unavailable to black-box type methods. PMID:28187216

  14. A Biomechanical Model of the Inner Ear: Numerical Simulation of the Caloric Test

    Directory of Open Access Journals (Sweden)

    Shuang Shen

    2013-01-01

    Full Text Available Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  15. A biomechanical model of the inner ear: numerical simulation of the caloric test.

    Science.gov (United States)

    Shen, Shuang; Liu, Yingxi; Sun, Xiuzhen; Zhao, Wei; Su, Yingfeng; Yu, Shen; Liu, Wenlong

    2013-01-01

    Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC) cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  16. Efecto del calor aportado en recargues nanoestructurados base hierro

    Directory of Open Access Journals (Sweden)

    Agustín Gualco

    2013-12-01

    Full Text Available En los últimos años se han desarrollado consumibles de soldadura que depositan recubrimientos duros de aleaciones base hierro nanoestructuradas de gran resistencia al desgaste abrasivo. Las resistencias al desgaste erosivo y abrasivo están controladas principalmente por la composición química y la microestructura. A su vez, la microestructura del metal depositado puede presentar variaciones con el procedimiento de soldadura empleado, especialmente en relación al aporte térmico. Los parámetros operativos que definen el aporte térmico (tensión, corriente y velocidad de soldadura afectan aspectos como la geometría del cordón (ancho, penetración y sobremonta y la dilución con el material base. El propósito de este trabajo fue estudiar el efecto del calor aportado sobre las características geométricas del cordón, la dilución y la evolución microestructural de una aleación nanoestructurada base hierro, depositada por FCAW. Se soldaron muestras con aportes térmicos de entre 0,5 y 3,5 kJ/mm. Sobre cada cupón soldado se realizó un relevamiento dimensional, se analizó la composición química y se caracterizó la microestructura usando microscopías óptica y electrónica de barrido y difracción de rayos X. También se midieron la microdureza del depósito, el tamaño de cristalita y el grado de dilución. Se observó una gran influencia de las condiciones de proceso sobre la geometría del cordón. La dilución varió entre un 30 y un 40%, la microdureza del depósito se encontró entre 800 y 870 HV1 y el tamaño de cristalita osciló entre 105 y 130 nm, en función de las variables de proceso empleadas. Las mayores durezas y los menores tamaños de cristalita se obtuvieron con el menor aporte térmico, asociado a una menor dilución.

  17. IDENTIFICAÇÃO DE ILHAS DE CALOR POR MEIO DE SENSORIAMENTO REMOTO: ESTUDO DE CASO NO MUNICÍPIO DE GOIÂNIA – GO/2001

    Directory of Open Access Journals (Sweden)

    Diego Tarley Ferreira Nascimento

    2009-06-01

    Full Text Available No presente trabalho são utilizadas técnicas de sensoriamento remoto para identificação e análise do fenômeno de ilhas de calor em Goiânia-GO, tendo como recorte temporal o ano de 2001. Foi utilizada a proposta metodológica de Monteiro (1976, do Sistema de Clima Urbano – SCU, em particular o subsistema Termodinâmico, visando proceder a uma análise do funcionamento, desempenho e organização do fenômeno de ilhas de calor. A elaboração do trabalho baseou-se na classificação da cobertura do solo e em um mapeamento do campo térmico do município de Goiânia, por meio das imagens das bandas 3, 4, 5 e 6 (banda termal do Landsat 7, nas quais foram considerados como instrumentos de análise: a urbanização, as características geoecológicas (topografia e o sistema meteorológico (clima regional. Os resultados demonstram que o fenômeno de ilha de calor é constatado no município de Goiânia, havendo diferenças de temperatura de até 10°C entre a área urbana e a rural do município, sendo possível caracterizar determinados usos antrópicos (classes de cobertura do solo e intervalos altimétricos como potencializadores de maiores valores de temperatura.

  18. O estudo da prova calórica em pacientes idoso The study of caloric testing in senior patients

    Directory of Open Access Journals (Sweden)

    Débora Cristina de Oliveira Bezerra

    2008-01-01

    Full Text Available OBJETIVO: realizar o estudo da prova calórica em pacientes idosos com queixa de tontura, acompanhada ou não de zumbido com finalidade de traçar um perfil dos idosos quanto os sintomas vestibulares. MÉTODOS: fizeram parte da amostra 143 pacientes, com faixa etária variando de 60 a 90 anos de idade; todos realizaram o exame otoneurológico. Foram excluídos pacientes idosos com queixa de desequilíbrio e aqueles que apresentaram a queixa de zumbido desacompanhado da tontura. RESULTADOS: o estudo demonstrou que a normorreflexia, em valores absolutos, encontra-se entre 82,3% a 91,2% e os valores relativos são de 93%. Referente aos dados colhidos na anamnese, o que chamou a atenção, foi que do total de pacientes analisados, encontrou-se a tontura acompanhada de zumbido em 69% dos casos e o elevado uso de medicação em pacientes nesta faixa etária. CONCLUSÃO: na população estudada houve um predomínio da tontura acompanhada de zumbido. Em relação à prova calórica, o trabalho demonstrou a alta prevalência de pacientes com valores absolutos e relativos normais.PURPOSE: to accomplish the study of caloric testing in senior patients with dizziness, accompanied or not of with buzzing. METHODS: 143 patients were analyzed with age varying from 60 to 90 years; all of them did an otoneurologic evaluation. Senior patients with unbalance complaints and with buzzing unaccompanied with dizziness were excluded from this study. RESULTS: 82.3% to 91.2% of the patients obtained normoreflexia in absolute values and over 93% obtained normal results in relative values. Referring to the data obtained in the anamnesis, what got attention was 69% of dizziness accompanied with buzzing. And the high medication of the patients in this age group. CONCLUSION: there was a prevalence of dizziness accompanied with buzzing in the studied population. Concerning the caloric testing, the study demonstrated the high prevalence of patients with normal absolute and

  19. Dietary restriction with and without caloric restriction for healthy aging [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Changhan Lee

    2016-01-01

    Full Text Available Caloric restriction is the most effective and reproducible dietary intervention known to regulate aging and increase the healthy lifespan in various model organisms, ranging from the unicellular yeast to worms, flies, rodents, and primates. However, caloric restriction, which in most cases entails a 20–40% reduction of food consumption relative to normal intake, is a severe intervention that results in both beneficial and detrimental effects. Specific types of chronic, intermittent, or periodic dietary restrictions without chronic caloric restriction have instead the potential to provide a significant healthspan increase while minimizing adverse effects. Improved periodic or targeted dietary restriction regimens that uncouple the challenge of food deprivation from the beneficial effects will allow a safe intervention feasible for a major portion of the population. Here we focus on healthspan interventions that are not chronic or do not require calorie restriction.

  20. Determinación del calor de fraguado de cemento por icrocalorimetría

    Directory of Open Access Journals (Sweden)

    Liliana Girlado G.

    2010-07-01

    Full Text Available Se determina el calor de fraguado del cemento Río Claro tipo III (Río Claro, Antioquia, Colombia por microcalorimetría de conducción de calor; así como también los efectos de la glucosa y de la sacarosa en el proceso de fraguado de este material. Al emplear 0,15 y 0,05% ( % en peso de estos aditivos en la preparación de las pastas, se observan retardos considerables en el fraguado de las mismas. Los aditivos también modifican el calor de fraguado: la pasta libre de estos presenta un valor de 38,03 J/g en tanto que la adición de glucosa y sacarosa producen valores menores, excepto en el caso de la sacarosa al 0,05% donde se observa un efecto térmico de 55.80 J/s,

  1. Magneto-Caloric Effect of Gd5Si2Ge2Compounds under Different Processing Conditions

    Institute of Scientific and Technical Information of China (English)

    Zeng Hong; Yue Ming; Niu Peili; Zhang Jiuxing

    2004-01-01

    The magneto-caloric effect of Gd5 Si2Ge2 compounds produced by various techniques is investigated in terms of their magnetization behaviors in the magnetic field from 0 to 2.0 T.The studied materials include arc-melted, annealed and sintered alloys.The results demonstrate that the Gd5Si2Ge2 alloys obtained under different processing conditions possess distinct magneto-caloric effect due to their various microstructures.Proper annealing treatment can enhance the magneto-caloric effect of the alloy remarkably.While the sintered alloy bears relatively lower value of magnetic entropy change ( △ SM) than arc-melted one.The magnetic entropy change of the annealed Gd5 Si2Ge2 alloy arrives the arrives the maximum value of - △SM = 15.29 J· kg-1· K-1 for magnetic field change under 2.0 T in the present work.

  2. Efecte de l'estrès per calor en cabres productores de llet

    OpenAIRE

    Salama, Ahmed A. K.

    2015-01-01

    A causa del canvi climàtic, s'espera una major freqüència i intensitat de les onades de calor en el futur. Una investigació ha estudiat els efectes de l'estrès per calor sobre la producció de cabres lleteres de raça Murciano-Granadina i els efectes de l'addició de l'oli de soja i del propilenglicol a la seva dieta. Els resultats mostren diferències evidents en les característiques de la llet de les cabres sotmeses a estrès per calor, així com beneficis de l'ús d'oli de soja per millorar les p...

  3. Transient simulation of molten salt central receiver

    Science.gov (United States)

    Doupis, Dimitri; Wang, Chuan; Carcorze-Soto, Jorge; Chen, Yen-Ming; Maggi, Andrea; Losito, Matteo; Clark, Michael

    2016-05-01

    Alstom is developing concentrated solar power (CSP) utilizing 60/40wt% NaNO3-KNO3 molten salt as the working fluid in a tower receiver for the global renewable energy market. In the CSP power generation cycle, receivers undergo a daily cyclic operation due to the transient nature of solar energy. Development of robust and efficient start-up and shut-down procedures is critical to avoiding component failures due to mechanical fatigue resulting from thermal transients, thus maintaining the performance and availability of the CSP plant. The Molten Salt Central Receiver (MSCR) is subject to thermal transients during normal daily operation, a cycle that includes warmup, filling, operation, draining, and shutdown. This paper describes a study to leverage dynamic simulation and finite element analysis (FEA) in development of start-up, shutdown, and transient operation concepts for the MSCR. The results of the FEA also verify the robustness of the MSCR design to the thermal transients anticipated during the operation of the plant.

  4. Transient Ischemic Attack

    Medline Plus

    Full Text Available ... TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood clot blocks an ... a short time. The only difference between a stroke and TIA is that with TIA the blockage ...

  5. Transient Ischemic Attack

    Medline Plus

    Full Text Available ... TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood clot blocks an ... a short time. The only difference between a stroke and TIA is that with TIA the blockage ...

  6. Searches for radio transients

    CERN Document Server

    Bhat, N D R

    2011-01-01

    Exploration of the transient Universe is an exciting and fast-emerging area within radio astronomy. Known transient phenomena range in time scales from sub-nanoseconds to years or longer, thus spanning a huge range in time domain and hinting a rich diversity in their underlying physical processes. Transient phenomena are likely locations of explosive or dynamic events and they offer tremendous potential to uncover new physics and astrophysics. A number of upcoming next-generation radio facilities and recent advances in computing and instrumentation have provided a much needed impetus for this field which has remained a relatively uncharted territory for the past several decades. In this paper we focus mainly on the class of phenomena that occur on very short time scales (i.e. from $\\sim$ milliseconds to $\\sim$ nanoseconds), known as {\\it fast transients}, the detections of which involve considerable signal processing and data management challenges, given the high time and frequency resolutions required in the...

  7. Transient Ischemic Attack

    Medline Plus

    Full Text Available ... Ischemic Attack TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood clot blocks an artery for a short time. The only difference between a stroke ...

  8. Absence of rotation perception during warm water caloric irrigation in some seniors with postural instability

    Directory of Open Access Journals (Sweden)

    Elodie eChiarovano

    2016-01-01

    Full Text Available Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied.Twenty senior subjects were included in the study separated in two groups: 10 seniors reporting postural instability (PI and exhibiting absence of vestibular perception when they tested with caloric stimulation and 10 sex and age-matched seniors with no such problems (controls. We assessed vestibular perception on a binary rating scale during the warm irrigation of the caloric test. The function of the various vestibular receptors was assessed using video-head impulse test (vHIT, caloric tests, and cervical and ocular VEMPs. The Equitest was used to evaluate balance. No horizontal canal dysfunction assessed using both caloric test and vHIT was detected in either group. No significant difference was detected between PI and control groups for the peak SPV of caloric induced ocular nystagmus or for the HVOR gain. All of the controls perceived rotation when the maximal SPV during warm irrigation was equal to or greater than 15°/s. None of the subjects in the PI group perceived rotation even while the peak SPV exceeded 15°/s, providing objective evidence of normal peripheral horizontal canal function. All of the PI group had abnormal Equitest results, particularly in the two last conditions.These investigations show for the first time that vestibular perception can be absent during a caloric test despite normal horizontal canal function. We call this dissociation vestibular neglect. Patients with poor vestibular perception may not be aware of postural perturbations and so will not correct for them. Thus, falls in the elderly may result, amongst other factors, from a

  9. Aprofitant cada engruna de calor : el Tub Verd de Mataró

    OpenAIRE

    Alerm, Llorenç

    2012-01-01

    La calor residual de diverses infraestructures mediambientals permet distribuir calor i fred al seu entorn urbà. Es tracta d’un aprofitament energètic que redueix contaminació, emissions de CO2 i importacions de combustible. Una estratègia que fa anys que funciona a diversos països del món: al centre i nord d’Europa fa temps que hi està força estesa, i més recentment ha arribat aquí, amb iniciatives com la del Tub Verd de Mataró.

  10. Modelamiento y simulación de tubo de calor de alta temperatura

    OpenAIRE

    Guerra del Río, César Fabián

    2013-01-01

    Resumen: La tecnología de tubos de calor de alta temperatura permite recuperar la energía residual de procesos industriales que día a día se ven obligados a comprometerse en la solución de importantes limitaciones como la contaminación de gases efluentes, perdida deliberada de energía a los alrededores, limitación en el espacio físico para mejorar el proceso y aumento indiscriminado de los costos de inversión. Sin embargo, los tubos de calor de alta temperatura, presentan limitaciones en su f...

  11. Modelamiento y simulación de un tubo de calor de alta temperatura

    OpenAIRE

    Guerra del Río, César Fabián

    2013-01-01

    Resumen: La tecnología de tubos de calor de alta temperatura permite recuperar la energía residual de procesos industriales que día a día se ven obligados a comprometerse en la solución de importantes limitaciones como la contaminación de gases efluentes, perdida deliberada de energía a los alrededores, limitación en el espacio físico para mejorar el proceso y aumento indiscriminado de los costos de inversión. Sin embargo, los tubos de calor de alta temperatura, presentan limitaciones en su f...

  12. Ten-Year Trends in Children’s Caloric-Beverage Consumption and Behavioral Intent

    OpenAIRE

    Carnot MJ; Sutliffe JT; Palmer. SE; Elliott E

    2015-01-01

    Soft drinks, fruit juice and milk are the most common caloric-beverages consumed by adolescents and teens. We report the ten-year trends in the percentage of daily calories consumed in the form of caloric-beverages from a broad sample of fifth-grade students in the United States. This is a major area of concern related to dietary quality and body weight amongst children. The study was conducted from 2001-2011 through the Healthy Hearts for Kids (HH4K) online instructional ...

  13. Second Law Violation By Magneto-Caloric Effect Adiabatic Phase Transition of Type I Superconductive Particles

    Directory of Open Access Journals (Sweden)

    Peter Keefe

    2004-03-01

    Full Text Available Abstract: The nature of the thermodynamic behavior of Type I superconductor particles, having a cross section less than the Ginzburg-Landau temperature dependent coherence length is discussed for magnetic field induced adiabatic phase transitions from the superconductive state to the normal state. Argument is advanced supporting the view that when the adiabatic magneto-caloric process is applied to particles, the phase transition is characterized by a decrease in entropy in violation of traditional formulations of the Second Law, evidenced by attainment of a final process temperature below that which would result from an adiabatic magneto-caloric process applied to bulk dimensioned specimens.

  14. Combined caloric effects in a multiferroic Ni-Mn-Ga alloy with broad refrigeration temperature region

    Science.gov (United States)

    Hu, Yong; Li, Zongbin; Yang, Bo; Qian, Suxin; Gan, Weimin; Gong, Yuanyuan; Li, Yang; Zhao, Dewei; Liu, Jian; Zhao, Xiang; Zuo, Liang; Wang, Dunhui; Du, Youwei

    2017-04-01

    Solid-state refrigeration based on the caloric effects is promising to replace the traditional vapor-compressing refrigeration technology due to environmental protection and high efficiency. However, the narrow working temperature region has hindered the application of these refrigeration technologies. In this paper, we propose a method of combined caloric, through which a broad refrigeration region can be realized in a multiferroic alloy, Ni-Mn-Ga, by combining its elastocaloric and magnetocaloric effects. Moreover, the materials' efficiency of elastocaloric effect has been greatly improved in our sample. These results illuminate a promising way to use multiferroic alloys for refrigeration with a broad refrigeration temperature region.

  15. Análisis estructural de un intercambiador de calor de un reactor avanzado

    OpenAIRE

    García Merino, Carlos

    2008-01-01

    El objetivo fundamental de este proyecto consiste en el estudio estructural de un intercambiador de calor de un reactor avanzado de Generación VI. Este intercambiador de calor es el condensador PCCS (Passive Containment Cooling System), sistema de seguridad de una central nuclear ESBWR. El análisis estructural del condensador se ha realizado analítica y numéricamente. El cálculo analítico utiliza expresiones obtenidas del código ASME, para determinar tensiones por presiones internas. Y el cál...

  16. Changes of endolymphatic pressure in the semicircular canal of pigeon by caloric stimulation

    Science.gov (United States)

    Wada, Y.; Suzuki, H.; Watanabe, S.

    1994-08-01

    It gets into difficult to explain the mechanism of caloric nystagmus only by convection theory from results of microgravity experiments. One of the other theories is an occurrence of a relative volume change due to a temperature change. Since the volume change must lead to a pressure change after caloric stimulation, we tried to measure the ampulla pressure of the horizontal semicircular canal in pigeons (Columba livia) using an improved servo micropipette system. The main result was that the ampulla pressure increased by cooling and decreased by heating. The changes of the ampulla pressure depended on the temperature change but were not influenced by the pigeon's head position.

  17. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas

    OpenAIRE

    2015-01-01

    The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg) participate in this study during a period of weight maintenance (baseline) and after 7 days of caloric restriction (CR). All subjects performed the Special Judo Fitness Test (SJFT) during the two conditions. Values for nutrient intakes were ...

  18. Caloric Intake From Fast Food Among Children and Adolescents in the United States, 2011-2012.

    Science.gov (United States)

    Vikraman, Sundeep; Fryar, Cheryl D; Ogden, Cynthia L

    2015-09-01

    Consumption of fast food has been linked to weight gain in adults (1). Fast food has also been associated with higher caloric intake and poorer diet quality in children and adolescents (2). From 1994 through 2006, caloric intake from fast food increased from 10% to 13% among children aged 2-18 years (3). This report presents the most recent data on the percentage of calories consumed from fast food among U.S. children by sex, age group, race and Hispanic origin, poverty status, and weight status.

  19. Transient multivariable sensor evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Vilim, Richard B.; Heifetz, Alexander

    2017-02-21

    A method and system for performing transient multivariable sensor evaluation. The method and system includes a computer system for identifying a model form, providing training measurement data, generating a basis vector, monitoring system data from sensor, loading the system data in a non-transient memory, performing an estimation to provide desired data and comparing the system data to the desired data and outputting an alarm for a defective sensor.

  20. Transient multivariable sensor evaluation

    Science.gov (United States)

    Vilim, Richard B.; Heifetz, Alexander

    2017-02-21

    A method and system for performing transient multivariable sensor evaluation. The method and system includes a computer system for identifying a model form, providing training measurement data, generating a basis vector, monitoring system data from sensor, loading the system data in a non-transient memory, performing an estimation to provide desired data and comparing the system data to the desired data and outputting an alarm for a defective sensor.

  1. Estimativa do fluxo de calor latente pelo balanço de energia em cultivo protegido de pimentão Estimate of the latent heat flux by the energy balance in protected cultivation of sweet pepper

    Directory of Open Access Journals (Sweden)

    Antonio Ribeiro da Cunha

    2002-06-01

    Full Text Available O objetivo deste trabalho foi caracterizar e relacionar a radiação líquida com o calor latente equivalente, em mm de água, nos cultivos protegido e de campo, na cultura de pimentão. O experimento foi feito em Botucatu, SP. A estimativa do fluxo de calor latente foi feita pelo método do balanço de energia, por meio da razão de Bowen. Foram feitas medidas instantâneas da radiação líquida (Rn, dos fluxos convectivos de calor latente (LE e sensível (H, do fluxo de calor no solo (G, e dos gradientes psicrométricos sobre a cultura. O cultivo protegido, apesar de receber menor quantidade de radiação solar global, foi mais eficiente na conversão da radiação líquida disponível em matéria seca total e na produtividade de frutos. No balanço de energia, o cultivo protegido apresentou razões G/Rn e LE/Rn inferiores e H/Rn superior, com um fluxo de calor latente, equivalente em milímetros, 45,43% menor que no cultivo no campo. Apresentou, ainda, menor quantidade de radiação líquida disponível e menores perdas de energia, mostrando-se mais eficiente no uso da água.The aim of this work was to characterize and bring into relationship the net radiation with the latent heat flux equivalent to water mm, in sweet pepper crops in the field and in protected cultivation. The estimate of latent heat flux was made by the energy balance method through the Bowen ratio. Instantaneous measures were made of net radiation (Rn, sensitive (H and latent (LE heat fluxes, heat flux into the soil (G, and of psychrometers gradients in the crop canopy. In protected cultivation, the conversion of the available net radiation in total dry matter and fruit productivity was more efficient than in the field, in spite of lower amounts of global solar radiation received by the crop. Ratios of G/Rn and LE/Rn were lower, and that of H/Rn was higher in protected cultivation, with an equivalent latent heat flux in millimeters, 45.43% lower than that determined in the

  2. Effect of Replacing Sugar with Non-Caloric Sweeteners in Beverages on the Reward Value after Repeated Exposure

    NARCIS (Netherlands)

    Griffioen-Roose, S.; Smeets, P.A.M.; Weijzen, P.L.G.; Rijn, van I.; Bosch, van den I.; Graaf, de C.

    2013-01-01

    Background: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. Objective: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty d

  3. Thermoregulatory, Cardiovascular, and Metabolic Responses to Mild Caloric Restriction in the Brown Norway Rat

    Science.gov (United States)

    Caloric restriction (CR) has been demonstrated to prolong the life span of a variety of species. CR-induced reduction in core temperature (Tc) is considered a key mechanism responsible for prolonging life span in rodents; however, little is known on the regulation of CR-induced h...

  4. Effects of Caloric Restriction on Cardiac Oxidative Stress and Mitochondrial Bioenergetics: Potential Role of Cardiac Sirtuins

    Directory of Open Access Journals (Sweden)

    Ken Shinmura

    2013-01-01

    Full Text Available The biology of aging has not been fully clarified, but the free radical theory of aging is one of the strongest aging theories proposed to date. The free radical theory has been expanded to the oxidative stress theory, in which mitochondria play a central role in the development of the aging process because of their critical roles in bioenergetics, oxidant production, and regulation of cell death. A decline in cardiac mitochondrial function associated with the accumulation of oxidative damage might be responsible, at least in part, for the decline in cardiac performance with age. In contrast, lifelong caloric restriction can attenuate functional decline with age, delay the onset of morbidity, and extend lifespan in various species. The effect of caloric restriction appears to be related to a reduction in cellular damage induced by reactive oxygen species. There is increasing evidence that sirtuins play an essential role in the reduction of mitochondrial oxidative stress during caloric restriction. We speculate that cardiac sirtuins attenuate the accumulation of oxidative damage associated with age by modifying specific mitochondrial proteins posttranscriptionally. Therefore, the distinct role of each sirtuin in the heart subjected to caloric restriction should be clarified to translate sirtuin biology into clinical practice.

  5. Resource availability hypothesis: Perceived financial and caloric status affect individuals' height preferences for potential partners.

    Science.gov (United States)

    Sun, Qingzhou; Lou, Liandi; Lu, Jingyi; Wang, Xiaoming; Zhong, Jun; Tan, Xuyun; Li, Yanxia; Liu, Yongfang

    2016-10-01

    Height is an important concern in human mate choices. Prior research indicates that people who live in areas with abundant resources differ from those who live in areas with scarce resources regarding height preferences. Based on a health-maximizing principle, we propose a resource availability account for such differences. Compared with women's height preferences, men's height preferences are hypothesized to be more dependent on either financial or caloric resource availability. Specifically, taller females would be more preferred by males who are poor in resources than those who are rich in resources. Results from three studies supported these hypotheses. In Study 1, men from remote areas of China who had lower family income preferred taller women more than those from eastern China who had higher family income. In Study 2, men who were financially dissatisfied preferred taller women more than those who were financially satisfied. In Study 3, men with low caloric status preferred taller women more than men with high caloric status. In addition, women's height preferences in Studies 1, 2 and 3 were less determined by resource availability. These findings suggest that height preferences are changeable, depending on financial or caloric status.

  6. SIRT2 deacetylates FOXO3a in response to oxidative stress and caloric restriction

    Science.gov (United States)

    The sirtuin family of nicotinamide adenine dinucleotide-dependent (NAD) deacetylases plays an important role in aging and metabolic regulation. In yeast, the Sir2 gene and its homolog Hst2 independently mediate the action of caloric restriction on lifespan extension. The mammalian Sir2 ortholog, SIR...

  7. A critique of Sadi Carnot's work and a mathematical theory of the caloric

    CERN Document Server

    Dass, N D Hari

    2013-01-01

    In this work, Sadi Carnot;s fundamental work is critically examined, and contrasted with modern thermodynamics. A mathematical theory of his work is given on the basis of the observation that in caloric theory dQ is a perfect differential.

  8. Timing versus caloric goal in nutritional therapy for critically ill patients

    Directory of Open Access Journals (Sweden)

    Oellen Stuani Franzosi

    Full Text Available Introduction: Enteral nutrition is an important therapy for severely critically ill patients. The timing and amount of energy have been highly debated. Objective: The aim of the present study was to directly compare the timing and the caloric targets in critically ill patients. Methods: Retrospective cohort study conducted at a single center, comparing timing and caloric goal for critically ill patients. Patients were stratified according to the start of nutritional therapy (24, 48, or more than 48 h and the amount of energy delivered (target adequacy of previously calculated percentage in the first week. Statistical analysis was performed using parametric and non-parametric tests for independent samples and logistic regression. The results were expressed as mean ± standard deviation or incidence and percentage. Results and discussion: There were no differences in major clinical outcomes in relation to the achievement of percentage of caloric goal at the end of the first week of the study. The beginning of caloric intake on the first day of hospitalization was associated with reduced mortality in the intensive care unit, but not with hospital mortality. The strategy of an early and limited amount of calories seems to be associated with a better outcome. Prospective studies evaluating and comparing these strategies are recommended.

  9. Desenvolvimento de um simulador com interface amigável de um módulo didático de transferência de calor em aletas

    Directory of Open Access Journals (Sweden)

    Welington Pereira Santos

    2001-05-01

    Full Text Available Neste trabalho, foi implementado um simulador com interface amigável de um módulo didático clássico de transferência de calor em aletas, utilizado em várias instituições de ensino superior. O simulador foi desenvolvido em linguagem orientada a objetos DELPHI e apresenta um formulário de entrada de dados interativo em uma janela, enquanto o resultado da simulação é visualizado na forma gráfica. O simulador possui um banco de correlações de literatura para a estimação das propriedades físicas e dos parâmetros térmicos do modelo

  10. Transient lingual papillitis.

    Science.gov (United States)

    Kornerup, Ida M; Senye, Mireya; Peters, Edmund

    2016-01-01

    A case of recurrent, clinically innocuous, but painful papules involving the tongue dorsum of a 25-year-old man is presented. The lesions were interpreted to represent a transient lingual papillitis. This a poorly understood, but benign and self-limited condition involving the tongue fungiform papillae, which does not appear to be widely recognized.

  11. Transient Heat Conduction

    DEFF Research Database (Denmark)

    Rode, Carsten

    1998-01-01

    Analytical theory of transient heat conduction.Fourier's law. General heat conducation equation. Thermal diffusivity. Biot and Fourier numbers. Lumped analysis and time constant. Semi-infinite body: fixed surface temperature, convective heat transfer at the surface, or constant surface heat flux...

  12. Transient tachypnea - newborn

    Science.gov (United States)

    ... or reabsorbing it. The first few breaths a baby takes after delivery fill the lungs with air and help to ... goes away within 24 to 48 hours after delivery. In most cases, babies who have had transient tachypnea have no further ...

  13. On Detecting Transients

    CERN Document Server

    Belanger, G

    2013-01-01

    Transient phenomena are interesting and potentially highly revealing of details about the processes under observation and study that could otherwise go unnoticed. It is therefore important to maximise the sensitivity of the method used to identify such events. In this article we present a general procedure based on the use of the likelihood function for identifying transients that is particularly suited for real-time applications because it requires no grouping or pre-processing of the data. The method is optimal in the sense that all the information that is available in the data is used in the statistical decision making process, and is suitable for a wide range of applications. We here consider those most common in astrophysics which involve searching for transient sources, events or features in images, time series, energy spectra and power spectra, and demonstrate the use of the method in the cases of a transient in a time series or in a power spectrum. We derive a fit statistic that is ideal for fitting a...

  14. The LOFAR Transients Pipeline

    NARCIS (Netherlands)

    Swinbank, J.; Staley, T.; Molenaar, G.; Rol, E.; Rowlinson, A.; Scheers, L.H.A.; Spreeuw, H.; Bell, M.E.; Broderick, J.; Carbone, D.; Garsden, H.; Horst, A. van der; Law, C.J.; Wise, M.W.; Breton, R.P.; Cendes, Y.; Corbel, S.; Eisloeffel, J.; Falcke, H.; Fender, R.P.; Griessmeier, J.-M.; Hessels, J.W.T.; Stappers, B.W.; Stewart, A.; Wijers, R.A.M.J.; Wijnands, R.; Zarka, P.

    2015-01-01

    Current and future astronomical survey facilities provide a remarkably rich opportunity for transient astronomy, combining unprecedented fields of view with high sensitivity and the ability to access previously unexplored wavelength regimes. This is particularly true of LOFAR, a recently-commissione

  15. Coeficientes de transferencia de calor y pérdida de eficiencia en intercambiadores de calor de placas durante el enfriamiento del licor amoniacal

    Directory of Open Access Journals (Sweden)

    Enrique Torres-Tamayo

    2011-10-01

    Full Text Available En la planta de Recuperación de Amoniaco de la empresa niquelera Ernesto Che Guevara la pérdida de eficiencia del proceso de enfriamiento del licor amoniacal, mediante el uso de intercambiadores de calor de placas, se asocia a la incorrecta estimación de los coeficientes de transferencia de calor y la acumulación de incrustaciones en la superficie de intercambio; lo anterior incrementa el consumo de agua, la energía disponible en el sistema y los costos de mantenimiento. Se realizó una investigación en un intercambiador de calor de placas, con el objetivo de determinar los coeficientes de transferencia y la influencia de las incrustaciones en la pérdida de eficiencia de la instalación. Mediante un procedimiento iterativo se determinó la ecuación del número de Nusselt y su dependencia con el Reynolds y Prandtl, para ello se utilizó un diseño experimental multifactorial y mediciones de los parámetros de trabajo de la instalación en función del tiempo. Los resultados predicen el conocimiento de los coeficientes para el cálculo del número de Nusselt, con los valores de Reynolds y Prandtl, para ambos fluidos (licor amoniacal y agua. Los valores de los coeficientes del licor son inferiores, ello se debe a la presencia de componentes gaseosos. La comparación con resultados de otros autores muestra correspondencia con los de Thonon. Se recomienda la limpieza y mantenimiento de la instalación en un período de 27 días debido a la reducción de la eficiencia térmica hasta valores inferiores al 70 %.

  16. Compressive Transient Imaging

    KAUST Repository

    Sun, Qilin

    2017-04-01

    High resolution transient/3D imaging technology is of high interest in both scientific research and commercial application. Nowadays, all of the transient imaging methods suffer from low resolution or time consuming mechanical scanning. We proposed a new method based on TCSPC and Compressive Sensing to achieve a high resolution transient imaging with a several seconds capturing process. Picosecond laser sends a serious of equal interval pulse while synchronized SPAD camera\\'s detecting gate window has a precise phase delay at each cycle. After capturing enough points, we are able to make up a whole signal. By inserting a DMD device into the system, we are able to modulate all the frames of data using binary random patterns to reconstruct a super resolution transient/3D image later. Because the low fill factor of SPAD sensor will make a compressive sensing scenario ill-conditioned, We designed and fabricated a diffractive microlens array. We proposed a new CS reconstruction algorithm which is able to denoise at the same time for the measurements suffering from Poisson noise. Instead of a single SPAD senor, we chose a SPAD array because it can drastically reduce the requirement for the number of measurements and its reconstruction time. Further more, it not easy to reconstruct a high resolution image with only one single sensor while for an array, it just needs to reconstruct small patches and a few measurements. In this thesis, we evaluated the reconstruction methods using both clean measurements and the version corrupted by Poisson noise. The results show how the integration over the layers influence the image quality and our algorithm works well while the measurements suffer from non-trival Poisson noise. It\\'s a breakthrough in the areas of both transient imaging and compressive sensing.

  17. Prácticas de Física: Equivalente en agua de un calorímetro

    OpenAIRE

    Beléndez,Augusto; Bernabeu, Guillermo; Vera Guarinos, Jenaro; Pastor Antón, Carlos; Martín García, Agapito

    1988-01-01

    Esta práctica de laboratorio tiene como objetivo el cálculo del equivalente en agua de un calorímetro con su error, familiarizarse con el uso del mismo y del termómetro. Para el desarrollo de esta práctica se dispone de un calorímetro lleno de agua en el que se ha colocado una resistencia interna. Se hace circular una corriente por la resistencia, de manera que la potencia que disipa la resistencia se convierte en potencia calorífica, por efecto Joule, calentando por un lado el agua en el int...

  18. Líneas de calor para convección natural en cavidades cerradas: Tres casos de estudio

    OpenAIRE

    J.G. Cervantes de Gortari; J.C. Torchia-Núñez; J.A. Serrano-Gutiérrez; A. Muñoz-Barrera; E. Guzmán-Vázquez; F. Gutiérrez-Coria; O. Chávez-López; I. Rosas-Yescas; E. Martínez-Galván

    2010-01-01

    Se presenta la técnica de visualización de líneas de calor para tres casos específicos de convección natural en cavidades cerradas. El objetivo es mostrar las ventajas de visualizar la transferencia de calor para un fluido en movimiento en lugar del uso de isotermas. Los tres casos de estudio se tomaron arbitraria mente por ser casos estudiados experimental y numéricamente, donde se conocen los campos de velocidad y temperatura, también por ser casos donde el régimen de trasferencia de calor ...

  19. Research on heat pumps in Mexico operating with geothermal energy and waste heat; Investigacion sobre bombas de calor en Mexico operando con energia geotermica y calor de desecho

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Gutierrez, A; Barragan-Reyes, R.M; Arellano-Gomez, V [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: aggarcia@iie.org.mx

    2008-01-15

    The Instituto de Investigaciones Electricas and the Comision Federal de Electricidad have done research and development (R&D) on heat pumps (HP) in past years. Tested systems include mechanical compression, absorption and heat-transformers. The main R&D aspects on HP are briefly described, and also a more detailed description about three of the main studies is presented: (a) a mechanical compression HP of the water-water type operated with low-pressure geothermal steam at the Los Azufres; Mich., geothermal field, and designed for purification of brine; (b) an absorption HP for cooling and refrigeration operating with ammonia-water and low-enthalpy geothermal energy, which was tested in the Los Azufres and Cerro Prieto, BC, geothermal fields; and (c) a heat-transformer by absorption-Absorption Heat Pump Type II-tested to assess the performance of several ternary solutions as work fluids. Plans exist to install and test a geothermal heat pump at Cerro Prieto or Mexicali, BC. [Spanish] El Instituto de Investigaciones Electricas y la Comision Federal de Electricidad han realizado trabajo de investigacion y desarrollo (I&D) sobre bombas de calor (BC) en el pasado. Los sistemas probados incluyen compresion mecanica, absorcion y transformadores termicos. Este trabajo describe brevemente los principales aspectos de I&D sobre bombas de calor en forma general, y se da una descripcion mas detallada de tres de los principales estudios: (a) una BC por compresion mecanica tipo agua-agua disenada para purificacion de salmueras operando con vapor geotermico de baja presion en el campo geotermico de Los Azufres, Mich.; (b) una BC por absorcion para enfriamiento y refrigeracion operando con amoniaco-agua y energia geotermica de baja entalpia, la cual fue probada en los campos geotermicos de Los Azufres y Cerro Prieto, BC; y (c) un transformador termico por absorcion -llamado Bomba de Calor por Absorcion Tipo II--, el cual fue probado para evaluar el comportamiento de diversas

  20. E-4031 enhanced Ca2+ transient and ventricular myocytes contraction via reverse mode Na+/Ca2+ exchange in normal and hypertrophic rats%E-4031通过反向钠钙交换增加正常和心肌肥厚大鼠心肌细胞钙瞬变和收缩

    Institute of Scientific and Technical Information of China (English)

    崔香丽; 赵录英; 吴博威

    2002-01-01

    AIM: To study the effects of N-[4-[[1-[2-(6-methyl-2-pyridinyl)ethyl]-4-piperidinyl]carbonyl]phenyl]methanesulfonamide dihydrochloride dihydrate (E-4031), a specific Ikblocker, on Ca2+ transient and cell contractionof normal and hypertrophied rat ventricular myocytes. METHODS: Electrically triggered Ca2+ transient and cellshortening were measured simultaneously using the Ion Imaging System with charge coupled digital (CCD) camera.REESULTS: E-4031 (10μmol/L) increased Ca2+ transient and cell shortening from (210+49) and (3.0-x-0.8) Um to(245±47) and (3.6+1.0) μm, respectively (P<0.05) in normal cardiomyocytes and from (196±54) and (3.0+1.3)μm to (240-±49) and (3.6+1.3) μm respectively (P<0.05) in hypertrophied cardiomyocytes, while did not changecalcium sensitivity in both groups. KB-R7943 completely blocked the activating effects induced by E-4031 in bothof normal and hypertrophied cardiomyocytes. Nicardipine did not block the increasing effects of E-4031.CCONCLUSION: E-4031 increased Ca2+ transient and cell contraction via stimulating reverse mode of Na+/Ca2+exchange while without influencing calcium sensitivity. These effects were more notable in hypertrophiedcardiomyocytes than in normal myocytes.%目的:观察Ik阻断剂E一4031对正常和心肌肥厚大鼠钙瞬变和细胞收缩的影响.方法:应用带CCD Cam-era的离子影象分析系统(Ion Imaging System)测定离体大鼠心肌细胞钙瞬变和细胞长度.结果:E-4031(10Umol/L)分别使正常组钙瞬变和细胞缩短从对照组的(210±49)和(3.0±0.8)u皿增加到(245±47)和(3.6±1.0)um(P<0.05),使心肌肥厚组钙瞬变和细胞缩短分别从对照组的(196±54)和(3.0±1.3)um增加到(240±49)和(3.6±1.3)um(p<0.05),而对钙敏感性无显著影响.KB-R7943可完全阻断正常组和肥厚组心肌细胞由E-4031诱导的激动作用.尼卡地平不能阻断E-4031的增加作用.结论:E一4031可通过刺激反向钠钙交换增加正常和心肌肥厚大鼠心肌细胞钙瞬变

  1. Ultrafast triggered transient energy storage by atomic layer deposition into porous silicon for integrated transient electronics

    Science.gov (United States)

    Douglas, Anna; Muralidharan, Nitin; Carter, Rachel; Share, Keith; Pint, Cary L.

    2016-03-01

    porous silicon, dissolution tests for 0.1 M and 0.01 M NaOH trigger solutions, EIS analysis for VOx coated devices, and EDS compositional analysis of VOx. (ii) Video showing transient behavior of integrated VOx/porous silicon scaffolds. See DOI: 10.1039/c5nr09095d

  2. DISEÑO Y CONSTRUCCIÓN DE PROTOTIPO PARA MEDICIÓN DE FLUJO DE CALOR APLICANDO CALORIMETRÍA DIRECTA: SENSADO POR FLUJO DE CALOR

    Directory of Open Access Journals (Sweden)

    OSCAR CADENA

    2008-01-01

    Full Text Available El presente artículo describe el diseño de un prototipo inalámbrico para la medición de flujo de calor, que permita a futuro aplicar el método de calorimetría directa por gradiente de flujo de calor en el área de la electrónica médica. Esta técnica se desarrolla gracias al avance y creación de sensores que permiten medir este tipo de variables, y se postula como una alternativa a las formas de medición utilizadas actualmente, presentando mejoras en su desempeño y costo. Los resultados obtenidos luego de efectuar la calibración del equipo permiten inferir que la técnica propuesta se adapta de forma eficiente y puede utilizarse como un sustituto significativamente más ventajoso comparado con los métodos existentes en la actualidad y aplicados en el seguimiento metabólico de personas.

  3. (Magneto)caloric refrigeration: is there light at the end of the tunnel?

    Science.gov (United States)

    Pecharsky, Vitalij K; Cui, Jun; Johnson, Duane D

    2016-08-13

    Caloric cooling and heat pumping rely on reversible thermal effects triggered in solids by magnetic, electric or stress fields. In the recent past, there have been several successful demonstrations of using first-order phase transition materials in laboratory cooling devices based on both the giant magnetocaloric and elastocaloric effects. All such materials exhibit non-equilibrium behaviours when driven through phase transformations by corresponding fields. Common wisdom is that non-equilibrium states should be avoided; yet, as we show using a model material exhibiting a giant magnetocaloric effect, non-equilibrium phase-separated states offer a unique opportunity to achieve uncommonly large caloric effects by very small perturbations of the driving field(s).This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'.

  4. Mechanism-Based Modeling of Gastric Emptying Rate and Gallbladder Emptying in Response to Caloric Intake

    DEFF Research Database (Denmark)

    Guiastrennec, B; Sonne, David Peick; Hansen, M

    2016-01-01

    Bile acids released postprandially modify the rate and extent of absorption of lipophilic compounds. The present study aimed to predict gastric emptying (GE) rate and gallbladder emptying (GBE) patterns in response to caloric intake. A mechanism-based model for GE, cholecystokinin plasma concentr......Bile acids released postprandially modify the rate and extent of absorption of lipophilic compounds. The present study aimed to predict gastric emptying (GE) rate and gallbladder emptying (GBE) patterns in response to caloric intake. A mechanism-based model for GE, cholecystokinin plasma...... concentrations were not predictive of GBE, and an alternative model linking the nutrients amount in the upper intestine to GBE was preferred. Relative to fats, the potency on GBE was 68% for proteins and 2.3% for carbohydrates. The model predictions were robust across a broad range of nutritional content and may...

  5. Equipos de transferencia de calor: una guía de estudio

    OpenAIRE

    Carrero Mantilla, Javier Ignacio

    2008-01-01

    La transferencia de calor es una ciencia básica de la ingeniería, que se incluye en los planes de estudio en muchas de las ramas de la profesión: mecánica, química, de alimentos, entre otras. En general, es posible dividir el estudio de la transferencia de calor en dos partes: la primera comprende los principios básicos del transporte de energía y de materia, mientras que la segunda se dedica al diseño y a la evaluación de equipos. El libro está distribuido en seis capítulos y dos apéndice...

  6. Non-caloric artificial sweeteners and the microbiome: findings and challenges

    Science.gov (United States)

    Suez, Jotham; Korem, Tal; Zilberman-Schapira, Gili; Segal, Eran; Elinav, Eran

    2015-01-01

    Non-caloric artificial sweeteners (NAS) are common food supplements consumed by millions worldwide as means of combating weight gain and diabetes, by retaining sweet taste without increasing caloric intake. While they are considered safe, there is increasing controversy regarding their potential ability to promote metabolic derangements in some humans. We recently demonstrated that NAS consumption could induce glucose intolerance in mice and distinct human subsets, by functionally altering the gut microbiome. In this commentary, we discuss these findings in the context of previous and recent works demonstrating the effects of NAS on host health and the microbiome, and the challenges and open questions that need to be addressed in understanding the effects of NAS consumption on human health. PMID:25831243

  7. Parental attachment insecurity predicts child and adult high-caloric food consumption.

    Science.gov (United States)

    Faber, Aida; Dubé, Laurette

    2015-05-01

    Eating habits are established early and are difficult to change once formed. This study investigated the role of caregiver-child attachment quality and its associations with high-caloric food consumption in a sample of middle socio-economic status children and adults, respectively. Survey data were collected from an online questionnaire administered separately to 213 (143 girls) children and 216 parents (adult sample; 180 women). Two studies showed that an insecure parental attachment, whether actual (Study 1; children) or recalled (Study 2; adults), significantly and positively predicted high-caloric food consumption in both samples. The present findings highlight the importance of parental attachment and its association with unhealthy eating patterns in children and adults.

  8. Desarrollos instrumentales en microcalorimetría de conducción de calor

    Directory of Open Access Journals (Sweden)

    Liliana Girlado G.

    2010-07-01

    Full Text Available Se presentan aspectos generales de la microcalorimetría de conducción de calor. Se describe el diseño y la operación de microcalorímetros de conducción de calor estático y de flujo construidos en este laboratorio, los cuales fueron calibrados eléctrica y químicamente. Estos equipos se emplean en la caracterización de sólidos porosos por la técnica de calorimetría de inmersión y en la determinación de entalpias de transferencia de solutos; su uso se ilustra con algunos resultados típicos. Se mencionan además otras aplicaciones que se dan actualmente a estos aparatos.

  9. Caloric curve of 8 GeV/c negative pion and antiproton + Au reactions

    CERN Document Server

    Ruangma, A; Martin, E; Ramakrishnan, E; Rowland, D J; Veselsky, M; Winchester, E M; Yennello, S J; Beaulieu, L; Hsi, W C; Kwiatkowski, K K; Lefort, T; Viola, V E; Botvina, A; Korteling, R G; Pienkowski, L; Breuer, H; Gushue, S; Remsberg, L P

    2002-01-01

    The relationship between nuclear temperature and excitation energy of hot nuclei formed by 8 GeV/c negative pion and antiproton beams incident on 197Au has been investigated with the ISiS 4-pidetector array at the BNL AGS accelerator. The double-isotope-ratio technique was used to calculate the temperature of the hot system. The two thermometers used (p/d-3He/4He) and (d/t-3He/4He) are in agreement below E*/A ~ 7 MeV when corrected for secondary decay. Comparison of these caloric curves to those from other experiments shows some differences that may be attributable to instrumentation and analysis procedures. The caloric curves from this experiment are also compared with the predictions from the SMM multifragmentation model.

  10. Mechanism‐Based Modeling of Gastric Emptying Rate and Gallbladder Emptying in Response to Caloric Intake

    Science.gov (United States)

    Sonne, DP; Hansen, M; Bagger, JI; Lund, A; Rehfeld, JF; Alskär, O; Karlsson, MO; Vilsbøll, T; Knop, FK; Bergstrand, M

    2016-01-01

    Bile acids released postprandially modify the rate and extent of absorption of lipophilic compounds. The present study aimed to predict gastric emptying (GE) rate and gallbladder emptying (GBE) patterns in response to caloric intake. A mechanism‐based model for GE, cholecystokinin plasma concentrations, and GBE was developed on data from 33 patients with type 2 diabetes and 33 matched nondiabetic individuals who were administered various test drinks. A feedback action of the caloric content entering the proximal small intestine was identified for the rate of GE. The cholecystokinin concentrations were not predictive of GBE, and an alternative model linking the nutrients amount in the upper intestine to GBE was preferred. Relative to fats, the potency on GBE was 68% for proteins and 2.3% for carbohydrates. The model predictions were robust across a broad range of nutritional content and may potentially be used to predict postprandial changes in drug absorption. PMID:28028939

  11. Non-caloric artificial sweeteners and the microbiome: findings and challenges.

    Science.gov (United States)

    Suez, Jotham; Korem, Tal; Zilberman-Schapira, Gili; Segal, Eran; Elinav, Eran

    2015-01-01

    Non-caloric artificial sweeteners (NAS) are common food supplements consumed by millions worldwide as means of combating weight gain and diabetes, by retaining sweet taste without increasing caloric intake. While they are considered safe, there is increasing controversy regarding their potential ability to promote metabolic derangements in some humans. We recently demonstrated that NAS consumption could induce glucose intolerance in mice and distinct human subsets, by functionally altering the gut microbiome. In this commentary, we discuss these findings in the context of previous and recent works demonstrating the effects of NAS on host health and the microbiome, and the challenges and open questions that need to be addressed in understanding the effects of NAS consumption on human health.

  12. Caloric restriction in lean and obese strains of laboratory rat: effects on body composition, metabolism, growth and overall health

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data related to obese and lean strains of rat commonly used in the laboratory that are calorically restricted and its effects on physiologic parameters (Body...

  13. Coherent Transient Systems Evaluation

    Science.gov (United States)

    1993-06-17

    manuscript is submitted for publication with the understanding that the United States Government is authorized to reproduce and distribute reprints...for governmental purposes. 1.0 Introduction The continuous optical correlator presented here is based on the phenomena of coherent transients, also...Gating the Continuous Processor Programming the continuous processor is accomplished by illuminati , n, the material with ,.’ modulated light pulses: a

  14. The Rapid Transient Surveyor

    Science.gov (United States)

    Baranec, Christoph; Tonry, John; Wright, Shelley; Tully, R. Brent; Lu, Jessica R.; Takamiya, Marianne Y.; Hunter, Lisa

    2016-01-01

    The next decade of astronomy will be dominated by large area surveys (see the detailed discussion in the Astro-2010 Decadal survey and NRC's recent OIR System Report). Ground-based optical transient surveys, e.g., LSST, ZTF and ATLAS and space-based exoplanet, supernova, and lensing surveys such as TESS and WFIRST will join the Gaia all-sky astrometric survey in producing a flood of data that will enable leaps in our understanding of the universe. There is a critical need for further characterization of these discoveries through high angular resolution images, deeper images, spectra, or observations at different cadences or periods than the main surveys. Such follow-up characterization must be well matched to the particular surveys, and requires sufficient additional observing resources and time to cover the extensive number of targets.We describe plans for the Rapid Transient Surveyor (RTS), a permanently mounted, rapid-response, high-cadence facility for follow-up characterization of transient objects on the U. of Hawai'i 2.2-m telescope on Maunakea. RTS will comprise an improved robotic laser adaptive optics system, based on the prototype Robo-AO system (formerly at the Palomar 1.5-m and now at the Kitt Peak 2.2-m telescope), with simultaneous visible and near-infrared imagers as well as a near-infrared integral field spectrograph (R~100, λ = 850 - 1830 nm, 0.15″ spaxels, 8.7″×6.0″ FoV). RTS will achieve an acuity of ~0.07″ in visible wavelengths and automated detection and characterization of astrophysical transients during a sustained observing campaign will yield the necessary statistics to precisely map dark matter in the local universe.

  15. Heat pump for purification of geothermal brines; Bomba de calor para purificacion de salmuera geotermica

    Energy Technology Data Exchange (ETDEWEB)

    Santoyo-Gutierrez, S; Barragan-Reyes, R.M; Holland, F.A [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: rmb@iie.org.mx

    2007-01-15

    Integrated use of geothermal resources is one of the most important goals for the future. Presently geothermal heat pumps offer two benefits: using heat from residual brines and converting these brines into very pure water. Designs and descriptions are presented of an experimental system to purify geothermal brines integrated to an adsorption heat-pump. The system was constructed and tested in the IIE (Institute for Electrical Research) facilities. During the experimental stage, pure water was obtained. Maximum capacity for pure water was 4.3 kg per hour, presenting an Actual Coefficient of Performance (COP)A of 1.4. The results are encouraging to project units at an industrial level for operating with geothermal and/or solar heat. [Spanish] El aprovechamiento integral de los recursos geotermicos en todas sus formas es una de las metas importantes a lograr en los proximos anos. Hoy en dia, el uso de las bombas de calor en la geotermia ofrece un doble beneficio: aprovechan el calor de los fluidos de desecho y tienen la capacidad de transformar la salmuera geotermica en agua de alta pureza. Se presenta el diseno y descripcion de un sistema experimental para purificacion de salmuera geotermica integrado a una bomba de calor por absorcion, el cual fue construido y probado en el Instituto de Investigaciones Electricas. En toda la etapa de experimentacion se obtuvo agua pura. La capacidad maxima alcanzada de produccion de agua pura de este sistema fue de 4.3 kg por hora, mostrando un rendimiento en terminos del Coeficiente Real de Rendimiento (COP)A de 1.4. Estos resultados se consideran alentadores para la proyeccion de unidades a escala industrial que puedan ser operadas con calor geotermico y/o solar.

  16. Caloric Value of Some Forest Fuels of the Southern United States

    Science.gov (United States)

    Walter A. Hough

    1969-01-01

    The caloric value of a variety of southern forest fuels was determined in an oxygen bomb calorimeter. High heat values ranged between about 3,600 and 5,200 cal./g. for fuels as sampled and between 4,500 and 5,600 cal./g. for fuels on an ash-free basis. Additional tests of forest fuels from the Southern, Eastern, and North Central United States showed a...

  17. Caloric restriction and intermittent fasting: Two potential diets for successful brain aging

    OpenAIRE

    Martin, Bronwen; Mark P. Mattson; Maudsley, Stuart

    2006-01-01

    The vulnerability of the nervous system to advancing age is all too often manifest in neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In this review article we describe evidence suggesting that two dietary interventions, caloric restriction (CR) and intermittent fasting (IF), can prolong the health-span of the nervous system by impinging upon fundamental metabolic and cellular signaling pathways that regulate life-span. CR and IF affect energy and oxygen radical meta...

  18. Vestibular Function Tests for Vestibular Migraine: Clinical Implication of Video Head Impulse and Caloric Tests

    Science.gov (United States)

    Kang, Woo Seok; Lee, Sang Hun; Yang, Chan Joo; Ahn, Joong Ho; Chung, Jong Woo; Park, Hong Ju

    2016-01-01

    Vestibular migraine (VM) is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT), caloric test, vestibular-evoked myogenic potentials (VEMPs), and sensory organization test (SOT) at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR) was defined as no need for continued medication, partial response (PR) as improved symptoms but need for continued medication, and no response (NR) as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11%) exhibited abnormal vHIT results, 14 of 73 (19%) exhibited abnormal caloric test results, 25 of 65 (38%) exhibited abnormal SOT results, 8 of 75 (11%) exhibited abnormal cervical VEMP results, and 20 of 75 (27%) exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78%) no longer required medication (CR), while 18 (22%) still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively). Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  19. Dimensionamiento de intercambiadores de calor de coraza y tubos, con ayuda de computador

    OpenAIRE

    Gabriel Eduardo Rocha Camino; Rangel Jara, Hermes A.

    2011-01-01

    En este trabajo se plantea el problema de optimizar el diseño de un intercambiador de calor del tipo coraza y tubos, y se propone un método para resolverlo, con base en la técnica del "estudio paramétrico de la respuesta". Además, se muestra la necesidad de utilizar el computador como herramienta para Implementar dicho método, y se describe un programa escrito con tal fin.

  20. Vestibular Function Tests for Vestibular Migraine: Clinical Implication of Video Head Impulse and Caloric Tests.

    Science.gov (United States)

    Kang, Woo Seok; Lee, Sang Hun; Yang, Chan Joo; Ahn, Joong Ho; Chung, Jong Woo; Park, Hong Ju

    2016-01-01

    Vestibular migraine (VM) is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT), caloric test, vestibular-evoked myogenic potentials (VEMPs), and sensory organization test (SOT) at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR) was defined as no need for continued medication, partial response (PR) as improved symptoms but need for continued medication, and no response (NR) as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11%) exhibited abnormal vHIT results, 14 of 73 (19%) exhibited abnormal caloric test results, 25 of 65 (38%) exhibited abnormal SOT results, 8 of 75 (11%) exhibited abnormal cervical VEMP results, and 20 of 75 (27%) exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78%) no longer required medication (CR), while 18 (22%) still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively). Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  1. Vestibular function tests for vestibular migraine: clinical implication of video head impulse and caloric tests

    Directory of Open Access Journals (Sweden)

    Woo Seok Kang

    2016-09-01

    Full Text Available Vestibular migraine (VM is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT, caloric test, vestibular-evoked myogenic potentials (VEMP, and sensory organization test (SOT at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR was defined as no need for continued medication, partial response (PR as improved symptoms but need for continued medication, and no response (NR as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11% exhibited abnormal vHIT results, 14 of 73 (19% exhibited abnormal caloric test results, 25 of 65 (38% exhibited abnormal SOT results, 8 of 75 (11% exhibited abnormal cervical VEMP results, and 20 of 75 (27% exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78% no longer required medication (CR, while 18 (22% still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively. Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  2. Temas de Física para Ingeniería: Temperatura y propagación del calor

    OpenAIRE

    Beléndez Vázquez, Augusto

    1992-01-01

    Acústica, fluidos y termodinámica: "Temperatura y propagación del calor". Introducción. Descripciones macroscópica y microscópica de un sistema. Equilibrio térmico y principio cero de la termodinámica. Termómetros y escala de temperaturas del gas ideal. Dilatación térmica. Propagación del calor.

  3. Cervical vestibular evoked myogenic potentials and caloric test results in individuals with auditory neuropathy spectrum disorders.

    Science.gov (United States)

    Sujeet, Kumar Sinha; Niraj, Kumar Singh; Animesh, Barman; Rajeshwari, G; Sharanya, R

    2014-01-01

    Auditory neuropathy spectrum disorder is a type of hearing loss where outer hair cell function are normal (as evidenced by the preservation of OAEs and cochlear microphonics), whereas auditory nerve functions are abnormal (as evidenced by abnormal auditory brainstem evoked potentials beginning with wave I of the ABR) and acoustic reflexes to ipsilateral and contralateral tones are absent. It is likely that in cases with auditory neuropathy spectrum disorder not only the cochlear nerve, but also the vestibular nerves might get involved. The present study was conducted with an aim of finding out the inferior and superior vestibular nerve involvement through cervical vestibular evoked myogenic potentials and Caloric test results respectively in individuals with Auditory Neuropathy Spectrum Disorders. Total 26 participants who fulfilled the criteria of auditory neuropathy spectrum disorder participated for the study. Vestibular evoked myogenic potentials results showed absence of responses from most of the subjects also caloric responses showed bilateral hypofunctional responses in most of the participants, which is suggestive of involvement of both the inferior as well as superior vestibular nerve in individuals with auditory neuropathy spectrum disorders. Additionally there was no association between the pattern and degree of hearing loss to caloric test results and vestibular evoked myogenic potentials results findings.

  4. Peripheral ghrelin enhances sweet taste food consumption and preference, regardless of its caloric content.

    Science.gov (United States)

    Disse, Emmanuel; Bussier, Anne-Lise; Veyrat-Durebex, Christelle; Deblon, Nicolas; Pfluger, Paul T; Tschöp, Matthias H; Laville, Martine; Rohner-Jeanrenaud, Françoise

    2010-09-01

    Ghrelin is one of the most potent orexigens known to date. While the prevailing view is that ghrelin participates in the homeostatic control of feeding, the question arose as to whether consummatory responses evoked by this compound could be related to search for reward. We therefore attempted to delineate the involvement of ghrelin in the modulation of non-caloric but highly rewarding consumption. We tested the effect of intraperitoneally injected ghrelin on the acceptance and preference for a 0.3% saccharin solution using single bottle tests and free-choice preference test procedures in C57BL6/J mice, as well as in mice lacking the ghrelin receptor (GHSR1a -/-) and their wild-type (WT) littermates. In the single bottle tests, peripheral ghrelin consistently increased the consumption of saccharin, independently of availability of caloric food. In the free-choice preference test procedures, ghrelin increased the preference for saccharin in WT mice, while it did had not effect in GHSR1a -/-animals, indicating that the ghrelin receptor pathway is necessary to mediate this parameter. Peripheral ghrelin enhances intake and preference for a sweet food, regardless of whether the food has caloric content. This effect, mediated through the ghrelin receptor pathway, may serve as additional enhancers of energy intake. Copyright 2010 Elsevier Inc. All rights reserved.

  5. CALOR2012 XVth International Conference on Calorimetry in High Energy Physics

    Energy Technology Data Exchange (ETDEWEB)

    Akchurin, Nural .

    2015-05-04

    The International Conferences on Calorimetry in High Energy Physics, or the CALOR series, have always been where the calorimeter experts come together to review the state of calorimetry and bring forth new ideas every two years. The fteenth conference, CALOR2012, in Santa Fe was no exception. Although they were built roughly a decade ago, we are now witnessing the exceptional power of the LHC calorimeters and the crucial role they have been playing in the discovery of the 125 GeV Higgs-like boson. As we ruminate on the coming generation of experiments at the next (linear) collider and on the upgrades at the LHC, we are heartened by the substantial advances we made in calorimetry in the last decade. These advances will certainly help uncover new physics in the years to come, not only at colliders but also in astroparticle experiments that take advantage of natural elements such as air, water, and ice. The proceedings were published by the IOP in Journal of Physics, Vol 404 2011. The conference web site is calor2012.ttu.edu.

  6. Importance of silvopastoral systems on caloric stress reduction in tropical livestock productions

    Directory of Open Access Journals (Sweden)

    Alexander Navas Panadero

    2010-06-01

    Full Text Available Livestock systems in Colombia have been developed taking concepts and technologies from the green revolution, where gramineous monocrop is privileged over arboreal cover in grazing lands. This model has not taken into account the climatic conditions of the different tropical ecosystems, in which variables as temperature, relative humidity and evaporation can limit the animal´s productive and reproductive efficiency, besides being a risk factor for illness occurrence in the herd. Bos Taurus and Bos Indicus breeds show termoneutral ranges where its genetic potential can be express. However, out of this comfort area animals can enter in caloric stress which in consequence reduces its performance and sometimes can end up causing death. Silvopastoral systems comprise several functions; it contributes to lessen caloric stress since temperature under the tree canopy can reach between 2 and 9°C lower in comparison to open pastures. Differences in temperature reduction have been found among silvopastoral systems and species, being the tree group arrangements and the species with high density canopy, those with superior effect. Interactions among components should be analyzed in order to design systems that incorporate enough arboreal cover to achieve caloric stress reductions, but without affecting forage production in pastures. Silvopastoral systems contribute to improve animal welfare.

  7. Effects of caloric deprivation and satiety on sensitivity of the gustatory system

    Directory of Open Access Journals (Sweden)

    Zverev Yuriy P

    2004-02-01

    Full Text Available Abstract Background Sensitivity of the gustatory system could be modulated by a number of short-term and long-term factors such as body mass, gender, age, local and systemic diseases and pathological processes, excessive alcohol drinking, drug dependence, smoking, composition of oral fluid, state of oral hygiene, consumption of some foods among many others. A few studies have demonstrated the effects of hunger and caloric satiety on sensitivity of the gustatory system in obese humans and animals. The aim of the present study was to assess the effects of short-term caloric deprivation and satiety on recognition taste thresholds of healthy, non-smoking, non-drinking, non-obese young male subjects. The two-alternative forced-choice technique was used to measure taste threshold. Results Recognition thresholds for sucrose and salt were significantly lower during fasting state than after a meal (t = 2.23, P Conclusions Short-term caloric deprivation in our study model was associated with increased taste sensitivity to sweet and salty substances compared to satiated state while taste sensitivity to bitter substances was not affected by the conditions of measurements. Selective modulation of sensitivity of the gustatory system might reflect the different biological importance of salty, sweet and bitter qualities of taste.

  8. Subjective Visual Vertical during Caloric Stimulation in Healthy Subjects: Implications to Research and Neurorehabilitation

    Directory of Open Access Journals (Sweden)

    Martha Funabashi

    2015-01-01

    Full Text Available Background. The subjective visual vertical (SVV is a perception often impaired in patients with neurologic disorders and is considered a sensitive tool to detect otolithic dysfunctions. However, it remains unclear whether the semicircular canals (SCCs are also involved in the visual vertical perception. Objective. The aim of this study was to analyze the influence of horizontal SCCs on SVV by caloric stimulation in healthy subjects. Methods. SVV was performed before and during the ice-cold caloric stimulation (4°C, right ear in 30 healthy subjects. Results. The mean SVV tilts before and during the caloric stimulation were 0.31° ± 0.39 and −0.28° ± 0.40, respectively. There was no significant difference between the mean SVV tilts before and during stimulation p=0.113. Conclusion. These results suggest that horizontal SCCs do not influence SVV. Therefore, investigations and rehabilitation approaches for SVV misperceptions should be focused on otolithic and cognitive strategies.

  9. Feeding preference of adult females of ribbonfish Trichiurus lepturus through prey proximate-composition and caloric values

    Directory of Open Access Journals (Sweden)

    Vanessa Trindade Bittar

    Full Text Available In the present study we analysed the proximate-composition and caloric values of the preferred prey consumed by ribbonfish, Trichiurus lepturus L. 1758 (adult females, that are distributed in the inner continental shelf from northern Rio de Janeiro State, southeastern Brazil (~22ºS, assessing the potential of nutritional and energetic approach as a tool to understand the feeding selective pattern of this marine top carnivore. The preferred prey of this predator composed of fish co-specifics, Pellona harroweri, Chirocentrodon bleekerianus, Lycengraulis grossidens, Peprilus paru, squid Doryteuthis plei, and shrimp Xiphopenaeus kroyeri were collected from 2007 to 2010 for proximate-composition (water, protein, lipid, ash, and carbohydrate and caloric value analyses. The correspondence analysis showed that protein is the main component in the prey species (61.32% of variance explained, standing out from the other nutrients. Lipid has the highest percentage related to L. grossidens, ash to X. kroyeri and carbohydrate to D. plei. The strong correlations between protein and caloric value (positive and lipid and caloric value (negative indicated that T. lepturus is attending its energy demand through the prey protein content. This work elucidated the feeding preference of adult females of T. lepturus in relation to nutritional and caloric content of their preferred prey. The species showed food selectivity to prey that provide more energy per ingested biomass, so that the feeding events can maximize the predator's caloric gain, which is obtained by a protein-based diet.

  10. Saccharin and aspartame, compared with sucrose, induce greater weight gain in adult Wistar rats, at similar total caloric intake levels.

    Science.gov (United States)

    Feijó, Fernanda de Matos; Ballard, Cíntia Reis; Foletto, Kelly Carraro; Batista, Bruna Aparecida Melo; Neves, Alice Magagnin; Ribeiro, Maria Flávia Marques; Bertoluci, Marcello Casaccia

    2013-01-01

    It has been suggested that the use of nonnutritive sweeteners (NNSs) can lead to weight gain, but evidence regarding their real effect in body weight and satiety is still inconclusive. Using a rat model, the present study compares the effect of saccharin and aspartame to sucrose in body weight gain and in caloric intake. Twenty-nine male Wistar rats received plain yogurt sweetened with 20% sucrose, 0.3% sodium saccharin or 0.4% aspartame, in addition to chow and water ad libitum, while physical activity was restrained. Measurements of cumulative body weight gain, total caloric intake, caloric intake of chow and caloric intake of sweetened yogurt were performed weekly for 12 weeks. Results showed that addition of either saccharin or aspartame to yogurt resulted in increased weight gain compared to addition of sucrose, however total caloric intake was similar among groups. In conclusion, greater weight gain was promoted by the use of saccharin or aspartame, compared with sucrose, and this weight gain was unrelated to caloric intake. We speculate that a decrease in energy expenditure or increase in fluid retention might be involved.

  11. Economic management of vertigo/dizziness disease in a county hospital: video-head-impulse test vs. caloric irrigation.

    Science.gov (United States)

    Rambold, Holger A

    2015-10-01

    The video-head-impulse test (vHIT) is an important test for examining unilateral vestibular hypofunction. Alternatively, one can test for vestibular hypofunction with the caloric irrigation test. Various studies have shown that both tests may not always identify vestibular hypofunction; instead, the results of the tests might be contradictory. This retrospective study reproduces those finding in a much larger group of patients at a county hospital. 1063 patients were examined with the vHIT and bithermal caloric irrigation on the same day and analyzed with respect to side differences. Of those patients 13.3% had pathological vHIT and a caloric irrigation test, 4.6% a pathological vHIT only and 24.1% a pathologic caloric test only. As both tests might be necessary, we calculated the optimal sequence of the two examinations based on savings in time for the different disease groups. Especially in vestibular failure using the vHIT first and only applying the caloric irrigation in case of an unremarkable vHIT saves time and optimizes the diagnostic work up. In contrast, in Menière's disease and vestibular migraine testing caloric irrigation first might be more efficient.

  12. Composição centesimal e valor calórico de alimentos de origem animal Proximate food composition and caloric value of foods from animal origen

    Directory of Open Access Journals (Sweden)

    Elizabeth A.F.S TORRES

    2000-08-01

    Full Text Available Dados sobre composição de alimentos são importantes para inúmeras atividades, porém são escassos ou inexistentes em nosso país. O presente trabalho teve como objetivo determinar o valor calórico dos alimentos de origem animal comumente usados na dieta: carne, leite e ovos a fim de compará-los com os dados das tabelas de composição centesimal mais utilizadas por profissionais da área. Observou-se que de um modo geral, ocorrem variações entre os valores das tabelas consultadas e os analisados, sendo estes menores para ovos, seguidos de laticínios, carnes suínas, carnes bovinas e aves. Salientamos portanto, a importãncia de obtenção dados sobre a composição de alimentos condizentes com diferenças regionais do Brasil, visto que a maioria das tabelas disponíveis são compilações de dados internacionais.Proximate food composition data are very important to any professionals of food science and human nutrition area. In Brazil they are rare or do not exist. The food composition of items, of animal origin, usually consumed in the diet: meat, milk e eggs, were analyzed in order to determine their caloric value. After that they were compared with the data in the Tables of Food Composition (TFC commonly used to our professionals. It was observed that there are smaller differences in the values obtained for eggs, than milk, pork, beef, chicken. Although significant difference was not detected between determined caloric values and the ones from TFC, these report should be considered to professionals that use the TFC.

  13. Tendências das séries históricas do índice de calor no município de Santa Maria - RS

    Directory of Open Access Journals (Sweden)

    Stefanía Dalmolin da Silva

    2014-01-01

    Full Text Available Este trabalho teve como objetivo calcular e analisar as séries históricas mensais do Índice de Calor (IC para Santa Maria, RS, Brasil, no período de 1968 a 2011. As variáveis meteorológicas utilizadas neste trabalho foram pressão atmosférica, temperatura do bulbo seco e temperatura do bulbo úmido, no horário das 9h (12UTC, 15h (18UTC e 21h (00UTC. Foi realizada análise de tendência das séries históricas para o valor absoluto e a média mensais do IC através do teste de Mann-Kendall e análise de regressão linear simples para quantificar a tendência, com nível de significância de 95% (α=0,05. Para o valor máximo, no horário das 15h (18UTC, as séries históricas para os meses de janeiro e abril apresentaram acréscimo no valor do índice de calor na magnitude de 0,76°C década-1 e 0,92°C década-1, respectivamente. No horário das 21h (00 UTC, os meses de abril e novembro apresentaram aumento de 0,43°C década-1 e 0,55°C década-1, respectivamente. Porém os meses de maio e agosto apresentaram diminuição de 0,69°C década-1 e 0,31°C década-1, respectivamente.

  14. Thermal transient anemometer

    Science.gov (United States)

    Bailey, James L.; Vresk, Josip

    1989-01-01

    A thermal transient anemometer having a thermocouple probe which is utilized to measure the change in temperature over a period of time to provide a measure of fluid flow velocity. The thermocouple probe is located in the fluid flow path and pulsed to heat or cool the probe. The cooling of the heated probe or the heating of the cooled probe from the fluid flow over a period of time is measured to determine the fluid flow velocity. The probe is desired to be locally heated near the tip to increase the efficiency of devices incorporating the probe.

  15. DSN Transient Observatory

    Science.gov (United States)

    Kuiper, T. B. H.; Monroe, R. M.; White, L. A.; Garcia Miro, C.; Levin, S. M.; Majid, W. A.; Soriano, M.

    2016-11-01

    The Deep Space Network (DSN) Transient Observatory (DTO) is a signal processing facility that can monitor up to four DSN downlink bands for astronomically interesting signals. The monitoring is done commensally with reception of deep space mission telemetry. The initial signal processing is done with two CASPERa ROACH1 boards, each handling one or two baseband signals. Each ROACH1 has a 10 GBe interface with a GPU-equipped Debian Linux workstation for additional processing. The initial science programs include monitoring Mars for electrostatic discharges, radio spectral lines, searches for fast radio bursts and pulsars and SETI. The facility will be available to the scientific community through a peer review process.

  16. Transient regional osteoporosis

    Directory of Open Access Journals (Sweden)

    F. Trotta

    2011-09-01

    Full Text Available Transient osteoporosis of the hip and regional migratory osteoporosis are uncommon and probably underdiagnosed bone diseases characterized by pain and functional limitation mainly affecting weight-bearing joints of the lower limbs. These conditions are usually self-limiting and symptoms tend to abate within a few months without sequelae. Routine laboratory investigations are unremarkable. Middle aged men and women during the last months of pregnancy or in the immediate post-partum period are principally affected. Osteopenia with preservation of articular space and transitory edema of the bone marrow provided by magnetic resonance imaging are common to these two conditions, so they are also known by the term regional transitory osteoporosis. The appearance of bone marrow edema is not specific to regional transitory osteoporosis but can be observed in several diseases, i.e. trauma, reflex sympathetic dystrophy, avascular osteonecrosis, infections, tumors from which it must be differentiated. The etiology of this condition is unknown. Pathogenesis is still debated in particular the relationship with reflex sympathetic dystrophy, with which regional transitory osteoporosis is often identified. The purpose of the present review is to remark on the relationship between transient osteoporosis of the hip and regional migratory osteoporosis with particular attention to the bone marrow edema pattern and relative differential diagnosis.

  17. Transient Black Hole Binaries

    CERN Document Server

    Belloni, T M

    2016-01-01

    The last two decades have seen a great improvement in our understand- ing of the complex phenomenology observed in transient black-hole binary systems, especially thanks to the activity of the Rossi X-Ray Timing Explorer satellite, com- plemented by observations from many other X-ray observatories and ground-based radio, optical and infrared facilities. Accretion alone cannot describe accurately the intricate behavior associated with black-hole transients and it is now clear that the role played by different kinds of (often massive) outflows seen at different phases of the outburst evolution of these systems is as fundamental as the one played by the accretion process itself. The spectral-timing states originally identified in the X-rays and fundamentally based on the observed effect of accretion, have acquired new importance as they now allow to describe within a coherent picture the phenomenology observed at other wave- length, where the effects of ejection processes are most evident. With a particular focu...

  18. Characterizing Nanoscale Transient Communication.

    Science.gov (United States)

    Chen, Yifan; Anwar, Putri Santi; Huang, Limin; Asvial, Muhamad

    2016-04-01

    We consider the novel paradigm of nanoscale transient communication (NTC), where certain components of the small-scale communication link are physically transient. As such, the transmitter and the receiver may change their properties over a prescribed lifespan due to their time-varying structures. The NTC systems may find important applications in the biomedical, environmental, and military fields, where system degradability allows for benign integration into life and environment. In this paper, we analyze the NTC systems from the channel-modeling and capacity-analysis perspectives and focus on the stochastically meaningful slow transience scenario, where the coherence time of degeneration Td is much longer than the coding delay Tc. We first develop novel and parsimonious models to characterize the NTC channels, where three types of physical layers are considered: electromagnetism-based terahertz (THz) communication, diffusion-based molecular communication (DMC), and nanobots-assisted touchable communication (TouchCom). We then revisit the classical performance measure of ϵ-outage channel capacity and take a fresh look at its formulations in the NTC context. Next, we present the notion of capacity degeneration profile (CDP), which describes the reduction of channel capacity with respect to the degeneration time. Finally, we provide numerical examples to demonstrate the features of CDP. To the best of our knowledge, the current work represents a first attempt to systematically evaluate the quality of nanoscale communication systems deteriorating with time.

  19. Calculating transient rates from surveys

    CERN Document Server

    Carbone, Dario; Wijers, Ralph A M J; Rowlinson, Antonia

    2016-01-01

    We have developed a method to determine the transient surface density and transient rate for any given survey, using Monte-Carlo simulations. This method allows us to determine the transient rate as a function of both the flux and the duration of the transients in the whole flux-duration plane rather than one or a few points as currently available methods do. It is applicable to every survey strategy that is monitoring the same part of the sky, regardless the instrument or wavelength of the survey, or the target sources. We have simulated both top-hat and Fast Rise Exponential Decay light curves, highlighting how the shape of the light curve might affect the detectability of transients. Another application for this method is to estimate the number of transients of a given kind that are expected to be detected by a survey, provided that their rate is known.

  20. Calculating transient rates from surveys

    Science.gov (United States)

    Carbone, D.; van der Horst, A. J.; Wijers, R. A. M. J.; Rowlinson, A.

    2017-03-01

    We have developed a method to determine the transient surface density and transient rate for any given survey, using Monte Carlo simulations. This method allows us to determine the transient rate as a function of both the flux and the duration of the transients in the whole flux-duration plane rather than one or a few points as currently available methods do. It is applicable to every survey strategy that is monitoring the same part of the sky, regardless the instrument or wavelength of the survey, or the target sources. We have simulated both top-hat and Fast Rise Exponential Decay light curves, highlighting how the shape of the light curve might affect the detectability of transients. Another application for this method is to estimate the number of transients of a given kind that are expected to be detected by a survey, provided that their rate is known.

  1. The Zwicky Transient Facility

    Science.gov (United States)

    Kulkarni, Shrinivas R.

    2016-01-01

    The Zwicky Transient Facility (ZTF) has been designed with a singular focus: a systematic exploration of the night sky at a magnitude level well suited for spectral classification and follow up with the existing class of 4-m to 10-m class telescopes. ZTF is the successor to the Palomar Transient Factory (PTF). The discovery engine for ZTF is a 47 square degree camera (realized through 16 e2V monolithic CCDs) that fills the entire focal plane of the 48-inch Oschin telescope of the Palomar Observatory. Single 30-s epoch sensitivity is about 20.5 in g and R bands. The Infarared Processing & Analysis Center (IPAC) is the data center for ZTF. ZTF is a public-private partnership with equal contributions from a consortium of world-wide partners and an NSF MSIP grant. Forty percent of ZTF time is set aside for two major community surveys: a 3-day cadence survey of high latitudes (to mimic LSST) and a time domain survey of the entire Northern Galactic plane. We expect first light in February 2017 and begin a 3-year survey starting summer of 2017. The first year will be spent on building up deep reference images of the sky (a must for transient surveys). During the second year IPAC will deliver near archival quality photometric products within 12 hours of observations. By comparison to reference images photometric alerts will be sent out. Year 3 will see the near real-time release of image differencing products. A Community Science Advisory Committee (CSAC), chaired by S. Ridgway (NOAO), has been set up to both advise the PI and to ensure that the US community's interests are well served. Astronomers interested in getting a head start on ZTF may wish to peruse the data releases from PTF. Young people (or young at heart) may wish to attend the annual summer school on PTF/ZTF (August, Caltech campus). The Principal Investigator (PI) for the project is S. Kulkarni and the Project Scientist is Eric Bellm.For further details please consult http://www.ptf.caltech.edu/ztf

  2. The joy of transient chaos

    Energy Technology Data Exchange (ETDEWEB)

    Tél, Tamás [Institute for Theoretical Physics, Eötvös University, and MTA-ELTE Theoretical Physics Research Group, Pázmány P. s. 1/A, Budapest H-1117 (Hungary)

    2015-09-15

    We intend to show that transient chaos is a very appealing, but still not widely appreciated, subfield of nonlinear dynamics. Besides flashing its basic properties and giving a brief overview of the many applications, a few recent transient-chaos-related subjects are introduced in some detail. These include the dynamics of decision making, dispersion, and sedimentation of volcanic ash, doubly transient chaos of undriven autonomous mechanical systems, and a dynamical systems approach to energy absorption or explosion.

  3. Transient osteoporosis of pregnancy.

    Science.gov (United States)

    Maliha, George; Morgan, Jordan; Vrahas, Mark

    2012-08-01

    Transient osteoporosis of pregnancy (TOP) is a rare yet perhaps under-reported condition that has affected otherwise healthy pregnancies throughout the world. The condition presents suddenly in the third trimester of a usually uneventful pregnancy and progressively immobilizes the mother. Radiographic studies detect drastic loss of bone mass, elevated rates of turnover in the bone, and oedema in the affected portion. Weakness of the bone can lead to fractures during delivery and other complications for the mother. Then, within weeks of labour, symptoms and radiological findings resolve. Aetiology is currently unknown, although neural, vascular, haematological, endocrine, nutrient-deficiency, and other etiologies have been proposed. Several treatments have also been explored, including simple bed rest, steroids, bisphosphonates, calcitonin, induced termination of pregnancy, and surgical intervention. The orthopedist plays an essential role in monitoring the condition (and potential complications) as well as ensuring satisfactory outcomes for both the mother and newborn.

  4. Transient Detection and Classification

    CERN Document Server

    Becker, Andrew C

    2008-01-01

    I provide an incomplete inventory of the astronomical variability that will be found by next-generation time-domain astronomical surveys. These phenomena span the distance range from near-Earth satellites to the farthest Gamma Ray Bursts. The surveys that detect these transients will issue alerts to the greater astronomical community; this decision process must be extremely robust to avoid a slew of ``false'' alerts, and to maintain the community's trust in the surveys. I review the functionality required of both the surveys and the telescope networks that will be following them up, and the role of VOEvents in this process. Finally, I offer some ideas about object and event classification, which will be explored more thoroughly by other articles in these proceedings.

  5. Stability of Ignition Transients

    Directory of Open Access Journals (Sweden)

    V.E. Zarko

    1991-07-01

    Full Text Available The problem of ignition stability arises in the case of the action of intense external heat stimuli when, resulting from the cut-off of solid substance heating, momentary ignition is followed by extinction. Physical pattern of solid propellant ignition is considered and ignition criteria available in the literature are discussed. It is shown that the above mentioned problem amounts to transient burning at a given arbitrary temperature distribution in the condensed phase. A brief survey of published data on experimental and theoretical studies on ignition stability is offered. The comparison between theory and experiment is shown to prove qualitatively the efficiency of the phenomenological approach in the theory. However, the methods of mathematical simulation as well as those of experimental studying of ignition phenomenon, especially at high fluxes, need to be improved.

  6. Effects of emodin on treating murine nonalcoholic fatty liver induced by high caloric laboratory chaw

    Institute of Scientific and Technical Information of China (English)

    Hui Dong; Fu-Er Lu; Zhi-Qiang Gao; Li-Jun Xu; Kai-Fu Wang; Xin Zou

    2005-01-01

    AIM: To investigate the effects of emodin on the treatment of non-alcoholic fatty liver in rats induced by high caloric laboratory chaw.METHODS: Non-alcoholic fatty liver model was successfully established by feeding with high caloric laboratory chaw for 12 wk. Then the model rats were randomly divided into 3 groups, namely model control group, emodin group and dietary treatment group. The rats in emodin group in othergroups were given distilled water of the same volume. The rats in model control group were fed with high caloric laboratory chaw while animals in other groups were fed with normal diet. Four weeks later, liver index (liver/body weight ratio), serum activities of liver-associated enzymes, blood lipid, fasting blood glucose, fasting plasma insulin, HOMA insulin resistance index (HOMA-IR), hepatic triglyceride content and histology features of all groups were assayed. The expression of hepatic peroxisomal proliferator activated receptor (PPAR) gamma was determined by RT-PCR.RESULTS: The body weight, liver index, serum activities of alanine aminotransferase (ALT), blood lipid, hepatic triglyceride content of model control group were significantly elevated, with moderate to severe hepatocyte steatosis.The expression of hepatic PPAR gamma mRNA was obviously reduced in model control group. Compared with model control group, the body weight, liver index, serum activities of ALT, blood lipids and hepatic triglyceride of emodin group significantly decreased and hepatic histology display was also greatly improved. Meanwhile, the expression of hepatic PPAR gamma mRNA was elevated.However, high serum activities of ALT and hyperlipidemia were persisted in dietary treatment group although liver index was decreased and liver histology was somewhat improved.CONCLUSION: It is suggested that emodin might be effective in the treatment of non-alcoholic fatty liver in rats. Its therapeutic mechanism could be associated with increasing the expression of hepatic PPAR gamma mRNA.

  7. [Caloric value and ash content of dominant plants in plantation communities in Heshan of Guangdong, China].

    Science.gov (United States)

    Zeng, Xiao-ping; Cai, Xi-an; Zhao, Ping; Rao, Xing-quan

    2009-03-01

    Different parts of twenty dominant plant species in five plantation communities on the subtropical hilly lands in Heshan of Gunagdong as well as the litters from three of the five plantation communities were sampled, and their gross caloric value (GCV) and ash content were measured by using a PARR-1281 oxygen bomb calorimeter and a muffle furnace. Based on the measurements, the ash-free caloric value (AFCV) of the samples was calculated, and the characteristics of caloric value and ash content of the samples, according to plant part, individual, and plant growth form, were analyzed. The results showed that the GCV and AFCV of leaf, branch, stem wood, stem bark, and root were in the range of 10.7-22.17 kJ x g(-1) and 13.89-23.04 kJ x g(-1), respectively. The GCV and AFCV of leaf were significantly higher than those of other parts (P shrub layer (19.46 kJ x g(-1) > herb layer (18.77 kJ x g(-1)), with indigenous coniferous tree (19.86 kJ x g(-1)) > indigenous broad-leaved tree (19.55 kJ x g(-1)) > exotic eucalyptus (19.18 kJ x g(-1)), while the mean ash content was just the opposite. In Acacia mangium, coniferous, and Schima plantation communities, the GCV and AFCV of litters were higher than those of various plant parts (P mangium and coniferous plantations had higher mean GCV and AFCV than the litters and fresh leaves of tree layer, while the fresh leaves of tree layer in Schima plantation showed higher mean GCV and AFCV.

  8. Caloric beverages were major sources of energy among children and adults in Mexico, 1999-2012.

    Science.gov (United States)

    Stern, Dalia; Piernas, Carmen; Barquera, Simon; Rivera, Juan A; Popkin, Barry M

    2014-06-01

    Mexico, with 1 of the highest obesity prevalences in the world, instituted a 10% excise tax for any sugar-sweetened beverage (SSB) starting on 1 January 2014. Understanding the recent patterns and trends in beverage intake and sales in Mexico provides both background and baseline data for the importance of SSBs and other beverages in the Mexican diet. We analyzed a single 24-h dietary recall from 2 nationally representative surveys: the Mexican Nutrition Survey 1999 (n = 6049) and the National Health and Nutrition Survey 2012 (n = 10,343). To describe trends and patterns in beverages, we calculated the volume and energy intake per capita and per consumer and the proportion of consumers of each beverage group in each survey. A commercial sales dataset was used to describe beverage sales trends from 1999 to 2012. From 1999 to 2012, total daily energy from beverages increased among children aged 5-11 y (+45.3 kcal), females aged 12-19 y (+57.3 kcal), and adult females aged 20-49 y (+96.4 kcal) (P fat milk were the top 3 major contributors to total daily energy intake per capita in all children aged 1-19 y. Caloric soda, caloric coffee/tea, and agua fresca were the top 3 major energy contributors in adults aged ≥20 y. From 1999 to 2012, sales of soda, fruit-flavored drinks, and flavored waters increased. In conclusion, consumption of several beverages with added sugars increased among children and adult females in Mexico. Because caloric soda is currently 1 of the top beverages consumed, a 10% tax on SSBs might help to significantly reduce added sugars intake in Mexico. © 2014 American Society for Nutrition.

  9. Lost in processing? Perceived healthfulness, taste and caloric content of whole and processed organic food.

    Science.gov (United States)

    Prada, Marília; Garrido, Margarida V; Rodrigues, David

    2017-03-23

    The "organic" claim explicitly informs consumers about the food production method. Yet, based on this claim, people often infer unrelated food attributes. The current research examined whether the perceived advantage of organic over conventional food generalizes across different organic food types. Compared to whole organic foods, processed organic foods are less available, familiar and prototypical of the organic food category. In two studies (combined N = 258) we investigated how both organic foods types were perceived in healthfulness, taste and caloric content when compared to their conventional alternatives. Participants evaluated images of both whole (e.g., lettuce) and processed organic food exemplars (e.g., pizza), and reported general evaluations of these food types. The association of these evaluations with individual difference variables - self-reported knowledge and consumption of organic food, and environmental concerns - was also examined. Results showed that organically produced whole foods were perceived as more healthful, tastier and less caloric than those produced conventionally, thus replicating the well-established halo effect of the organic claim in food evaluation. The organic advantage was more pronounced among individuals who reported being more knowledgeable about organic food, consumed it more frequently, and were more environmentally concerned. The advantage of the organic claim for processed foods was less clear. Overall, processed organic (vs. conventional) foods were perceived as tastier, more healthful (Study 1) or equally healthful (Study 2), but also as more caloric. We argue that the features of processed food may modulate the impact of the organic claim, and outline possible research directions to test this assumption. Uncovering the specific conditions in which food claims bias consumer's perceptions and behavior may have important implications for marketing, health and public-policy related fields.

  10. Olas de calor e influencia urbana en Madrid y su área metropolitana

    Directory of Open Access Journals (Sweden)

    Fernández García, F.

    2008-12-01

    Full Text Available The frequency and duration of the warmest temperature episodes, a common phenomenon under the continental Mediterranean conditions of the Spanish Southern Meseta, has increased in the Madrid area since the 80´s, although their magnitude remains unchanged. The effect of the urban environment on those extreme events has exacerbated the heat load due to the persistence of the high temperatures along the night time hours. Nevertheless, the diversity of the urban morphology introduces a spatial variability on the strength of this nocturnal heat load, aggravating it in the densely urbanized areas and mitigating it in the vicinities of the green areas.

    La frecuencia y duración de los episodios cálidos extremos, un fenómeno habitual en el clima mediterráneo continental de la Meseta Meridional, ha aumentado en el área de Madrid desde los años noventa, aunque su magnitud permanece constante. En el interior de la aglomeración urbana, el efecto general de la ciudad sobre estos eventos climáticos extremos ha supuesto una exacerbación del calor, no tanto por un aumento de la temperatura máxima, como por una persistencia del calor en las horas nocturnas. No obstante, la diversidad de la morfología urbana introduce variaciones espaciales en la intensidad de este calor nocturno, agravando sus efectos en las áreas densamente urbanizadas y mitigándolos en las proximidades de las áreas verdes.

  11. Obesity, abdominal obesity, physical activity, and caloric intake in US adults: 1988 to 2010.

    Science.gov (United States)

    Ladabaum, Uri; Mannalithara, Ajitha; Myer, Parvathi A; Singh, Gurkirpal

    2014-08-01

    Obesity and abdominal obesity are associated independently with morbidity and mortality. Physical activity attenuates these risks. We examined trends in obesity, abdominal obesity, physical activity, and caloric intake in US adults from 1988 to 2010. Univariate and multivariate analyses were performed using National Health and Nutrition Examination Survey data. Average body mass index (BMI) increased by 0.37% (95% confidence interval [CI], 0.30-0.44) per year in both women and men. Average waist circumference increased by 0.37% (95% CI, 0.30-0.43) and 0.27% (95% CI, 0.22-0.32) per year in women and men, respectively. The prevalence of obesity and abdominal obesity increased substantially, as did the prevalence of abdominal obesity among overweight adults. Younger women experienced the greatest increases. The proportion of adults who reported no leisure-time physical activity increased from 19.1% (95% CI, 17.3-21.0) to 51.7% (95% CI, 48.9-54.5) in women, and from 11.4% (95% CI, 10.0-12.8) to 43.5% (95% CI, 40.7-46.3) in men. Average daily caloric intake did not change significantly. BMI and waist circumference trends were associated with physical activity level but not caloric intake. The associated changes in adjusted BMIs were 8.3% (95% CI, 6.9-9.6) higher among women and 1.7% (95% CI, 0.68-2.8) higher among men with no leisure-time physical activity compared with those with an ideal level of leisure-time physical activity. Our analyses highlight important dimensions of the public health problem of obesity, including trends in younger women and in abdominal obesity, and lend support to the emphasis placed on physical activity by the Institute of Medicine. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Caloric restriction in C57BL/6J mice mimics therapeutic fasting in humans

    Directory of Open Access Journals (Sweden)

    Denny Christine A

    2006-05-01

    Full Text Available Abstract Background Caloric restriction (CR has long been recognized as a dietary therapy that improves health and increases longevity. Little is known about the persistent effects of CR on plasma biomarkers (glucose, ketone bodies, and lipids following re-feeding in mice. It is also unclear how these biomarker changes in calorically restricted mice relate to those observed previously in calorically restricted humans. Results Three groups of individually housed adult female C57BL/6J (B6 mice (n = 4/group were fed a standard rodent chow diet either: (1 unrestricted (UR; (2 restricted for three weeks to reduce body weight by approximately 15–20% (R; or (3 restricted for three weeks and then re-fed unrestricted (ad libitum for an additional three weeks (R-RF. Body weight and food intake were measured throughout the study, while plasma lipids and levels of glucose and ketone bodies (β-hydroxybutyrate were measured at the termination of the study. Plasma glucose, phosphatidylcholine, cholesterol, and triglycerides were significantly lower in the R mice than in the UR mice. In contrast, plasma fatty acids and β-hydroxybutyrate were significantly higher in the R mice than in the UR mice. CR had no effect on plasma phosphatidylinositol levels. While body weight and plasma lipids of the R-RF mice returned to unrestricted levels upon re-feeding, food intake and glucose levels remained significantly lower than those prior to the initiation of CR. Conclusion CR establishes a new homeostatic state in B6 mice that persists for at least three weeks following ad libitum re-feeding. Moreover, the plasma biomarker changes observed in B6 mice during CR mimic those reported in humans on very low calorie diets or during therapeutic fasting.

  13. Transient heliosheath modulation

    Science.gov (United States)

    Quenby, J. J.; Webber, W. R.

    2015-10-01

    Voyager 1 has explored the solar wind-interstellar medium interaction region between the terminal shock and heliopause, following the intensity distribution of Galactic cosmic ray protons above 200 MeV energy. Before this component reached the expected galactic flux level at 121.7 au from the Sun, four episodes of rapid intensity change occurred with a behaviour similar to that found in Forbush Decreases in the inner Solar system, rather than that expected from a mechanism related to models for the long-term modulation found closer to the Sun. Because the mean solar wind flow is both expected and observed to be perpendicular to the radial direction close to the heliopause, an explanation is suggested in terms of transient radial flows related to possible heliopause boundary flapping. It is necessary that the radial flows are of the order either of the sound speed found for conditions downstream of the terminal shock or of the fluctuations found near the boundary by the Voyager 1 Low Energy Charged Particle detector and that the relevant cosmic ray diffusion perpendicular to the mean field is controlled by `slab' fluctuations accounting for about 20 per cent of the total power in the field variance. However, additional radial drift motion related to possible north to south gradients in the magnetic field may allow the inclusion of some diffusion according to the predictions of a theory based upon the presence of 2D turbulence. The required field gradients may arise due to field variation in the field carried by solar plasma flow deflected away from the solar equatorial plane. Modulation amounting to a total 30 per cent drop in galactic intensity requires explanation by a combination of transient effects.

  14. Identificación de incrustaciones en ciclones recuperadores de calor de hornos DOPOL

    Directory of Open Access Journals (Sweden)

    Triviño Vázquez, Fernando

    1979-12-01

    Full Text Available Not avaible

    En un ciclón recuperador de calor, situado a la entrada del horno de clinquerización tipo DOPOL, se producían unas incrustaciones sedimentarias que terminaban produciendo la obstrucción del ciclón. Simultáneamente aparecían dificultades de marcha durante el crecimiento, por sedimentación- fusión, de dichas incrustaciones. Finalmente era necesaria la parada del horno para la limpieza del ciclón.

  15. Rapid relief of thalamic pain syndrome induced by vestibular caloric stimulation.

    Science.gov (United States)

    Ramachandran, Vilayanur S; McGeoch, Paul D; Williams, Lisa; Arcilla, Gerard

    2007-06-01

    Central post-stroke pain syndrome develops in a minority of patients following a stroke. The most usual causative lesion involves the lateral thalamus. The classic presentation is of severe, unrelenting pain that involves the entire contralateral half of the body. It is largely refractory to current treatments. We found that in two patients with this condition their pain was substantially improved by vestibular caloric stimulation, whereas placebo procedures had no effect. We proposed that this is because vestibular stimulation activates the posterior insula, which in turn inhibits the generation of pain in the anterior cingulate.

  16. Tolerancia al calor y humedad atmosférica de diferentes grupos raciales de ganado bovino

    OpenAIRE

    2011-01-01

    Objetivo. Comparar algunas respuestas fisiológicas al calor y humedad atmosférica entre bovinos Chinampos (Bos taurus; Ch), ½ Charolais ½ Brahman (CB), Holstein (H) y Jersey (J). Materiales y métodos. Se realizó un estudio en La Paz, México. Se utilizaron 12 vacas H, 10 J, 15 Ch y 8 CB. Durante el verano se midieron cada semana (a las 0600 y 1600 horas) la frecuencia respiratoria (FR) y temperatura rectal (TR). Se registraron las variables climáticas para calcular el índice de temperatura-hum...

  17. Normal physical activity obliterates the deleterious effects of high-caloric intake

    DEFF Research Database (Denmark)

    Krogh-Madsen, Rikke; Pedersen, Maria; Solomon, Thomas

    2013-01-01

    magnetic resonance imaging (MRI)- scans, continuous glucose monitoring (CGM), and oral glucose tolerance tests (OGTT) with stable isotopes were performed before and after the intervention. Both study groups gained the same amount of body weight. However, the inactive group accumulated significantly more....... Therefore, healthy individuals on a high caloric intake were randomized to either 10,000 or 1,500 steps per day for 14 days. Step-number, total energy expenditure, dietary records, neuropsychological tests, maximal oxygen uptake (VO2max), whole body dual-energy X-ray absorptiometry (DXA)- and abdominal...

  18. Targeting energy metabolism in brain cancer with calorically restricted ketogenic diets.

    Science.gov (United States)

    Seyfried, Thomas N; Kiebish, Michael; Mukherjee, Purna; Marsh, Jeremy

    2008-11-01

    Information is presented on the calorically restricted ketogenic diet (CRKD) as an alternative therapy for brain cancer. In contrast to normal neurons and glia, which evolved to metabolize ketone bodies as an alternative fuel to glucose under energy-restricted conditions, brain tumor cells are largely glycolytic due to mitochondrial defects and have a reduced ability to metabolize ketone bodies. The CRKD is effective in managing brain tumor growth in animal models and in patients, and appears to act through antiangiogenic, anti-inflammatory, and proapoptotic mechanisms.

  19. Evaluation of a direct contact heat exchanger; Evaluacion de un intercambiador de calor de contacto directo

    Energy Technology Data Exchange (ETDEWEB)

    Siqueiros, J.; Bonilla, O. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    In this paper the application areas of the direct contact heat exchangers is discussed, as well as its main characteristics. A description is made of the experimental equipment designed and built at pilot scale including the instrumentation employed. The methodology employed as well as the analysis and the discussion of the results are also presented. [Espanol] Se mencionan las areas de aplicacion de los intercambiadores de calor de contacto directo, asi como sus caracteristicas principales. Se describe el equipo experimental a nivel piloto disenado y construido incluyendo la instrumentacion utilizada. Se presenta la metodologia empleada asi como el analisis y discusion de los resultados.

  20. Tecnologías emergentes para la conservación de alimentos sin calor

    OpenAIRE

    Fernández Molina, Juan José; Gustavo V. Barbosa-Cánovas; Swanson, Barry G.

    2001-01-01

    Not available

    Se han investigado los principios básicos de tres tecnologías emergentes para pasteurizar y esterilizar alimentos sin empleo del calor Mediante numerosos estudios se ha comprobado la efectividad de los campos eléctricos pulsantes de alta intensidad (CEPAI), los pulsos de luz (PL) y los campos magnéticos oscilantes (CMO) en la destrucción de microorganismos y enzimas de sistemas alimentarios. En la inactivación microbiana por CEPA!, el blanco principal es la me...

  1. The minimal caloric test asymmetric response in vertigo-free migraine patients

    Directory of Open Access Journals (Sweden)

    Eliana Teixeira Maranhão

    2016-02-01

    Full Text Available ABSTRACT Vertigo symptoms and subclinical vestibular dysfunctions may occur in migraine. The Minimal Caloric Test (MCT, an easy-to-perform, convenient and yet informative procedure was used to test the vestibular function in 30 vertigo-free migraine patients outside attacks and 30 paired controls. Although not statistically significant, a right-to-left nystagmus duration asymmetry greater than 25% was present in both groups. This difference was greater in the patients group, suggesting the presence of subclinical vestibular imbalance in migraine.

  2. Transferencia molecular de calor, masa y/o cantidad de movimiento

    OpenAIRE

    Betancourt Grajales, Ramiro

    2008-01-01

    Este texto fue diseñado para proveer un tratamiento integrado de las tres áreas del transporte: impulso, calor y masa. Las similitudes entre las leyes de flujo permiten aplicar directamente analogías en el cálculo del transporte haciendo una economía en el esfuerzo docente–discente acorde con las pedagogías intensivas. Muchas de las ecuaciones básicas son matemáticamente idénticas cuando se expresan en términos de las variables y densidades de flujo generalizadas. El texto comienza con tra...

  3. Transferencia molecular de calor, masa y/o cantidad de movimiento

    OpenAIRE

    Betancourt Grajales, Ramiro

    2008-01-01

    Este texto fue diseñado para proveer un tratamiento integrado de las tres áreas del transporte: impulso, calor y masa. Las similitudes entre las leyes de flujo permiten aplicar directamente analogías en el cálculo del transporte haciendo una economía en el esfuerzo docente–discente acorde con las pedagogías intensivas. Muchas de las ecuaciones básicas son matemáticamente idénticas cuando se expresan en términos de las variables y densidades de flujo generalizadas. El texto comienza con tra...

  4. Análisis de la transferencia de calor entre un lecho fluidizado y superficies sumergidas

    OpenAIRE

    Mazza, Germán Delfor

    1993-01-01

    Durante los últimos años se han realizado numerosos esfuerzos en la investigación de los fenómenos involucrados en la transferencia de calor entre un lecho fluidizado y una superficie sumergida. Sin embargo, tanto desde el punto de vista experimental como en la formulación de expresiones predictivas, los resultados no pueden considerarse convergentes, hallándose una gran dispersión de información en la bibliografía específica. Como se desarrollará en detalle en los sucesivos capítulos de esta...

  5. On entropy change measurements around first order phase transitions in caloric materials

    Science.gov (United States)

    Caron, Luana; Doan, Nguyen Ba; Ranno, Laurent

    2017-02-01

    In this work we discuss the measurement protocols for indirect determination of the isothermal entropy change associated with first order phase transitions in caloric materials. The magneto-structural phase transitions giving rise to giant magnetocaloric effects in Cu-doped MnAs and FeRh are used as case studies to exemplify how badly designed protocols may affect isothermal measurements and lead to incorrect entropy change estimations. Isothermal measurement protocols which allow correct assessment of the entropy change around first order phase transitions in both direct and inverse cases are presented.

  6. Vertigo and cerebral hemoglobin changes during unilateral caloric stimulation: a near-infrared spectroscopy study.

    Science.gov (United States)

    Iida, Masahiro; Haida, Munetaka; Igarashi, Makoto

    2009-05-01

    The aim of the present study using near-infrared spectroscopy (NIRS) is to evaluate the correlation of cerebral (parieto-temporal lobe) hemoglobin changes and vertiginous sensation during unilateral caloric stimulation. During the hot water (44 degrees C) stimulus, cerebral hemoglobin was increased bilaterally, but it was dominant ipsilaterally. During the unilateral cold water (30 degrees C) stimulus, cerebral hemoglobin was decreased on both sides, especially on the ipsilateral side. Vertigious sensation was strong in cases with marked left-right difference of cerebral hemoglobin changes. The usefulness of NIRS to investigate the relationship between peripheral vestibular organ and vestibular cortex was verified.

  7. Relationship of Mediterranean diet and caloric intake to phenoconversion in Huntington disease.

    Science.gov (United States)

    Marder, Karen; Gu, Yian; Eberly, Shirley; Tanner, Caroline M; Scarmeas, Nikolaos; Oakes, David; Shoulson, Ira

    2013-11-01

    Adherence to Mediterranean-type diet (MeDi) may delay onset of Alzheimer and Parkinson diseases. Whether adherence to MeDi affects time to phenoconversion in Huntington disease (HD), a highly penetrant, single-gene disorder, is unknown. To determine if MeDi modifies the time to clinical onset of HD (phenoconversion) in premanifest carriers participating in Prospective Huntington at Risk Observational Study (PHAROS), and to examine the effects of body mass index and caloric intake on time to phenoconversion. A prospective cohort study of 41 Huntington study group sites in the United States and Canada involving 1001 participants enrolled in PHAROS between July 1999 and January 2004 who were followed up every 9 months until 2010. A total of 211 participants aged 26 to 57 years had an expanded CAG repeat length (≥ 37). A semiquantitative food frequency questionnaire was administered 33 months after baseline. We calculated daily gram intake for dairy, meat, fruit, vegetables, legumes, cereals, fish, monounsaturated and saturated fatty acids, and alcohol and constructed MeDi scores (0-9); higher scores indicate higher adherence. Demographics, medical history, body mass index, and Unified Huntington's Disease Rating Scale (UHDRS) score were collected. Cox proportional hazards regression models to determine the association of MeDi and phenoconversion. RESULTS Age, sex, caloric intake, education status, and UHDRS motor scores did not differ among MeDi tertiles (0-3, 4-5, and 6-9). The highest body mass index was associated with the lowest adherence to MeDi. Thirty-one participants phenoconverted. In a model adjusted for age, CAG repeat length, and caloric intake, MeDi was not associated with phenoconversion (P for trend = 0.14 for tertile of MeDi, and P = .22 for continuous MeDi). When individual components of MeDi were analyzed, higher dairy consumption (hazard ratio, 2.36; 95% CI, 1.0-5.57; P = .05) and higher caloric intake (P = .04) were associated with risk of

  8. Dimensionamiento de intercambiadores de calor de coraza y tubos, con ayuda de computador

    Directory of Open Access Journals (Sweden)

    Gabriel Eduardo Rocha Camino

    2011-02-01

    Full Text Available En este trabajo se plantea el problema de optimizar el diseño de un intercambiador de calor del tipo coraza y tubos, y se propone un método para resolverlo, con base en la técnica del "estudio paramétrico de la respuesta". Además, se muestra la necesidad de utilizar el computador como herramienta para Implementar dicho método, y se describe un programa escrito con tal fin.

  9. Effect of chronic caloric restriction on physiological variables related to energy metabolism in the male Fischer 344 rat.

    Science.gov (United States)

    Duffy, P H; Feuers, R J; Leakey, J A; Nakamura, K; Turturro, A; Hart, R W

    1989-05-01

    In the present study, a number of physiological and behavioral measures that are related to metabolism were continuously monitored in 19-month-old male Fischer 344 rats that were fed ad libitum or fed a caloric restricted diet. Caloric restricted rats ate fewer meals but consumed more food during each meal and spent more time eating per meal than did rats fed ad libitum. Therefore, the timing and duration of meals as well as the total number of calories consumed may be associated with life extension. Average body temperature per day was significantly lower in restricted rats but body temperature range per day and motor activity were higher in restricted rats. Dramatic changes in respiratory quotient, indicating rapid changes in metabolic pathway and lower temperature, occurred in caloric restricted rats when carbohydrate reserves were depleted. Lower body temperature and metabolism during this time interval may result in less DNA damage, thereby increasing the survival potential of restricted rats. Nighttime feeding was found to synchronize physiological performance between ad libitum and caloric restricted rats better than daytime feeding, thereby allowing investigators to distinguish the effects of caloric restriction from those related solely to the time-of-day of feeding.

  10. Caloric restriction restores the chronological life span of the Goa1 null mutant of Candida albicans in spite of high cell levels of ROS.

    Science.gov (United States)

    Chen, Hui; Calderone, Richard; Sun, Nuo; Wang, Yun; Li, Dongmei

    2012-12-01

    The Candida albicans Goa1p is required for mitochondrial functions. In a strain lacking GOA1 (GOA31), respiration, mitochondrial membrane potential, complex I (CI) activity of the electron transport chain, and ATP synthesis are significantly decreased. A shortened chronological life span (CLS) of GOA31 occurs in 2% glucose that is associated with an increase in cell reactive oxidant species (ROS) and apoptosis. We now show that caloric restriction (CR) in media containing 0.5% glucose instead of 2% glucose-SC extends the CLS to the level of parental and gene-reconstituted strains. Paradoxically, ROS levels in GOA31 far exceed those of control strains in 0.5% glucose and, as a consequence, increased lipid peroxidation occurs even though CLS is restored. Microarray analysis was used to characterize transcriptional changes during CR in GOA31. We found that CR shifts cells of all strains to a non-glucose carbon metabolism (β-oxidation). Our model of ROS formation in GOA31 follows the paradigm that the generation of oxygen radicals from β-oxidation of cell lipids via FADH(2) (CII) and NADH (CI) creates an unfavorable cellular FADH(2)/NADH ratio that causes a transient overload in CII activity resulting in excess free cell radicals. In GOA31 the CI and peroxisomal dysfunctions increase the levels of ROS compared to control strains. Recovery from high levels of ROS may be associated with an increase in iron and sugar transporters, as well as an anti-stress response that includes the SOD1 and GPX1. Thus, CR creates a favorable growth environment, but cells of GOA31 must overcome a high but transient ROS production.

  11. Transient Go: A Mobile App for Transient Astronomy Outreach

    Science.gov (United States)

    Crichton, D.; Mahabal, A.; Djorgovski, S. G.; Drake, A.; Early, J.; Ivezic, Z.; Jacoby, S.; Kanbur, S.

    2016-12-01

    Augmented Reality (AR) is set to revolutionize human interaction with the real world as demonstrated by the phenomenal success of `Pokemon Go'. That very technology can be used to rekindle the interest in science at the school level. We are in the process of developing a prototype app based on sky maps that will use AR to introduce different classes of astronomical transients to students as they are discovered i.e. in real-time. This will involve transient streams from surveys such as the Catalina Real-time Transient Survey (CRTS) today and the Large Synoptic Survey Telescope (LSST) in the near future. The transient streams will be combined with archival and latest image cut-outs and other auxiliary data as well as historical and statistical perspectives on each of the transient types being served. Such an app could easily be adapted to work with various NASA missions and NSF projects to enrich the student experience.

  12. Caloric stimulation

    Science.gov (United States)

    ... back and forth during nystagmus. You may have vertigo , and sometimes, you can also have nausea. This ... used to find the cause of: Dizziness or vertigo Hearing loss that may be due to certain ...

  13. Slower heart rate and oxygen consumption kinetic responses in the on- and off-transient during a discontinuous incremental exercise: effects of aging Resposta lentificada da cinética da frequência cardíaca e do consumo de oxigênio na transição on e off durante o teste de exercício descontínuo incremental: efeito do envelhecimento

    Directory of Open Access Journals (Sweden)

    Rodrigo P Simões

    2013-02-01

    Full Text Available BACKGROUND: The analysis of the kinetic responses of heart rate (HR and oxygen consumption (VO2 are an important tool for the evaluation of exercise performance and health status. OBJECTIVES: The purpose of this study was to investigate the effects of aging on the HR and VO2 kinetics during the rest-exercise transition (on-transient and the exercise-recovery transition (off-transient, in addition to investigating the influence of exercise intensity (mild and moderate on these variables. METHOD: A total of 14 young (23±3 years and 14 elderly (70±4 years healthy men performed an incremental exercise testing (ramp protocol on a cycle-ergometer to determine the maximal power (MP. Discontinuous exercise testing was initiated at 10% of the MP with subsequent increases of 10% until exhaustion. The measurement of HR, ventilatory and metabolic variables and blood lactate were obtained at rest and during the discontinuous exercise. RESULTS: The lactate threshold was determined in each subject and was similar between the groups (30±7% of MP in the young group and 29±5% of MP in the elderly group, p>0.05. The HR and VO2 kinetics (on- and off-transient were slower in the elderly group compared to the young group (pCONTEXTUALIZAÇÃO: A análise da resposta cinética da frequência cardíaca (FC e do consumo de oxigênio (VO2 é uma importante ferramenta para avaliar a performance ao exercício e a condição de saúde. OBJETIVOS: Investigar o efeito do envelhecimento na resposta cinética da FC e do VO2 durante as transições repouso-exercício (fase-on e exercício-recuperação (fase-off, além de verificar a influência da intensidade do exercício (leve e moderada sobre os parâmetros cinéticos dessas variáveis. MÉTODO: Catorze homens jovens (23±3 anos e 14 homens idosos (70±4 anos aparentemente saudáveis realizaram um teste de esforço incremental tipo rampa em cicloergômetro para determinar a potência máxima (PM e um teste de exerc

  14. Slower heart rate and oxygen consumption kinetic responses in the on- and off-transient during a discontinuous incremental exercise: effects of aging Resposta lentificada da cinética da frequência cardíaca e do consumo de oxigênio na transição on e off durante o teste de exercício descontínuo incremental: efeito do envelhecimento

    Directory of Open Access Journals (Sweden)

    Rodrigo P Simões

    2012-01-01

    Full Text Available BACKGROUND: The analysis of the kinetic responses of heart rate (HR and oxygen consumption (VO2 are an important tool for the evaluation of exercise performance and health status. OBJECTIVES: The purpose of this study was to investigate the effects of aging on the HR and VO2 kinetics during the rest-exercise transition (on-transient and the exercise-recovery transition (off-transient, in addition to investigating the influence of exercise intensity (mild and moderate on these variables. METHOD: A total of 14 young (23±3 years and 14 elderly (70±4 years healthy men performed an incremental exercise testing (ramp protocol on a cycle-ergometer to determine the maximal power (MP. Discontinuous exercise testing was initiated at 10% of the MP with subsequent increases of 10% until exhaustion. The measurement of HR, ventilatory and metabolic variables and blood lactate were obtained at rest and during the discontinuous exercise. RESULTS: The lactate threshold was determined in each subject and was similar between the groups (30±7% of MP in the young group and 29±5% of MP in the elderly group, p>0.05. The HR and VO2 kinetics (on- and off-transient were slower in the elderly group compared to the young group (pCONTEXTUALIZAÇÃO: A análise da resposta cinética da frequência cardíaca (FC e do consumo de oxigênio (VO2 é uma importante ferramenta para avaliar a performance ao exercício e a condição de saúde. OBJETIVOS: Investigar o efeito do envelhecimento na resposta cinética da FC e do VO2 durante as transições repouso-exercício (fase-on e exercício-recuperação (fase-off, além de verificar a influência da intensidade do exercício (leve e moderada sobre os parâmetros cinéticos dessas variáveis. MÉTODO: Catorze homens jovens (23±3 anos e 14 homens idosos (70±4 anos aparentemente saudáveis realizaram um teste de esforço incremental tipo rampa em cicloergômetro para determinar a potência máxima (PM e um teste de exerc

  15. The MWA Transients Survey (MWATS).

    Science.gov (United States)

    Bell, M.; Murphy, T.; Kaplan, D. L.; Croft, S. D.; Hancock, P.; Rowlinson, A.; Wayth, R.; Gaensler, B.; Hurley-Walker, N.; Offringa, A.; Loi, C.; Bannister, K.; Trott, C.; Marquart, J.

    2017-01-01

    We propose the continuation of the MWA transients survey to search for and monitor low frequency transient and variable radio sources in the southern sky. This proposal is aimed at commensally utilising data from the GLEAM-X (G0008) project in semester 2017-A. The aim of this commensal data acquisition is to commission long baseline observations for transient science. In particular this will involve studying the impact of the ionosphere on calibration and imaging, and developing the techniques needed to produce science quality data products. The proposed drift scans with LST locking (see G0008 proposal) are particularly exciting as we can test image subtraction for transient and variable identification. This survey is targeted at studying objects such as AGN (intrinsic and extrinsic variability), long duration synchrotron emitters, pulsars and transients of unknown origin. The maps generated from this survey will be analysed with the Variables and Slow Transients (VAST) detection pipeline. The motivation for this survey is as follows: (i) To obtain temporal data on an extremely large and robust sample of low frequency sources to explore and quantify both intrinsic and extrinsic variability; (ii) To search and find new classes of low frequency radio transients that previously remained undetected and obscured from multi-wavelength discovery; (iii) To place rigorous statistics on the occurrence of both transients and variables prior to the Australian SKA era.

  16. Síntesis rigurosa de redes de intercambiadores de calor usando un método híbrido

    OpenAIRE

    J. M. García Hernández; J. M. Ponce Ortega; M. Serna González

    2007-01-01

    En este artículo se presenta un método híbrido para la síntesis de redes de intercambio de calor que incluye el diseño detallado de los intercambiadores de calor. Para realizar esta tarea se combinan las reglas heurísticas del análisis de pliegue con una técnica de programación matemática, junto con un algoritmo de optimización de intercambiadores de calor de coraza y tubos basado en el método riguroso Bell-Delaware. De esta manera, las caídas de presión de las corrientes son tratadas como va...

  17. Caloric restriction promotes cell survival in a mouse model of normal tension glaucoma

    Science.gov (United States)

    Guo, Xiaoli; Kimura, Atsuko; Azuchi, Yuriko; Akiyama, Goichi; Noro, Takahiko; Harada, Chikako; Namekata, Kazuhiko; Harada, Takayuki

    2016-01-01

    Glaucoma is characterized by progressive degeneration of retinal ganglion cells (RGCs) and their axons. We previously reported that loss of glutamate transporters (EAAC1 or GLAST) in mice leads to RGC degeneration that is similar to normal tension glaucoma and these animal models are useful in examining potential therapeutic strategies. Caloric restriction has been reported to increase longevity and has potential benefits in injury and disease. Here we investigated the effects of every-other-day fasting (EODF), a form of caloric restriction, on glaucomatous pathology in EAAC1−/− mice. EODF suppressed RGC death and retinal degeneration without altering intraocular pressure. Moreover, visual impairment was ameliorated with EODF, indicating the functional significance of the neuroprotective effect of EODF. Several mechanisms associated with this neuroprotection were explored. We found that EODF upregulated blood β-hydroxybutyrate levels and increased histone acetylation in the retina. Furthermore, it elevated retinal mRNA expression levels of neurotrophic factors and catalase, whereas it decreased oxidative stress levels in the retina. Our findings suggest that EODF, a safe, non-invasive, and low-cost treatment, may be available for glaucoma therapy. PMID:27669894

  18. REDES DE INTERCAMBIO DE CALOR APLICADAS A LA ESTERIFICACIÓN DE ACEITES VEGETALES USADOS

    Directory of Open Access Journals (Sweden)

    María F. Laborde

    2014-01-01

    Full Text Available E n este trabajo se presenta la aplicación de redes de intercambio de calor (RIC a la esterificación de aceites vegetales usados (AVUs con catálisis ácida para la producción de biodiesel. Se aplican distintos métodos para obtener las cantidades mínimas de calor y la RIC para una capacidad de procesamiento de 0,19 kg/s de AVUs. Se considera una diferencia de temperatura mínima (∆Tmin de 10°C y los requerimientos mínimos de calentamiento y enfriamiento, resultan ser de 4629,87 W y de 10066,30 W, respectivamente. Al aplicar la red de intercambio calórico disminuye en un 78,92% el servicio de vapor requerido en el proceso y en un 62,48% el servicio de agua de enfriamiento, lo que demuestra que la integración reduce los requerimientos energéticos respecto al proceso no integrado.

  19. Conceptos esenciales de la transmisión de calor en una edificación

    Directory of Open Access Journals (Sweden)

    Safranez, Carlos

    1981-05-01

    Full Text Available Dirigiéndose esta publicación al técnico del ramo de la Construcción, poco familiarizado con los problemas de aislamiento térmico, se presenta una breve exposición de los conceptos esenciales de la transmisión de calor en una edificación. Se exponen ejemplos del cálculo de la resistencia térmica y de la curva de temperatura de una cubierta plana y de un sótano. Se analiza la repercusión del aislamiento térmico sobre el consumo de energía con tiempo frío y tiempo caluroso. Sobre la posibilidad de producirse condensaciones, y sobre la temperatura a que estará expuesta la membrana impermeabilizante de un sótano, debido a la calefacción, con el fin de que no sobrepase los límites fijados. Finalmente, se dan a conocer dos ábacos para la determinación del coeficiente K de la transmisión de calor y de la resistencia térmica R, de distintos tipos de aislamiento.

  20. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas

    Directory of Open Access Journals (Sweden)

    Salma Abedelmalek

    2015-01-01

    Full Text Available The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg participate in this study during a period of weight maintenance (baseline and after 7 days of caloric restriction (CR. All subjects performed the Special Judo Fitness Test (SJFT during the two conditions. Values for nutrient intakes were obtained from a 7 d food record kept during a period of weight maintenance and after a 7-day food restriction (−5~6 MJ/day. Our results showed that CR resulted in significant decreases in body weight (P<0.05 and performance (P<0.05. However, heart rate and SJFT index (P<0.05 increase significantly during CR in comparison to baseline. Moreover, exercise leads to a significant increase in testosterone, cortisol, growth hormone (GH, leukocytes, neutrophils, TNF-α, and IL-6, in both CR and baseline conditions. Compared to baseline, TNF-α and IL-6 were significantly higher during CR condition (P<0.05. Additionally, CR leads to an increase in cortisol and GH (P<0.05 and a decrease in testosterone concentrations (P<0.05.

  1. Caloric restriction and resveratrol promote longevity through the Sirtuin-1-dependent induction of autophagy.

    Science.gov (United States)

    Morselli, E; Maiuri, M C; Markaki, M; Megalou, E; Pasparaki, A; Palikaras, K; Criollo, A; Galluzzi, L; Malik, S A; Vitale, I; Michaud, M; Madeo, F; Tavernarakis, N; Kroemer, G

    2010-01-01

    Caloric restriction and autophagy-inducing pharmacological agents can prolong lifespan in model organisms including mice, flies, and nematodes. In this study, we show that transgenic expression of Sirtuin-1 induces autophagy in human cells in vitro and in Caenorhabditis elegans in vivo. The knockdown or knockout of Sirtuin-1 prevented the induction of autophagy by resveratrol and by nutrient deprivation in human cells as well as by dietary restriction in C. elegans. Conversely, Sirtuin-1 was not required for the induction of autophagy by rapamycin or p53 inhibition, neither in human cells nor in C. elegans. The knockdown or pharmacological inhibition of Sirtuin-1 enhanced the vulnerability of human cells to metabolic stress, unless they were stimulated to undergo autophagy by treatment with rapamycin or p53 inhibition. Along similar lines, resveratrol and dietary restriction only prolonged the lifespan of autophagy-proficient nematodes, whereas these beneficial effects on longevity were abolished by the knockdown of the essential autophagic modulator Beclin-1. We conclude that autophagy is universally required for the lifespan-prolonging effects of caloric restriction and pharmacological Sirtuin-1 activators.

  2. Remission of anosognosia for right hemiplegia and neglect after caloric vestibular stimulation.

    Science.gov (United States)

    Ronchi, Roberta; Rode, Gilles; Cotton, François; Farnè, Alessandro; Rossetti, Yves; Jacquin-Courtois, Sophie

    2013-01-01

    Neglect and related phenomena, as anosognosia for hemiplegia and somatoparaphrenia, are often associated to right-hemisphere lesions. These deficits can be alleviated by caloric vestibular stimulation, but little is known about the efficacy of this physiological intervention on neglect following left-hemisphere lesions. Here we report the case of an ambidextrous left brain-damaged patient with severe right personal and extrapersonal neglect, anosognosia for right hemiplegia and somatoparaphrenia. These symptoms co-occurred with more typical manifestations of left-brain damage, such as aphasia and apraxia. Neurological examination revealed right hemiplegia, hemianesthesia and hemianopia. Visuo-spatial tests for personal and extrapersonal neglect, as well as an anosognosia questionnaire, were submitted before and after caloric vestibular stimulation. Results showed a dramatic improvement of anosognosia for hemiplegia and neglect; no change was observed for the remaining deficits. The results confirm the notion of the selectivity of vestibular stimulation for neglect and related disorders and extend this notion by showing that similar effects can be obtained after lesion of the left hemisphere, suggesting that similar mechanisms are responsible for left- and right-sided neglect. Such a peculiar association of language and visuo-spatial disorders jointly present after a left-sided lesion opens the question of the link between handedness and lateralization of cognitive functions.

  3. Transferencia de calor en la colada continua de aceros. I parte. El molde

    Directory of Open Access Journals (Sweden)

    Cicutti, C.

    1997-10-01

    Full Text Available The continuous casting mold plays the important role of receiving the liquid steel and allowing an uniform and defect free solidified skin to be developed. In this work, the different heat transfer mechanisms which are present from the liquid steel to the mold cooling water are reviewed. The effect of operating variables on heat extraction and the relationship between global and distributed heat flux are also analyzed.

    El molde de colada continua cumple la importante función de recibir el acero líquido y permitir que se desarrolle una capa solidificada uniforme y libre de defectos. En este trabajo se revisan los distintos mecanismos implicados en el proceso de transferencia de calor, desde el acero líquido hasta el agua de refrigeración del molde. Se analiza también el efecto de las distintas variables de funcionamiento en la extracción calórica producida y la relación entre el flujo global de calor y su distribución a lo largo del molde.

  4. Coeficientes de transferencia de calor en enfriadores de mineral laterítico a escala piloto

    Directory of Open Access Journals (Sweden)

    Ángel Legrá-Legrá

    2009-03-01

    Full Text Available En la Planta de Hornos de Reducción de la empresa niquelera Ernesto Guevara las elevadas temperaturas del mineral reducido a la salida de los enfriadores (coolers afectan el desarrollo eficiente del proceso de lixiviación. Se realizó una investigación, a escala piloto, en los enfriadores de mineral reducido con el fin de evaluar el comportamiento de los parámetros de transferencia de calor que caracterizan el proceso; para ello se registraron los valores de temperatura del agua y del flujo y la temperatura del mineral, tanto a la entrada como a la salida de la instalación, para valores de flujos de 10 y 19 l/min. Como resultado se obtuvo el procedimiento de cálculo para determinar los coeficientes superficiales de transferencia de calor por unidad de longitud. Se encontró que en los enfriadores de mineral reducido predominan la conducción y radiación del mineral a la pared interior del cilindro cubierta por el sólido así como la convección y evaporación del agua al medio que permite dirigir las acciones hacia estos elementos para aumentar la eficiencia de la instalación.

  5. Protective effects of estrogens and caloric restriction during aging on various rat testis parameters

    Institute of Scientific and Technical Information of China (English)

    Khaled Hamden; Dorothee Silandre; Christelle Delalande; Abdelfattah ElFek; Serge Carreau

    2008-01-01

    Aim: To investigate the effects of 17β-estradiol (E2), Peganum harmala extract (PHE) and caloric restriction (CR) on various testis parameters during aging. Methods: Twelve-month-old male rats were treated for 6 months with either E2 or PHE, or submitted to CR (40%). Results: Our results show that estrogens and CR are able to protect the male gonad by preventing the decrease of testosterone and E2 levels as well as the decrease of aromatase and estrogen receptor gene expressions. Indeed, E2, PHE and CR treatments induced an increase in the superoxide dismutase activities and decreased the activity of testicular enzymes: gamma-glutamyl transferase, alkaline phosphatase, lactate deshydrogenase as well as the aspartate and lactate transaminases in aged animals. In addition, the testicular catalase and gluthatione peroxidase activities were enhanced in E2, PHE and CR-treated rats compared to untreated animals at 18 months of age. Moreover, the positive effects of estradiol, PHE and CR were further supported by a lower level of lipid peroxidation. Recovery of spermatogenesis was recorded in treated rats. Conclusion: Besides a low caloric diet which is beneficial for spermatogenesis, a protective antioxydant role of estrogens is suggested. Estrogens delay testicular cell damage, which leads to functional senescence and, therefore, estrogens are helpful in protecting the reproductive functions from the adverse effects exerted by reactive oxygen species (ROS) produced in large quanti-ties in the aged testis.

  6. Mitochondrial oxidative stress, aging and caloric restriction: the protein and methionine connection.

    Science.gov (United States)

    Pamplona, Reinald; Barja, Gustavo

    2006-01-01

    Caloric restriction (CR) decreases aging rate and mitochondrial ROS (MitROS) production and oxidative stress in rat postmitotic tissues. Low levels of these parameters are also typical traits of long-lived mammals and birds. However, it is not known what dietary components are responsible for these changes during CR. It was recently observed that 40% protein restriction without strong CR also decreases MitROS generation and oxidative stress. This is interesting because protein restriction also increases maximum longevity (although to a lower extent than CR) and is a much more practicable intervention for humans than CR. Moreover, it was recently found that 80% methionine restriction substituting it for l-glutamate in the diet also decreases MitROS generation in rat liver. Thus, methionine restriction seems to be responsible for the decrease in ROS production observed in caloric restriction. This is interesting because it is known that exactly that procedure of methionine restriction also increases maximum longevity. Moreover, recent data show that methionine levels in tissue proteins negatively correlate with maximum longevity in mammals and birds. All these suggest that lowering of methionine levels is involved in the control of mitochondrial oxidative stress and vertebrate longevity by at least two different mechanisms: decreasing the sensitivity of proteins to oxidative damage, and lowering of the rate of ROS generation at mitochondria.

  7. Spatio-temporal pattern of vestibular information processing after brief caloric stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Marcelli, Vincenzo [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Esposito, Fabrizio [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Department of Cognitive Neurosciences, University of Maastricht, Maastricht (Netherlands)], E-mail: fabrizio.esposito@unina.it; Aragri, Adriana [Department of Neurological Sciences, Second University of Naples, Naples (Italy); Furia, Teresa; Riccardi, Pasquale [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Tosetti, Michela; Biagi, Laura [I.R.C.S.S. ' Stella Maris' , Pisa (Italy); Marciano, Elio [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Di Salle, Francesco [Department of Cognitive Neurosciences, University of Maastricht, Maastricht (Netherlands); I.R.C.S.S. ' Stella Maris' , Pisa (Italy); Department of Neurosciences, University of Pisa, Pisa (Italy)

    2009-05-15

    Processing of vestibular information at the cortical and subcortical level is essential for head and body orientation in space and self-motion perception, but little is known about the neural dynamics of the brain regions of the vestibular system involved in this task. Neuroimaging studies using both galvanic and caloric stimulation have shown that several distinct cortical and subcortical structures can be activated during vestibular information processing. The insular cortex has been often targeted and presented as the central hub of the vestibular cortical system. Since very short pulses of cold water ear irrigation can generate a strong and prolonged vestibular response and a nystagmus, we explored the effects of this type of caloric stimulation for assessing the blood-oxygen-level-dependent (BOLD) dynamics of neural vestibular processing in a whole-brain event-related functional magnetic resonance imaging (fMRI) experiment. We evaluated the spatial layout and the temporal dynamics of the activated cortical and subcortical regions in time-locking with the instant of injection and were able to extract a robust pattern of neural activity involving the contra-lateral insular cortex, the thalamus, the brainstem and the cerebellum. No significant correlation with the temporal envelope of the nystagmus was found. The temporal analysis of the activation profiles highlighted a significantly longer duration of the evoked BOLD activity in the brainstem compared to the insular cortex suggesting a functional de-coupling between cortical and subcortical activity during the vestibular response.

  8. Diet-beverage consumption and caloric intake among US adults, overall and by body weight.

    Science.gov (United States)

    Bleich, Sara N; Wolfson, Julia A; Vine, Seanna; Wang, Y Claire

    2014-03-01

    We examined national patterns in adult diet-beverage consumption and caloric intake by body-weight status. We analyzed 24-hour dietary recall with National Health and Nutrition Examination Survey 1999-2010 data (adults aged ≥ 20 years; n = 23 965). Overall, 11% of healthy-weight, 19% of overweight, and 22% of obese adults drink diet beverages. Total caloric intake was higher among adults consuming sugar-sweetened beverages (SSBs) compared with diet beverages (2351 kcal/day vs 2203 kcal/day; P = .005). However, the difference was only significant for healthy-weight adults (2302 kcal/day vs 2095 kcal/day; P diet beverages compared with SSBs (overweight: 1965 kcal/day vs 1874 kcal/day; P = .03; obese: 2058 kcal/day vs 1897 kcal/day; P diet-beverage consumption was 88 kilocalories for overweight and 194 kilocalories for obese adults. Overweight and obese adults drink more diet beverages than healthy-weight adults and consume significantly more solid-food calories and a comparable total calories than overweight and obese adults who drink SSBs. Heavier US adults who drink diet beverages will need to reduce solid-food calorie consumption to lose weight.

  9. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas.

    Science.gov (United States)

    Abedelmalek, Salma; Chtourou, Hamdi; Souissi, Nizar; Tabka, Zouhair

    2015-01-01

    The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg) participate in this study during a period of weight maintenance (baseline) and after 7 days of caloric restriction (CR). All subjects performed the Special Judo Fitness Test (SJFT) during the two conditions. Values for nutrient intakes were obtained from a 7 d food record kept during a period of weight maintenance and after a 7-day food restriction (-5~6 MJ/day). Our results showed that CR resulted in significant decreases in body weight (P exercise leads to a significant increase in testosterone, cortisol, growth hormone (GH), leukocytes, neutrophils, TNF-α, and IL-6, in both CR and baseline conditions. Compared to baseline, TNF-α and IL-6 were significantly higher during CR condition (P < 0.05). Additionally, CR leads to an increase in cortisol and GH (P < 0.05) and a decrease in testosterone concentrations (P < 0.05).

  10. Transferencia de calor en el secado solar a la intemperie de menas lateríticas ferroniquelíferas

    Directory of Open Access Journals (Sweden)

    Yoalbys Retirado-Mediaceja

    2011-03-01

    Full Text Available En Moa, las menas lateríticas son sometidas a secado solar a la intemperie para reducirles el contenido de humedad antes de incorporarlas al proceso de secado térmico convencional. Este artículo evalúa los procesos de transferencia de calor fundamentales que tienen lugar durante el secado natural con el propósito de determinar el modo predominante de transferencia de calor. En dos pilas de menas lateríticas expuestas a secado solar natural se midieron las variables climatológicas y termodinámicas que influyen en la transferencia de calor por convección y radiación durante el secado y se calcularon, además, los criterios adimensionales para determinar el tipo predominante de convección. Se comprobó que durante el secado solar a la intemperie predomina la convección y que en las condiciones de experimentación analizadas la radiación tuvo una incidencia secundaria. Los resultados evidenciaron que el calor se transfiere por convección libre, forzada y mixta, predominando la forzada, para la cual los coeficientes de transferencia de calor mínimos y máximos mostraron pequeñas variaciones entre ambas pilas. Los flujos de calor por convección promedios fueron 978,74 y 1 156,58 W/m2 , mientras que los flujos por radiación ascendieron a 324,71 y 355,36 W/m2 para las pilas #1 y #2, respectivamente.

  11. The calorically restricted ketogenic diet, an effective alternative therapy for malignant brain cancer

    Directory of Open Access Journals (Sweden)

    Zhou Weihua

    2007-02-01

    Full Text Available Abstract Background Malignant brain cancer persists as a major disease of morbidity and mortality in adults and is the second leading cause of cancer death in children. Many current therapies for malignant brain tumors fail to provide long-term management because they ineffectively target tumor cells while negatively impacting the health and vitality of normal brain cells. In contrast to brain tumor cells, which lack metabolic flexibility and are largely dependent on glucose for growth and survival, normal brain cells can metabolize both glucose and ketone bodies for energy. This study evaluated the efficacy of KetoCal®, a new nutritionally balanced high fat/low carbohydrate ketogenic diet for children with epilepsy, on the growth and vascularity of a malignant mouse astrocytoma (CT-2A and a human malignant glioma (U87-MG. Methods Adult mice were implanted orthotopically with the malignant brain tumors and KetoCal® was administered to the mice in either unrestricted amounts or in restricted amounts to reduce total caloric intake according to the manufacturers recommendation for children with refractory epilepsy. The effects KetoCal® on tumor growth, vascularity, and mouse survival were compared with that of an unrestricted high carbohydrate standard diet. Results KetoCal® administered in restricted amounts significantly decreased the intracerebral growth of the CT-2A and U87-MG tumors by about 65% and 35%, respectively, and significantly enhanced health and survival relative to that of the control groups receiving the standard low fat/high carbohydrate diet. The restricted KetoCal® diet reduced plasma glucose levels while elevating plasma ketone body (β-hydroxybutyrate levels. Tumor microvessel density was less in the calorically restricted KetoCal® groups than in the calorically unrestricted control groups. Moreover, gene expression for the mitochondrial enzymes, β-hydroxybutyrate dehydrogenase and succinyl-CoA: 3-ketoacid Co

  12. Transient regional osteoporosis.

    Science.gov (United States)

    Cano-Marquina, Antonio; Tarín, Juan J; García-Pérez, Miguel-Ángel; Cano, Antonio

    2014-04-01

    Transient regional osteoporosis (TRO) is a disease that predisposes to fragility fracture in weight bearing joints of mid-life women and men. Pregnant women may also suffer the process, usually at the hip. The prevalence of TRO is lower than the systemic form, associated with postmenopause and advanced age, but may be falsely diminished by under-diagnosis. The disease may be uni- or bilateral, and may migrate to distinct joints. One main feature of TRO is spontaneous recovery. Pain and progressive limitation in the functionality of the affected joint(s) are key symptoms. In the case of the form associated with pregnancy, difficulties in diagnosis derive from the relatively young age at presentation and from the clinical overlapping with the frequent aches during gestation. Densitometric osteoporosis in the affected region is not always present, but bone marrow edema, with or without joint effusion, is detected by magnetic resonance. There are not treatment guidelines, but the association of antiresorptives to symptomatic treatment seems to be beneficial. Surgery or other orthopedic interventions can be required for specific indications, like hip fracture, intra-medullary decompression, or other.

  13. Applied hydraulic transients

    CERN Document Server

    Chaudhry, M Hanif

    2014-01-01

    This book covers hydraulic transients in a comprehensive and systematic manner from introduction to advanced level and presents various methods of analysis for computer solution. The field of application of the book is very broad and diverse and covers areas such as hydroelectric projects, pumped storage schemes, water-supply systems, cooling-water systems, oil pipelines and industrial piping systems. Strong emphasis is given to practical applications, including several case studies, problems of applied nature, and design criteria. This will help design engineers and introduce students to real-life projects. This book also: ·         Presents modern methods of analysis suitable for computer analysis, such as the method of characteristics, explicit and implicit finite-difference methods and matrix methods ·         Includes case studies of actual projects ·         Provides extensive and complete treatment of governed hydraulic turbines ·         Presents design charts, desi...

  14. The Rapid Transient Surveyor

    CERN Document Server

    Baranec, Christoph; Wright, Shelley A; Tonry, John; Tully, R Brent; Szapudi, István; Takamiya, Marianne; Hunter, Lisa; Riddle, Reed; Chen, Shaojie; Chun, Mark

    2016-01-01

    The Rapid Transient Surveyor (RTS) is a proposed rapid-response, high-cadence adaptive optics (AO) facility for the UH 2.2-m telescope on Maunakea. RTS will uniquely address the need for high-acuity and sensitive near-infrared spectral follow-up observations of tens of thousands of objects in mere months by combining an excellent observing site, unmatched robotic observational efficiency, and an AO system that significantly increases both sensitivity and spatial resolving power. We will initially use RTS to obtain the infrared spectra of ~4,000 Type Ia supernovae identified by the Asteroid Terrestrial-Impact Last Alert System over a two year period that will be crucial to precisely measuring distances and mapping the distribution of dark matter in the z < 0.1 universe. RTS will comprise an upgraded version of the Robo-AO laser AO system and will respond quickly to target-of-opportunity events, minimizing the time between discovery and characterization. RTS will acquire simultaneous-multicolor images with a...

  15. The rapid transient surveyor

    Science.gov (United States)

    Baranec, C.; Lu, J. R.; Wright, S. A.; Tonry, J.; Tully, R. B.; Szapudi, I.; Takamiya, M.; Hunter, L.; Riddle, R.; Chen, S.; Chun, M.

    2016-07-01

    The Rapid Transient Surveyor (RTS) is a proposed rapid-response, high-cadence adaptive optics (AO) facility for the UH 2.2-m telescope on Maunakea. RTS will uniquely address the need for high-acuity and sensitive near-infrared spectral follow-up observations of tens of thousands of objects in mere months by combining an excellent observing site, unmatched robotic observational efficiency, and an AO system that significantly increases both sensitivity and spatial resolving power. We will initially use RTS to obtain the infrared spectra of 4,000 Type Ia supernovae identified by the Asteroid Terrestrial-Impact Last Alert System over a two year period that will be crucial to precisely measuring distances and mapping the distribution of dark matter in the z efficiency prism integral field unit spectrograph: R = 70-140 over a total bandpass of 840-1830nm with an 8.7" by 6.0" field of view (0.15" spaxels). The AO correction boosts the infrared point-source sensitivity of the spectrograph against the sky background by a factor of seven for faint targets, giving the UH 2.2-m the H-band sensitivity of a 5.7-m telescope without AO.

  16. Latent heat loss of Holstein cows in a tropical environment: a prediction model Perda de calor latente em vacas Holandesas em ambiente tropical: um modelo de predição

    Directory of Open Access Journals (Sweden)

    Alex Sandro Campos Maia

    2008-10-01

    maior peso corporal (classe 2 e 3 apresentaram maiores taxas evaporativas. Quando a temperatura do ar aumentou de 10 para 36ºC e a umidade relativa do ar caiu de 90 para 30%, a eliminação de calor por evaporação respiratória aumentou de aproximadamente 5 para 57 W m-2 e a evaporação na superfície corporal passou de 30 para 350 W m-2. Esses resultados confirmam que a eliminação de calor latente é o principal mecanismo de perda de energia térmica sob altas temperaturas (>30ºC; a evaporação cutânea é a maior via e corresponde a aproximadamente 85% da perda total de calor, enquanto o restante é eliminado pelo sistema respiratório. O modelo para predizer o fluxo de perda de calor latente baseado em variáveis fisiológicas e ambientais pode ser utilizado para estimar a contribuição da evaporação na termorregulação, enquanto o modelo baseado somente na temperatura do ar deve ser usado apenas para a simples caracterização do processo evaporativo.

  17. Influencia del contexto hidrogeológico en la eficiencia de los sistemas cerrados de bomba de calor

    OpenAIRE

    Folch Sancho, Albert; Goma Roca, Albert; Jimenez Parras, Santos; Zarroca HErnandez, Mario; Bach Plaza, Joan; Mas Pla, Josep

    2013-01-01

    Los sistemas geotérmicos de bomba de calor se caracterizan por presentar una elevada eficiencia energética en condiciones de óptimo funcionamiento. Aun así, su productividad se ve condicionada por las características geológicas e hidrogeológicas del medio. El presente estudio centra su interés en los sistemas cerrados verticales, dado que en muchos casos no se contabiliza el efecto del flujo de agua subterránea de forma adecuada. En este trabajo se evalúa el transporte de calor en 4 contextos...

  18. PROCEDIMIENTO DE CALIBRACIÓN EN TEMPERATURA Y FLUJO DE CALOR DE UN CALORÍMETRO DIFERENCIAL DE BARRIDO (DSC)

    OpenAIRE

    Pablo E. Reynoso; Claudio A. Danón

    2016-01-01

    El calorímetro diferencial de barrido no es un dispositivo de medición absoluta, por lo que su utilización requiere indispensable mente una calibración. En esta contribución se presenta un procedimiento de calibración para el cual s e consideraron las temperaturas y calores de fusión aceptados en la literatura de 5 materiales puros . S e prepararon 6 muestras de dife rentes masas para cada material y s e sometió cada una de ellas a ci clos de calentamiento ,...

  19. Transferencia de calor en el secado solar a la intemperie de menas lateríticas ferroniquelíferas

    OpenAIRE

    Yoalbys Retirado-Mediaceja; Marbelis Lamorú-Urgelles; Ever Góngora-Leyva; Enrique Torres-Tamayo; Benigno Leyva-de la Cruz; Daynelis García-Batista

    2011-01-01

    En Moa, las menas lateríticas son sometidas a secado solar a la intemperie para reducirles el contenido de humedad antes de incorporarlas al proceso de secado térmico convencional. Este artículo evalúa los procesos de transferencia de calor fundamentales que tienen lugar durante el secado natural con el propósito de determinar el modo predominante de transferencia de calor. En dos pilas de menas lateríticas expuestas a secado solar natural se midieron las variables climatológicas y termodinám...

  20. Transferencia de calor en el secado solar a la intemperie de menas lateríticas ferroniquelíferas

    OpenAIRE

    Yoalbys Retirado-Mediaceja; Marbelis Lamorú-Urgelles; Ever Góngora-Leyva; Enrique Torres-Tamayo; Benigno Leyva-de la Cruz; Daynelis García-Batista

    2011-01-01

    En Moa, las menas lateríticas son sometidas a secado solar a la intemperie para reducirles el contenido de humedad antes de incorporarlas al proceso de secado térmico convencional. Este artículo evalúa los procesos de transferencia de calor fundamentales que tienen lugar durante el secado natural con el propósito de determinar el modo predominante de transferencia de calor. En dos pilas de menas lateríticas expuestas a secado solar natural se midieron las variables climatológicas y termodinám...

  1. Caloric Intake from Fast Food among Children and Adolescents in the United States, 2011-2012. NCHS Data Brief. Number 213

    Science.gov (United States)

    Vikraman, Sundeep; Fryar, Cheryl D.; Ogden, Cynthia L.

    2015-01-01

    Consumption of fast food has been linked to weight gain in adults. Fast food has also been associated with higher caloric intake and poorer diet quality in children and adolescents. From 1994 through 2006, caloric intake from fast food increased from 10% to 13% among children aged 2-18 years. This report presents the most recent data on the…

  2. Isotermas e calor isostérico de sorção do feijão Isotherms and isosteric heats of sorptions of the edible bean

    Directory of Open Access Journals (Sweden)

    Osvaldo Resende

    2006-09-01

    Full Text Available O teor de água de equilíbrio dos grãos de feijão foi determinado pelo método dinâmico-gravimétrico para temperaturas entre 25 e 55 °C e atividades de água para cada temperatura, entre 0,20 e 0,75. Observou-se que o teor de água decresce com o aumento da temperatura para uma dada atividade de água à semelhança dos produtos higroscópicos. Aos dados experimentais foram ajustados diversos modelos matemáticos disponíveis na literatura (Brunauer-Emmett-Teller, Chung Pfost, Copace, Guggenhein-Anderson-de Boer, Halsey Modificado, Henderson, Henderson Modificado, Oswin, Sabbah e Sigma Copace. Segundo os parâmetros estatísticos de análise, o modelo de Halsey Modificado foi o que descreveu melhor a higroscopicidade do feijão. A partir dos resultados obtidos calculou-se o calor isostérico para cada teor de água de equilíbrio. Observou-se que o calor isostérico aumenta com a diminuição do conteúdo de água do produto, indicando que a redução do teor de água aumenta a energia necessária para a remoção de água. Os valores de calor isostérico para os grãos de feijão na faixa de umidade de 10,10 a 21,71 (% b.s., variam de 3961 a 2718 kJ kg-1.The equilibrium moisture content of the edible bean was determined using the dynamic-gravimetric method for temperatures between 25 and 55 °C and water activity between 0.20 and 0.75. It was observed that the moisture content decreases when the temperature for a given water activity is increased. Experimental data were adjusted to mathematical models mentioned in the specific literature (Brunauer-Emmett-Teller, Chung Pfost, Copace, Guggenhein-Anderson-de Boer, Modified Halsey, Henderson, Modified Henderson, Oswin, Sabbah and Sigma Copace. According to the results obtained and statistical parameters, the Modified Halsey model was the most effective in representing the hygroscopicity of the edible bean. From the obtained results, the desorption isosteric heats for each equilibrium moisture

  3. Helioseismic Effects of Energetic Transients

    Indian Academy of Sciences (India)

    Ashok Ambastha

    2008-03-01

    Photospheric and chromospheric signatures related to large, energetic transients such as flares and CMEs, have been extensively reported during the last several years. In addition, energetic solar transients are expected to cause helioseismic effects. Some of the recent results are reviewed here; in particular, the helioseismic effects of the powerful flares in superactive region, NOAA 10486, including the 4B/X17 superflare of October 28, 2003. We also examine the temporal variations of power in low- modes during the period May 1995–October 2005, and compare with daily, disk-integrated flare- and CME-indices to infer the effect of transients on the scale of whole solar disk.

  4. Electromagnetic transients in power cables

    CERN Document Server

    da Silva, Filipe Faria

    2013-01-01

    From the more basic concepts to the most advanced ones where long and laborious simulation models are required, Electromagnetic Transients in Power Cables provides a thorough insight into the study of electromagnetic transients and underground power cables. Explanations and demonstrations of different electromagnetic transient phenomena are provided, from simple lumped-parameter circuits to complex cable-based high voltage networks, as well as instructions on how to model the cables.Supported throughout by illustrations, circuit diagrams and simulation results, each chapter contains exercises,

  5. Transient or permanent fisheye views

    DEFF Research Database (Denmark)

    Jakobsen, Mikkel Rønne; Hornbæk, Kasper

    2012-01-01

    , about the benefits and limitations of transient visualizations. We describe an experiment that compares the usability of a fisheye view that participants could call up temporarily, a permanent fisheye view, and a linear view: all interfaces gave access to source code in the editor of a widespread......Transient use of information visualization may support specific tasks without permanently changing the user interface. Transient visualizations provide immediate and transient use of information visualization close to and in the context of the user’s focus of attention. Little is known, however...... programming environment. Fourteen participants performed varied tasks involving navigation and understanding of source code. Participants used the three interfaces for between four and six hours in all. Time and accuracy measures were inconclusive, but subjective data showed a preference for the permanent...

  6. Transient heating of moving objects

    Directory of Open Access Journals (Sweden)

    E.I. Baida

    2014-06-01

    Full Text Available A mathematical model of transient and quasistatic heating of moving objects by various heat sources is considered. The mathematical formulation of the problem is described, examples of thermal calculation given.

  7. Voltage dependence of Na translocation by the Na/K pump.

    Science.gov (United States)

    Nakao, M; Gadsby, D C

    During each complete reaction cycle, the Na/K pump transports three Na ions out across the cell membrane and two K ions in. The resulting net extrusion of positive charge generates outward membrane current but, until now, it was unclear how that net charge movement occurs. Reasonable possibilities included a single positive charge moving outwards during Na translocation; or a single negative charge moving inwards during K translocation; or either positive or negative charges moving during both translocation steps, but in unequal quantities. Any step that involves net charge movement through the membrane must have voltage-dependent transition rates. Here we report measurements of transient, voltage-dependent, displacement currents generated by the pump when its normal Na/K transport cycle has been interrupted by removal of external K and it is thus constrained to carry out Na/Na exchange. The quantity and voltage sensitivity of the charge moved during these transient currents suggests that Na translocation includes a voltage-dependent transition involving movement of one positive charge across the membrane. This single step can thus fully account for the electrogenic nature of Na/K exchange. The result provides important new insight into the molecular mechanism of active cation transport.

  8. Comparison of Vestibular Evoked Myogenic Potential and Caloric Tests Findings in Noise Induced Hearing Loss-Affected and Healthy Individuals

    Directory of Open Access Journals (Sweden)

    Farinoosh Fakharnia

    2010-06-01

    Full Text Available Background and Aim: Balance disturbance is one of the non-auditory effects of noisy industrial environments that is usually neglected. The aim of the current study was to investigate the effect of occupational noise on vestibular system among workers with noise-induced hearing loss (NIHL, based on both vestibular evoked myogenic potentials (VEMP and caloric tests.Methods: Thirty male workers with noise-induced hearing loss and thirty male matched controls were examined by VEMP and caloric tests. Study parameters included unilateral weakness, p13 and n23 latencies, and p13-n23 amplitude. Caloric test was performed only for 20 patients.Results: No significant difference was observed in unilateral weakness between the two groups. On the other hand, the difference in mean latencies of p13 in the right ear (p=0.003 and left ear (p=0.01 was significant between the two groups. However, the difference in n23 latency was significant only in the right ear (p=0.03. There was no significant difference between groups in p13-n23 amplitude.Conclusion: It seems that pars inferior of vestibule is the susceptible part in individuals with NIHL. In general, abnormal findings in both VEMP and caloric tests were more common compared to functional symptoms such as vertigo, which may be due to central compensation and the symmetry of the disorder.

  9. A two year randomized controlled trial of human caloric restriction: feasibility and effects on predictors of health span and longevity

    Science.gov (United States)

    Background: Caloric restriction (CR), energy intake reduced below ad libitum (AL) intake, increases life span in many species. The implications for humans can be clarified by randomized controlled trials of CR. Methods: To determine CRs feasibility, safety, and effects on predictors of longevity, di...

  10. Cardiovascular flexibility in middle-aged overweight South Asians vs. white Caucasians: response to short-term caloric restriction

    NARCIS (Netherlands)

    Schinkel, L.D. van; Bakker, L.E.; Jonker, J.T.; Roos, A. de; Pijl, H.; Meinders, A.E.; Jazet, I.M.; Lamb, H.J.; Smit, J.W.A.

    2015-01-01

    BACKGROUND AND AIMS: South Asians have a higher risk of developing cardiovascular disease than white Caucasians. The underlying cause is unknown, but might be related to higher cardiac susceptibility to metabolic disorders. Short-term caloric restriction (CR) can be used as a metabolic stress test t

  11. Caloric test and video-head-impulse: a study of vertigo/dizziness patients in a community hospital.

    Science.gov (United States)

    Mahringer, Andrea; Rambold, Holger A

    2014-03-01

    The head-impulse test (HIT) is an important test for examining unilateral vestibular hypofunction. The new video-head-impulse test (vHIT) is more sensitive and specific than the clinical bedside-head-impulse test (bHIT). Alternatively, one can test for vestibular hypofunction with the caloric irrigation test. Various studies showed that both tests may not always identify vestibular hypofunction; instead, the results of the tests might be contradictory. To evaluate the diagnostic value of these tests, we routinely measured patients exhibiting vertigo or dizziness at our community hospital with bithermal caloric irrigation, the bHIT and the vHIT. Only those patients (n = 172) with a pathological caloric irrigation test of more than 25 % unilateral weakness in the Jongkee's formula were included. Out of these patients, 41 % had a pathologic vHIT. Among the subgroup with acute symptoms (symptom onset within 5 days), 63 % had a pathological video-head-impulse, whereas only 33 % of the non-acute group (symptom onset more than 5 days) tested pathological. A pathological HIT depended on the disease stage, the amount of unilateral weakness in caloric examination and on the test itself.

  12. Exercise and Caloric Restriction Alter the Immune System of Mice Submitted to a High-Fat Diet

    Directory of Open Access Journals (Sweden)

    Frederick Wasinski

    2013-01-01

    Full Text Available As the size of adipocytes increases during obesity, the establishment of resident immune cells in adipose tissue becomes an important source of proinflammatory mediators. Exercise and caloric restriction are two important, nonpharmacological tools against body mass increase. To date, their effects on the immune cells of adipose tissue in obese organisms, specifically when a high-fat diet is consumed, have been poorly investigated. Thus, after consuming a high-fat diet, mice were submitted to chronic swimming training or a 30% caloric restriction in order to investigate the effects of both interventions on resident immune cells in adipose tissue. These strategies were able to reduce body mass and resulted in changes in the number of resident immune cells in the adipose tissue and levels of cytokines/chemokines in serum. While exercise increased the number of NK cells in adipose tissue and serum levels of IL-6 and RANTES, caloric restriction increased the CD4+/CD8+ cell ratio and MCP-1 levels. Together, these data demonstrated that exercise and caloric restriction modulate resident immune cells in adipose tissues differently in spite of an equivalent body weight reduction. Additionally, the results also reinforce the idea that a combination of both strategies is better than either individually for combating obesity.

  13. Caloric Restriction in Lean and Obese Strains of Laboratory Rat: Effects on Body Composition, Metabolism, Growth, and Overall Health

    Science.gov (United States)

    NEW FINDINGS: What is the central question of this study? How do lean and obese rats respond physiologically to caloric restriction? What is the main finding and its importance? Obese rats show marked benefits compared with lean animals. Reduced body fat is associated with improv...

  14. Cardiovascular flexibility in middle-aged overweight South Asians vs. white Caucasians: response to short-term caloric restriction

    NARCIS (Netherlands)

    Schinkel, L.D. van; Bakker, L.E.; Jonker, J.T.; Roos, A. de; Pijl, H.; Meinders, A.E.; Jazet, I.M.; Lamb, H.J.; Smit, J.W.A.

    2015-01-01

    BACKGROUND AND AIMS: South Asians have a higher risk of developing cardiovascular disease than white Caucasians. The underlying cause is unknown, but might be related to higher cardiac susceptibility to metabolic disorders. Short-term caloric restriction (CR) can be used as a metabolic stress test

  15. Behavioural changes are a major contributing factor in the reduction of sarcopenia in caloric-restricted ageing mice

    NARCIS (Netherlands)

    Norren, van K.; Rusli, F.; Dijk, van M.; Lute, C.; Nagel, J.C.; Dijk, F.J.; Dwarkasing, J.T.; Boekschoten, M.V.; Luiking, Y.; Witkamp, R.F.; Müller, M.R.; Steegenga, W.T.

    2015-01-01

    Background - In rodent models, caloric restriction (CR) with maintenance of adequate micronutrient supply has been reported to increase lifespan and to reduce age-induced muscle loss (sarcopenia) during ageing. In the present study, we further investigated effects of CR on the onset and severity of

  16. Short-term caloric restriction normalizes hypothalamic neuronal responsiveness to glucose ingestion in patients with type 2 diabetes

    NARCIS (Netherlands)

    Teeuwisse, W.M.; Widya, R.L.; Paulides, M.; Lamb, H.J.; Smit, J.W.A.; Roos, A. de; Buchem, M.A. van; Pijl, H.; Grond, J. van der

    2012-01-01

    The hypothalamus is critically involved in the regulation of feeding. Previous studies have shown that glucose ingestion inhibits hypothalamic neuronal activity. However, this was not observed in patients with type 2 diabetes. Restoring energy balance by reducing caloric intake and losing weight are

  17. Chaos theory applied to the caloric response of the vestibular system.

    Science.gov (United States)

    Aasen, T

    1993-12-01

    Developments in the field of nonlinear dynamics has given us a new conceptual framework for understanding the mechanisms involved in the regulation of complex nonlinear systems. This concept, called "chaos" or "deterministic chaos," has been applied to EKG, EEG, and other physiological signals, but not yet to the ENG signal. The underlying geometrical structure in chaotic dynamics is fractal (noninteger dimension), and calculating the fractal dimension of the electronystagmographic recording from caloric testing gave a dimension ranging from 3.3 to 7.7. This result demonstrates that the multidimensional vestibular system, with its numerous neurological pathways, can somehow reduce the degrees of freedom and give rise to an irregular dynamic low-dimensional behavior, which is associated with deterministic chaos.

  18. Achieving tailorable magneto-caloric effect in the Gd-Co binary amorphous alloys

    Directory of Open Access Journals (Sweden)

    C. Wu

    2016-03-01

    Full Text Available Tailorable magnetic properties and magneto-caloric effect were achieved in the Gd-Co binary amorphous alloys. It was found that the Curie temperature (Tc of the GdxCo100-x (x=50, 53, 56, 58, 60 metallic glasses can be tuned by changing the concentration of Gd as Tc =708.8-8.83x, and the mechanism involved was investigated. On the other hand, a linear correlation between the peak value of magnetic entropy change (-Δ Smpeak and Tc-2/3 is found in the amorphous alloys with a linear correlation coefficients of above 0.992. Therefore, the -ΔSmpeak of the Gd-Co binary amorphous alloys under different magnetic fields can be easily tailored by adjusting the composition of the alloy.

  19. Aging and Caloric Restriction Research: A Biological Perspective With Translational Potential

    Directory of Open Access Journals (Sweden)

    Priya Balasubramanian

    2017-07-01

    Full Text Available Aging as a research pursuit is fairly new compared with traditional lines of medical research. A growing field of investigators is focused on understanding how changes in tissue biology, physiology, and systemic homeostasis, conspire to create increased vulnerability to disease as a function of age. Aging research as a discipline is necessarily broad; in part because aging itself is multi-faceted and in part because different model systems are employed to define the underlying biology. In this review we outline aspects of aging research that are likely to uncover the pivotal events leading to age-related disease vulnerability. We focus on studies of human aging and discuss the value of research on caloric restriction, an intervention with proven efficacy in delaying aging. We propose that studies such as these will deliver target factors and processes that create vulnerability in human aging, an advance that would potentially be transformative in clinical care.

  20. Using Light Charged Particles to Probe the Asymmetry Dependence of the Nuclear Caloric Curve

    CERN Document Server

    McIntosh, Alan B; Kohley, Zachary; Cammarata, Paul J; Hagel, Kris; Heilborn, Lauren; Mabiala, Justin; May, Larry W; Marini, Paola; Raphelt, Andrew; Souliotis, George A; Wuenschel, Sara; Zarrella, Andrew; Yennello, Sherry J

    2013-01-01

    Recently, we observed a clear dependence of the nuclear caloric curve on neutron-proton asymmetry $\\frac{N-Z}{A}$ through examination of fully reconstructed equilibrated quasi-projectile sources produced in heavy ion collisions at E/A = 35 MeV. In the present work, we extend our analysis using multiple light charged particle probes of the temperature. Temperatures are extracted with five distinct probes using a kinetic thermometer approach. Additionally, temperatures are extracted using two probes within a chemical thermometer approach (Albergo method). All seven measurements show a significant linear dependence of the source temperature on the source asymmetry. For the kinetic thermometer, the strength of the asymmetry dependence varies with the probe particle species in a way which is consistent with an average emission-time ordering.

  1. Hypophosphatemia and neurological changes secondary to oral caloric intake: a variant of hyperalimentation syndrome.

    Science.gov (United States)

    Silvis, S E; DiBartolomeo, A G; Aaker, H M

    1980-03-01

    Previous reports have described a syndrome of paresthesias, weakness, seizures and hypophosphatemia in patients and animals receiving intravenous hyperalimentation. In this report we describe a group of five patients who developed this syndrome while on oral caloric intake and three patients who received only modest amounts of hyperalimentation therapy. As an experimental corollary, studies were performed in starved and normal dogs with calories infused via an intragastric catheter. The serum inorganic phosphorus (Pi) fell slightly in normal animals from 4.8-2.5 mg. %. In the starved dogs with diarrhea or vomiting the Pi fell gradually from 4.8-1.6. In starved dogs without gastrointestinal symptoms the Pi fell precipitously from 3.7-1.4 mg % on the first day of infusion and remained at that level. Approximately 50% of the starved animals developed the neurological syndrome; none of the normal animals had neurological symptoms.

  2. Análise da transferência de calor em coberturas com barreiras radiantes

    OpenAIRE

    Michels, Caren

    2007-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Civil. Nas cidades brasileiras o maior ganho térmico de edificações térreas ocorre pelo telhado. Assim, o emprego de barreiras radiantes tem a função de minimizar o fluxo de calor que atravessa o sistema de cobertura. Apesar da utilização deste tipo de isolante térmico ter crescido nos últimos anos, ainda não existem normas técnicas que tratem do assunto. Conseqüent...

  3. Caloric restriction suppresses apoptotic cell death in the mammalian cochlea and leads to prevention of presbycusis.

    Science.gov (United States)

    Someya, Shinichi; Yamasoba, Tatsuya; Weindruch, Richard; Prolla, Tomas A; Tanokura, Masaru

    2007-10-01

    Presbycusis is characterized by an age-related progressive decline of auditory function, and arises mainly from the degeneration of hair cells or spiral ganglion (SG) cells in the cochlea. Here we show that caloric restriction suppresses apoptotic cell death in the mouse cochlea and prevents late onset of presbycusis. Calorie restricted (CR) mice, which maintained body weight at the same level as that of young control (YC) mice, retained normal hearing and showed no cochlear degeneration. CR mice also showed a significant reduction in the number of TUNEL-positive cells and cleaved caspase-3-positive cells relative to middle-age control (MC) mice. Microarray analysis revealed that CR down-regulated the expression of 24 apoptotic genes, including Bak and Bim. Taken together, our findings suggest that loss of critical cells through apoptosis is an important mechanism of presbycusis in mammals, and that CR can retard this process by suppressing apoptosis in the inner ear tissue.

  4. The effect of non-caloric sweeteners on cognition, choice, and post-consumption satisfaction.

    Science.gov (United States)

    Hill, Sarah E; Prokosch, Marjorie L; Morin, Amanda; Rodeheffer, Christopher D

    2014-12-01

    Consumers often turn to non-caloric sweeteners (NCS) as a means of promoting a healthy body weight. However, several studies have now linked their long-term use to increased weight gain, raising the question of whether these products produce unintended psychological, physiological, or behavioral changes that have implications for weight management goals. In the following, we present the results of three experiments bearing on this issue, testing whether NCS-consumption influences how individuals think about and respond to food. Participants in each of our three experiments were randomly assigned to consume a sugar-sweetened beverage, an unsweetened beverage, or a beverage sweetened with NCS. We then measured their cognition (Experiment 1), product choice (Experiment 2), and subjective responses to a sugar-sweetened food (Experiment 3). Results revealed that consuming NCS-sweetened beverages influences psychological processes in ways that - over time - may increase calorie intake.

  5. Amorphization Induced High Magneto-Caloric Effect of Gd55A120Ni25 Ternary Alloy

    Institute of Scientific and Technical Information of China (English)

    DING Ding; XIA Lei; YU Zhong-Hua; DONG Yuan-Da

    2008-01-01

    We report the amorphization induced high magneto-caloric effect (MCE) of recently developed Gd55Al15Ni30 bulk metallic glass (BMG). The magnetic properties of the Gd55Al15Ni30 BMG are investigated in comparison with that of its crystalline counterpart. It is found that amorphization can increase the saturation magnetization and decrease the hysteresis of Gd55Al15Ni30 alloys, which indicate the possible enhancement of MCE. The magnetic entropy changes and the refrigerant capacity of the BMG as well as the crystalline samples is calculated directly from isothermal magnetic measurements. The results show the amorphization induced high MCE of the alloy and the excellent refrigerant efficiency of Gd55A115Ni30 bulk metallic glass.

  6. Repletion of TNFα or leptin in calorically restricted mice suppresses post-restriction hyperphagia

    Science.gov (United States)

    Hambly, Catherine; Duncan, Jacqueline S.; Archer, Zoë A.; Moar, Kim M.; Mercer, Julian G.; Speakman, John R.

    2012-01-01

    SUMMARY The causes of post-restriction hyperphagia (PRH) represent a target for drug-based therapies to prevent obesity. However, the factors causing PRH are poorly understood. We show that, in mice, the extent of PRH was independent of the time under restriction, but depended on its severity, suggesting that PRH was driven by signals from altered body composition. Signals related to fat mass were important drivers. Circulating levels of leptin and TNFα were significantly depleted following caloric restriction (CR). We experimentally repleted their levels to match those of controls, and found that in both treatment groups the level of PRH was significantly blunted. These data establish a role for TNFα and leptin in the non-pathological regulation of energy homeostasis. Signals from adipose tissue, including but not limited to leptin and TNFα, regulate PRH and might be targets for therapies that support people engaged in CR to reduce obesity. PMID:21954068

  7. Higher Caloric Refeeding Is Safe in Hospitalised Adolescent Patients with Restrictive Eating Disorders

    Directory of Open Access Journals (Sweden)

    Elizabeth K. Parker

    2016-01-01

    Full Text Available Introduction. This study examines weight gain and assesses complications associated with refeeding hospitalised adolescents with restrictive eating disorders (EDs prescribed initial calories above current recommendations. Methods. Patients admitted to an adolescent ED structured “rapid refeeding” program for >48 hours and receiving ≥2400 kcal/day were included in a 3-year retrospective chart review. Results. The mean (SD age of the 162 adolescents was 16.7 years (0.9, admission % median BMI was 80.1% (10.2, and discharge % median BMI was 93.1% (7.0. The mean (SD starting caloric intake was 2611.7 kcal/day (261.5 equating to 58.4 kcal/kg (10.2. Most patients (92.6% were treated with nasogastric tube feeding. The mean (SD length of stay was 3.6 weeks (1.9, and average weekly weight gain was 2.1 kg (0.8. No patients developed cardiac signs of RFS or delirium; complications included 4% peripheral oedema, 1% hypophosphatemia (<0.75 mmol/L, 7% hypomagnesaemia (<0.70 mmol/L, and 2% hypokalaemia (<3.2 mmol/L. Caloric prescription on admission was associated with developing oedema (95% CI 1.001 to 1.047; p=0.039. No statistical significance was found between electrolytes and calories provided during refeeding. Conclusion. A rapid refeeding protocol with the inclusion of phosphate supplementation can safely achieve rapid weight restoration without increased complications associated with refeeding syndrome.

  8. Cognitive Performances Are Selectively Enhanced during Chronic Caloric Restriction or Resveratrol Supplementation in a Primate

    Science.gov (United States)

    Marchal, Julia; Picq, Jean-Luc; Aujard, Fabienne

    2011-01-01

    Effects of an 18-month treatment with a moderate, chronic caloric restriction (CR) or an oral supplementation with resveratrol (RSV), a potential CR mimetic, on cognitive and motor performances were studied in non-human primates, grey mouse lemurs (Microcebus murinus). Thirty-three adult male mouse lemurs were assigned to three different groups: a control (CTL) group fed ad libitum, a CR group fed 70% of the CTL caloric intake, and an RSV group (RSV supplementation of 200 mg.kg−1.day−1) fed ad libitum. Three different cognitive tests, two motor tests, one emotional test and an analysis of cortisol level were performed in each group. Compared to CTL animals, CR or RSV animals did not show any change in motor performances evaluated by rotarod and jump tests, but an increase in spontaneous locomotor activity was observed in both groups. Working memory was improved by both treatments in the spontaneous alternation task. Despite a trend for CR group, only RSV supplementation increased spatial memory performances in the circular platform task. Finally, none of these treatments induced additional stress to the animals as reflected by similar results in the open field test and cortisol analyses compared to CTL animals. The present data provided the earliest evidence for a beneficial effect of CR or RSV supplementation on specific cognitive functions in a primate. Taken together, these results suggest that RSV could be a good candidate to mimic long-term CR effects and support the growing evidences that nutritional interventions can have beneficial effects on brain functions even in adults. PMID:21304942

  9. Acute caloric restriction counteracts hepatic bile acid and cholesterol deficiency in morbid obesity.

    Science.gov (United States)

    Straniero, S; Rosqvist, F; Edholm, D; Ahlström, H; Kullberg, J; Sundbom, M; Risérus, U; Rudling, M

    2017-05-01

    Bile acid (BA) synthesis is regulated by BA signalling in the liver and by fibroblast growth factor 19 (FGF19), synthesized and released from the intestine. In morbid obesity, faecal excretion and hepatic synthesis of BAs and cholesterol are strongly induced and caloric restriction reduces their faecal excretion considerably. We hypothesized that the high intestinal food mass in morbidly obese subjects promotes faecal excretion of BAs and cholesterol, thereby creating a shortage of both BAs and cholesterol in the liver. Ten morbidly obese women (BMI 42 ± 2.6 kg m(-2) ) were monitored on days 0, 3, 7, 14 and 28 after beginning a low-calorie diet (800-1100 kcal day(-1) ). Serum was collected and liver size and fat content determined. Synthesis of BAs and cholesterol was evaluated from serum markers, and the serum levels of lipoproteins, BAs, proprotein convertase subtilisin/kexin type 9 (PCSK9), insulin, glucose and FGF19 were monitored. Fifty-four nonobese women (BMI cholesterol and serum levels of BAs and PCSK9 were elevated in the obese group compared to controls. Already after 3 days on a low-calorie diet, BA and cholesterol synthesis and serum BA and PCSK9 levels normalized, whereas LDL cholesterol increased. FGF19 and triglyceride levels were unchanged, and liver volume was reduced by 10%. The results suggest that hepatic BAs and cholesterol are deficient in morbid obesity. Caloric restriction rapidly counteracts these deficiencies, normalizing BA and cholesterol synthesis and circulating PCSK9 levels, indicating that overproduction of cholesterol in enlarged peripheral tissues cannot explain this phenotype. We propose that excessive food intake promotes faecal loss of BAs and cholesterol contributing to their hepatic deficiencies. © 2017 The Authors. Journal of Internal Medicine published by John Wiley & Sons Ltd on behalf of Association for Publication of The Journal of Internal Medicine.

  10. The Impact of Exercise Training Compared to Caloric Restriction on Hepatic and Peripheral Insulin Resistance in Obesity

    Science.gov (United States)

    Coker, Robert H.; Williams, Rick H.; Yeo, Sophie E.; Kortebein, Patrick M.; Bodenner, Don L.; Kern, Philip A.; Evans, William J.

    2009-01-01

    Context: It has been difficult to distinguish the independent effects of caloric restriction versus exercise training on insulin resistance. Objective: Utilizing metabolic feeding and supervised exercise training, we examined the influence of caloric restriction vs. exercise training with and without weight loss on hepatic and peripheral insulin resistance. Design, Participants, and Intervention: Thirty-four obese, older subjects were randomized to: caloric restriction with weight loss (CR), exercise training with weight loss (EWL), exercise training without weight loss (EX), or controls. Based on an equivalent caloric deficit in EWL and CR, we induced matched weight loss. Subjects in the EX group received caloric compensation. Combined with [6,62H2]glucose, an octreotide, glucagon, multistage insulin infusion was performed to determine suppression of glucose production (SGP) and insulin-stimulated glucose disposal (ISGD). Computed tomography scans were performed to assess changes in fat distribution. Results: Body weight decreased similarly in EWL and CR, and did not change in EX and controls. The reduction in visceral fat was significantly greater in EWL (−71 ± 15 cm2) compared to CR and EX. The increase in SGP was also almost 3-fold greater (27 ± 2%) in EWL. EWL and CR promoted similar improvements in ISGD [+2.5 ± 0.4 and 2.4 ± 0.9 mg · kg fat-free mass (FFM)−1 · min−1], respectively. Conclusions: EWL promoted the most significant reduction in visceral fat and the greatest improvement in SGP. Equivalent increases in ISGD were noted in EWL and CR, whereas EX provided a modest improvement. Based on our results, EWL promoted the optimal intervention-based changes in body fat distribution and systemic insulin resistance. PMID:19808853

  11. Low-versus high-glycemic index diets in women: effects on caloric requirement, substrate utilization and insulin sensitivity.

    Science.gov (United States)

    Clapp, James F; Lopez, Beth

    2007-09-01

    Lowering dietary glycemic index appears to have positive health effects in obese and/or insulin resistant individuals. However, detailed studies in lean young men show no effect. This study was designed to test the null hypothesis that a diet rich in low-glycemic carbohydrate has no effect on lipid profile, caloric requirements, fat oxidation, or insulin sensitivity in adult women when compared to one rich in high-glycemic carbohydrate. The metabolic feeding protocol used was conducted in both a free-living and in-patient setting using a randomized crossover design. Seven women were studied on each of 2 diets in which 60% of the calories were from either high- or low-glycemic carbohydrate sources. Each diet lasted 20 days with measurements of caloric requirement, resting metabolic rate, glucose and insulin responses to diet and activity, insulin sensitivity, and lipid profile over the last 7 days. Caloric requirement was determined by bomb calorimetry. Other techniques included indirect calorimetry, hydrodensitometry, stable isotope tracers, and the euglycemic clamp. On the low-glycemic index diet the women's caloric requirements were 11% +/- 1% higher, fat oxidation at fasted rest supplied an average of 45% +/- 4% versus 28% +/- 5% of oxidative requirements, average glucose and insulin levels were approximately 40% lower, low density lipoproteins (LDL) and leptin concentrations were lower, and various indices of insulin sensitivity were > 20% higher. In this group of adult women, a diet that lowered glycemic index well below that typically found in western diets increased both daily caloric requirement and fat oxidation, decreased insulin and glucose concentrations and increased insulin sensitivity.

  12. Gaia transient detection efficiency: hunting for nuclear transients

    CERN Document Server

    Blagorodnova, Nadejda; Harrison, Diana L; Koposov, Sergey; Mattila, Seppo; Campbell, Heather; Walton, Nicholas A; Wyrzykowski, Lukasz

    2015-01-01

    We present a study of the detectability of transient events associated with galaxies for the Gaia European Space Agency astrometric mission. We simulated the on-board detections, and on-ground processing for a mock galaxy catalogue to establish the properties required for the discovery of transient events by Gaia, specifically tidal disruption events (TDEs) and supernovae (SNe). Transients may either be discovered by the on-board detection of a new source or by the brightening of a previously known source. We show that Gaia transients can be identified as new detections on-board for offsets from the host galaxy nucleus of 0.1--0.5,arcsec, depending on magnitude and scanning angle. The Gaia detection system shows no significant loss of SNe at close radial distances to the nucleus. We used the detection efficiencies to predict the number of transients events discovered by Gaia. For a limiting magnitude of 19, we expect around 1300 SNe per year: 65% SN Ia, 28% SN II and 7% SN Ibc, and ~20 TDEs per year.

  13. Efeito dos conservantes sobre a densidade calórica em músculos de Hoplias aff. malabaricus (Bloch, 1794 (Osteichthyes, Erythrinidae Effect of preservatives on caloric density in the muscles of Hoplias aff. malabaricus (Bloch, 1794 (Osteichthyes, Erythrinidae

    Directory of Open Access Journals (Sweden)

    Milena Morimoto

    2002-05-01

    Full Text Available A conservação de amostras para a determinação dos valores calóricos em estudos de bioenergética de peixes tem se apresentado, na literatura, com uma variedade de métodos. Com o intuito de identificar o efeito de conservantes sobre os resultados obtidos com as diferentes técnicas de conservação, foram coletados exemplares adultos de Hoplias aff. malabaricus (Osteichthyes, Erythrinidae na planície de inundação do rio Paraná. De cada exemplar, foram retiradas 5 amostras da musculatura, as quais foram submetidas aos seguintes tratamentos: formol (4%, álcool (70%, congelamento (-10oC, nitrogênio líquido (-180oC e estufa à 60oC (amostra controle. Depois de 30 dias, todas as amostras foram secas em estufa à 60oC e posteriormente procedeu-se à determinação calórica de cada uma das amostras em bomba calorimétrica. Detectaram-se diferenças significativas entre os tratamentos (ANOVA: N=206; F=50,28; pThe preservation of samples for caloric values determination in bioenergetic studies of fish has been presented literature with a variety of methods. To identify the effect of preservatives over the results obtained with different preservation techniques, adult individuals of Hoplias aff. malabaricus (Osteichthyes, Erythrinidae were collected in Paraná river floodplain. From each fish, five samples were extracted from its dorsal muscle and submitted each sample for a different treatment: ice (-10ºC, formaldehyde (4%, alcohol (70%, liquid nitrogen (-180oC and a control sample immediately oven dried (60oC. After 30 days, the treatments were oven dried (60oC and caloric values of each sample were determined in a caloric bomb. Significant differences among the treatments were found (ANOVA: n = 206; F = 50.28; p < 0.001. Some evaluations of the effects of each treatment were presented for further comparisons with the results published in literature.

  14. Study of water flowrate using time transient and cross-correlation techniques with {sup 82}Br radiotracer; Estudo da vazao da agua utilizando as tecnicas de transiente de tempo e cross-correlacao com 82-Bromine como radiotracador

    Energy Technology Data Exchange (ETDEWEB)

    Salgado, William L., E-mail: william.otero@hotmail.com [Instituto Federal do Rio de Janeiro (IFRJ), Rio de Janeiro, RJ (Brazil); Brandao, Luiz E.B., E-mail: brandao@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    This paper aims to determinate the water flowrate using Time Transient and Cross-Correlation techniques. The detection system uses two NaI (T1) detectors adequately positioned on the outside of pipe and a gamma-ray source ({sup 82}Br radiotracer). The water flowrate measurements using Time Transient and Cross-Correlation techniques were compared to invasive conventional measurements of the flowrate previously installed in pipeline. Discrepancies between Time Transient and Cross-Correlation techniques flowmeter previously installed in pipeline. Discrepancies between Time Transient and Cross-Correlation techniques flowrate values were found to be less than 3% in relation to conventional ones. (author)

  15. Recent development of transient electronics

    Directory of Open Access Journals (Sweden)

    Huanyu Cheng

    2016-01-01

    Full Text Available Transient electronics are an emerging class of electronics with the unique characteristic to completely dissolve within a programmed period of time. Since no harmful byproducts are released, these electronics can be used in the human body as a diagnostic tool, for instance, or they can be used as environmentally friendly alternatives to existing electronics which disintegrate when exposed to water. Thus, the most crucial aspect of transient electronics is their ability to disintegrate in a practical manner and a review of the literature on this topic is essential for understanding the current capabilities of transient electronics and areas of future research. In the past, only partial dissolution of transient electronics was possible, however, total dissolution has been achieved with a recent discovery that silicon nanomembrane undergoes hydrolysis. The use of single- and multi-layered structures has also been explored as a way to extend the lifetime of the electronics. Analytical models have been developed to study the dissolution of various functional materials as well as the devices constructed from this set of functional materials and these models prove to be useful in the design of the transient electronics.

  16. Percepción de sed e ingesta de líquido después del ejercicio en el calor

    OpenAIRE

    Aragón-Vargas, Luis Fernando; Capitán Jiménez, Catalina

    2016-01-01

    La sudoración durante el ejercicio en el calor puede producir una deshidratación importante que debe reponerse mediante la ingesta de líquido. Este estudio experimental evalúa la afirmación de que la ingesta voluntaria de agua, que supuestamente ocurre como respuesta a la sed, es suficiente para reponer el líquido perdido. 14 participantes realizaron ejercicio en dos ocasiones en un cuarto de clima controlado programado para calor seco (tbs = 33.8C, HR = 53%) y calor húmedo (tbs = 32.1C y H...

  17. El golpe de calor en la actividad física y el deporte (versión traducida al español)

    OpenAIRE

    Hosokawa, Yuri; Adams, William M.; Stearns, Rebecca L.; Casa, Douglas J

    2014-01-01

    El golpe de calor por esfuerzo (GCE) es una de las causas principales de muerte súbita durante el deporte y la actividad física. Solamente en el fútbol americano han ocurrido 46 muertes documentadas en los EE.UU. entre 1995 y 2010. En el 2003, la asociación responsable por los deportes universitarios de los EE.UU. estableció pautas obligatorias de aclimatización al calor, las cuales tuvieron como resultado una disminución exitosa en el número de muertes por golpe de calor en ese deporte. Sin ...

  18. Percepción de sed e ingesta de líquido después del ejercicio en el calor

    OpenAIRE

    Aragón-Vargas, Luis Fernando; Capitán Jiménez, Catalina

    2016-01-01

    La sudoración durante el ejercicio en el calor puede producir una deshidratación importante que debe reponerse mediante la ingesta de líquido. Este estudio experimental evalúa la afirmación de que la ingesta voluntaria de agua, que supuestamente ocurre como respuesta a la sed, es suficiente para reponer el líquido perdido. 14 participantes realizaron ejercicio en dos ocasiones en un cuarto de clima controlado programado para calor seco (tbs = 33.8C, HR = 53%) y calor húmedo (tbs = 32.1C y H...

  19. El golpe de calor en la actividad física y el deporte (versión traducida al español)

    OpenAIRE

    Hosokawa, Yuri; Adams, William M; Stearns, Rebecca L.; Casa, Douglas J.

    2014-01-01

    El golpe de calor por esfuerzo (GCE) es una de las causas principales de muerte súbita durante el deporte y la actividad física. Solamente en el fútbol americano han ocurrido 46 muertes documentadas en los EE.UU. entre 1995 y 2010. En el 2003, la asociación responsable por los deportes universitarios de los EE.UU. estableció pautas obligatorias de aclimatización al calor, las cuales tuvieron como resultado una disminución exitosa en el número de muertes por golpe de calor en ese deporte. Sin ...

  20. Función de Green para la ecuación hiperbólica de transmisión del calor.

    OpenAIRE

    2008-01-01

    En esta memoria se recoge fundamentalmente el estudio, bajo el punto de vista del modelo hiperbólico de transmisión del calor, de un problema de transmisión del calor basado en el procesado de materiales mediante pulsos de láser de alta intensidad y tiempos de aplicación muy cortos. Este tipo de problemas lleva asociado el desarrollo de un riguroso estudio matemático para la ecuación hiperbólica de transmisión del calor que nos permita establecer los fundamentos teóricos para el cálculo ...

  1. Ablation of TRPM5 in Mice Results in Reduced Body Weight Gain and Improved Glucose Tolerance and Protects from Excessive Consumption of Sweet Palatable Food when Fed High Caloric Diets.

    Directory of Open Access Journals (Sweden)

    Marie H Larsson

    Full Text Available The calcium activated cation channel transient receptor potential channel type M5 (TRPM5 is part of the downstream machinery of the taste receptors and have been shown to play a central role in taste signalling. In addition it is also found in other types of chemosensory cells in various parts of the body as well as in pancreatic β-cells. The aim of this study was to investigate the effects of TRPM5 gene ablation on body weight, insulin sensitivity and other metabolic parameters in long-term high caloric diet induced obesity. Trpm5-/- mice gained significantly less body weight and fat mass on both palatable carbohydrate and fat rich cafeteria diet and 60% high fat diet (HFD and developed less insulin resistance compared to wild type mice. A main finding was the clearly improved glucose tolerance in Trpm5-/- mice compared to wild type mice on cafeteria diet, which was independent of body weight. In addition, it was shown that Trpm5-/- mice consumed the same amount of calories when fed a HFD only or a HFD in combination with a palatable chocolate ball, which is in contrast to wild type mice that increased their caloric intake when fed the combination, mainly due to excessive consumption of the chocolate ball. Thus the palatable sugar containing diet induced overeating was prevented in Trpm5-/- mice. This indicates that sweet taste induced overeating may be a cause for the increased energy intake and glucose intolerance development seen for wild type mice on a sugar and high fat rich cafeteria diet compared to when on a high fat diet. This study point to an important role for the taste signalling system and TRPM5 in diet induced glucose intolerance.

  2. Ablation of TRPM5 in Mice Results in Reduced Body Weight Gain and Improved Glucose Tolerance and Protects from Excessive Consumption of Sweet Palatable Food when Fed High Caloric Diets.

    Science.gov (United States)

    Larsson, Marie H; Håkansson, Pernilla; Jansen, Frank P; Magnell, Kerstin; Brodin, Peter

    2015-01-01

    The calcium activated cation channel transient receptor potential channel type M5 (TRPM5) is part of the downstream machinery of the taste receptors and have been shown to play a central role in taste signalling. In addition it is also found in other types of chemosensory cells in various parts of the body as well as in pancreatic β-cells. The aim of this study was to investigate the effects of TRPM5 gene ablation on body weight, insulin sensitivity and other metabolic parameters in long-term high caloric diet induced obesity. Trpm5-/- mice gained significantly less body weight and fat mass on both palatable carbohydrate and fat rich cafeteria diet and 60% high fat diet (HFD) and developed less insulin resistance compared to wild type mice. A main finding was the clearly improved glucose tolerance in Trpm5-/- mice compared to wild type mice on cafeteria diet, which was independent of body weight. In addition, it was shown that Trpm5-/- mice consumed the same amount of calories when fed a HFD only or a HFD in combination with a palatable chocolate ball, which is in contrast to wild type mice that increased their caloric intake when fed the combination, mainly due to excessive consumption of the chocolate ball. Thus the palatable sugar containing diet induced overeating was prevented in Trpm5-/- mice. This indicates that sweet taste induced overeating may be a cause for the increased energy intake and glucose intolerance development seen for wild type mice on a sugar and high fat rich cafeteria diet compared to when on a high fat diet. This study point to an important role for the taste signalling system and TRPM5 in diet induced glucose intolerance.

  3. Ablation of TRPM5 in Mice Results in Reduced Body Weight Gain and Improved Glucose Tolerance and Protects from Excessive Consumption of Sweet Palatable Food when Fed High Caloric Diets

    Science.gov (United States)

    Larsson, Marie H.; Håkansson, Pernilla; Jansen, Frank P.; Magnell, Kerstin; Brodin, Peter

    2015-01-01

    The calcium activated cation channel transient receptor potential channel type M5 (TRPM5) is part of the downstream machinery of the taste receptors and have been shown to play a central role in taste signalling. In addition it is also found in other types of chemosensory cells in various parts of the body as well as in pancreatic β-cells. The aim of this study was to investigate the effects of TRPM5 gene ablation on body weight, insulin sensitivity and other metabolic parameters in long-term high caloric diet induced obesity. Trpm5-/- mice gained significantly less body weight and fat mass on both palatable carbohydrate and fat rich cafeteria diet and 60% high fat diet (HFD) and developed less insulin resistance compared to wild type mice. A main finding was the clearly improved glucose tolerance in Trpm5-/- mice compared to wild type mice on cafeteria diet, which was independent of body weight. In addition, it was shown that Trpm5-/- mice consumed the same amount of calories when fed a HFD only or a HFD in combination with a palatable chocolate ball, which is in contrast to wild type mice that increased their caloric intake when fed the combination, mainly due to excessive consumption of the chocolate ball. Thus the palatable sugar containing diet induced overeating was prevented in Trpm5-/- mice. This indicates that sweet taste induced overeating may be a cause for the increased energy intake and glucose intolerance development seen for wild type mice on a sugar and high fat rich cafeteria diet compared to when on a high fat diet. This study point to an important role for the taste signalling system and TRPM5 in diet induced glucose intolerance. PMID:26397098

  4. Electromagnetic Transients in Power Cables

    DEFF Research Database (Denmark)

    Silva, Filipe Faria Da; Bak, Claus Leth

    of electromagnetic phenomena associated to their operation, among them electromagnetic transients, increased as well. Transient phenomena have been studied since the beginning of power systems, at first using only analytical approaches, which limited studies to more basic phenomena; but as computational tools became...... concerning HVAC cables. An important topic that is not covered in this book is measurements protocols/ methods. The protocols used when performing measurements on a cable depend on what is to be measured, the available equipment and accessibility. Readers interested in the topic are referred to search....... The chapter ends by proposing a systematic method that can be used when doing the insulation co-ordination study for a line, as well as the modelling requirements, both modelling depth and modelling detail of the equipment, for the study of the different types of transients followed by a step-by-step generic...

  5. Transient Faults in Computer Systems

    Science.gov (United States)

    Masson, Gerald M.

    1993-01-01

    A powerful technique particularly appropriate for the detection of errors caused by transient faults in computer systems was developed. The technique can be implemented in either software or hardware; the research conducted thus far primarily considered software implementations. The error detection technique developed has the distinct advantage of having provably complete coverage of all errors caused by transient faults that affect the output produced by the execution of a program. In other words, the technique does not have to be tuned to a particular error model to enhance error coverage. Also, the correctness of the technique can be formally verified. The technique uses time and software redundancy. The foundation for an effective, low-overhead, software-based certification trail approach to real-time error detection resulting from transient fault phenomena was developed.

  6. Cohabitation Duration and Transient Domesticity.

    Science.gov (United States)

    Golub, Andrew; Reid, Megan; Strickler, Jennifer; Dunlap, Eloise

    2013-01-01

    Research finds that many impoverished urban Black adults engage in a pattern of partnering and family formation involving a succession of short cohabitations yielding children, a paradigm referred to as transient domesticity. Researchers have identified socioeconomic status, cultural adaptations, and urbanicity as explanations for aspects of this pattern. We used longitudinal data from the 2001 Survey of Income and Program Participation to analyze variation in cohabitation and marriage duration by race/ethnicity, income, and urban residence. Proportional hazards regression indicated that separation risk is greater among couples that are cohabiting, below 200% of the federal poverty line, and Black but is not greater among urban dwellers. This provides empirical demographic evidence to support the emerging theory of transient domesticity and suggests that both socioeconomic status and race explain this pattern. We discuss the implications of these findings for understanding transient domesticity and make recommendations for using the Survey of Income and Program Participation to further study this family formation paradigm.

  7. Fluxos de calor no dossel vegetativo e infiltração de água no solo, em floresta tropical Heat fluxes in the vegetative canopy and water infiltration in tropical forest

    Directory of Open Access Journals (Sweden)

    Vanessa de A. Dantas

    2011-12-01

    Full Text Available Este estudo analisou as variações sazonais e anuais dos fluxos de calor sensível e latente, armazenados pelo dossel vegetativo de floresta tropical úmida, bem como a taxa de infiltração de água no solo em duas parcelas experimentais, uma com exclusáo de chuva e outra submetida às condições reais de precipitação pluvial. Os dados aqui usados foram obtidos do projeto ''Estudo da Seca da Floresta (ESECAFLOR, subprojeto do Experimento de Grande Escala da Biosfera-Atmosfera na Amazônia (LBA, conduzido na reserva florestal de terra firme em Caxiuaná, PA. Os dados de temperatura e umidade relativa do ar foram coletados no perfil da floresta amazônica, em intervalos de 8 m, deSd e a superfície até 32 m, durante o ano de 2008, em intervalos horários, para se determinar os fluxos de calor sensível e latente armazenados nos período chuvoso (fevereiro, março e abril e menos chuvoso (setembro, outubro e novembro. Os resultados indicaram que o fluxo de calor sensível armazenado no dossel da floresta no ano de 2008, foi 167,93 W m-2 e o fluxo de calor latente armazenado foi de 5184,38 W m-2. A taxa de infiltração de água do solo na floresta foi reduzida drasticamente nos primeiros minutos do início do experimento, independentemente das condições de umidade do solo e, em seguida, ela apresentou comportamento quase constante ao longo do tempo.This study assessed the seasonal and annual variations in both sensible and latent heat storage fluxes in the canopy air-space of tropical rainforest, as well as the infiltration rate in soil in two experimental plots one with exclusion of rainfall and other under actual rainfall. The data used in this study were obtained during the ''Long-term drought impact on water and carbon dioxide fluxes in Amazonian Tropical Rainforest Experiment'' (ESECAFLOR which is subproject of Large Scale Biosphere Atmosphere Experiment in Amazon forest (LBA, carried out in Caxiuaná National Forest, Pará, Brazil

  8. Transient osteoporosis of the hip.

    Science.gov (United States)

    Mirza, Rabeea; Ishaq, Saliha; Amjad, Hira

    2012-02-01

    Transient Osteoporosis of Hip (TOH) is an uncommon disorder of idiopathic nature, particularly in the Asian population. It has been described to mostly occur in middle aged men and women in their third trimester of pregnancy. A distinctive hallmark of this condition is that it is self limiting and resolves in a few months. The patient presents to the physician with pain on movement and impaired mobility of the affected joint, developing without any history of trauma. MRI is the main diagnostic tool. We report herein a case of a forty five year old male, who developed transient osteoporosis of the hip, and was managed conservatively.

  9. High Caloric Diet for ALS Patients: High Fat, High Carbohydrate or High Protein

    Directory of Open Access Journals (Sweden)

    Sarvin Sanaie

    2015-01-01

    . They showed that patients in the highcarbohydrate/high-calorie groups gained 0.39 kg more weight per month, compared with 0.11kg per month in the control group, and there was an average weight loss of 0.46 kg per month in the high-fat/high-calorie group. However, there are some concerns that highcarbohydrate low-fat diets might increase the risk of ALS and these findings should be interpreted with caution (4. Furthermore, according to Wills et al. high fat-high caloric diets could not be ideal regimens for these patients due to the associated gastrointestinal complications (3. Dorst and associates, in their study, showed that high caloric food supplement with high fat is suitable to establish body weight compared to high carbohydrate formula. Hence, it seems that high protein-high caloric diets could be more appropriate options for both improving negative nitrogen balance and decreasing muscle atrophy in patients with ALS based on the pathophysiology of proteinenergy malnutrition and hypermetabolism which is thought to be due to mitochondria problem. The multifactorial pathophysiology of ALS has resulted in hypotheses that there may be subgroups of patients, eventually defined by a specific underlying etiology or clinical presentation, which selectively respond to a particular regimen. Consequently, further RCTs with larger sample size are required to clarify the best regimen for weight gain and improved survival in ALS patients and it seems that personalized nutritional support or combined regimens might be the best way and could improve the quality of life considering the complex pathophysiology of malnutrition.

  10. Respostas termorregulatórias de crianças no exercício em ambiente de calor Respuestas termorreguladoras de niños en el ejercicio en ambiente de calor Thermoregulatory responses of children exercising in a hot environment

    Directory of Open Access Journals (Sweden)

    Luis Henrique L. S. Gomes

    2013-03-01

    Full Text Available OBJETIVO: Revisar as possíveis peculiaridades nos mecanismos biológicos referentes às respostas termorregulatórias e sudorípara específicas no exercício realizado por crianças em ambiente de calor. FONTES DE DADOS: Foi feita uma revisão de 47 artigos publicados entre 1960 e 2011 nas bases de dados eletrônicos MedLine e SciELO Brasil, com a utilização dos seguintes descritores: 'crianças', 'calor', 'sudorese', 'termorregulação', 'glândula sudorípara' e 'exercício', sendo usados isoladamente ou em combinação, além de uma tese de doutorado sobre o assunto. SÍNTESE DOS DADOS: Em pré-púberes, a taxa de sudorese durante o esforço é menor em comparação aos adultos. Crianças possuem características termorregulatórias diferenciadas, apresentando um débito de suor por glândula muito menor. A maior razão entre área de superfície e massa corporal faz com que crianças absorvam mais calor durante o exercício sob estresse térmico, elevando o risco de apresentarem sintomas de hipertermia. O maior fluxo sanguíneo para a pele contribui com um melhor controle da homeostase térmica de crianças. O menor tamanho da glândula, a menor sensibilidade colinérgica, os níveis baixos de catecolaminas circulantes durante o esforço e a falta de hormônio androgênico explicam a ocorrência da baixa eliminação de suor no exercício realizado por crianças. CONCLUSÕES: Crianças exibem glândulas sudoríparas imaturas. Assim, a prática de atividade física combinada a altas temperaturas não é bem tolerada havendo maior vulnerabilidade às lesões térmicas. No calor, deve-se ter um controle rigoroso da ingestão de líquidos e um monitoramento atencioso das condições climáticas para maior segurança na prática de exercícios.OBJETIVO: Revisar las posibles peculiaridades en los mecanismos biológicos referentes a las respuestas termorreguladoras y sudorípara específicas en el ejercicio realizado por niños en ambiente de

  11. Heat transfer in simple houses; Transferencia de calor en casas habitacion

    Energy Technology Data Exchange (ETDEWEB)

    Porta, Miguel Angel; Rubio, Eduardo; Fernandez, Jose Luis [Centro de Investigaciones Biologicas del Noroeste, Baja California Sur, (Mexico); Gomez Munoz, Victor [Centro Interdiciplinario de Ciencias Marinas, Baja California Sur (Mexico)

    2000-07-01

    A lumped parameter model is used to represent, with a high degree of precision, the temperature and comfort evolution with the time of a simple house, under any hot, extreme weather variation. Results are validated by experimental work in physical models, built to scale 1:2, with materials and building techniques typical of social interest housing in Baja California, Mexico. With the mathematical model properly calibrated, adequately validated heat transfer coefficients between walls, ceiling and windows are calculated. Sensitivity analyses lead to values of heat loads in simple houses with varying shapes, orientation, shading devices, and construction materials and techniques. Energy balance in the present work is achieved by means of three simultaneous equations, each depicting energy equilibrium in one of the basic building elements: the window glazing, the building materials, and inside air. Simultaneous solution of the equations is accomplished with of the Kutta method, which yields the representative temperature along the day of each of the components, while heat flow among them is calculated, together with thermal exchange with the environment. Comfort levels, energy consumption and saving are hence easily derived, and the economical pertinence of passive elements can be evaluated. [Spanish] Este trabajo presenta un modelo matematico de parametros concentrados que representa, de manera apropiada, el comportamiento de una casa habitacion tipica a lo largo de un dia cualquiera. Los resultados se validan mediante la experimentacion en modelo fisico, donde se ensayan casetas de material y dimensiones similares a las casas de interes social, a escala 1:2. Una vez que se ha calibrado el modelo, se pueden determinar, mediante corridas apropiadas en computadora, los coeficientes especificos de transferencia de calor en muros, ventanas y techo. Los analisis subsecuentes de sensibilidad producen informacion util para conocer los requerimientos energeticos de cada casa

  12. Effect of caloric restriction on myenteric neuroplasticity in the rat duodenum during aging.

    Science.gov (United States)

    da Silva Porto, Gisele; Bertaglia Pereira, Joice Naiara; Tibúrcio, Vanessa Graciele; Stabille, Sandra Regina; Garcia de Faria, Haroldo; de Melo Germano, Ricardo; de Britto Mari, Renata

    2012-05-21

    The objective of this study was to evaluate the effects of caloric restriction (CR) on myenteric neurons in the duodenum of Wistar rats during aging. Thirty rats were divided into three groups: the C group (six-month-old animals that were fed a normal diet from weaning until six months of age), the SR group (18-month-old animals that were fed a normal diet from weaning until 18 months of age) and the CR group (18-month-old animals that were fed a 30% CR diet after six months of age). After 12 months, the animals were euthanized. Whole-mount preparations of the duodenums were either stained with Giemsa or underwent NADPH-diaphorase histochemistry to determine the general myenteric neuron population and the nitrergic neuron subpopulation (NADPH-d+), respectively. The NADPH-d-negative (NADPH-d-) neuron population was estimated based on the difference between the Giemsa-stained and NADPH-d+ neurons. The neurons were counted, and the cell body areas were measured. Aging was associated with neuronal loss in the SR group, which was minimized by caloric restriction in the CR group. The density (mm(2)) of the Giemsa-stained neurons was higher in the SR group (79.09 ± 6.25) than in the CR (92.37 ± 11.6) and C (111.68 ± 15.26) groups. The density of the NADPH-d+ neurons was higher in the SR group (44.90 ± 5.88) than in the C (35.75 ± 1.6) and RC (39.14 ± 7.02) groups. The density of NADPH-d- neurons was higher in the CR (49.73 ± 12.08) and C (75.64 ± 17.05) groups than in the SR group (33.82 ± 4.5). In the C group, 32% and 68% of the Giemsa-stained myenteric neurons were NADPH-d+ or NADPH-d-, respectively. With aging (SR group), the percentage of nitrergic neurons (56.77%) increased, whereas the percentage of NADPH-d- neurons (43.22%) decreased. In the CR group, the change in the percentage of nitrergic (42.37%) and NADPH-d- (57.62%) neurons was lower. As NADPH-d- neurons will be mostly cholinergic neurons, CR appears to reduce the loss of cholinergic neurons during

  13. Tolerancia al calor y humedad atmosférica de diferentes grupos raciales de ganado bovino

    Directory of Open Access Journals (Sweden)

    Ariel Guillén T

    2011-04-01

    Full Text Available Objetivo. Comparar algunas respuestas fisiológicas al calor y humedad atmosférica entre bovinos Chinampos (Bos taurus; Ch, ½ Charolais ½ Brahman (CB, Holstein (H y Jersey (J. Materiales y métodos. Se realizó un estudio en La Paz, México. Se utilizaron 12 vacas H, 10 J, 15 Ch y 8 CB. Durante el verano se midieron cada semana (a las 0600 y 1600 horas la frecuencia respiratoria (FR y temperatura rectal (TR. Se registraron las variables climáticas para calcular el índice de temperatura-humedad (ITH. Resultados. Durante todo el verano, la FR en los cuatro grupos estuvo por encima de los valores fisiológicos para el ganado bovino, siendo superior en H y J que en Ch y CB (p<0.01. En todos los grupos, la TR estuvo dentro de los límites fisiológicos de la especie estudiada. El grupo racial más afectado fue H (p<0.05. Cuando las constantes fisiológicas fueron analizadas dentro de cada una de tres categorías de ITH (<72, ≥72<78, y ≥78, las vacas H y J mostraron FR superior a las Ch y CB (p<0.01. La TR aumentó conforme se elevó el ITH siendo más marcado en J y H. El incremento de la FR entre la mañana y la tarde de cada día de medición fue mayor en H y J que en Ch y CB (p<0.05. La TR se incrementó más en H que en Ch (p<0.05. Conclusiones. Los grupos raciales más tolerantes al estrés por calor, determinado con base en FR y TR fueron Ch y CB.

  14. Metabolic and behavioral compensations in response to caloric restriction: implications for the maintenance of weight loss.

    Science.gov (United States)

    Redman, Leanne M; Heilbronn, Leonie K; Martin, Corby K; de Jonge, Lilian; Williamson, Donald A; Delany, James P; Ravussin, Eric

    2009-01-01

    Metabolic and behavioral adaptations to caloric restriction (CR) in free-living conditions have not yet been objectively measured. Forty-eight (36.8+/-1.0 y), overweight (BMI 27.8+/-0.7 kg/m(2)) participants were randomized to four groups for 6-months; energy intake at 100% of energy requirements; CR: 25% calorie restriction; CR+EX: 12.5% CR plus 12.5% increase in energy expenditure by structured exercise; LCD: low calorie diet (890 kcal/d) until 15% weight reduction followed by weight maintenance. Body composition (DXA) and total daily energy expenditure (TDEE) over 14-days by doubly labeled water (DLW) and activity related energy activity (AREE) were measured after 3 (M3) and 6 (M6) months of intervention. Weight changes at M6 were -1.0+/-1.1% (CONTROL), -10.4+/-0.9% (CR), -10.0+/-0.8% (CR+EX) and -13.9+/-0.8% (LCD). At M3, absolute TDEE was significantly reduced in CR (-454+/-76 kcal/d) and LCD (-633+/-66 kcal/d) but not in CR+EX or controls. At M6 the reduction in TDEE remained lower than baseline in CR (-316+/-118 kcal/d) and LCD (-389+/-124 kcal/d) but reached significance only when CR and LCD were combined (-351+/-83 kcal/d). In response to caloric restriction (CR/LCD combined), TDEE adjusted for body composition, was significantly lower by -431+/-51 and -240+/-83 kcal/d at M3 and M6, respectively, indicating a metabolic adaptation. Likewise, physical activity (TDEE adjusted for sleeping metabolic rate) was significantly reduced from baseline at both time points. For control and CR+EX, adjusted TDEE (body composition or sleeping metabolic rate) was not changed at either M3 or M6. For the first time we show that in free-living conditions, CR results in a metabolic adaptation and a behavioral adaptation with decreased physical activity levels. These data also suggest potential mechanisms by which CR causes large inter-individual variability in the rates of weight loss and how exercise may influence weight loss and weight loss maintenance. Clinical

  15. Metabolic and behavioral compensations in response to caloric restriction: implications for the maintenance of weight loss.

    Directory of Open Access Journals (Sweden)

    Leanne M Redman

    Full Text Available BACKGROUND: Metabolic and behavioral adaptations to caloric restriction (CR in free-living conditions have not yet been objectively measured. METHODOLOGY AND PRINCIPAL FINDINGS: Forty-eight (36.8+/-1.0 y, overweight (BMI 27.8+/-0.7 kg/m(2 participants were randomized to four groups for 6-months; CONTROL: energy intake at 100% of energy requirements; CR: 25% calorie restriction; CR+EX: 12.5% CR plus 12.5% increase in energy expenditure by structured exercise; LCD: low calorie diet (890 kcal/d until 15% weight reduction followed by weight maintenance. Body composition (DXA and total daily energy expenditure (TDEE over 14-days by doubly labeled water (DLW and activity related energy activity (AREE were measured after 3 (M3 and 6 (M6 months of intervention. Weight changes at M6 were -1.0+/-1.1% (CONTROL, -10.4+/-0.9% (CR, -10.0+/-0.8% (CR+EX and -13.9+/-0.8% (LCD. At M3, absolute TDEE was significantly reduced in CR (-454+/-76 kcal/d and LCD (-633+/-66 kcal/d but not in CR+EX or controls. At M6 the reduction in TDEE remained lower than baseline in CR (-316+/-118 kcal/d and LCD (-389+/-124 kcal/d but reached significance only when CR and LCD were combined (-351+/-83 kcal/d. In response to caloric restriction (CR/LCD combined, TDEE adjusted for body composition, was significantly lower by -431+/-51 and -240+/-83 kcal/d at M3 and M6, respectively, indicating a metabolic adaptation. Likewise, physical activity (TDEE adjusted for sleeping metabolic rate was significantly reduced from baseline at both time points. For control and CR+EX, adjusted TDEE (body composition or sleeping metabolic rate was not changed at either M3 or M6. CONCLUSIONS: For the first time we show that in free-living conditions, CR results in a metabolic adaptation and a behavioral adaptation with decreased physical activity levels. These data also suggest potential mechanisms by which CR causes large inter-individual variability in the rates of weight loss and how exercise may

  16. Accumulation of long-chain glycosphingolipids during aging is prevented by caloric restriction.

    Directory of Open Access Journals (Sweden)

    María José Hernández-Corbacho

    Full Text Available BACKGROUND: Chronic kidney disease and end-stage renal disease are major causes of morbidity and mortality that are seen far more commonly in the aged population. Interestingly, kidney function declines during aging even in the absence of underlying renal disease. Declining renal function has been associated with age-related cellular damage and dysfunction with reports of increased levels of apoptosis, necrosis, and inflammation in the aged kidney. Bioactive sphingolipids have been shown to regulate these same cellular processes, and have also been suggested to play a role in aging and cellular senescence. METHODOLOGY/PRINCIPAL FINDINGS: We hypothesized that alterations in kidney sphingolipids play a role in the declining kidney function that occurs during aging. To begin to address this, the sphingolipid profile was measured in young (3 mo, middle aged (9 mo and old (17 mo C57BL/6 male mice. Interestingly, while modest changes in ceramides and sphingoid bases were evident in kidneys from older mice, the most dramatic elevations were seen in long-chain hexosylceramides (HexCer and lactosylceramides (LacCer, with C14- and C16-lactosylceramides elevated as much as 8 and 12-fold, respectively. Increases in long-chain LacCers during aging are not exclusive to the kidney, as they also occur in the liver and brain. Importantly, caloric restriction, previously shown to prevent the declining kidney function seen in aging, inhibits accumulation of long-chain HexCer/LacCers and prevents the age-associated elevation of enzymes involved in their synthesis. Additionally, long-chain LacCers are also significantly elevated in human fibroblasts isolated from elderly individuals. CONCLUSION/SIGNIFICANCE: This study demonstrates accumulation of the glycosphingolipids HexCer and LacCer in several different organs in rodents and humans during aging. In addition, data demonstrate that HexCer and LacCer metabolism is regulated by caloric restriction. Taken together

  17. Padrão eletroforético de proteínas resistentes ao calor em sementes de milho Electrophorectic pattern of the heat resistant proteins of corn seeds

    Directory of Open Access Journals (Sweden)

    Solange Carvalho Barrios Roveri José

    2005-02-01

    Full Text Available Na aquisição e manutenção da tolerância à dessecação de sementes, há vários mecanismos envolvidos, entre eles a indução das proteínas resistentes ao calor. O objetivo deste trabalho foi avaliar mudanças no padrão eletroforético das proteínas resistentes ao calor de sementes de milho submetidas a alta temperatura de secagem, associando-as à sua tolerância. Foram utilizadas sementes de linhagens, híbridos simples e híbridos recíprocos colhidas com teor de água de aproximadamente 35% e secadas a 45°C. Sementes das linhagens secadas à sombra foram utilizadas como controle e sua qualidade fisiológica foi avaliada por meio do teste de germinação. As proteínas resistentes ao calor foram extraídas de eixos embrionários das sementes em tampão Tris HCl 0,05 M. Não foi possível determinar uma banda específica da fração das proteínas resistentes ao calor que possa servir como marcador da tolerância à alta temperatura de secagem. Houve estabilidade nos padrões de bandas das proteínas provenientes de sementes submetidas à secagem artificial e natural, mesmo quando foram observadas variações nos valores de germinação. Os padrões eletroforéticos das proteínas resistentes ao calor foram semelhantes entre as sementes híbridas e os respectivos recíprocos.Several mechanisms are involved in the acquisition and maintenance of desiccation tolerance by the seeds. One of these mechanisms is related to the induction of heat resitant proteins. The objective of this work was to evaluate changes in the electophorectic patterns of the heat resistant proteins of corn seeds submitted to high drying temperature associating their expression with drying tolerance. Seeds of breeding lines, simple hybrids and respective reciprocals hybrids were utilized. The seeds were harvested with approximately 35% of water content and dried at 45°C. Seeds of lines dried under shadow were used as control and the physiological quality was

  18. Na,K-pump modulates intercellular communication in vascular wall

    DEFF Research Database (Denmark)

    Matchkov, Vladimir; Nilsson, Holger; Aalkjær, Christian

      Ouabain, a specific inhibitor of the Na,K-pump, has previously been shown to interfere with intercellular communication. Here we test the hypothesis that the communication between vascular smooth muscle cells (SMCs) is regulated through an interaction between the Na,K-pump and the Na,Ca-exchanger....... Immunohistochemical analysis suggested that a ouabain-sensitive α2 isoform of the Na,K-pump involved in this interaction. The experiments suggest that the Na,K-pump may affect gap junction conductivity via localized changes in intracellular calcium concentration through modulation of Na,Ca-exchanger activity....... were used as a model for electrical coupling of SMCs by measuring membrane capacitance (Cm). SMCs were uncoupled (evaluated by inhibition of vasomotion and desynchronization of calcium transients in vascular wall, or by reduction to half of Cm measured in paired A7r5 cells) when the Na,K-pump...

  19. Transient filament stretching rheometer II

    DEFF Research Database (Denmark)

    Kolte, Mette Irene; Rasmussen, Henrik K.; Hassager, Ole

    1997-01-01

    The Lagrangian sspecification is used to simulate the transient stretching filament rheometer. Simulations are performed for dilute PIB-solutions modeled as a four mode Oldroyd-B fluid and a semidilute PIB-solution modeled as a non-linear single integral equation. The simulations are compared...

  20. Stationary and Transient Response Statistics

    DEFF Research Database (Denmark)

    Madsen, Peter Hauge; Krenk, Steen

    1982-01-01

    The covariance functions for the transient response of a linear MDOF-system due to stationary time limited excitation with an arbitrary frequency content are related directly to the covariance functions of the stationary response. For rational spectral density functions closed form expressions...

  1. Dynamic and Transient Infinite Elements

    CERN Document Server

    Zhao, Chongbin

    2009-01-01

    Intends to provide the theory and the application of dynamic and transient infinite elements for simulating the far fields of infinite domains involved in many of scientific and engineering problems, based on the author's own work over the years. This title is suitable for computational geoscientists, geotechnical engineers, and civil engineers.

  2. Audiovisual integration of stimulus transients

    DEFF Research Database (Denmark)

    Andersen, Tobias; Mamassian, Pascal

    2008-01-01

    leaving only unsigned stimulus transients as the basis for audiovisual integration. Facilitation of luminance detection occurred even with varying audiovisual stimulus onset asynchrony and even when the sound lagged behind the luminance change by 75 ms supporting the interpretation that perceptual...

  3. Simulation Model of a Transient

    DEFF Research Database (Denmark)

    Jauch, Clemens; Sørensen, Poul; Bak-Jensen, Birgitte

    2005-01-01

    This paper describes the simulation model of a controller that enables an active-stall wind turbine to ride through transient faults. The simulated wind turbine is connected to a simple model of a power system. Certain fault scenarios are specified and the turbine shall be able to sustain operation...

  4. Fish oil supplementation is beneficial on caloric intake, appetite and mid upper arm muscle circumference in children with leukaemia.

    Science.gov (United States)

    Abu Zaid, Zalina; Shahar, Suzana; Jamal, A Rahman A; Mohd Yusof, Noor Aini

    2012-01-01

    A randomised trial was carried out to determine the effect of supplementation of fish oil among 51 children with leukaemia aged 4 to 12 years on appetite level, caloric intake, body weight and lean body mass. They were randomly allocated into the trial group (TG) and the control group (CG). At baseline, 30.8% of TG subjects and 44.0% of CG subjects were malnourished and 7.7% of subject from TG and 28.0% from CG were classified as stunted. The majority of subjects from TG and CG were in the mild malnutrition category for mid upper arm muscle circumference (MUAMC)-for-age. The TG group showed significant increment in MUAMC (0.13 cm vs -0.09 cm) compared with CG at 8 weeks (pappetite level (0.12±0.33) (pappetite level, caloric intake and MUAMC among children with leukaemia.

  5. Improved magneto-caloric effect of the Gd50Co50 metallic glass by minor Si addition

    Science.gov (United States)

    Tang, B. Z.; Yu, P.; Ding, D.; Wu, C.; Xia, L.

    2017-02-01

    In the present work, we studied the effect of minor Si addition on the magneto-caloric effect (MCE) of the Gd50Co50 metallic glass. The Gd50Co50-xSix (x=2, 5) as-spun ribbons show typical amorphous characteristics in structure and magneto-caloric behaviors. The peak values for the magnetic entropy change (-ΔSmpeak) of the Gd50Co50-xSix (x=0, 2, 5) metallic glasses increase significantly with the addition of Si. The mechanism for the enhanced MCE by minor addition of Si was investigated by revealing the relationship between -ΔSmpeak and the Curie temperature in the Gd-Co-based amorphous ribbons.

  6. Study of electro-caloric effect in Ca and Sn co-doped BaTiO3 ceramics

    Science.gov (United States)

    Upadhyay, Sanjay Kumar; Fatima, Iram; Raghavendra Reddy, V.

    2017-04-01

    The present work deals with the study of structural, ferroelectric, dielectric and electro-caloric effects in lead free ferroelectric polycrystalline Ba1-x Ca x Ti0.95Sn0.05O3 (x  =  2, 5 and 10%) i.e. Ca, Sn co-doped BaTiO3 (BTO). Phase purity of the samples is confirmed from x-ray data by using Rietveld refinement. 119Sn Mössbauer reveals homogenous phase as well as iso-valent substitution of Sn at Ti site. Enhancements in ferroelectric and dielectric properties have been observed. Indirect method which is based on Maxwell equation has been used to determine the electro-caloric (EC) effect in the studied ferroelectric ceramics and maximum EC coefficient is observed for Ba0.95Ca0.05Ti0.95Sn0.05O3.

  7. Better Living through Chemistry: Caloric Restriction (CR) and CR Mimetics Alter Genome Function to Promote Increased Health and Lifespan

    Science.gov (United States)

    Gillespie, Zoe E.; Pickering, Joshua; Eskiw, Christopher H.

    2016-01-01

    Caloric restriction (CR), defined as decreased nutrient intake without causing malnutrition, has been documented to increase both health and lifespan across numerous organisms, including humans. Many drugs and other compounds naturally occurring in our diet (nutraceuticals) have been postulated to act as mimetics of caloric restriction, leading to a wave of research investigating the efficacy of these compounds in preventing age-related diseases and promoting healthier, longer lifespans. Although well studied at the biochemical level, there are still many unanswered questions about how CR and CR mimetics impact genome function and structure. Here we discuss how genome function and structure are influenced by CR and potential CR mimetics, including changes in gene expression profiles and epigenetic modifications and their potential to identify the genetic fountain of youth. PMID:27588026

  8. Simulação Monte Carlo com Repesagem Aplicada ao Calor Específico de Sólidos

    Directory of Open Access Journals (Sweden)

    Silva Roberto da

    2002-01-01

    Full Text Available Apresenta-se uma estimativa numérica para a contribuição das vibrações da rede para o calor específico de um sólido cristalino. O método Monte Carlo é utilizado tanto em sua forma original quanto em sua versão mais moderna, que emprega a técnica da repesagem para extrair mais informações de cada simulação. Mostra-se como obter curvas contínuas para grandezas como a energia e o calor específico em função da temperatura a partir de simulação feita em apenas uma temperatura. Os resultados analíticos são incluídos para facilitar a comparação com os resultados da simulação.

  9. Coeficientes de transferencia de calor experimental para el enfriamiento de licor en intercambiadores de placas//Experimental heat transfer coefficients for the liquor cooling in plate heat exchanger

    National Research Council Canada - National Science Library

    Enrique Torres‐Tamayo; Yoalbys Retirado‐Medianeja; Ever Góngora‐Leyva

    2014-01-01

    ... acumulación de incrustaciones en la superficie de intercambio. El objetivo de la investigación es determinar los coeficientes de transferencia de calor y la influencia de las incrustaciones en la...

  10. Absorption heat pump integrated in an effluent purification system; Bomba de calor por absorcion integrada a un sistema de purificacion de efluentes

    Energy Technology Data Exchange (ETDEWEB)

    Santoyo, Socrates; Siqueiros, Javier; Heard, Christopher; Santoyo, Edgar [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1996-12-31

    The results derived of the integration of an absorption heat pump to an industrial effluents purification system, are presented. The advantages of these heat pumps with respect to heat pumps by mechanical compression of vapor, as well as the advantages in using absorption heat pumps in simple distillation systems, are mentioned. Finally, a description is made of the equipment designed and built, as well as the results obtained in a preliminary test. [Espanol] Se presentan los resultados derivados de la integracion de una bomba de calor por absorcion a un sistema de purificacion de efluentes industriales. Se mencionan las ventajas de este tipo de bombas de calor con respecto a las de calor por compresion mecanica de vapor, asi como las ventajas de usar bombas de calor en sistemas de destilacion simple. Finalmente, se describe el equipo disenado y construido, asi como los resultados obtenidos de una prueba preliminar.

  11. Calores de Solución y Propiedades Termodinámicas Relacionadas: Un método Gráfico General de Cálculo

    OpenAIRE

    Alfredo Gómez O.

    2009-01-01

    Se presenta un método gráfico) de cálculo) con el cual es posible evaluar a partir de datos de calor de solución. diferentes propiedades termodinámicas de interés tales como: calores)res diferenciales de solución del soluto y del solvente. A HD,P 2 V ^ HOIF.I • calor de solución a dilución infinita A tH°; entalpias molares parciales relativas del soluto y del solvente. Lj y L,. y la entalpia molar aparente relativa, L^. El método está basado en la representación gráfica del calor integral de...

  12. Effect of replacing sugar with non-caloric sweeteners in beverages on the reward value after repeated exposure.

    Directory of Open Access Journals (Sweden)

    Sanne Griffioen-Roose

    Full Text Available BACKGROUND: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. OBJECTIVE: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty drink (soft drink versus nutrient-rich drink (yoghurt drink on reward value after repeated exposure. DESIGN: We used a randomized crossover design whereby forty subjects (15 men, 25 women with a mean ± SD age of 21 ± 2 y and BMI of 21.5 ± 1.7 kg/m(2 consumed a fixed portion of a non-caloric sweetened (NS and sugar sweetened (SS versions of either a soft drink or a yoghurt drink (counterbalanced for breakfast which were distinguishable by means of colored labels. Each version of a drink was offered 10 times in semi-random order. Before and after conditioning the reward value of the drinks was assessed using behavioral tasks on wanting, liking, and expected satiety. In a subgroup (n=18 fMRI was performed to assess brain reward responses to the drinks. RESULTS: Outcomes of both the behavioral tasks and fMRI showed that conditioning did not affect the reward value of the NS and SS versions of the drinks significantly. Overall, subjects preferred the yoghurt drinks to the soft drinks and the ss drinks to the NS drinks. In addition, they expected the yoghurt drinks to be more satiating, they reduced hunger more, and delayed the first eating episode more. Conditioning did not influence these effects. CONCLUSION: Our study showed that repeated consumption of a non-caloric sweetened beverage, instead of a sugar sweetened version, appears not to result in changes in the reward value. It cannot be ruled out that learned associations between sensory attributes and food satiating capacity which developed preceding the conditioning period, during lifetime, affected the reward value of the drinks.

  13. The effect of brand and caloric information on flavor perception and food consumption in restrained and unrestrained eaters.

    Science.gov (United States)

    Cavanagh, Kevin V; Kruja, Blina; Forestell, Catherine A

    2014-11-01

    The goal of the current study was to determine whether provision of brand and caloric information affects sensory perception and consumption of a food in restrained (n=84) and unrestrained eaters (n=104). Using a between-subjects 2 × 2 × 3 design, female restrained and unrestrained eaters were asked to taste and rate a cookie that was labeled with a brand associated with healthful eating (Kashi(®)) or one associated with unhealthful eating (Nabisco(®)). Additionally, some participants were presented with a nutrition label alongside the brand name indicating that one serving contained 130 calories (Low-Calorie Condition), or 260 calories (High-Calorie Condition). The remaining participants were not shown a nutrition label (No Label Condition). Results indicated that those in the No Label or the High-Calorie Condition perceived the healthful branded cookie to have a better flavor than those who received the unhealthful branded cookie regardless of their restraint status. However, restrained eaters in the No Label Condition consumed more of the healthful than the unhealthful branded cookie, whereas those in the Low-Calorie Condition consumed more of the unhealthful than the healthful branded cookie. In contrast, unrestrained eaters ate more of the healthful branded cookie regardless of the caloric information provided. Thus, although restrained and unrestrained eaters' perceptions are similarly affected by branding and caloric information, brands and caloric information interact to affect restrained eaters' consumption. This study reveals that labeling foods as low calorie may create a halo effect which may lead to over-consumption of these foods in restrained eaters. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Effects of age and caloric restriction in the vascular response of renal arteries to endothelin-1 in rats.

    Science.gov (United States)

    Amor, Sara; García-Villalón, Angel Luis; Rubio, Carmen; Carrascosa, Jose Ma; Monge, Luis; Fernández, Nuria; Martín-Carro, Beatriz; Granado, Miriam

    2017-02-01

    Cardiovascular alterations are the most prevalent cause of impaired physiological function in aged individuals with kidney being one the most affected organs. Aging-induced alterations in renal circulation are associated with a decrease in endothelium-derived relaxing factors such as nitric oxide (NO) and with an increase in contracting factors such as endothelin-1(ET-1). As caloric restriction (CR) exerts beneficial effects preventing some of the aging-induced alterations in cardiovascular system, the aim of this study was to analyze the effects of age and caloric restriction in the vascular response of renal arteries to ET-1 in aged rats. Vascular function was studied in renal arteries from 3-month-old Wistar rats fed ad libitum (3m) and in renal arteries from 8-and 24-month-old Wistar rats fed ad libitum (8m and 24m), or subjected to 20% caloric restriction during their three last months of life (8m-CR and 24m-CR). The contractile response to ET-1 was increased in renal arteries from 8m and 24m compared to 3m rats. ET-1-induced contraction was mediated by ET-A receptors in all experimental groups and also by ET-B receptors in 24m rats. Caloric restriction attenuated the increased contraction to ET-1 in renal arteries from 8m but not from 24m rats possibly through NO release proceeding from ET-B endothelial receptors. In 24m rats, CR did not attenuate the aging-increased response of renal arteries to ET-1, but it prevented the aging-induced increase in iNOS mRNA levels and the aging-induced decrease in eNOS mRNA levels in arterial tissue. In conclusion, aging is associated with an increased response to ET-1 in renal arteries that is prevented by CR in 8m but not in 24m rats.

  15. Effects of fructose-containing caloric sweeteners on resting energy expenditure and energy efficiency: a review of human trials

    OpenAIRE

    Tappy, L; L. Egli; Lecoultre, V.; Schneider, P.

    2013-01-01

    Epidemiological studies indicate that the consumption of fructose-containing caloric sweeteners (FCCS: mainly sucrose and high-fructose corn syrup) is associated with obesity. The hypothesis that FCCS plays a causal role in the development of obesity however implies that they would impair energy balance to a larger extent than other nutrients, either by increasing food intake, or by decreasing energy expenditure. We therefore reviewed the literature comparing a) diet-induced thermogenesis (DI...

  16. Higher Caloric Refeeding Is Safe in Hospitalised Adolescent Patients with Restrictive Eating Disorders

    Science.gov (United States)

    Parker, Elizabeth K.; Faruquie, Sahrish S.; Anderson, Gail; Gomes, Linette; Kennedy, Andrew; Wearne, Christine M.; Kohn, Michael R.; Clarke, Simon D.

    2016-01-01

    Introduction. This study examines weight gain and assesses complications associated with refeeding hospitalised adolescents with restrictive eating disorders (EDs) prescribed initial calories above current recommendations. Methods. Patients admitted to an adolescent ED structured “rapid refeeding” program for >48 hours and receiving ≥2400 kcal/day were included in a 3-year retrospective chart review. Results. The mean (SD) age of the 162 adolescents was 16.7 years (0.9), admission % median BMI was 80.1% (10.2), and discharge % median BMI was 93.1% (7.0). The mean (SD) starting caloric intake was 2611.7 kcal/day (261.5) equating to 58.4 kcal/kg (10.2). Most patients (92.6%) were treated with nasogastric tube feeding. The mean (SD) length of stay was 3.6 weeks (1.9), and average weekly weight gain was 2.1 kg (0.8). No patients developed cardiac signs of RFS or delirium; complications included 4% peripheral oedema, 1% hypophosphatemia (refeeding syndrome. PMID:27293884

  17. Practical system for the direct measurement of magneto-caloric effect by micro-thermocouples.

    Science.gov (United States)

    Kamarád, J; Kaštil, J; Arnold, Z

    2012-08-01

    A system for direct measurements of the magneto-caloric effect (MCE) exploits a rapid transport of a sample into or from magnetic field in permanent Halbach-type (1 T) or superconducting (4.7 T) magnets. Time dependence of induced changes of the sample temperature, ΔT(t), is detected directly by the differential Cu-Constantan-Cu micro-thermocouples with time steps of 300 ms. A sample placed inside an evacuated simple LN(2) cryostat is either totally isolated (adiabatic conditions) or partly connected with the copper sample holder (non-adiabatic conditions). The last arrangement (a model of the Brayton cycle) is used to simulate an application of MCE in refrigeration techniques. The relations describing ΔT(t) that allow an analysis of MCE of the studied materials are based on the general cooling law. The effect of the first-order magnetic transition on MCE of selected sample is also demonstrated by non-standard ΔT(t) curves measured in the last mentioned experimental arrangements.

  18. The effects of caloric stimulation of the labyrinth on the soleus motor pool in man.

    Science.gov (United States)

    Delwaide, P J; Juprelle, M

    1977-04-01

    The effects of caloric stimulation of the labyrinth on the soleus motor pool have been investigated using the Achilles tendon reflex, the H reflex, and the vibratory inhibition of the H reflex. The excitability of the myotatic reflex are is augmented from the beginning of irrigation and remains so until the end of nystagmus. The effects are bilateral and roughly symmetrical. The observed effects are due to simultaneous activation of non-specific, probably reticular, and specific, doubtless vestibular, , mechanisms. The Achilles tendon reflex is more facilitated than the H reflex, and the vibratory inhibition of the H reflex is not modified following irrigation of the ear canal. These results indicate a simultaneous facilitation of alpha and gamma extensor motoneurones but gamma effects clearly predominate. This interpretation is in good agreement with the findings of the animal neurophysiology. The vibratory inhibition argues against a modification of presynaptic inhibition. Before interpreting this fact as different from animal mechanisms, one must take into account the particular experimental conditions realized in man: the stimulus is complex and interactions between various nervous structures are possible.

  19. Entropy Generation and Human Aging: Lifespan Entropy and Effect of Diet Composition and Caloric Restriction Diets

    Directory of Open Access Journals (Sweden)

    Carlos A. Silva

    2009-01-01

    Full Text Available The first and second laws of thermodynamic were applied to statistical databases on nutrition and human growth in order to estimate the entropy generation over the human lifespan. The calculations were performed for the cases of variation in the diet composition and calorie restriction diets; and results were compared to a base case in which lifespan entropy generation was found to be 11 404 kJ/K per kg of body mass, predicting a lifespan of 73.78 and 81.61 years for the average male and female individuals respectively. From the analysis of the results, it was found that changes of diet % of fat and carbohydrates do not have a significant impact on predicted lifespan, while the diet % of proteins has an important effect. Reduction of diet protein % to the minimum recommended in nutrition literature yields an average increase of 3.3 years on the predicted lifespan. Changes in the calorie content of the diet also have an important effect, yielding a % increase in lifespan equal or higher than the % reduction in the diet caloric content. This correlates well experimental data on small mammal and insects, in which lifespan has been increased by diet restriction.

  20. Maintenance of cellular ATP level by caloric restriction correlates chronological survival of budding yeast

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Joon-Seok; Lee, Cheol-Koo, E-mail: cklee2005@korea.ac.kr

    2013-09-13

    Highlights: •CR decreases total ROS and mitochondrial superoxide during the chronological aging. •CR does not affect the levels of oxidative damage on protein and DNA. •CR contributes extension of chronological lifespan by maintenance of ATP level -- Abstract: The free radical theory of aging emphasizes cumulative oxidative damage in the genome and intracellular proteins due to reactive oxygen species (ROS), which is a major cause for aging. Caloric restriction (CR) has been known as a representative treatment that prevents aging; however, its mechanism of action remains elusive. Here, we show that CR extends the chronological lifespan (CLS) of budding yeast by maintaining cellular energy levels. CR reduced the generation of total ROS and mitochondrial superoxide; however, CR did not reduce the oxidative damage in proteins and DNA. Subsequently, calorie-restricted yeast had higher mitochondrial membrane potential (MMP), and it sustained consistent ATP levels during the process of chronological aging. Our results suggest that CR extends the survival of the chronologically aged cells by improving the efficiency of energy metabolism for the maintenance of the ATP level rather than reducing the global oxidative damage of proteins and DNA.

  1. Calor: Una Propuesta Didáctica Constructivista con Enfoque de Ciencia Integrada

    Directory of Open Access Journals (Sweden)

    Castillo Alberto de L.

    2002-01-01

    Full Text Available Realizamos un estudio comparativo entre dos diseños didácticos constructivistas para la enseñanza del tema Calor en estudiantes de carreras en ciencias naturales. Uno con un enfoque de ciencia integrada y el otro con un enfoque no integrador. En el primer diseño el alumno construye su propio conocimiento resolviendo situaciones problemáticas relacionadas a la biología y el medio-ambiente, que le permite analizar y relacionar los conceptos involucrados, mientras que en el segundo construye su conocimiento a través de la resolución de situaciones problemáicas físicas pero no biológicas. Concluimos que el primer diseño favorece en los alumnos la construcción de una estructura cognitiva del tipo integrada, que les facilita internalizar y transferir los conceptos físicos a problemas concretos de su especialidad.

  2. Transport of heat in caloric vestibular stimulation. Conduction, convection or radiation?

    Science.gov (United States)

    Feldmann, H; Hüttenbrink, K B; Delank, K W

    1991-01-01

    Experiments in temporal bone specimens were carried out under strictly controlled conditions: temperature (37 degrees C) and humidity kept constant; standardized irrigation of the external ear canal by an automated system (in 15 s, 50 ml of water, 11 degrees C above temperature of specimen), thermistor probes of 0.2 mm diameter placed in different parts of the specimens. In the intact temporal bone such an irrigation causes a rise in temperature with a gradient from the external ear canal across the bony bridge to the lateral semicircular canal as expected with heat conduction. After removal of the bony bridge, which is the main route for heat conduction, the rise in temperature in the lateral semicircular canal is greater and faster than in the intact specimen. This effect again is drastically reduced by placing a reflecting shield between tympanic membrane and labyrinth. In the intact middle ear inserting a reflecting shield or filling the cavity with gel also reduces the heat transfer to the labyrinth, although the bony routes for heat conduction are left untouched. The experiments prove that radiation plays an important part in heat transfer in caloric stimulation.

  3. Transferencia de calor en la colada continua de aceros. II parte. Enfriamiento secundario

    Directory of Open Access Journals (Sweden)

    Cicutti, C.

    1997-12-01

    Full Text Available Once the strand leaves the mold, the solidification of steel progresses due to the heat extracted in the secondary cooling zone of the continuous casting machine. In this zone, heat is extracted mainly by: the incidence of water from sprays, radiation to surroundings contact with rolls and run out water accumulated between rolls and strand. In this work, all these mechanisms are evaluated and, when it is possible, they are quantified. Methods which are usually employed to measure solidification profiles in the continuous casting machine are also reviewed. Finally, the incidence of secondary cooling on the quality of cast products is discussed.

    La solidificación del acero iniciada en el molde continúa en la zona de enfriamiento secundario de la máquina donde el calor es extraído, principalmente por la incidencia del agua de los rociadores, la radiación al medio ambiente, el contacto con los rodillos y el agua acumulada en ellos. En este trabajo se revisa cada uno de estos mecanismos determinando, en los casos en que es posible, valores cuantitativos de los mismos. Además, se analizan los distintos métodos empleados para medir el avance del espesor solidificado en la máquina de colada continua. Por último, se discute la incidencia del enfriamiento secundario en la calidad final de los productos colados.

  4. [Caloric restriction in primates: how efficient as an anti-aging approach?].

    Science.gov (United States)

    Marchal, Julia; Perret, Martine; Aujard, Fabienne

    2012-12-01

    Caloric restriction (CR) is the only non-genetic intervention known to date to slow the onset of age-related diseases and increase average and maximum lifespan in several species. Its interest is continually growing, particularly for the identification of mechanisms involved in increasing longevity. Unlike studies in invertebrate and rodent models have provided some indication about the mechanisms of the CR, the efficacy of CR as an anti-aging protocol in primates has not yet been fully established. In this review we present the advantages of using non human primates as relevant models to the study of human aging in general and specifically in the context of therapeutic interventions applicable to humans, such as CR. Through the longitudinal findings in the Grey Mouse Lemur (Microcebus murinus), we stress the importance of primate studies in the context of research on aging and their potential to advance the development of molecules which can mimic the beneficial effects of CR, already observed in some species, without imposing a reduced calorie diet.

  5. Evaluation of dysphagia risk, nutritional status and caloric intake in elderly patients with Alzheimer's

    Science.gov (United States)

    Goes, Vanessa Fernanda; Mello-Carpes, Pâmela Billig; de Oliveira, Lilian Oliveira; Hack, Jaqueline; Magro, Marcela; Bonini, Juliana Sartori

    2014-01-01

    Objective to evaluate the risk of dysphagia and its relationship with the stage of Alzheimer's Disease, as well as the relationship between the risk of dysphagia and nutritional status and caloric intake in elderly people with Alzheimer's disease. Methods the sample consisted of 30 subjects of both genders with probable Alzheimer's disease. The stage of the disease, nutritional status, energy intake, and risk of dysphagia were assessed. Results it was found that increased risk of dysphagia is associated with the advance in the stages of Alzheimer's disease and that even patients in the early stages of disease have a slight risk of developing dysphagia. No association was found between nutritional status and the risk of dysphagia. High levels of inadequate intake of micronutrients were also verified in the patients. Conclusion an association between dysphagia and the development of Alzheimer's disease was found. The results indicate the need to monitor the presence of dysphagia and the micronutrient intake in patients with Alzheimer's disease. PMID:26107841

  6. Artigos esterilizados em calor úmido: validação do sistema de guarda

    Directory of Open Access Journals (Sweden)

    Zilah Cândida Pereira das Neves

    2004-04-01

    Full Text Available Objetivamos identificar o tempo de validade da esterilização dos artigos processados pelo calor úmido, considerando as condições de esterilização e guarda. A validação deu-se através de testes microbiológicos realizados com instrumentais processados numa mesma carga e avaliados em tempos 0, 7, 10, 15 e 25 dias. Foram analisados 30% do instrumental de cada pacote que foi colocado em caldo Mueller Hinton e incubado a 37ºC por 72 horas. A leitura deu-se pela turvação do caldo. Das amostras avaliadas de nove cargas, em nenhuma houve crescimento microbiológico. Concluiu-se que apesar das condições de esterilização e guarda do material não se adequarem totalmente dentro dos parâmetros recomendados pela literatura, a esterilização ocorreu e manteve-se por um período de 25 dias.

  7. Severe caloric restriction in young women during World War II and subsequent breast cancer risk.

    Science.gov (United States)

    Vin-Raviv, N; Barchana, M; Linn, S; Keinan-Boker, L

    2012-10-01

    The objective of the study was to examine the impact of WWII-related caloric restriction (CR) on subsequent breast cancer (BC) risk based on individual exposure experiences and whether this effect was modified by age at exposure. We compared 65 breast cancer patients diagnosed between 2005-2010 to 200 controls without breast cancer who were all members of various organizations for Jewish WWII survivors in Israel. All participants were Jewish women born in Europe prior to 1945 who lived at least 6 months under Nazi rule during WWII and immigrated to Israel after the war. We estimated CR using a combined index for hunger and used logistic regression models to estimate the association between CR and BC, adjusting for potential confounders. Women who were severely exposed to hunger had an increased risk of BC (OR=5.0, 95% CI= 2.3-10.8) compared to women who were mildly exposed. The association between CR and BC risk was stronger for women who were exposed at a younger age (0-7 years) compared to the risk of BC in women exposed at ≥ 14 years (OR= 2.8, 95% CI=1.3-6.3). Severe exposure to CR is associated with a higher risk for BC decades later, and may be generalized to other cases of severe starvation during childhood that may have long-term effects on cancer in adulthood. © 2012 Blackwell Publishing Ltd.

  8. Watching a food-related television show and caloric intake. A laboratory study.

    Science.gov (United States)

    Bodenlos, Jamie S; Wormuth, Bernadette M

    2013-02-01

    Television watching has been positively associated with overeating and obesity. How popular food-related television shows affects eating behavior has not been examined. An experimental study was conducted to examine how exposure to a food-related television program affects amount and type of food consumed in adults (N=80). Participants were randomized to watch a cooking or nature television program and were then presented with 800 total calories of chocolate covered candies, cheese curls, and carrots. Food was weighed before and after the ad libitum eating session to determine amount consumed. After controlling for dietary restraint, hunger and food preference, significantly more chocolate covered candies were consumed among individuals who watched the cooking program compared to the nature program. No significant differences between conditions were found for overall caloric intake or for cheese curl or carrot consumption. Findings suggest that watching food-related television programs may affect eating behavior and has implications for obesity prevention and intervention efforts. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Caloric restriction and intermittent fasting: two potential diets for successful brain aging.

    Science.gov (United States)

    Martin, Bronwen; Mattson, Mark P; Maudsley, Stuart

    2006-08-01

    The vulnerability of the nervous system to advancing age is all too often manifest in neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In this review article we describe evidence suggesting that two dietary interventions, caloric restriction (CR) and intermittent fasting (IF), can prolong the health-span of the nervous system by impinging upon fundamental metabolic and cellular signaling pathways that regulate life-span. CR and IF affect energy and oxygen radical metabolism, and cellular stress response systems, in ways that protect neurons against genetic and environmental factors to which they would otherwise succumb during aging. There are multiple interactive pathways and molecular mechanisms by which CR and IF benefit neurons including those involving insulin-like signaling, FoxO transcription factors, sirtuins and peroxisome proliferator-activated receptors. These pathways stimulate the production of protein chaperones, neurotrophic factors and antioxidant enzymes, all of which help cells cope with stress and resist disease. A better understanding of the impact of CR and IF on the aging nervous system will likely lead to novel approaches for preventing and treating neurodegenerative disorders.

  10. Caloric restriction increases ketone bodies metabolism and preserves blood flow in aging brain.

    Science.gov (United States)

    Lin, Ai-Ling; Zhang, Wei; Gao, Xiaoli; Watts, Lora

    2015-07-01

    Caloric restriction (CR) has been shown to increase the life span and health span of a broad range of species. However, CR effects on in vivo brain functions are far from explored. In this study, we used multimetric neuroimaging methods to characterize the CR-induced changes of brain metabolic and vascular functions in aging rats. We found that old rats (24 months of age) with CR diet had reduced glucose uptake and lactate concentration, but increased ketone bodies level, compared with the age-matched and young (5 months of age) controls. The shifted metabolism was associated with preserved vascular function: old CR rats also had maintained cerebral blood flow relative to the age-matched controls. When investigating the metabolites in mitochondrial tricarboxylic acid cycle, we found that citrate and α-ketoglutarate were preserved in the old CR rats. We suggest that CR is neuroprotective; ketone bodies, cerebral blood flow, and α-ketoglutarate may play important roles in preserving brain physiology in aging.

  11. Historical evolution of slope instability in the Calore River Basin, Southern Italy

    Science.gov (United States)

    Diodato, Nazzareno; Soriano, Marcella; Bellocchi, Gianni; Fiorillo, Francesco; Cevasco, Andrea; Revellino, Paola; Guadagno, Francesco Maria

    2017-04-01

    There is interest in knowing historical spatio-temporal patterns of landslide activity. However, this is challenging to reconstruct because it is difficult to obtain detailed records for past landslide activity. Here, we deal with hydro-geomorphological signatures, such as storms, downpours, floods, snowmelt and mass movement, to detect annual slope instability events (ASIEs) over historical times. In order to obtain ASIEs for each year, a monthly Instability Density Index (IDI) was used and then monthly values were summed up to obtain a yearly value. Classes of monthly IDI varying between 0 (no instability) and 4 (highest instability) were determined from historical documents. We present an application for the Calore River Basin, Southern Italy, using data from a 313-year long series (1701-2013 CE). After 1880 CE the information becomes more valuable with directly observed landslide frequency. By this cataloguing, 129 ASIEs were obtained. Their evolution shows slight instability during the 18th century. Uneven and greater slope instability occurred instead across the 19th century, when an important phase of deforestation coincided with intensification of agricultural activities. Slope instability events continued during the 20th century but their causes are mainly related to anthropisation and the effects of recent climate change. It was determined that stormy autumns until the 19th century and successive winter-times with enhanced snowmelt, may have driven the reactivation of widespread instability events. We also found that mountainous and hilly terrains have an acute sensitivity to climate change.

  12. Measuring aging rates of mice subjected to caloric restriction and genetic disruption of growth hormone signaling

    Science.gov (United States)

    Koopman, Jacob J.E.; van Heemst, Diana; van Bodegom, David; Bonkowski, Michael S.; Sun, Liou Y.; Bartke, Andrzej

    2016-01-01

    Caloric restriction and genetic disruption of growth hormone signaling have been shown to counteract aging in mice. The effects of these interventions on aging are examined through age-dependent survival or through the increase in age-dependent mortality rates on a logarithmic scale fitted to the Gompertz model. However, these methods have limitations that impede a fully comprehensive disclosure of these effects. Here we examine the effects of these interventions on murine aging through the increase in age-dependent mortality rates on a linear scale without fitting them to a model like the Gompertz model. Whereas these interventions negligibly and non-consistently affected the aging rates when examined through the age-dependent mortality rates on a logarithmic scale, they caused the aging rates to increase at higher ages and to higher levels when examined through the age-dependent mortality rates on a linear scale. These results add to the debate whether these interventions postpone or slow aging and to the understanding of the mechanisms by which they affect aging. Since different methods yield different results, it is worthwhile to compare their results in future research to obtain further insights into the effects of dietary, genetic, and other interventions on the aging of mice and other species. PMID:26959761

  13. Efficient gasification of wet biomass residue to produce middle caloric gas

    Institute of Scientific and Technical Information of China (English)

    Guangwen Xu; Takahiro Murakami; Toshiyuki Suda; Hidehisa Tani; Yutaka Mito

    2008-01-01

    Various process residues represent a kind of biomass resource already concentrated but containing water as much as 60 wt.%.These materials are generally treated as waste or simply combusted directly to generate heat.Recently,we attempted to convert them into middle caloric gas to substitute for natural gas,as a chemical or a high-rank gaseous fuel for advanced combustion utilities.Such conversion is implemented through dual fluidized bed gasification (DFBG).Concerning the high water content of the fuels,DFBG was suggested to accomplish either with high-efficiency fuel drying in advance or direct decoupling of fuel drying/pyrolysis from char gasification and tar/hydrocarbon reforming.Along with fuel drying,calcium-based catalyst can be impregnated into the fuel,without much additional cost,to increase the fuel's gasification reactivity and to reduce tar formation.This article reports the Ca impregnation method and its resulting effects on gasification reactivity and tar suppression ability.Meanwhile,the principle of directly gasifying wet fuel with decoupled dual fluidized bed gasification (D-DFBG) is also highlighted.

  14. Caloric restriction reveals a metabolomic and lipidomic signature in liver of male mice.

    Science.gov (United States)

    Jové, Mariona; Naudí, Alba; Ramírez-Núñez, Omar; Portero-Otín, Manuel; Selman, Colin; Withers, Dominic J; Pamplona, Reinald

    2014-10-01

    Lipid composition, particularly membrane unsaturation, has been proposed as being a lifespan determinant, but it is currently unknown whether caloric restriction (CR), an accepted life-extending intervention, affects cellular lipid profiles. In this study, we employ a liquid chromatography quadrupole time-of-flight-based methodology to demonstrate that CR in the liver of male C57BL/6 mice: (i) induces marked changes in the cellular lipidome, (ii) specifically reduces levels of a phospholipid peroxidation product, 1-palmitoyl-2-glutaryl-sn-glycero-3-phosphatidylcholine, (iii) alters cellular phosphoethanolamine and triglyceride distributional profiles, (iv) affects mitochondrial electron transport chain complexes, increasing complex II and decreasing complex III and (v) is associated with specific changes in liver metabolic pathways. These data demonstrate that CR induces a specific lipidome and metabolome reprogramming event in mouse liver which is associated with lower protein oxidative damage, as assessed by mass spectrometry-based measurements. Such changes may be critical to the increased lifespan and healthspan observed in C57BL/6 mice following CR.

  15. Caloric Restriction, CR Mimetics, and Healthy Aging in Okinawa: Controversies and Clinical Implications

    Science.gov (United States)

    Willcox, Bradley J.; Willcox, Donald Craig

    2014-01-01

    Purpose of Review To examine the role of two nutritional factors implicated in the healthy aging of the Okinawans: caloric restriction (CR); and traditional foods with potential CR-mimetic properties. Recent Findings CR is a research priority for the U.S. National Institute on Aging. However, little is known regarding health effects in humans. Some CR-related outcomes, such as cause-specific mortality and lifespan, are not practical for human clinical trials. Therefore, epidemiological data on older Okinawans, who experienced a CR-like diet for close to half their lives, are of special interest. The nutritional data support mild CR (10–15%) and high consumption of foods that may mimic the biological effects of CR, including sweet potatoes, marine-based carotenoid-rich foods, and turmeric. Phenotypic evidence is consistent with CR (including short stature, low body weight, lean BMI), less age-related chronic disease (including cardiovascular diseases, cancer, and dementia) and longer lifespan (mean and maximum). Summary Both CR and traditional Okinawan functional foods with CR-mimetic properties likely had roles in the extended healthspan and lifespan of the Okinawans. More research is needed on health consequences of CR and foods with CR-mimetic properties to identify possible nutritional interventions for healthy aging. PMID:24316687

  16. Whole-transcriptome analysis of mouse adipose tissue in response to short-term caloric restriction.

    Science.gov (United States)

    Kim, Seung-Soo; Choi, Kyung-Mi; Kim, Soyoung; Park, Taesun; Cho, In-Cheol; Lee, Jae-Won; Lee, Cheol-Koo

    2016-04-01

    Caloric restriction (CR) has been shown to extend the lifespan of many species by improving cellular function and organismal health. Additionally, fat reduction by CR may play an important role in lengthening lifespan and preventing severe age-related diseases. Interestingly, CR induced the greatest transcriptome change in the epididymal fat of mice in our study. In this transcriptome analysis, we identified and categorized 446 genes that correlated with CR level. We observed down-regulation of several signaling pathways, including insulin/insulin-like growth factor 1 (insulin/IGF-1), epidermal growth factor (EGF), transforming growth factor beta (TGF-β), and canonical wingless-type mouse mammary tumor virus integration site (Wnt). Many genes related to structural features, including extracellular matrix structure, cell adhesion, and the cytoskeleton, were down-regulated, with a strong correlation to the degree of CR. Furthermore, genes related to the cell cycle and adipogenesis were down-regulated. These biological processes are well-identified targets of insulin/IGF-1, EGF, TGF-β, and Wnt signaling. In contrast, genes involved in specific metabolic processes, including the tricarboxylic acid cycle and the electron transport chain were up-regulated. We performed in silico analysis of the promoter sequences of CR-responsive genes and identified two associated transcription factors, Paired-like homeodomain 2 (Pitx2) and Paired box gene 6 (Pax6). Our results suggest that strict regulation of signaling pathways is critical for creating the optimal energy homeostasis to extend lifespan.

  17. Effects of Low-Dose Non-Caloric Sweetener Consumption on Gut Microbiota in Mice

    Directory of Open Access Journals (Sweden)

    Takashi Uebanso

    2017-06-01

    Full Text Available Abstract: Non-caloric artificial sweeteners (NASs provide sweet tastes to food without adding calories or glucose. NASs can be used as alternative sweeteners for controlling blood glucose levels and weight gain. Although the consumption of NASs has increased over the past decade in Japan and other countries, whether these sweeteners affect the composition of the gut microbiome is unclear. In the present study, we examined the effects of sucralose or acesulfame-K ingestion (at most the maximum acceptable daily intake (ADI levels, 15 mg/kg body weight on the gut microbiome in mice. Consumption of sucralose, but not acesulfame-K, for 8 weeks reduced the relative amount of Clostridium cluster XIVa in feces. Meanwhile, sucralose and acesulfame-K did not increase food intake, body weight gain or liver weight, or fat in the epididymis or cecum. Only sucralose intake increased the concentration of hepatic cholesterol and cholic acid. Moreover, the relative concentration of butyrate and the ratio of secondary/primary bile acids in luminal metabolites increased with sucralose consumption in a dose-dependent manner. These results suggest that daily intake of maximum ADI levels of sucralose, but not acesulfame-K, affected the relative amount of the Clostridium cluster XIVa in fecal microbiome and cholesterol bile acid metabolism in mice.

  18. Non-Invasive Neuromodulation Using Time-Varying Caloric Vestibular Stimulation

    Science.gov (United States)

    Rogers, Lesco L.; Ade, Kristen K.; Nicoletto, Heather A.; Adkins, Heather D.; Laskowitz, Daniel T.

    2016-01-01

    Caloric vestibular stimulation (CVS) to elicit the vestibulo-ocular reflex has long been used in clinical settings to aid in the diagnosis of balance disorders and to confirm the absence of brainstem function. While a number of studies have hinted at the potential therapeutic applications of CVS, the limitations of existing devices have frustrated that potential. Current CVS irrigators use water or air during short-duration applications; however, this approach is not tenable for longer duration therapeutic protocols or home use. Here, we describe a solid-state CVS device we developed in order to address these limitations. This device delivers tightly controlled time-varying thermal waveforms, which can be programmed through an external control unit. It contains several safety features, which limit patients to the prescribed waveform and prevent the potential for temperature extremes. In this paper, we provide evidence that CVS treatment with time-varying, but not constant temperature waveforms, elicits changes in cerebral blood flow physiology consistent with the neuromodulation of brainstem centers, and we present results from a small pilot study, which demonstrate that the CVS can safely and feasibly be used longitudinally in the home setting to treat episodic migraine. Together, these results indicate that this solid-state CVS device may be a viable tool for non-invasive neuromodulation. PMID:27777829

  19. Krebs cycle enzymes from livers of old mice are differentially regulated by caloric restriction.

    Science.gov (United States)

    Hagopian, Kevork; Ramsey, Jon J; Weindruch, Richard

    2004-08-01

    Krebs cycle enzyme activities and levels of five metabolites were determined from livers of old mice (30 months) maintained either on control or on long-term caloric restriction (CR) diets (28 months). In CR mice, the cycle was divided into two major blocks, the first containing citrate synthase, aconitase and NAD-dependent isocitrate dehydrogenase which showed decreased activities, while the second block, containing the remaining enzymes, displayed increased activity (except for fumarase, which was unchanged). CR also resulted in decreased levels of citrate, glutamate and alpha-ketoglutarate, increased levels of malate, and unchanged levels of aspartate. The alpha-ketoglutarate/glutamate and malate/alpha-ketoglutarate ratios were higher in CR, in parallel with previously reported increases with CR in pyruvate carboxylase activity and glucagon levels, respectively. The results indicate that long-term CR induces a differential regulation of Krebs cycle in old mice and this regulation may be the result of changes in gene expression levels, as well as a complex interplay between enzymes, hormones and other effectors. Truncation of Krebs cycle by CR may be an important adaptation to utilize available substrates for the gluconeogenesis necessary to sustain glycolytic tissues, such as brain.

  20. Evaluation of dysphagia risk, nutritional status and caloric intake in elderly patients with Alzheimer's

    Directory of Open Access Journals (Sweden)

    Vanessa Fernanda Goes

    2014-04-01

    Full Text Available OBJECTIVE: to evaluate the risk of dysphagia and its relationship with the stage of Alzheimer's Disease, as well as the relationship between the risk of dysphagia and nutritional status and caloric intake in elderly people with Alzheimer's disease.METHODS: the sample consisted of 30 subjects of both genders with probable Alzheimer's disease. The stage of the disease, nutritional status, energy intake, and risk of dysphagia were assessed.RESULTS: it was found that increased risk of dysphagia is associated with the advance in the stages of Alzheimer's disease and that even patients in the early stages of disease have a slight risk of developing dysphagia. No association was found between nutritional status and the risk of dysphagia. High levels of inadequate intake of micronutrients were also verified in the patients.CONCLUSION: an association between dysphagia and the development of Alzheimer's disease was found. The results indicate the need to monitor the presence of dysphagia and the micronutrient intake in patients with Alzheimer's disease.

  1. [Index of Nutritional Purchasing Power Parity: comparison of caloric costs of a healthy versus an unhealthy diet].

    Science.gov (United States)

    Mendoza Velázquez, Alfonso

    2012-01-01

    Develop the Index of Nutritional Purchasing Power Parity (Nut3-CiO) as an instrument to compare the caloric costs of a healthy versus an unhealthy diet between regions or cities in a country over time. Indices of caloric prices were constructed and the "law of one price" was used to derive the Nut3-CiO index. Caloric inflation rates were obtained using basic descriptive statistics. The Nut3-CiO was applied in the major cities of Mexico during the period from January 1996 to December 2010. The statistical behavior of the Nut3-CiO revealed that, in Mexican cities, products for a typical diet are less expensive than products for a healthy diet. The findings showed a cyclical behavior to the index, a high correlation between inflation for the typical diet and inflation for the market basket, and a high persistence of prices. The Nut3-CiO index makes it possible to periodically compare the price differential of two types of diets-typical and healthy-between cities in a single country. This instrument could help health authorities identify the cities where it is easier or more difficult for consumers to access a typical or healthy diet in terms of cost. Furthermore, it makes it possible to estimate the percentage adjustment necessary in each city to attain levels of nutritional purchasing power parity.

  2. Islas de calor urbano en Tampico, México. Impacto del microclima a la calidad del hábitat

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Fuentes Pérez

    2014-01-01

    Full Text Available De todas las modificaciones climáticas por causa urbana, las térmicas son las más conocidas por los propios ciudadanos. La acción transformadora del espacio natural sobre el que se realiza el emplazamiento de la ciudad, llega a ser productora en gran medida de sus condiciones ambientales, incluida la climatología urbana. Todo proceso de urbanización sustituye los suelos y áreas naturales por superficies construidas, cuyos materiales se caracterizan por una baja reflectividad, con disminución de la capacidad de absorción de agua y un comportamiento térmico propicio para el almacenamiento y la emisión de calor. Estos elementos coadyuvan a realzar la temperatura atmosférica de la ciudad en relación con su entorno menos urbanizado a través de un fenómeno conocido como efecto de islas de calor urbano, produciendo un impacto del microclima a la calidad del hábitat. La presente investigación experimental aplicada tiene como objetivo, demostrar la metodología de investigación adoptada, para realizar las islas de calor urbanas en Tampico, México.

  3. Trombose induzida pelo calor endovenoso: relato de dois casos tratados com rivaroxabana e revisão da literatura

    Directory of Open Access Journals (Sweden)

    Walter Junior Boim de Araujo

    2016-01-01

    Full Text Available Resumo Define-se trombose induzida pelo calor endovenoso como a propagação do trombo a partir de uma veia superficial em direção a uma veia mais profunda. Em geral, é considerada clinicamente insignificante quando não há propagação do trombo para o sistema venoso profundo. Essa condição pode ser tratada com terapia anticoagulante, embora a observação pareça ser suficiente, principalmente para graus menores. Neste estudo, relatamos dois casos de trombose induzida pelo calor endovenoso que teriam indicação de heparina de baixo peso molecular até a resolução do quadro. Porém, optou-se pelo uso da rivaroxabana (15 mg de 12 em 12h, com resolução completa do trombo em 4 semanas (caso 1 e em 7 dias (caso 2. A rivaroxabana pode ser uma alternativa promissora no tratamento da trombose induzida pelo calor endovenoso avançada, pela simplicidade da posologia, sem comprometimento da eficácia ou da segurança. São necessários estudos prospectivos, randomizados e controlados que possibilitem melhor entendimento da condição e o desenvolvimento de recomendações mais definitivas sobre opções de prevenção e tratamento.

  4. Molecular simulation of caloric properties of fluids modelled by force fields with intramolecular contributions: Application to heat capacities

    Science.gov (United States)

    Smith, William R.; Jirsák, Jan; Nezbeda, Ivo; Qi, Weikai

    2017-07-01

    The calculation of caloric properties such as heat capacity, Joule-Thomson coefficients, and the speed of sound by classical force-field-based molecular simulation methodology has received scant attention in the literature, particularly for systems composed of complex molecules whose force fields (FFs) are characterized by a combination of intramolecular and intermolecular terms. The calculation of a thermodynamic property for a system whose molecules are described by such a FF involves the calculation of the residual property prior to its addition to the corresponding ideal-gas property, the latter of which is separately calculated, either using thermochemical compilations or nowadays accurate quantum mechanical calculations. Although the simulation of a volumetric residual property proceeds by simply replacing the intermolecular FF in the rigid molecule case by the total (intramolecular plus intermolecular) FF, this is not the case for a caloric property. We describe the correct methodology required to perform such calculations and illustrate it in this paper for the case of the internal energy and the enthalpy and their corresponding molar heat capacities. We provide numerical results for cP, one of the most important caloric properties. We also consider approximations to the correct calculation procedure previously used in the literature and illustrate their consequences for the examples of the relatively simple molecule 2-propanol, CH3CH(OH)CH3, and for the more complex molecule monoethanolamine, HO(CH2)2NH2, an important fluid used in carbon capture.

  5. Caloric Intake on the Sabbath: A Pilot Study of Contributing Factors to Obesity in the Orthodox Jewish Community.

    Science.gov (United States)

    Rosenberg, Deborah A; Swencionis, Charles; Segal-Isaacson, C J

    2016-10-01

    The American Orthodox Jewish community has specific cultural factors that may contribute to overweight and obesity. This study aimed to look at caloric intake on the Sabbath and its contribution to overweight and obesity. Twelve married or previously married women who identify themselves as Orthodox Jews were recruited to do 24-h food recalls over the phone. The participants were divided into three weight groups (normal, overweight, and obese) based on their BMI. The overweight and obese participants' data were combined into one group for the purposes of statistical testing. Paired t tests looking at the data for all participants showed significantly great caloric intake during an average Sabbath day than an average weekday [t(4) = 7.58, p intake on the Sabbath for the overweight-obese women compared to the normal weight women [F(1) = 7.83, p = 0.02]. No statistical difference was seen between the weekday energy intake of the normal weight women as compared to the combined group of overweight-obese women [F(1) = 0.501, p = 0.499]. These results support the hypotheses that all groups eat significantly more on the Sabbath than on weekdays, and overweight and obese individuals eat significantly more on the Sabbath than normal weight individuals. This supports the theory that caloric intake on the Sabbath is a contributing factor to overweight and obesity within the American Orthodox Jewish community.

  6. PROCEDIMIENTO DE CALIBRACIÓN EN TEMPERATURA Y FLUJO DE CALOR DE UN CALORÍMETRO DIFERENCIAL DE BARRIDO (DSC

    Directory of Open Access Journals (Sweden)

    Pablo E. Reynoso

    2016-01-01

    Full Text Available El calorímetro diferencial de barrido no es un dispositivo de medición absoluta, por lo que su utilización requiere indispensable mente una calibración. En esta contribución se presenta un procedimiento de calibración para el cual s e consideraron las temperaturas y calores de fusión aceptados en la literatura de 5 materiales puros . S e prepararon 6 muestras de dife rentes masas para cada material y s e sometió cada una de ellas a ci clos de calentamiento , desde temperatura ambiente hasta 50 ºC por encima de las temperaturas de fusión , utilizando 6 velocidades distintas por cada probeta. Luego, p ara determinar una relación de ajuste entre los datos experimentales obtenidos y los valores aceptados , se utilizó un método de regresión no lineal mediante un procedimiento matricial desarrollado en el entorno MATLAB . Los resultados obtenidos muestran una corrección con una desviación estándar de 1,2 ºC para el ajuste en temperatura y 2,1 5 J/g para el flujo de calor.

  7. General and persistent effects of high-intensity sweeteners on body weight gain and caloric compensation in rats.

    Science.gov (United States)

    Swithers, Susan E; Baker, Chelsea R; Davidson, T L

    2009-08-01

    In an earlier work (S. E. Swithers & T. L. Davidson, 2008), rats provided with a fixed amount of a yogurt diet mixed with saccharin gained more weight and showed impaired caloric compensation relative to rats given the same amount of yogurt mixed with glucose. The present 4 experiments examined the generality of these findings and demonstrated that increased body weight gain was also demonstrated when animals consumed a yogurt diet sweetened with an alternative high-intensity sweetener (acesulfame potassium; AceK) as well as in animals given a saccharin-sweetened base diet (refried beans) that was calorically similar but nutritionally distinct from low-fat yogurt. These studies also extended earlier findings by showing that body weight differences persist after saccharin-sweetened diets are discontinued and following a shift to a diet sweetened with glucose. In addition, rats first exposed to a diet sweetened with glucose still gain additional weight when subsequently exposed to a saccharin-sweetened diet. The results of these experiments add support to the hypothesis that exposure to weak or nonpredictive relationships between sweet tastes and caloric consequences may lead to positive energy balance.

  8. Nonnutritive, Low Caloric Substitutes for Food Sugars: Clinical Implications for Addressing the Incidence of Dental Caries and Overweight/Obesity

    Directory of Open Access Journals (Sweden)

    Michael W. Roberts

    2012-01-01

    Full Text Available Caries and obesity are two common conditions affecting children in the United States and other developed countries. Caries in the teeth of susceptible children have often been associated with frequent ingestion of fermentable sugars such as sucrose, fructose, glucose, and maltose. Increased calorie intake associated with sugars and carbohydrates, especially when associated with physical inactivity, has been implicated in childhood obesity. Fortunately, nonnutritive artificial alternatives and non-/low-caloric natural sugars have been developed as alternatives to fermentable sugars and have shown promise in partially addressing these health issues. Diet counseling is an important adjunct to oral health instruction. Although there are only five artificial sweeteners that have been approved as food additives by the Food and Drug Administration (FDA, there are additional five non-/low caloric sweeteners that have FDA GRAS (Generally Recognized as Safe designation. Given the health impact of sugars and other carbohydrates, dental professionals should be aware of the nonnutritive non-/low caloric sweeteners available on the market and both their benefits and potential risks. Dental health professionals should also be proactive in helping identify patients at risk for obesity and provide counseling and referral when appropriate.

  9. Utilização de sensoriamento remoto em análises de albedo e temperatura de superfície em Londrina - PR: contribuições para estudos de ilha de calor urbana

    Directory of Open Access Journals (Sweden)

    Nancy Laura Rios Gamarra

    2014-12-01

    Full Text Available Este trabalho avaliou o albedo (αs e a temperatura de superfície continental (Tsup provenientes de sensoriamento remoto, e a temperatura do ar (Tar medida in situ no intuito de caracterizar a Ilha de Calor Urbana (ICU na cidade de Londrina (Paraná. Foram utilizados dados de αs e Tsup obtidos do sensor MODIS, e medições in situ de Tar realizadas entre junho e agosto de 2011 por sensores meteorológicos instalados em 13 locais na cidade. Os dados de αs e Tsup foram utilizados para calcular um índice de urbanização (IU na região e posteriormente comparado com Tar. A análise dos dados de αs e Tsup foi consistente com as medições in situ, evidenciando sua aplicabilidade na avaliação espaço-temporal de fenômenos acoplados continente-atmosfera, tais como a ICU. A mancha urbana da cidade de Londrina apresentou valores de IU compreendido entre 18 e 20, bem maiores que as áreas mais vegetadas (14 - 16. Nesse sentido, o IU demonstrou-se ser uma metodologia útil para representar a evolução espaço-temporal de áreas urbanas, o que pode propiciar uma avaliação detalhada do impacto da mudança de cobertura de solo no clima local e regional. Além disso, os resultados indicam que dados obtidos via satélite podem auxiliar grandemente na quantificação da ICU, quando dados in situ estiverem indisponíveis.

  10. [Effects of enclosure on the caloric values of main plant species, litters, and communities in Leymus chinensis steppe in Xilin River Basin, Inner Mongolia].

    Science.gov (United States)

    Gao, Kai; Zhu, Tie-Xia; Wang, Qi-Bing; Han, Guo-Dong

    2012-04-01

    In August 2010, a sampling work was conducted in the plots of the Leymus chinensis steppe, which were fenced in 1979, 1999, and 2004, respectively, in Inner Mongolia Grassland Ecosystem Research Station (IMGERS), aimed to approach the effects of different time periods of enclosure on the caloric values of main plant species, litters, and commnities, and on the total energy storage per unit area. Enclosure had significant effects on the caloric values of the main plant species, litters, and communities, and on the total energy storage per unit area. The total energy storage per unit area in the plots fenced in 1979 and 1999 was significantly higher than that in the plot fenced in 2004, while the caloric values of the litters and communities were in adverse. No significant differences were observed between the plots fenced in 1979 and 1999, respectively. The caloric value of the same plant species varied significantly with the time period of enclosure, and that of different plant species presently definite differences. The caloric value of communities depended on the plant species in the communities, while the total energy storage per unit area depended on the biomass production of the steppe. Both the caloric value of communities and the total energy storage per unit area presented the same variation trend of fluctuation in a short term, but maintained at a stable level over a long period of enclosure, and ecologically reached enrgy balance finally.

  11. Serum concentrations and gene expression of sirtuin 1 in healthy and slightly overweight subjects after caloric restriction or resveratrol supplementation: A randomized trial.

    Science.gov (United States)

    Mansur, Antonio P; Roggerio, Alessandra; Goes, Marisa F S; Avakian, Solange D; Leal, Dalila P; Maranhão, Raul C; Strunz, Célia M C

    2017-01-15

    Sirtuin 1 (Sirt1) plays an important role in vascular biology, and influences aspects of age-dependent atherosclerosis. In animals, the sirtuin system is strongly influenced by resveratrol and caloric restriction, but its expression in humans is controversial. This study investigated the effects of resveratrol and caloric restriction on Sirt1 serum concentrations and vascular biomarkers in a healthy human population. Forty-eight healthy participants (24 women) aged 55-65years were randomized to either 30days of resveratrol administration (500mg/day) or caloric restriction (1000cal/day). Blood was collected at baseline and day 30. Laboratory data analyzed were triglycerides, total cholesterol, HDL, VLDL, LDL, apolipoprotein A1, apolipoprotein B, lipoprotein (a), non-esterified fatty acids (NEFA), glucose, insulin, oxidative stress, C-reactive protein, and Sirt1. Expression of the Sirt1 gene was analyzed using real-time PCR. Caloric restriction diminished the abdominal circumference and improved the lipid profile, but not resveratrol intervention. Resveratrol and caloric restriction increased serum concentrations of Sirt1, from 1.06±0.71 to 5.75±2.98ng/mL; presveratrol treatment. Caloric restriction and resveratrol significantly increased plasma concentrations of Sirt1. The long-term impact of these interventions on atherosclerosis should be assessed. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Exploring the Optical Transient Sky with the Palomar Transient Factory

    CERN Document Server

    Rau, Arne; Law, Nicholas M; Bloom, Joshua S; Ciardi, David; Djorgovski, George S; Fox, Derek B; Gal-Yam, Avishay; Grillmair, Carl C; Kasliwal, Mansi M; Nugent, Peter E; Ofek, Eran O; Quimby, Robert M; Reach, William T; Shara, Michael; Bildsten, Lars; Cenko, S Bradley; Drake, Andrew J; Filippenko, Alexei V; Helfand, David J; Helou, George; Howell, D Andrew; Poznanski, Dovi; Sullivan, Mark

    2009-01-01

    The Palomar Transient Factory (PTF) is a wide-field experiment designed to investigate the optical transient and variable sky on time scales from minutes to years. PTF uses the CFH12k mosaic camera, with a field of view of 7.9 deg^2 and a plate scale of 1 asec/pixel, mounted on the the Palomar Observatory 48-inch Samuel Oschin Telescope. The PTF operation strategy is devised to probe the existing gaps in the transient phase space and to search for theoretically predicted, but not yet detected, phenomena, such as fallback supernovae, macronovae, .Ia supernovae and the orphan afterglows of gamma-ray bursts. PTF will also discover many new members of known source classes, from cataclysmic variables in their various avatars to supernovae and active galactic nuclei, and will provide important insights into understanding galactic dynamics (through RR Lyrae stars) and the Solar system (asteroids and near-Earth objects). The lessons that can be learned from PTF will be essential for the preparation of future large sy...

  13. Data mining to estimate broiler mortality when exposed to heat wave Mineração de dados e estimativa da mortalidade alta de frangos quando expostos a onda de calor

    Directory of Open Access Journals (Sweden)

    Marcos Martinez Vale

    2008-01-01

    Full Text Available Heat waves usually result in losses of animal production since they are exposed to thermal stress inducing an increase in mortality and consequent economical losses. Animal science and meteorological databases from the last years contain enough data in the poultry production business to allow the modeling of mortality losses due to heat wave incidence. This research analyzes a database of broiler production associated to climatic data, using data mining techniques such as attribute selection and data classification (decision tree to model the impact of heat wave incidence on broiler mortality. The temperature and humidity index (THI was used for screening environmental data. The data mining techniques allowed the development of three comprehensible models for estimating specifically high mortality during broiler production. Two models yielded a classification accuracy of 89.3% by using Principal Component Analysis (PCA and Wrapper feature selection approaches. Both models obtained a class precision of 0.83 for classifying high mortality. When the feature selection was made by the domain experts, the model accuracy reached 85.7%, while the class precision of high mortality was 0.76. Meteorological data and the calculated THI from meteorological stations were helpful to select the range of harmful environmental conditions for broilers 29 and 42 days old. The data mining techniques were useful for building animal production models.As ondas de calor provocam perdas na produção animal pela sua exposição ao estresse por calor aumentando a mortalidade, e consequentemente, perdas econômicas. Bancos de dados zootécnicos e meteorológicos históricos podem conter informações que permitem modelar a mortalidade de frangos devido à incidência de ondas de calor. O objetivo foi analisar bancos de dados de frangos de corte associados a dados meteorológicos utilizando técnicas de mineração de dados, seleção de atributos e classificação (

  14. Perda de calor determinada pela exposição das alças intestinais em ratos Heat loss caused by bowel exposition to room temperature in rats

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Von Bahten

    2006-10-01

    Full Text Available OBJETIVO: Esta pesquisa tem por objetivo quantificar a perda de energia calórica que ocorre ao realizarmos uma laparotomia com exposição de alças intestinais à atmosfera em ratos; determinar a perda termodinâmica representada por watts/m² em função da superfície peritoneal exposta do animal e discutir meios de tratamento para a perda de calor. MÉTODO: Foram utilizados 30 ratos machos, Wistar, distribuídos em cinco grupos de seis animais cada, com idade de 8 a 9 semanas, com o peso entre 200 e 220g. No grupo A ou grupo controle, os animais foram submetidos a anestesia inalatória. No grupo B, os ratos foram submetidos a uma laparotomia mediana com exposição das alças intestinais. Nos grupos C, D e E, os ratos foram submetidos a uma laparotomia mediana com exposição das alças intestinais e tratados respectivamente, por gaze úmida, gaze seca e empacotamento com filme de poliéster. RESULTADOS: Observou-se uma significativa perda de energia calórica quando se realiza uma laparotomia com exposição das alças intestinais em ambiente não controlado, da ordem de 620,72 kJ/m² A análise da perda termodinâmica, em função da superfície corpórea exposta do rato, apresentou um valor de 382,97 W/m². CONCLUSÕES: Na avaliação dos diferentes tipos de tratamento utilizados para prevenir a perda de calor corpóreo, ficou evidente que a utilização do filme de poliéster (PVC foi o método mais efetivo na conservação do calor, em relação à gaze seca e, ou úmida respectivamente.BACKGROUND: This study has the intent to quantify the caloric energy loss that occurs when a laparotomy is done and the bowel is exposed to room temperature in rats; to find the thermodynamic loss measured in watt/m² over the rat peritoneal area exposed and discuss ways to manage that heat loss. METHODS: This research project used 30 male rats, Wistar, separated in 5 groups of 6 animals, from 8 to 9 weeks old and weighting between 200 to 220g. Group A

  15. Transient stability of LHC strands

    CERN Document Server

    Baynham, D Elwyn; Coombs, R C; Bauer, P; Wolf, R

    1999-01-01

    The Large Hadron Collider (LHC) machine will operate at 1.9 K in order to achieve the high bending fields required in the dipole magnets. The cable and coil matrix is designed to be 'porous' in order to allow the He II coolant to $9 penetrate within the cable for stability enhancement. This paper describes transient stability measurements and theoretical modelling carried out on single strands from the LHC cable. The experimental work has been carried out at the $9 Rutherford Appleton Laboratory under an agreement with CERN. The aim of the experimental work has been to measure the influence of the strand surface treatment on the quench energy. The surface treatment, oxidized copper, tin-silver, $9 nickel etc., determines the transient heat transfer coefficients to the He II under high heat flux, short timescale (approximately 20 microseconds) conditions. The test equipment, based on an inductive heating technique, is described $9 and quench energy measurements presented. The experimental results are compared ...

  16. Nonlinear Diffusion and Transient Osmosis

    Science.gov (United States)

    Akira, Igarashi; Lamberto, Rondoni; Antonio, Botrugno; Marco, Pizzi

    2011-08-01

    We investigate both analytically and numerically the concentration dynamics of a solution in two containers connected by a narrow and short channel, in which diffusion obeys a porous medium equation. We also consider the variation of the pressure in the containers due to the flow of matter in the channel. In particular, we identify a phenomenon, which depends on the transport of matter across nano-porous membranes, which we call “transient osmosis". We find that nonlinear diffusion of the porous medium equation type allows numerous different osmotic-like phenomena, which are not present in the case of ordinary Fickian diffusion. Experimental results suggest one possible candidate for transiently osmotic processes.

  17. Transient Ablation of Teflon Hemispheres

    Science.gov (United States)

    Arai, Norio; Karashima, Kei-ichi; Sato, Kiyoshi

    1997-01-01

    For high-speed entry of space vehicles into atmospheric environments, ablation is a practical method for alleviating severe aerodynamic heating. Several studies have been undertaken on steady or quasi-steady ablation. However, ablation is a very complicated phenomenon in which a nonequilibrium chemical process is associated with an aerodynamic process that involves changes in body shape with time. Therefore, it seems realistic to consider that ablation is an unsteady phenomenon. In the design of an ablative heat-shield system, since the ultimate purpose of the heat shield is to keep the internal temperature of the space vehicle at a safe level during entry, the transient heat conduction characteristics of the ablator may be critical in the selection of the material and its thickness. This note presents an experimental study of transient ablation of Teflon, with particular emphasis on the change in body shape, the instantaneous internal temperature distribution, and the effect of thermal expansion on ablation rate.

  18. Nonlinear Diffusion and Transient Osmosis

    Institute of Scientific and Technical Information of China (English)

    Akira Igarashi; Lamberto Rondon; Antonio Botrugno; Marco Pizzi

    2011-01-01

    We investigate both analytically and numerically the concentration dynamics of a solution in two containers connected by a narrow and short channel, in which diffusion obeys a porous medium equation. We also consider the variation of the pressure in the containers due to the flow of matter in the channel. In particular, we identify a phenomenon, which depends on the transport of matter across nano-porous membranes, which we call "transient osmosis". We find that nonlinear diffusion of the porous medium equation type allows numerous different osmotic-like phenomena, which are not present in the case of ordinary Fickian diffusion. Experimental results suggest one possible candidate for transiently osmotic processes.

  19. Transient stability and emergency control

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Comparability of emergency control strategies with different instability modes is the key issue to decide which control strategy to be implemented. This paper considers that the essential factor causing instability should be used to form a unified standard to assess the effectiveness of control strategies with different instability modes. Thus a switching control stabilization principle was proposed based on elimination of the unbalanced energy between mechanical and electrical energies of generator sets. Along this way, the difficulty of seeking a Lyapunov function was circumvented. According to the principle, an emergency control algorithm framework was established to handle transient stability assessment, control location selection and control amount evaluation. Within the framework, this paper studied instability mode transition, then proposed an algorithm based on prediction function and a new approach to normalized stability margin stemmed from static EEAC method, which can increase comparability of various control locations. The simulations on the New-England System verified the proposed emergency control method for stabilizing transient stability.

  20. Computer Aided Transient Stability Analysis

    Directory of Open Access Journals (Sweden)

    Nihad M. Al-Rawi

    2007-01-01

    Full Text Available A program for handling and improving the transient stability of the Iraqi Super Grid electrical network was developed. The idea was demonstrated by applying it to the outages of the main generating units. The methodology was built upon a state of increasing power transfer through the healthy portion of network during disturbances. There were three parts concerned; the first part was the developing of the load flow program using fast decoupled method and the transient stability program using Modified Euler’s method in the step by step solution, the second part was the engagement between the two programs, the third part was the application of the new program on the Iraqi supper grid network (400 kV.

  1. Relating Nutrient Uptake And Respiration With Metabolically Active Transient Storage

    Science.gov (United States)

    Argerich, A.; Haggerty, R.; Christensen, C.

    2009-12-01

    Quantification of water transient storage zones is critical to understand stream nutrient uptake, but the common method to measure transient storage parameters (based on the use of conservative solutes as hydrologic tracers) does not allow distinguishing among different transient storage compartments that contribute in different proportions to nutrient uptake. We use an alternative experimental approach, the Resazurin (Raz) “smart” tracer, which in combination with a conservative tracer is expected to give the relation between metabolically active transient storage (MATS) versus whole transient storage. Raz is a weakly fluorescent phenoxazine dye that undergoes an irreversible reduction to highly fluorescent Resorufin (hereafter referred as Rru) in the presence of aerobic respiration. We conducted a combined injection of Raz, NaCl, NH4, and PO4 in WS01 at H.J. Andrews Experimental Forest. The injection was performed during low-baseflow conditions (Qachieved plateau conditions in less than 15 hours after the injection began and recovered to pre-injection conditions 56 hours after the end of the injection. EC corrected by background conditions decreased with distance reflecting a dilution effect caused by the water gaining condition of the reach. Raz concentration increased and Rru concentration decreased along the reach reflecting the transformation of Raz to Rru with distance. The Rru to Raz ratio at surface water was correlated with instantaneous rates of net ecosystem production (NEP) measured over the whole reach. Percentage of surface water in wells during plateau ranged between 50% and 95%. Raz concentrations at wells were lower and Rru concentrations higher than those observed in adjacent surface water. The Rru to Raz ratio in the hyporheic zone was correlated to O2 consumption measured at wells. Nutrient concentrations were not available at the moment of writing this abstract but we hypothesize a correlation between nutrient uptake and Raz to Rru

  2. Trocador de calor e umidade: proteção contra infecções pulmonares? Estudo piloto Heat and moisture exchanger: protection against lung infections? Pilot study

    Directory of Open Access Journals (Sweden)

    Luciana Alcoforado

    2012-03-01

    Full Text Available O objetivo deste trabalho foi realizar um estudo bacteriológico comparativo entre os sistemas de umidificação aquoso aquecido (UAA e filtro trocador de calor e umidade (FTCU quanto à colonização bacteriana e a incidência de infecção respiratória em pacientes submetidos à ventilação mecânica (VM. Trata-se de uma pesquisa prospectiva, controlada e randomizada, na qual 15 pacientes internados na Unidade de Terapia Intensiva (UTI foram distribuídos em dois grupos. O primeiro fez uso de UAA (n=7 e o outro de FTCU (n=8. Foram coletadas amostras da secreção traqueal, condensado do circuito e FTCU na admissão do paciente, no quarto e oitavo dias, e realizada análise bacteriológica dos mesmos. Quanto às características antropométricas, não observou-se diferenças entre os grupos estudados. A prevalência de pneumonia associada à ventilação (PAV foi de 57,1% no UAA e 62,5% no FTCU. Ao realizar a análise bacteriológica quantitativa entre eles, não foram observadas variações, sugerindo não haver diferença na prevenção de PAV entre os sistemas de umidificação; porém a presença das mesmas bactérias na secreção traqueal e no condensado e ausência destas na membrana do FTCU podem indicar que a principal fonte de contaminação é o próprio paciente.The aim of this study was to conduct a bacteriological research comparing the aqueous heated humidification systems (HH and filter heat and moisture exchanger (FHME and to bacterial colonization and the incidence of respiratory infection in patients undergoing mechanical ventilation. It is a prospective, controlled trial, in that 15 intensive care unit (ICU patients were divided into two groups. The first made use of HH (n=7 and the other, FHME (n=8. We collected samples of tracheal secretions, and condensate circuit FHME at admission in the fourth and eighth day and bacteriological analysis of the same place. Regarding the anthropometric characteristics, no differences

  3. ATLAS discoveries of optical transients

    Science.gov (United States)

    Tonry, J.; Denneau, L.; Stalder, B.; Heinze, A.; Sherstyuk, A.; Rest, A.; Smith, K. W.; Smartt, S. J.

    2016-09-01

    We report the following transients found by the ATLAS survey (see Tonry et al. ATel #8680). ATLAS is a twin 0.5m telescope system on Haleakala and Mauna Loa. The first unit is operational on Haleakala is robotically surveying the sky. Two filters are used, cyan and orange (denoted c and o, all mags in AB system), more information is on http://www.fallingstar.com.

  4. ATLAS discoveries of optical transients

    Science.gov (United States)

    Tonry, J.; Denneau, L.; Stalder, B.; Heinze, A.; Sherstyuk, A.; Rest, A.; Smith, K. W.; Smartt, S. J.

    2016-10-01

    We report the following transients found by the ATLAS survey (see Tonry et al. ATel #8680). ATLAS is a twin 0.5m telescope system on Haleakala and Mauna Loa. The first unit is operational on Haleakala is robotically surveying the sky. Two filters are used, cyan and orange (denoted c and o, all mags in AB system), more information is on http://www.fallingstar.com.

  5. Persistent memories in transient networks

    OpenAIRE

    Babichev, Andrey; Dabaghian, Yuri

    2016-01-01

    Spatial awareness in mammals is based on an internalized representation of the environment, encoded by large networks of spiking neurons. While such representations can last for a long time, the underlying neuronal network is transient: neuronal cells die every day, synaptic connections appear and disappear, the networks constantly change their architecture due to various forms of synaptic and structural plasticity. How can a network with a dynamic architecture encode a stable map of space? W...

  6. Simulation Model of a Transient

    DEFF Research Database (Denmark)

    Jauch, Clemens; Sørensen, Poul; Bak-Jensen, Birgitte

    2005-01-01

    This paper describes the simulation model of a controller that enables an active-stall wind turbine to ride through transient faults. The simulated wind turbine is connected to a simple model of a power system. Certain fault scenarios are specified and the turbine shall be able to sustain operation...... in case of such faults. The design of the controller is described and its performance assessed by simulations. The control strategies are explained and the behaviour of the turbine discussed....

  7. Transient virulence of emerging pathogens.

    Science.gov (United States)

    Bolker, Benjamin M; Nanda, Arjun; Shah, Dharmini

    2010-05-06

    Should emerging pathogens be unusually virulent? If so, why? Existing theories of virulence evolution based on a tradeoff between high transmission rates and long infectious periods imply that epidemic growth conditions will select for higher virulence, possibly leading to a transient peak in virulence near the beginning of an epidemic. This transient selection could lead to high virulence in emerging pathogens. Using a simple model of the epidemiological and evolutionary dynamics of emerging pathogens, along with rough estimates of parameters for pathogens such as severe acute respiratory syndrome, West Nile virus and myxomatosis, we estimated the potential magnitude and timing of such transient virulence peaks. Pathogens that are moderately evolvable, highly transmissible, and highly virulent at equilibrium could briefly double their virulence during an epidemic; thus, epidemic-phase selection could contribute significantly to the virulence of emerging pathogens. In order to further assess the potential significance of this mechanism, we bring together data from the literature for the shapes of tradeoff curves for several pathogens (myxomatosis, HIV, and a parasite of Daphnia) and the level of genetic variation for virulence for one (myxomatosis). We discuss the need for better data on tradeoff curves and genetic variance in order to evaluate the plausibility of various scenarios of virulence evolution.

  8. Regulation of cardiac myocyte contractility by phospholemman: Na+/Ca2+ exchange versus Na+ -K+ -ATPase.

    Science.gov (United States)

    Song, Jianliang; Zhang, Xue-Qian; Wang, JuFang; Cheskis, Ellina; Chan, Tung O; Feldman, Arthur M; Tucker, Amy L; Cheung, Joseph Y

    2008-10-01

    Phospholemman (PLM) regulates cardiac Na(+)/Ca(2+) exchanger (NCX1) and Na(+)-K(+)-ATPase in cardiac myocytes. PLM, when phosphorylated at Ser(68), disinhibits Na(+)-K(+)-ATPase but inhibits NCX1. PLM regulates cardiac contractility by modulating Na(+)-K(+)-ATPase and/or NCX1. In this study, we first demonstrated that adult mouse cardiac myocytes cultured for 48 h had normal surface membrane areas, t-tubules, and NCX1 and sarco(endo)plasmic reticulum Ca(2+)-ATPase levels, and retained near normal contractility, but alpha(1)-subunit of Na(+)-K(+)-ATPase was slightly decreased. Differences in contractility between myocytes isolated from wild-type (WT) and PLM knockout (KO) hearts were preserved after 48 h of culture. Infection with adenovirus expressing green fluorescent protein (GFP) did not affect contractility at 48 h. When WT PLM was overexpressed in PLM KO myocytes, contractility and cytosolic Ca(2+) concentration ([Ca(2+)](i)) transients reverted back to those observed in cultured WT myocytes. Both Na(+)-K(+)-ATPase current (I(pump)) and Na(+)/Ca(2+) exchange current (I(NaCa)) in PLM KO myocytes rescued with WT PLM were depressed compared with PLM KO myocytes. Overexpressing the PLMS68E mutant (phosphomimetic) in PLM KO myocytes resulted in the suppression of I(NaCa) but had no effect on I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the PLMS68E mutant were depressed compared with PLM KO myocytes overexpressing GFP. Overexpressing the PLMS68A mutant (mimicking unphosphorylated PLM) in PLM KO myocytes had no effect on I(NaCa) but decreased I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the S68A mutant were similar to PLM KO myocytes overexpressing GFP. We conclude that at the single-myocyte level, PLM affects cardiac contractility and [Ca(2+)](i) homeostasis primarily by its direct

  9. PREFACE: 16th International Conference on Calorimetry in High Energy Physics (CALOR 2014)

    Science.gov (United States)

    Novotny, Rainer W.

    2015-02-01

    The XVIth International Conference on Calorimetry in High Energy Physics - CALOR 2014 - was held in Giessen, Germany from 6-11 April 2014 at the Science Campus of the University. It was hosted by the Justus-Liebig-University and the HIC for FAIR Helmholtz International Center. The series of conferences on calorimetry were started in 1990 at Fermilab and are focusing primarily on operating and future calorimeter systems within the Hadron and High-Energy Physics community without neglecting the impact on other fields such as Astrophysics or Medical Imaging. Confirmed by the impressive list of over 70 oral presentations, 5 posters and over 100 attendees, the field of calorimetry appears alive and attractive. The present volume contains the written contributions of almost all presentations which can be found at http://calor2014.de. Time slots of 15 or 30 minutes including discussion were allocated. The conference was accompanied by a small exhibition of several industrial companies related to the field. The day before the opening of the scientific program, Richard Wigmans gave an excellent and vivid tutorial on basic aspects on calorimetry meant as an introduction for students and conference attendees new in the field. The opening ceremony was used to give an impression of the present and future status and the scientific program of the new FAIR facility nearby at Darmstadt presented by Klaus Peters from GSI. The conference program of the first day was dedicated to the performance and required future upgrade of the LHC experiments, dominated by ATLAS, CMS and LHCb. The program of the next day contained specific aspects on electronics and readout as well as calorimetry in outer space. Several contributions discussed in detail new concepts for hadron calorimeters within the CALICE collaboration completed by a session on sampling calorimeters. The next sections were dedicated to operating and future calorimeters at various laboratories and covering a wide range of

  10. NA44 experiment

    CERN Document Server

    1990-01-01

    General view of NA44 experiment. NA44 is one of the seven experiments (NA44, NA45, NA49, NA50, NA52, WA97/NA57 and WA98) involved in CERN'S Heavy Ion programme which provided evidence for the existence of a new state of matter in which quarks, instead of being bound up into more complex particles such as protons and neutrons, are liberated and roam freely. Theory predicts that this state must have existed at about 10 microseconds after the Big Bang, before the formation of matter as we know it today.

  11. Método de fio quente na determinação das propriedades térmicas de polímeros Hot wire technique in the determination of thermal properties of polymers

    Directory of Open Access Journals (Sweden)

    Wilson N. dos Santos

    2004-12-01

    Full Text Available A técnica de fio quente paralelo normalizada para a determinação da condutividade térmica de materiais cerâmicos foi empregada na determinação das propriedades térmicas de polímeros. As amostras foram preparadas em forma de paralelepípedos retangulares, com dimensões de (230x80x30mm. Neste trabalho, a condutividade térmica e o calor específico foram simultaneamente determinados a partir do mesmo transiente térmico experimental e a difusividade térmica foi calculada a partir dessas duas propriedades. Cinco diferentes polímeros com diferentes estruturas a temperatura ambiente foram selecionados neste trabalho. Os cálculos foram feitos utilizando-se um método de ajuste por regressão não linear, de tal maneira que todos os pontos experimentais obtidos são considerados nos cálculos dessas propriedades térmicas. O equipamento utilizado neste trabalho é totalmente automatizado. A reprodutibilidade dos resultados foi muito boa com respeito à condutividade térmica, obtendo-se um desvio máximo de apenas 0,5% entre os valores máximo e mínimo para todas as amostras ensaiadas, mesmo introduzindo propositadamente alguns defeitos no arranjo experimental, em relação ao modelo teórico. Todavia, pequenos desvios do modelo teórico podem causar drásticas influências nos valores de calor específico, obtendo-se desvios de até 32% em relação ao arranjo experimental correto. Os resultados experimentais foram então comparados com aqueles encontrados na literatura. As discrepâncias observadas entre alguns desses valores podem estar associadas ao grau de cristalinidade ou à história térmica da amostra, ficando assim mostrada a aplicabilidade desta técnica na determinação das propriedades térmicas de polímeros.The hot wire parallel technique standardized for determining thermal conductivity of ceramic materials was employed in the determination of thermal properties of polymers. Samples were prepared in shape of rectangular

  12. Magneto-caloric effect in the pseudo-binary intermetallic YPrFe{sub 17} compound

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, Pablo [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n, 33007 Oviedo (Spain); Gorria, Pedro, E-mail: pgorria@uniovi.es [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n, 33007 Oviedo (Spain); Sanchez Llamazares, Jose L. [Division de Materiales Avanzados, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la presa San Jose 2055, CP 78216, San Luis Potosi (Mexico); Perez, Maria J. [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n, 33007 Oviedo (Spain); Franco, Victorino [Departamento de Fisica de la Materia Condensada, ICMSE-CSIC, Universidad de Sevilla, P.O. Box 1065, 41080 Sevilla (Spain); Reiffers, Marian; Kovac, Jozef [Institute of Experimental Physics, Watsonova 47, SK-04001 Kosice (Slovakia); Puente-Orench, Ines [Institute Laue Langevin, 6 rue Jules Horowitz, 38042 Grenoble (France); Blanco, Jesus A. [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n, 33007 Oviedo (Spain)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer YPrFe{sub 17} exhibits a broad {Delta}S{sub M}(T) associated with the ferro-to-paramagnetic phase transition (T{sub C} Almost-Equal-To 290 K). Black-Right-Pointing-Pointer We obtain |{Delta}S{sub M}| Almost-Equal-To 2.3 J kg{sup -1} K{sup -1} and RCP Almost-Equal-To 100 J kg{sup -1}for a magnetic field change of 1.5 T. Black-Right-Pointing-Pointer A single master curve for {Delta}S{sub M} is found when compared with other isostructural R{sub 2}Fe{sub 17} binary alloys. - Abstract: We have synthesized the intermetallic YPrFe{sub 17} compound by arc-melting. X-ray and neutron powder diffraction show that the crystal structure is rhombohedral with R3{sup Macron }m space group (Th{sub 2}Zn{sub 17}-type). The investigated compound exhibits a broad isothermal magnetic entropy change {Delta}S{sub M}(T) associated with the ferro-to-paramagnetic phase transition (T{sub C} Almost-Equal-To 290 K). The |{Delta}S{sub M}| ( Almost-Equal-To 2.3 J kg{sup -1} K{sup -1}) and the relative cooling power ( Almost-Equal-To 100 J kg{sup -1}) have been calculated for applied magnetic field changes up to 1.5 T. A single master curve for {Delta}S{sub M} under different values of the magnetic field change can be obtained by a rescaling of the temperature axis. The results are compared and discussed in terms of the magneto-caloric effect in the isostructural R{sub 2}Fe{sub 17} (R = Y, Pr and Nd) binary intermetallic alloys.

  13. Tecnologías emergentes para la conservación de alimentos sin calor

    Directory of Open Access Journals (Sweden)

    Fernández Molina, Juan José

    2001-01-01

    Full Text Available Not available

    Se han investigado los principios básicos de tres tecnologías emergentes para pasteurizar y esterilizar alimentos sin empleo del calor Mediante numerosos estudios se ha comprobado la efectividad de los campos eléctricos pulsantes de alta intensidad (CEPAI, los pulsos de luz (PL y los campos magnéticos oscilantes (CMO en la destrucción de microorganismos y enzimas de sistemas alimentarios. En la inactivación microbiana por CEPA!, el blanco principal es la membrana celular que, al ser sometida a campos eléctricos de alta intensidad, se hace permeable formando huecos o poros cuyo tamaño se incrementa a medida que aumenta la intensidad del campo eléctrico o el tiempo de tratamiento o se reduce la resistencia iónica del medio de pulsación. Por otra parte, los PL inducen reacciones fotoquímicas y fototérmicas en los alimentos, causando la muerte de gran cantidad de microorganismos, especialmente en productos alimenticios envasados. Los CMO producen simulación o inhibición en el crecimiento y reproducción de los microorganismos, un simple pulso de intensidad de 5-10 teslas y frecuencias de 5-500 kHz es suficiente para reducir el número de microorganismos en un mínimo de 2 ciclos logarítmicos. Se ha comprobado que estas tecnologías alargan la vida de anaquel de diversos productos alimenticios y pueden ser consideradas como sustitutos parciales de los procesos convencionales de pasteurización y esterilización de alimentos por tratamientos térmicos.

  14. The ketogenic diet: initiation at goal calories versus gradual caloric advancement.

    Science.gov (United States)

    Bansal, Seema; Cramp, Laura; Blalock, Dan; Zelleke, Tesfaye; Carpenter, Jessica; Kao, Amy

    2014-01-01

    Inpatient initiation of the ketogenic diet has historically involved fasting followed by gradual advancement of calories and/or diet ratio. Complications during this initiation period are common. We sought to determine if the initiation of the diet at goal calories would reduce these complications while maintaining efficacy. Sixty patients were admitted to a tertiary care hospital for elective initiation of the ketogenic diet between October 2007 and January 2013. All patients were placed on a ketogenic diet initiation pathway. In 2010, the pathway was modified from gradual caloric advancement to initiation at goal calories. We selected 30 consecutive patients before and after the change for comparison. Each child's record was reviewed for the occurrence of hypoglycemia, number of days to reach full ketosis (defined as 4 + urine ketones), acidosis requiring commencement of sodium citrate, length of admission, and long-term efficacy. Both methods of initiation had similar rates of dehydration, vomiting, lethargy, and irritability. More patients initiated at goal received sodium citrate (P = 0.005); however, mean daily values of carbon dioxide were not significantly different. Onset of ketosis was slightly delayed (P = 0.009) in patients initiated at goal, but length of stay was not affected (P > 0.1). Hypoglycemia was uncommon and rates were similar between the groups. Efficacy at 3 months was better in patients initiated at full calories (P ketogenic diet full calories is a reasonable alternative to the current standard practice of gradual advancement of calories and/or diet ratio. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Leaf Caloric Value from Tropical to Cold-Temperate Forests: Latitudinal Patterns and Linkage to Productivity.

    Science.gov (United States)

    Song, Guangyan; Hou, Jihua; Li, Ying; Zhang, Jiahui; He, Nianpeng

    2016-01-01

    Leaf caloric value (LCV) reflects the capacity of a leaf to fix and accumulate solar energy through photosynthesis. We systematically investigated the LCV of 745 plant species in 9 forests, representing a range of tropical to cold-temperate forests along the 4700-km North-South Transect of Eastern China. The goals were to explore the latitudinal patterns of LCV at the levels of species, plant functional group, and community and to establish the relationship between LCV and gross primary productivity (GPP). Our results showed that LCV for all species ranged from 12.85 to 22.15 KJ g-1 with an average of 18.46 KJ g-1. Plant functional groups had a significant influence on LCV, with trees > shrubs > herbs, conifers > broadleaved trees, and evergreens > deciduous trees. The different values of LCV represented the long-term evolution and adaptation of plant species to different environments. Unexpectedly, no apparent latitudinal trends of LCV at community level were observed, although LCV at the species level clearly decreased with increasing latitude. Use efficiency of LCV (CUE, gC KJ-1), defined as the ratio of GPP to total LCV at the community level, varied quadratic with latitude and was lower in the middle latitudes. Climate (temperature and precipitation) may explain 52.9% of the variation in spatial patterns of CUE, which was positively correlated with aridity. Our findings are the first large-scale report of the latitudinal patterns of LCV in forests at the species, plant functional group, and community levels and provide new insights into the relationship between LCV and ecosystem functions in forest communities.

  16. Effect of exercise on the caloric intake of breast cancer patients undergoing treatment

    Directory of Open Access Journals (Sweden)

    C.L. Battaglini

    2008-08-01

    Full Text Available The purpose of this study was to examine the effects of an exercise intervention on the total caloric intake (TCI of breast cancer patients undergoing treatment. A secondary purpose was to determine whether or not a relationship existed between changes in TCI, body fat composition (%BF, and fatigue during the study, which lasted 6 months. Twenty females recently diagnosed with breast cancer, scheduled to undergo chemotherapy or radiation, were assigned randomly to an experimental (N = 10 or control group (N = 10. Outcome measures included TCI (3-day food diary, %BF (skinfolds, and fatigue (revised Piper Fatigue Scale. Each exercise session was conducted as follows: initial cardiovascular activity (6-12 min, followed by stretching (5-10 min, resistance training (15-30 min, and a cool-down (approximately 8 min. Significant changes in TCI were observed among groups (F1,18 = 8.582; P = 0.009, at treatments 2 and 3, and at the end of the study [experimental (1973 ± 419, control (1488 ± 418; experimental (1946 ± 437, control (1436 ± 429; experimental (2315 ± 455, control (1474 ± 294, respectively]. A significant negative correlation was found (Spearman rho(18 = -0.759; P < 0.001 between TCI and %BF and between TCI and fatigue levels (Spearman rho(18 = -0.541; P = 0.014 at the end of the study. In conclusion, the results of this study suggest that an exercise intervention administered to breast cancer patients undergoing medical treatment may assist in the mitigation of some treatment side effects, including decreased TCI, increased fatigue, and negative changes in body composition.

  17. Leaf Caloric Value from Tropical to Cold-Temperate Forests: Latitudinal Patterns and Linkage to Productivity.

    Directory of Open Access Journals (Sweden)

    Guangyan Song

    Full Text Available Leaf caloric value (LCV reflects the capacity of a leaf to fix and accumulate solar energy through photosynthesis. We systematically investigated the LCV of 745 plant species in 9 forests, representing a range of tropical to cold-temperate forests along the 4700-km North-South Transect of Eastern China. The goals were to explore the latitudinal patterns of LCV at the levels of species, plant functional group, and community and to establish the relationship between LCV and gross primary productivity (GPP. Our results showed that LCV for all species ranged from 12.85 to 22.15 KJ g-1 with an average of 18.46 KJ g-1. Plant functional groups had a significant influence on LCV, with trees > shrubs > herbs, conifers > broadleaved trees, and evergreens > deciduous trees. The different values of LCV represented the long-term evolution and adaptation of plant species to different environments. Unexpectedly, no apparent latitudinal trends of LCV at community level were observed, although LCV at the species level clearly decreased with increasing latitude. Use efficiency of LCV (CUE, gC KJ-1, defined as the ratio of GPP to total LCV at the community level, varied quadratic with latitude and was lower in the middle latitudes. Climate (temperature and precipitation may explain 52.9% of the variation in spatial patterns of CUE, which was positively correlated with aridity. Our findings are the first large-scale report of the latitudinal patterns of LCV in forests at the species, plant functional group, and community levels and provide new insights into the relationship between LCV and ecosystem functions in forest communities.

  18. Mild caloric restriction up-regulates the expression of prohibitin: A proteome study

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Shoko; Masuda, Junko; Shimagami, Hiroshi [Department of Applied Biological Chemistry, The University of Tokyo, Tokyo (Japan); Ohta, Yutaka; Kanda, Tomomasa [Research Laboratories for Health and Gustatory Science, Asahi Breweries Limited, Ibaraki (Japan); Saito, Kenji [Department of Applied Biological Chemistry, The University of Tokyo, Tokyo (Japan); Corporate Sponsored Research Program ' Food for Life' , The University of Tokyo, Tokyo (Japan); Kato, Hisanori, E-mail: akatoq@mail.ecc.u-tokyo.ac.jp [Department of Applied Biological Chemistry, The University of Tokyo, Tokyo (Japan); Corporate Sponsored Research Program ' Food for Life' , The University of Tokyo, Tokyo (Japan)

    2011-02-18

    Research highlights: {yields} Proteomic analysis was performed to elucidate physiological alterations induced by mild CR. {yields} The results suggest good reproducibility and possibility to grasp the important response of CR. {yields} The increase in prohibitin abundance was observed in CR groups by proteomic analysis. {yields} We hypothesize that prohibitin might be involved in the longevity induced by CR. -- Abstract: Caloric restriction (CR) is well known to expand lifespan in a variety of species and to retard many age-related diseases. The effects of relatively mild CR on the proteome profile in relation to lifespan have not yet been reported, despite the more extensive studies of the stricter CR conditions. Thus, the present study was conducted to elucidate the protein profiles in rat livers after mild CR for a relatively short time. Young growing rats were fed CR diets (10% and 30% CR) for 1 month. We performed the differential proteomic analysis of the rat livers using two-dimensional electrophoresis combined with MALDI-TOF mass spectrometry. The most remarkable protein among the differentially expressed proteins was found to be prohibitin, the abundance of which was increased by 30% CR. Prohibitin is a ubiquitously expressed protein shown to suppress cell proliferation and to be related to longevity. The increase in prohibitin was observed both in 10% and 30% CR by Western blot analysis. Furthermore, induction of AMP-activated kinase (AMPK) protein, related to the actions of prohibitin in promoting longevity, was observed. The increased prohibitin level in response to subtle CR suggests that this increase may be one of the early events leading to the expansion of lifespan in response to CR.

  19. Perda de eletrólitos durante uma competição de duatlo terrestre no calor Electrolyte losses during a land based duatlhon competition in the heat

    Directory of Open Access Journals (Sweden)

    Geórgia Franco Becker

    2011-06-01

    Full Text Available Eventos esportivos prolongados, como o duatlo (6 km corrida, 26 km ciclismo e 4 km corrida podem levar o atleta a um desequilíbrio hidroeletrolítico, devido a perdas elevadas de suor, em especial se realizados no calor. O presente estudo avaliou as perdas de sódio (Na+, potássio (K+ e cloreto (Cl- durante uma competição de duatlo realizada no calor (31,2 °C e 51% de umidade relativa do ar, analisando a composição do suor e os níveis sanguíneos destes eletrólitos. Doze atletas fizeram parte deste estudo. Coletas de sangue foram realizadas antes e após a competição, e o suor foi coletado utilizando-se adesivos específicos. O tempo médio para completar a competição foi de 85,0 ± 6,57 min. O percentual de desidratação foi 3,0 ± 0,92%. A reposição de líquidos perdidos durante a competição foi 31 ± 18,7%. A taxa de sudorese foi 1,86 ± 0,56 L•h-1. A concentração de Na+, K+ e Cl- no suor foi 71 ± 26,05 mmol•L-1, 5,43 ± 1,98 mmol•L-1 e 58,93 ± 25,99 mmol•L¹, respectivamente. A perda total de Na+, K+ e Cl- no suor foi 132,11 ± 62,82 mmol, 10,09 ± 5,01 mmol e 109,75 ± 58,49 mmol, respectivamente. Em conclusão, os atletas não ingeriram líquido suficiente para repor o volume de fluidos perdido. Além disto, os participantes apresentaram elevada taxa de sudorese acompanhada de perdas de Na+, K+ e Cl-. Apesar disso, não ocorreram alterações nas concentrações de eletrólitos séricos.Prolonged sports events such as duathlon (6 km running, 26 km cycling and 4 km running, may lead the athlete to a fluid and electrolyte imbalance, due to high sweat rates, especially in a hot environment. The present study evaluated sodium (Na+, potassium (K+ and chloride (Cl- losses during a duathlon competition performed in the heat (31,2 ºC and 51% relative humidity, analyzing the sweat composition and blood levels of these electrolytes. Twelve athletes took part in this study. Blood samples were obtained pre- and post

  20. Developmental regulation of intracellular calcium transients during cardiomyocyte differentiation of mouse embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    Ji-dong FU; Hui-mei YU; Rong WANG; Ji LIANG; Huang-tian YANG

    2006-01-01

    Aim: To investigate the developmental regulation of intracellular Ca2+ transients, an essential event in excitation-contraction coupling, during cardiomyocyte differentiation. Methods: Using the embryonic stem (ES) cell in vitro differentiation system and pharmacological intervention, we investigated the molecular and functional regulation of Ca2+ handling proteins on the Ca2+ transients at early, intermediate and later differentiation stages of ES cell-derived cardiomyocytes (ESCM). Results: Nifedipine, a selective antagonist of L-type Ca2+ channels, totally blocked Ca2+ transients even in the condition of field-electric stimulation in ESCM at three differentiation stages. The Ca2+ transients of ESCM were also inhibited by both ryanodine [an inhibitor of ryanodine receptors (RyRs)] and 2-aminoethoxydipheylborate [2-APB, an inhibitor of inositol-1,4,5-trisphosphate receptors (IP3Rs)]. The inhibitory effect of ryanodine increased with the time of differentiation, while the effect of 2-APB decreased with the differentiation. Thapsigargin, an inhibitor of SR Ca2+-pump ATPase, inhibited Ca2+ transients equally at three differentiation stages that matched the expression profile. Na+ free solution, which inhibits Na+-Ca2+ exchanger (NCX) to extrude Ca2+ from cytosol, did not affect the amplitude of Ca2+ transients of ESCM until the latter differentiation stage, but it significantly enhanced the basal Ca2+concentration. Conclusion: The Ca2+ transients in ESCM depend on both the sarcolemmal Ca2+ entry via L-type Ca2+ channels and the SR Ca2+ release from RyRs and IP3Rs even at the early differentiation stage; but NCX seems not to regulate the peak of Ca2+ transients until the latter differentiation stage.

  1. Determinación del Coeficiente de Transferencia de Calor a Través de una Aplicación de Computadoras Determination of Heat Transfer Coefficient through Computer Application

    OpenAIRE

    2010-01-01

    Se describe un procedimiento de evaluación del coeficiente de transferencia de calor en operaciones industriales. Se presenta un modelo matemático sencillo de determinación del coeficiente convectivo de transferencia de calor usando el software DCAL (Determinación de Coeficiente de Transferencia de Calor durante un Calentamiento). Para validar el modelo se usaron datos experimentales de muestras procesadas por tratamiento térmico, utilizando diferentes temperaturas y tiempos de proceso. Los d...

  2. The urban climate: urban heat island of Salamanca El clima de las ciudades: isla de calor de Salamanca

    Directory of Open Access Journals (Sweden)

    Mª Salud Alonso García

    2004-12-01

    Full Text Available We have determined the existence of the urban heat island (UHI in a medium-sized city, with an extreme climate and few important foci of industrial pollution. It was seen that urban warming can arise in cities of these characteristics, being able to influence in the alive beings of the zone. By comparing the temperature series in an urban area and those from a nearby rural area, we studied the temporal evolution of the intensity of the UHI for the three-year period between 1996 and 1998. We detected two phenomenons: nocturnal heat island, when the difference of temperature between city and rural zone is positive, and diurnal heat island, when is negative. The most intense nocturnal heat island was seen in autumn, and the most intense diurnal heat island was seen in spring. Statistical study of the annual series corresponding to the night-time heat island permits a definition for Salamanca: a weak island, such as the one showing an intensity lower than 2.0 oC, a moderate island, if the intensity lies between 2.0 oC and 4.0 oC, and an intense island when a values greater than 4.0 oC is passed.En este trabajo se ha determinado la existencia de la isla de calor urbana (ICU, en una ciudad de tamaño medio, con un clima extremado y focos industriales de poca actividad. Con lo que se puede comprobar cómo afecta el calentamiento urbano a ciudades de estas características, pudiendo influir en los seres vivos de la zona. La existencia del fenómeno isla de calor, y su evolución en el tiempo, se han observado comparando los datos de temperatura registrados en una estación meteorológica situada en la ciudad, con los de otra estación fuera del radio de acción de la urbe, durante el período 1996-1998. Se han detectado dos fenómenos: la isla de calor nocturna, cuando la diferencia térmica entre la ciudad y la zona rural es positiva, que presenta sus valores más altos en otoño, y la isla de calor diurna, cuando la diferencia es negativa, que

  3. of Transient Flows in Turbomachines

    Directory of Open Access Journals (Sweden)

    Alexander Wiedermann

    1999-01-01

    Full Text Available This paper focuses on development and validation of a viscous solver for the computation of unsteady flows in turbomachinery blade rows and stages consisting of rotors and stators. The code has been evolved from steady-state single flow solvers developed by Wiedermann based on time-marching finite difference schemes. A two-equation eddy viscosity model is applied, and the wall boundary conditions are determined by the y+-distance of the first grid line away from the wall. For the solution of transient flow fields the original time-stepping algorithm is replaced by a time-accurate scheme.

  4. Transient eddy current flow metering

    CERN Document Server

    Forbriger, Jan

    2015-01-01

    Measuring local velocities or entire flow rates in liquid metals or semiconductor melts is a notorious problem in many industrial applications, including metal casting and silicon crystal growth. We present a new variant of an old technique which relies on the continuous tracking of a flow-advected transient eddy current that is induced by a pulsed external magnetic field. This calibration-free method is validated by applying it to the velocity of a spinning disk made of aluminum. First tests at a rig with a flow of liquid GaInSn are also presented.

  5. Critical states of transient chaos

    CERN Document Server

    Kaufmann, Z; Szépfalusy, P

    1999-01-01

    One-dimensional maps exhibiting transient chaos and defined on two preimages of the unit interval [0,1] are investigated. It is shown that such maps have continuously many conditionally invariant measures $\\mu_{\\sigma}$ scaling at the fixed point at $x=0$ as $x^{\\sigma}$, but smooth elsewhere. Here $\\sigma$ should be smaller than a critical value $\\sigma_{c}$ that is related to the spectral properties of the Frobenius-Perron operator. The corresponding natural measures are proven to be entirely concentrated on the fixed point.

  6. Transient eddy current flow metering

    Science.gov (United States)

    Forbriger, J.; Stefani, F.

    2015-10-01

    Measuring local velocities or entire flow rates in liquid metals or semiconductor melts is a notorious problem in many industrial applications, including metal casting and silicon crystal growth. We present a new variant of an old technique which relies on the continuous tracking of a flow-advected transient eddy current that is induced by a pulsed external magnetic field. This calibration-free method is validated by applying it to the velocity of a spinning disk made of aluminum. First tests at a rig with a flow of liquid GaInSn are also presented.

  7. Modelación y simulación de disipadores de calor para procesadores de computadora en COMSOL Multiphysics Modeling and simulation of heat sinks for computer processors in COMSOL Multiphysics

    OpenAIRE

    2012-01-01

    En este estudio se analizó la transferencia de calor en tres disipadores de calor utilizados para enfriar los procesadores de computadoras de escritorio. El objetivo de estos disipadores es evitar el sobrecalentamiento de la unidad de procesamiento y la consecuente reducción de la vida útil del computador. Los disipadores de calor se modelaron usando COMSOL Multiphysics con las dimensiones reales de los dispositivos y la generación de calor se modeló con una fuente puntual. Luego se modificar...

  8. Respostas pós-colheita de abacaxi 'Pérola' no tratamento com calor e armazenagem refrigerada Postharvest behavior of 'Perola' pineapples to heat treatments cold storage

    Directory of Open Access Journals (Sweden)

    Rosilene Ferreira Souto

    2010-01-01

    Full Text Available Este trabalho teve como objetivo avaliar o efeito de diferentes temperaturas de armazenamento e do tratamento inicial a 40 ºC, por 24 horas, na preservação de abacaxis 'Pérola'. Os abacaxis foram colhidos no estádio de maturação "pintado", tratados com calor e foram mantidos sob condição de ambiente (25 ºC e 75-80% UR ou refrigerados durante 17 dias, a 8 ºC, ou 14 ºC. Após este período, foram transferidos para condição de ambiente, 25 ºC e 75-80% UR. As avaliações foram realizadas no início (0 dia e após 1; 5; 9; 13 ou 17 dias. Os frutos armazenados sob refrigeração foram transferidos para o ambiente e também foram avaliados aos 21, 25 ou 29 dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial (2x3x9, tendo-se os fatores, frutos tratados com calor ou não, três temperaturas de armazenamento e 9 épocas de avaliação. Os frutos foram avaliados quanto à perda de massa fresca, coloração externa, resistência da casca e da polpa, rendimento em polpa, além da intensidade respiratória. A perda de massa fresca e a resistência da casca e da polpa foram maiores nos frutos armazenados sob condição ambiente quando comparada à perda de massa e resistência dos abacaxis armazenados sob refrigeração, com variação na coloração da casca, de verde para amarela, com a evolução do tempo. Os abacaxis mantidos sob refrigeração a 8 ºC ou 14 ºC tiveram vida útil de 29 dias, enquanto os abacaxis mantidos a 25 ºC foram descartados após 17 dias. Abacaxis tratados com calor apresentaram a maior taxa respiratória, enquanto aqueles mantidos a 8 ºC apresentaram a menor atividade respiratória, tanto sob refrigeração como em condição ambiente.This work aimed to evaluate the effect of different temperature storage and a initial treatment at 40 ºC for 24 hours, to preserve 'Perola' pineapples. Pineapples were harvested at "pintado" ripening stage, heated and stored under

  9. Soluble Fermentable Dietary Fibre (Pectin Decreases Caloric Intake, Adiposity and Lipidaemia in High-Fat Diet-Induced Obese Rats.

    Directory of Open Access Journals (Sweden)

    Clare L Adam

    Full Text Available Consumption of a high fat diet promotes obesity and poor metabolic health, both of which may be improved by decreasing caloric intake. Satiety-inducing ingredients such as dietary fibre may be beneficial and this study investigates in diet-induced obese (DIO rats the effects of high or low fat diet with or without soluble fermentable fibre (pectin. In two independently replicated experiments, young adult male DIO rats that had been reared on high fat diet (HF; 45% energy from fat were given HF, low fat diet (LF; 10% energy from fat, HF with 10% w/w pectin (HF+P, or LF with 10% w/w pectin (LF+P ad libitum for 4 weeks (n = 8/group/experiment. Food intake, body weight, body composition (by magnetic resonance imaging, plasma hormones, and plasma and liver lipid concentrations were measured. Caloric intake and body weight gain were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Body fat mass increased in HF, was maintained in LF, but decreased significantly in LF+P and HF+P groups. Final plasma leptin, insulin, total cholesterol and triglycerides were lower, and plasma satiety hormone PYY concentrations were higher, in LF+P and HF+P than in LF and HF groups, respectively. Total fat and triglyceride concentrations in liver were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Therefore, the inclusion of soluble fibre in a high fat (or low fat diet promoted increased satiety and decreased caloric intake, weight gain, adiposity, lipidaemia, leptinaemia and insulinaemia. These data support the potential of fermentable dietary fibre for weight loss and improving metabolic health in obesity.

  10. Soluble Fermentable Dietary Fibre (Pectin) Decreases Caloric Intake, Adiposity and Lipidaemia in High-Fat Diet-Induced Obese Rats

    Science.gov (United States)

    Adam, Clare L.; Thomson, Lynn M.; Williams, Patricia A.; Ross, Alexander W.

    2015-01-01

    Consumption of a high fat diet promotes obesity and poor metabolic health, both of which may be improved by decreasing caloric intake. Satiety-inducing ingredients such as dietary fibre may be beneficial and this study investigates in diet-induced obese (DIO) rats the effects of high or low fat diet with or without soluble fermentable fibre (pectin). In two independently replicated experiments, young adult male DIO rats that had been reared on high fat diet (HF; 45% energy from fat) were given HF, low fat diet (LF; 10% energy from fat), HF with 10% w/w pectin (HF+P), or LF with 10% w/w pectin (LF+P) ad libitum for 4 weeks (n = 8/group/experiment). Food intake, body weight, body composition (by magnetic resonance imaging), plasma hormones, and plasma and liver lipid concentrations were measured. Caloric intake and body weight gain were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Body fat mass increased in HF, was maintained in LF, but decreased significantly in LF+P and HF+P groups. Final plasma leptin, insulin, total cholesterol and triglycerides were lower, and plasma satiety hormone PYY concentrations were higher, in LF+P and HF+P than in LF and HF groups, respectively. Total fat and triglyceride concentrations in liver were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Therefore, the inclusion of soluble fibre in a high fat (or low fat) diet promoted increased satiety and decreased caloric intake, weight gain, adiposity, lipidaemia, leptinaemia and insulinaemia. These data support the potential of fermentable dietary fibre for weight loss and improving metabolic health in obesity. PMID:26447990

  11. Soluble Fermentable Dietary Fibre (Pectin) Decreases Caloric Intake, Adiposity and Lipidaemia in High-Fat Diet-Induced Obese Rats.

    Science.gov (United States)

    Adam, Clare L; Thomson, Lynn M; Williams, Patricia A; Ross, Alexander W

    2015-01-01

    Consumption of a high fat diet promotes obesity and poor metabolic health, both of which may be improved by decreasing caloric intake. Satiety-inducing ingredients such as dietary fibre may be beneficial and this study investigates in diet-induced obese (DIO) rats the effects of high or low fat diet with or without soluble fermentable fibre (pectin). In two independently replicated experiments, young adult male DIO rats that had been reared on high fat diet (HF; 45% energy from fat) were given HF, low fat diet (LF; 10% energy from fat), HF with 10% w/w pectin (HF+P), or LF with 10% w/w pectin (LF+P) ad libitum for 4 weeks (n = 8/group/experiment). Food intake, body weight, body composition (by magnetic resonance imaging), plasma hormones, and plasma and liver lipid concentrations were measured. Caloric intake and body weight gain were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Body fat mass increased in HF, was maintained in LF, but decreased significantly in LF+P and HF+P groups. Final plasma leptin, insulin, total cholesterol and triglycerides were lower, and plasma satiety hormone PYY concentrations were higher, in LF+P and HF+P than in LF and HF groups, respectively. Total fat and triglyceride concentrations in liver were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Therefore, the inclusion of soluble fibre in a high fat (or low fat) diet promoted increased satiety and decreased caloric intake, weight gain, adiposity, lipidaemia, leptinaemia and insulinaemia. These data support the potential of fermentable dietary fibre for weight loss and improving metabolic health in obesity.

  12. Continuous versus bolus tube feeds: Does the modality affect glycemic variability, tube feeding volume, caloric intake, or insulin utilization?

    Science.gov (United States)

    Evans, David C; Forbes, Rachel; Jones, Christian; Cotterman, Robert; Njoku, Chinedu; Thongrong, Cattleya; Tulman, David; Bergese, Sergio D; Thomas, Sheela; Papadimos, Thomas J; Stawicki, Stanislaw P

    2016-01-01

    Introduction: Enteral nutrition (EN) is very important to optimizing outcomes in critical illness. Debate exists regarding the best strategy for enteral tube feeding (TF), with concerns that bolus TF (BTF) may increase glycemic variability (GV) but result in fewer nutritional interruptions than continuous TF (CTF). This study examines if there is a difference in GV, insulin usage, TF volume, and caloric delivery among intensive care patients receiving BTF versus CTF. We hypothesize that there are no significant differences between CTF and BTF when comparing the above parameters. Materials and Methods: Prospective, randomized pilot study of critically ill adult patients undergoing percutaneous endoscopic gastrostomy (PEG) placement for EN was performed between March 1, 2012 and May 15, 2014. Patients were randomized to BTF or CTF. Glucose values, insulin use, TF volume, and calories administered were recorded. Data were organized into 12-h epochs for statistical analyses and GV determination. In addition, time to ≥80% nutritional delivery goal, demographics, Acute Physiology and Chronic Health Evaluation II scores, and TF interruptions were examined. When performing BTF versus CTF assessments, continuous parameters were compared using Mann–Whitney U-test or repeated measures t-test, as appropriate. Categorical data were analyzed using Fisher's exact test. Results: No significant demographic or physiologic differences between the CTF (n = 24) and BTF (n = 26) groups were seen. The immediate post-PEG 12-h epoch showed significantly lower GV and median TF volume for patients in the CTF group. All subsequent epochs (up to 18 days post-PEG) showed no differences in GV, insulin use, TF volume, or caloric intake. Insulin use for both groups increased when comparing the first 24 h post-PEG values to measurements from day 8. There were no differences in TF interruptions, time to ≥80% nutritional delivery goal, or hypoglycemic episodes. Conclusions: This study

  13. Time restricted feeding without reducing caloric intake prevents metabolic diseases in mice fed a high fat diet

    OpenAIRE

    Hatori, Megumi; Vollmers, Christopher; Zarrinpar, Amir; DiTacchio, Luciano; Bushong, Eric A.; Gill, Shubhroz; Leblanc, Mathias; Chaix, Amandine; Joens, Matthew; Fitzpatrick, James A. J.; Ellisman, Mark H.; Panda, Satchidananda

    2012-01-01

    While diet-induced obesity has been exclusively attributed to increased caloric intake from fat, animals fed high fat diet (HFD) ad libitum (ad lib) eat frequently throughout day and night disrupting the normal feeding cycle. To test whether obesity and metabolic diseases result from HFD or disruption of metabolic cycles, we subjected mice to either ad lib or time restricted feeding (tRF) of a HFD for 8 h/day. Mice under tRF consume equivalent calories from HFD as those with ad lib access, ye...

  14. Estudio experimental del aprovechamiento del calor residual de un MACI para generar hidrógeno catalíticamente

    OpenAIRE

    Rejas García, Albert

    2014-01-01

    A lo largo de este proyecto se realiza el estudio de la posibilidad de la utilización de energía residual, concretamente el calor disipado por los gases de escape de un motor de combustión, para el reformado catalítico de hidrógeno. Es decir, la obtención de un vector energético a partir de energía no aprovechada, lo que significa un aumento de la eficiencia del sistema. Para realizar el reformado se han valorado diferentes catalizadores: uno de cobalto y uno de rodio-paladio, así...

  15. Estudio de penetración de calor en una conserva de camarón envasada en empaque flexible

    OpenAIRE

    Vasquez Veliz, Carlos Javier

    2008-01-01

    En el presente estudio se determinaron los parámetros de proceso térmico para la obtención de una conserva de camarón envasada en un empaque flexible de cuatro capas y de uso unipersonal. Se realizaron pruebas experimentales para determinar la formulación del líquido de cobertura y las condiciones de envasado y sellado del producto. En planta piloto se procedió a realizar un estudio de penetración de calor; para definir mediante el método matemático de Stumbo los parámetros de proceso (...

  16. Transferencia de calor durante la congelación, el almacenamiento y la descongelación de alimentos

    OpenAIRE

    Salvadori, Viviana Olga

    1994-01-01

    En el presente trabajo se estudian distintos aspectos relacionados con la congelación y el almacenamiento de productos congelados, con los siguientes objetivos: - Optimizar el diseño de sistemas para la congelación o almacenamiento de alimentos a través de un mejor conocimiento de los fenómenos de transferencia de calor que tienen lugar en los mismos. Esto involucra un adecuado dimensionamiento de los equipos con el consiguiente ahorro en los costos de inversión. - Desar...

  17. Modelo para estudios de estabilidad de calderas de recuperación de calor (HRSG) y turbina de vapor

    OpenAIRE

    Corasaniti, Víctor Fabián; Agüero, Jorge Luis; Bianchi Lastra, Raúl E.

    2013-01-01

    En este trabajo se presenta la determinación y validación de los parámetros de un modelo digital para estudios de estabilidad que representa dos Calderas de Recuperación de Calor (HRSG, del inglés Heat Recovery Steam Generator), conjuntamente con la Turbina de Vapor a la cual suministran vapor. Los 2 HRSG producen vapor a partir de los gases de escape de 2 turbinas de gas. El modelo de simulación se implementa en el programa PSS/E (Power System Simulator), programa usado para estudios de est...

  18. Análisis diferencial de las condiciones de transporte de calor en un colector solar de placa plana

    OpenAIRE

    José Eduardo Flores-Ortega; Román Bravo-Cadena; Ignacio Carvajal-Mariscal

    2013-01-01

    Este trabajo expone el análisis de las condiciones de transporte de calor en un colector solar de placa plana, el colector calienta aire para emplearlo más adelante, como puede ser en la deshidratación de diferentes perecederos, entre otros. El método empleado para la transferencia térmica es por convección natural. Se desarrolla el modelado matemático para obtener las ecuaciones de transporte, identificándose las variables de posición, velocidad y momento. Se propone una solución usando la t...

  19. Chronic Caloric Restriction and Exercise Improve Metabolic Conditions of Dietary-Induced Obese Mice in Autophagy Correlated Manner without Involving AMPK

    Directory of Open Access Journals (Sweden)

    Mingxia Cui

    2013-01-01

    Full Text Available Aim. To investigate the role of AMPK activation and autophagy in mediating the beneficial effects of exercise and caloric restriction in obesity. Methods. Dietary-induced obesity mice were made and divided into 5 groups; one additional group of normal mice serves as control. Mice in each group received different combinations of interventions including low fat diet, caloric restriction, and exercise. Then their metabolic conditions were assessed by measuring serum glucose and insulin, serum lipids, and liver function. AMPK phosphorylation and autophagy activity were detected by western blotting. Results. Obese mice models were successfully induced by high fat diet. Caloric restriction consistently improved the metabolic conditions of the obese mice, and the effects are more prominent than the mice that received only exercise. Also, caloric restriction, exercise, and low fat diet showed a synergistic effect in the improvement of metabolic conditions. Western blotting results showed that this improvement was not related with the activation of AMPK in liver, skeletal muscle, or heart but correlates well with the autophagy activity. Conclusion. Caloric restriction has more prominent beneficial effects than exercise in dietary-induced obese mice. These effects are correlated with the autophagy activity and may be independent of AMPK activation.

  20. Evolutionary pressure on mitochondrial cytochrome b is consistent with a role of CytbI7T affecting longevity during caloric restriction.

    Directory of Open Access Journals (Sweden)

    Wesley A Beckstead

    Full Text Available BACKGROUND: Metabolism of energy nutrients by the mitochondrial electron transport chain (ETC is implicated in the aging process. Polymorphisms in core ETC proteins may have an effect on longevity. Here we investigate the cytochrome b (cytb polymorphism at amino acid 7 (cytbI7T that distinguishes human mitochondrial haplogroup H from haplogroup U. PRINCIPAL FINDINGS: We compared longevity of individuals in these two haplogroups during historical extremes of caloric intake. Haplogroup H exhibits significantly increased longevity during historical caloric restriction compared to haplogroup U (p = 0.02 while during caloric abundance they are not different. The historical effects of natural selection on the cytb protein were estimated with the software TreeSAAP using a phylogenetic reconstruction for 107 mammal taxa from all major mammalian lineages using 13 complete protein-coding mitochondrial gene sequences. With this framework, we compared the biochemical shifts produced by cytbI7T with historical evolutionary pressure on and near this polymorphic site throughout mammalian evolution to characterize the role cytbI7T had on the ETC during times of restricted caloric intake. SIGNIFICANCE: Our results suggest the relationship between caloric restriction and increased longevity in human mitochondrial haplogroup H is determined by cytbI7T which likely enhances the ability of water to replenish the Q(i binding site and decreases the time ubisemiquinone is at the Q(o site, resulting in a decrease in the average production rate of radical oxygen species (ROS.

  1. Chemotherapy for isolated locoregional recurrence of breast cancer (CALOR): a randomised trial.

    Science.gov (United States)

    Aebi, Stefan; Gelber, Shari; Anderson, Stewart J; Láng, István; Robidoux, André; Martín, Miguel; Nortier, Johan W R; Paterson, Alexander H G; Rimawi, Mothaffar F; Cañada, José Manuel Baena; Thürlimann, Beat; Murray, Elizabeth; Mamounas, Eleftherios P; Geyer, Charles E; Price, Karen N; Coates, Alan S; Gelber, Richard D; Rastogi, Priya; Wolmark, Norman; Wapnir, Irene L

    2014-02-01

    Patients with isolated locoregional recurrences (ILRR) of breast cancer have a high risk of distant metastasis and death from breast cancer. We aimed to establish whether adjuvant chemotherapy improves the outcome of such patients. The CALOR trial was a pragmatic, open-label, randomised trial that accrued patients with histologically proven and completely excised ILRR after unilateral breast cancer who had undergone a mastectomy or lumpectomy with clear surgical margins. Eligible patients were enrolled from hospitals worldwide and were centrally randomised (1:1) to chemotherapy (type selected by the investigator; multidrug for at least four courses recommended) or no chemotherapy, using permuted blocks, and stratified by previous chemotherapy, oestrogen-receptor and progesterone-receptor status, and location of ILRR. Patients with oestrogen-receptor-positive ILRR received adjuvant endocrine therapy, radiation therapy was mandated for patients with microscopically involved surgical margins, and anti-HER2 therapy was optional. The primary endpoint was disease-free survival. All analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00074152. From Aug 22, 2003, to Jan 31, 2010, 85 patients were randomly assigned to receive chemotherapy and 77 were assigned to no chemotherapy. At a median follow-up of 4·9 years (IQR 3·6-6 ·0), 24 (28%) patients had disease-free survival events in the chemotherapy group compared with 34 (44%) in the no chemotherapy group. 5-year disease-free survival was 69% (95% CI 56-79) with chemotherapy versus 57% (44-67) without chemotherapy (hazard ratio 0·59 [95% CI 0·35-0·99]; p=0·046). Adjuvant chemotherapy was significantly more effective for women with oestrogen-receptor-negative ILRR (pinteraction=0·046), but analyses of disease-free survival according to the oestrogen-receptor status of the primary tumour were not statistically significant (pinteraction=0·43). Of the 81 patients who

  2. Chemotherapy for Isolated Locoregional Recurrence of Breast Cancer: The CALOR Randomised Trial

    Science.gov (United States)

    Aebi, Stefan; Gelber, Shari; Anderson, Stewart J.; Láng, István; Robidoux, André; Martín, Miguel; Nortier, Johan W.R.; Paterson, Alexander H.G.; Rimawi, Mothaffar F.; Cañada, José Manuel Baena; Thürlimann, Beat; Murray, Elizabeth; Mamounas, Eleftherios P.; Geyer, Charles E.; Price, Karen N.; Coates, Alan S.; Gelber, Richard D.; Rastogi, Priya; Wolmark, Norman; Wapnir, Irene L.

    2014-01-01

    BACKGROUND Patients with isolated locoregional recurrences (ILRR) of breast cancer have a high risk of distant metastasis and death from breast cancer. We investigated adjuvant chemotherapy for such patients in a randomised clinical trial. METHODS The CALOR trial (clinicaltrials.gov NCT00074152) accrued patients 2003-2010. The 162 patients with resected ILRR were centrally randomised using permuted blocks and stratified by prior chemotherapy, ER/PgR status, and location of ILRR. Eighty-five were allocated to chemotherapy (type selected by the investigator; multidrug for at least four courses recommended) and 77 to no chemotherapy. Patients with oestrogen receptor-positive ILRR received adjuvant endocrine therapy; radiation therapy was mandated for patients with microscopically involved surgical margins, and anti-HER2 therapy was optional. The primary endpoint was disease-free survival (DFS). All analyses were by intention to treat. FINDINGS At a median follow up of 4·9 (IQR 3.6,6.0) years we observed 24 DFS events and nine deaths in the chemotherapy group compared with 34 DFS events and 21 deaths in the no chemotherapy group. Five-year DFS was 69% vs. 57%, (hazard ratio for chemotherapy versus no chemotherapy, 0·59; 95% confidence interval 0·35 to 0·99; P=0·046) and five-year overall survival was 88% vs. 76%, (hazard ratio, 0·41; 95% CI, 0·19 to 0·89; P=0·02). Adjuvant chemotherapy was significantly more effective for women with oestrogen receptor-negative disease measured in the recurrence (interaction P=0·04), but analyses of DFS based on the oestrogen receptor status of the primary tumour were not statistically significant (interaction P=0·43). Among the 85 patients who received standard chemotherapy, 12 reported SAEs. INTERPRETATION Adjuvant chemotherapy should be recommended for patients with completely resected isolated locoregional recurrences of breast cancer, especially if the recurrence is oestrogen receptor negative. FUNDING Public Service

  3. Glycemic effects of intensive caloric restriction and isocaloric refeeding in noninsulin-dependent diabetes mellitus.

    Science.gov (United States)

    Henry, R R; Scheaffer, L; Olefsky, J M

    1985-11-01

    To assess the effects of very low caloric (VLC) diets on glucose homeostasis in noninsulin-dependent diabetes mellitus, 30 obese subjects with NIDDM were studied for 40 days while eating a 330 Cal/day diet, with a subgroup of 12 subjects further evaluated during 40 days of refeeding. All subjects successfully lost weight, with an average weight loss of 4.6 +/- 0.2 kg (+/- SEM) after 10 days, 7.1 +/- 0.3 kg after 20 days, and 10.5 +/- 0.4 kg after 40 days of VLC diet therapy. Thus, weight loss was steady and progressive throughout the diet period. In contrast, the majority (87%) of the reduction in mean fasting plasma glucose (FPG) levels (297 +/- 13 to 158 +/- 10 mg/dl; P less than 0.001) occurred after 10 days of VLC diet therapy, with a further reduction in glucose levels to 138 +/- 9 mg/dl on day 40. The FPG response measured after 10 days of VLC diet was unrelated to the degree of obesity, rate or extent of weight loss, or prevailing insulin levels, but did correlate significantly with the initial FPG level (r = 0.37; P less than 0.05) and duration of diabetes (r = 0.42; P less than 0.05). After discontinuation of the VLC diet and refeeding of an isocaloric (weight maintenance) diet in 12 subjects, a variable increase in the FPG occurred, with an average increase of 80% after 40 days of refeeding. However, the mean FPG level after 40 days of refeeding was still markedly lower than that before VLC diet therapy (254 +/- 20 vs. 167 +/- 14 mg/dl; P less than 0.02) despite withdrawal of antidiabetic medication in all subjects. The basal hepatic glucose output (HGO) fell rapidly from 149 +/- 13 to 81 +/- 5 mg/M2 X min (P less than 0.001) after 10 days of VLC diet and rose from 67 +/- 4 to 88 +/- 7 mg/M2 X min (P less than 0.001) after 10 days of refeeding. Basal HGO demonstrated a highly significant positive correlation with FPG levels (r = 0.89; P less than 0.001) before and during both VLC diet therapy and refeeding. A significant correlation was also found between

  4. Transient effects in Herschel/PACS spectroscopy

    Science.gov (United States)

    Fadda, Dario; Jacobson, Jeffery D.; Appleton, Philip N.

    2016-10-01

    Context. The Ge:Ga detectors used in the PACS spectrograph onboard the Herschel space telescope react to changes of the incident flux with a certain delay. This generates transient effects on the resulting signal which can be important and last for up to an hour. Aims: The paper presents a study of the effects of transients on the detected signal and proposes methods to mitigate them especially in the case of the unchopped mode. Methods: Since transients can arise from a variety of causes, we classified them in three main categories: transients caused by sudden variations of the continuum due to the observational mode used; transients caused by cosmic ray impacts on the detectors; transients caused by a continuous smooth variation of the continuum during a wavelength scan. We propose a method to disentangle these effects and treat them separately. In particular, we show that a linear combination of three exponential functions is needed to fit the response variation of the detectors during a transient. An algorithm to detect, fit, and correct transient effects is presented. Results: The solution proposed to correct the signal for the effects of transients substantially improves the quality of the final reduction with respect to the standard methods used for archival reduction in the cases where transient effects are most pronounced. Conclusions: The programs developed to implement the corrections are offered through two new interactive data reduction pipelines in the latest releases of the Herschel Interactive Processing Environment.

  5. Transient Science from Diverse Surveys

    Science.gov (United States)

    Mahabal, A.; Crichton, D.; Djorgovski, S. G.; Donalek, C.; Drake, A.; Graham, M.; Law, E.

    2016-12-01

    Over the last several years we have moved closer to being able to make digital movies of the non-static sky with wide-field synoptic telescopes operating at a variety of depths, resolutions, and wavelengths. For optimal combined use of these datasets, it is crucial that they speak and understand the same language and are thus interoperable. Initial steps towards such interoperability (e.g. the footprint service) were taken during the two five-year Virtual Observatory projects viz. National Virtual Observatory (NVO), and later Virtual Astronomical Observatory (VAO). Now with far bigger datasets and in an era of resource excess thanks to the cloud-based workflows, we show how the movement of data and of resources is required - rather than just one or the other - to combine diverse datasets for applications such as real-time astronomical transient characterization. Taking the specific example of ElectroMagnetic (EM) follow-up of Gravitational Wave events and EM transients (such as CRTS but also other optical and non-optical surveys), we discuss the requirements for rapid and flexible response. We show how the same methodology is applicable to Earth Science data with its datasets differing in spatial and temporal resolution as well as differing time-spans.

  6. Special issue on transient plasmas

    Science.gov (United States)

    Bailey, James; Hoarty, David; Mancini, Roberto; Yoneda, Hitoki

    2015-11-01

    This special issue of Journal of Physics B: Atomic, Molecular and Optical Physics is dedicated to the "spectroscopy of transient plasmas" covering plasma conditions produced by a range of pulsed laboratory sources including short and long pulse lasers, pulsed power devices, and free electron lasers (FELs). The full range of plasma spectroscopy up to high energy bremsstrahlung radiation, including line broadening analysis for application to data recorded with the ChemCam instrument on the Mars Science Laboratory rover Curiosity, is covered. This issue is timely as advances in optical lasers and x-ray FELs (XFEL) are enabling transient plasma to be probed at higher energies and shorter durations than ever before. New XFEL facilities being commissioned in Europe and Asia are adding to those operating in the US and Japan and the ELI high power laser project in Europe, due to open this year, will provide short pulse lasers of unprecedented power. This special issue represents a snapshot of the theoretical and experimental research in dense plasmas, electron kinetics, laser-induced breakdown spectroscopy of low temperature plasmas, inertial confinement fusion and non-equilibrium atomic physics using spectroscopy to diagnose plasmas produced by optical lasers, XFELs and pulsed-power machines.

  7. The Zwicky Transient Facility Camera

    Science.gov (United States)

    Dekany, Richard; Smith, Roger M.; Belicki, Justin; Delacroix, Alexandre; Duggan, Gina; Feeney, Michael; Hale, David; Kaye, Stephen; Milburn, Jennifer; Murphy, Patrick; Porter, Michael; Reiley, Daniel J.; Riddle, Reed L.; Rodriguez, Hector; Bellm, Eric C.

    2016-08-01

    The Zwicky Transient Facility Camera (ZTFC) is a key element of the ZTF Observing System, the integrated system of optoelectromechanical instrumentation tasked to acquire the wide-field, high-cadence time-domain astronomical data at the heart of the Zwicky Transient Facility. The ZTFC consists of a compact cryostat with large vacuum window protecting a mosaic of 16 large, wafer-scale science CCDs and 4 smaller guide/focus CCDs, a sophisticated vacuum interface board which carries data as electrical signals out of the cryostat, an electromechanical window frame for securing externally inserted optical filter selections, and associated cryo-thermal/vacuum system support elements. The ZTFC provides an instantaneous 47 deg2 field of view, limited by primary mirror vignetting in its Schmidt telescope prime focus configuration. We report here on the design and performance of the ZTF CCD camera cryostat and report results from extensive Joule-Thompson cryocooler tests that may be of broad interest to the instrumentation community.

  8. Transient stability and emergency control

    Institute of Scientific and Technical Information of China (English)

    ZHANG XueMin; MEI ShengWei; WU ShengYu

    2009-01-01

    Comparability of emergency control strategies with different instability modes is the key issue to de-cide which control strategy to be implemented. This paper considers that the essential factor causing instability should be used to form a unified standard to assess the effectiveness of control strategies with different instability modes. Thus a switching control stabilization principle was proposed based on elimination of the unbalanced energy between mechanical and electrical energies of generator sets. Along this way, the difficulty of seeking a Lyapunov function was circumvented. According to the prin-ciple, an emergency control algorithm framework was established to handle transient stability as-sessment, control location selection and control amount evaluation. Within the framework, this paper studied instability mode transition, then proposed an algorithm based on prediction function and a new approach to normalized stability margin stemmed from static EEAC method, which can increase com-parability of various control locations. The simulations on the New-England System verified the pro-posed emergency control method for stabilizing transient stability.

  9. The two C-terminal tyrosines stabilize occluded Na/K pump conformations containing Na or K ions.

    Science.gov (United States)

    Vedovato, Natascia; Gadsby, David C

    2010-07-01

    Interactions of the three transported Na ions with the Na/K pump remain incompletely understood. Na/K pump crystal structures show that the extended C terminus of the Na,K-adenosine triphosphatase (ATPase) alpha subunit directly contacts transmembrane helices. Deletion of the last five residues (KETYY in almost all Na/K pumps) markedly lowered the apparent affinity for Na activation of pump phosphorylation from ATP, a reflection of cytoplasmic Na affinity for forming the occluded E1P(Na3) conformation. ATPase assays further suggested that C-terminal truncations also interfere with low affinity Na interactions, which are attributable to extracellular effects. Because extracellular Na ions traverse part of the membrane's electric field to reach their binding sites in the Na/K pump, their movements generate currents that can be monitored with high resolution. We report here electrical measurements to examine how Na/K pump interactions with extracellular Na ions are influenced by C-terminal truncations. We deleted the last two (YY) or five (KESYY) residues in Xenopus laevis alpha1 Na/K pumps made ouabain resistant by either of two kinds of point mutations and measured their currents as 10-mM ouabain-sensitive currents in Xenopus oocytes after silencing endogenous Xenopus Na/K pumps with 1 microM ouabain. We found the low affinity inhibitory influence of extracellular Na on outward Na/K pump current at negative voltages to be impaired in all of the C-terminally truncated pumps. Correspondingly, voltage jump-induced transient charge movements that reflect pump interactions with extracellular Na ions were strongly shifted to more negative potentials; this signals a several-fold reduction of the apparent affinity for extracellular Na in the truncated pumps. Parallel lowering of Na affinity on both sides of the membrane argues that the C-terminal contacts provide important stabilization of the occluded E1P(Na3) conformation, regardless of the route of Na ion entry into the

  10. Uso de transdutores de fluxo de calor no estudo da transferência de calor em alimentos embalados The use of heat flux transducers to study heat transfer in canned foods

    Directory of Open Access Journals (Sweden)

    B. Carciofi

    2002-12-01

    Full Text Available A densidade de fluxo de calor que atravessa uma superfície é classicamente determinada mediante a medição das temperaturas apropriadas e da aplicação da Lei de Fourier. Uma alternativa a esse procedimento é a utilização de transdutores de fluxo de calor, os quais geram um sinal elétrico proporcional ao fluxo térmico que os atravessa. Neste trabalho, processos de aquecimento e de resfriamento de alimentos foram estudados em laboratório, utilizando-se um recipiente de vidro cilíndrico para simular uma embalagem. Dois transdutores de fluxo de calor a gradiente tangencial foram previamente instalados no recipiente, revestindo completamente a superfície lateral do mesmo. O recipiente contendo a amostra foi inserido em banho de água circulante à temperatura constante. Os sinais fornecidos pelos transdutores e por termopares inseridos no interior do recipiente foram registrados por um sistema de aquisição de dados computadorizado. Os resultados obtidos com o uso dos transdutores foram comparados com aqueles obtidos através de balanços de energia realizados a partir dos dados experimentais de evolução temporal das temperaturas da amostra junto à superfície interna da embalagem e no centro da mesma. A comparação mostrou que os transdutores de fluxo de calor a gradiente tangencial puderam determinar os fluxos de calor, com tempo de resposta característico dos termopares. Os resultados apresentados mostraram a viabilidade de utilização desses fluxímetros no estudo não destrutivo e não invasivo dos processos de aquecimento e de resfriamento de alimentos, fornecendo informações complementares àquelas obtidas pelo uso de termopares instalados no interior da embalagem.Heat flux determination in thermal processes is classically carried out by appropriate temperature measurements and the application of the Fourier Law. An alternative to this procedure is to determine the heat flux that crosses a surface using heat flux

  11. Voltage dependence of the Na-K pump.

    Science.gov (United States)

    De Weer, P; Gadsby, D C; Rakowski, R F

    1988-01-01

    Present evidence demonstrates that the Na-K pump rate is voltage dependent, whereas early work was largely inconclusive. The I-V relationship has a positive slope over a wide voltage range, and the existence of a negative slope region is now doubtful. Monotonic voltage dependence is consistent with the reaction cycle containing a single voltage-dependent step. Recent measurements suggest that this voltage-dependent step occurs during Na translocation and may be deocclusion of Na+. In addition, two results suggest that K translocation is voltage insensitive: (a) large positive potentials appear to have no influence on Rb-Rb exchange or associated conformational transitions; and (b) transient currents associated with Na translocation appear to involve movement of a single charge, which is sufficient for a 3Na-2K cycle. The simplest interpretation is that the pump's cation binding sites supply two negative charges. Pre-steady-state measurements demonstrate that Na translocation precedes the pump cycle's rate-limiting step, presumably K translocation. But, because K translocation seems voltage insensitive, the voltage dependence of the steady-state pump rate probably reflects that of the concentration of the intermediate entering this slow step. Further pump current and flux data (both transient and steady-state), carefully determined over a range of conditions, should increase our understanding of the voltage-dependent step(s) in the Na-K pump cycle.

  12. High-Caloric and Chocolate Stimuli Processing in Healthy Humans: An Integration of Functional Imaging and Electrophysiological Findings

    Science.gov (United States)

    Asmaro, Deyar; Liotti, Mario

    2014-01-01

    There has been a great deal of interest in understanding how the human brain processes appetitive food cues, and knowing how such cues elicit craving responses is particularly relevant when current eating behavior trends within Westernized societies are considered. One substance that holds a special place with regard to food preference is chocolate, and studies that used functional magnetic resonance imaging (fMRI) and event-related potentials (ERPs) have identified neural regions and electrical signatures that are elicited by chocolate cue presentations. This review will examine fMRI and ERP findings from studies that used high-caloric food and chocolate cues as stimuli, with a focus on responses observed in samples of healthy participants, as opposed to those with eating-related pathology. The utility of using high-caloric and chocolate stimuli as a means of understanding the human reward system will also be highlighted, as these findings may be particularly important for understanding processes related to pathological overeating and addiction to illicit substances. Finally, research from our own lab that focused on chocolate stimulus processing in chocolate cravers and non-cravers will be discussed, as the approach used may help bridge fMRI and ERP findings so that a more complete understanding of appetitive stimulus processing in the temporal and spatial domains may be established. PMID:24434747

  13. High-Caloric and Chocolate Stimuli Processing in Healthy Humans: An Integration of Functional Imaging and Electrophysiological Findings

    Directory of Open Access Journals (Sweden)

    Deyar Asmaro

    2014-01-01

    Full Text Available There has been a great deal of interest in understanding how the human brain processes appetitive food cues, and knowing how such cues elicit craving responses is particularly relevant when current eating behavior trends within Westernized societies are considered. One substance that holds a special place with regard to food preference is chocolate, and studies that used functional magnetic resonance imaging (fMRI and event-related potentials (ERPs have identified neural regions and electrical signatures that are elicited by chocolate cue presentations. This review will examine fMRI and ERP findings from studies that used high-caloric food and chocolate cues as stimuli, with a focus on responses observed in samples of healthy participants, as opposed to those with eating-related pathology. The utility of using high-caloric and chocolate stimuli as a means of understanding the human reward system will also be highlighted, as these findings may be particularly important for understanding processes related to pathological overeating and addiction to illicit substances. Finally, research from our own lab that focused on chocolate stimulus processing in chocolate cravers and non-cravers will be discussed, as the approach used may help bridge fMRI and ERP findings so that a more complete understanding of appetitive stimulus processing in the temporal and spatial domains may be established.

  14. Caloric restriction maintains OX40 agonist-mediated tumor immunity and CD4 T cell priming during aging.

    Science.gov (United States)

    Farazi, Michelle; Nguyen, Justine; Goldufsky, Josef; Linnane, Stephanie; Lukaesko, Lisa; Weinberg, Andrew D; Ruby, Carl E

    2014-06-01

    Immune responses wane during aging, posing challenges to the potential effectiveness of cancer immunotherapies. We previously demonstrated that in the context of a promising immunotherapeutic, OX40 agonist (αOX40), older animals exhibited impaired anti-tumor immune responses and diminished CD4 T cell effector differentiation. In this study, we hypothesized that tumor immune responses could be maintained during aging through caloric restriction (CR) or dietary supplementation with resveratrol (RES), a CR mimetic. Mice were placed on either a calorically restricted diet or a RES-formulated diet starting between 4 and 6 months of age and continued until mice reached 12 months of age. Tumor immune responses were assessed after challenging with either sarcoma or breast tumor cells followed by αOX40 treatment. Our results show that CR, but not RES, maintained OX40-mediated anti-tumor immunity. In addition, CR fully sustained antigen-specific CD4 T cell priming in aged hosts (12 months old), whereas tumor-specific CD8 T cell priming was not fully maintained compared to young reference animals (2 months old). Thus, CR appears to maintain immunological fitness of the CD4 T cell priming environment during aging, which is critical for optimal OX40-mediated responses.

  15. Caloric Vestibular Stimulation Reduces Pain and Somatoparaphrenia in a Severe Chronic Central Post-Stroke Pain Patient: A Case Study.

    Science.gov (United States)

    Spitoni, Grazia Fernanda; Pireddu, Giorgio; Galati, Gaspare; Sulpizio, Valentina; Paolucci, Stefano; Pizzamiglio, Luigi

    2016-01-01

    Central post-stroke pain is a neuropathic syndrome characterized by intolerable contralesional pain and, in rare cases, somatic delusions. To date, there is limited evidence for the effective treatments of this disease. Here we used caloric vestibular stimulation to reduce pain and somatoparaphrenia in a 57-year-old woman suffering from central post-stroke pain. Resting-state functional magnetic resonance imaging was used to assess the neurological effects of this treatment. Following vestibular stimulation we observed impressive improvements in motor skills, pain, and somatic delusions. In the functional connectivity study before the vestibular stimulation, we observed differences in the patient's left thalamus functional connectivity, with respect to the thalamus connectivity of a control group (N = 20), in the bilateral cingulate cortex and left insula. After the caloric stimulation, the left thalamus functional connectivity with these regions, which are known to be involved in the cortical response to pain, disappeared as in the control group. The beneficial use of vestibular stimulation in the reduction of pain and somatic delusion in a CPSP patient is now documented by behavioral and imaging data. This evidence can be applied to theoretical models of pain and body delusions.

  16. Modelo matemático de la transferencia de calor para predecir el perfil de durezas en probetas Jominy

    Directory of Open Access Journals (Sweden)

    López, E.

    2013-04-01

    Full Text Available The heat transfer coefficient was estimated at the bottom surface at Jominy bar end quench specimen by solution of the heat inverse conduction problem. A mathematical model based on the finite-difference method was developed to predict thermal paths and volume fraction of transformed phases. The mathematical model was codified in the commercial package Microsoft Visual Basic v. 6. The calculated thermal path and final phase distribution were used to evaluate the hardness distribution along the AISI 4140 Jominy bar.En el presente trabajo se estimó el coeficiente de transferencia de calor en la superficie que se encuentra en contacto con el chorro de agua en la probeta Jominy mediante la solución del problema inverso de conducción de calor. Con el objetivo de predecir los perfiles térmicos y las fracciones de fase transformadas se formuló un modelo matemático con el método de diferencias finitas y se codificó en el software comercial Microsoft Visual Basic v. 6. Los perfiles térmicos y las fracciones de fase calculadas se utilizaron para predecir el perfil de durezas en una probeta Jominy de acero AISI 4140 mediante el uso de correlaciones empíricas.

  17. Modelo matemático para la descripción de la transferencia de calor para tierra vertida

    Directory of Open Access Journals (Sweden)

    Edgardo Jonathan Suárez-Domínguez

    2014-01-01

    Full Text Available La arquitectura de tierra implica procesos constructivos sustentables ya que utiliza materiales vernáculos duraderos cuyos residuos son de bajo impacto al ambiente. La tierra vertida es una técnica a partir de la cual pueden tenerse muros resistentes dentro de la edificación de viviendas pero cuyas propiedades han sido poco evaluadas y representadas a partir de modelos. La transferencia de calor es una de las características más importantes cuando se edifica en zonas calurosas pues implica ciertos niveles de confort para los usuarios. El presente trabajo propone un modelo para determinar la difusividad térmica de tierra vertida con uso potencial para otras determinaciones a diversas temperaturas, algunas implicaciones también son presentadas. Se encontró que el coeficiente de difusividad térmica de muestras de tierra vertida fue de   4.319  10 8 m 2 s 1 , mientras que su calor específico es de 1.1030 kJkg-1K 1 .

  18. Searching the conditions for a table-like shape of the magnetic entropy in magneto-caloric materials

    Energy Technology Data Exchange (ETDEWEB)

    Álvarez, Pablo, E-mail: pablo.alvarez@ehu.es [Departamento de Electricidad y Electrónica, Universidad del País Vasco (UPV/EHU), 48940 Leioa (Spain); Departamento de Física, Universidad de Oviedo, c/ Calvo Sotelo, s/n, 33007 Oviedo (Spain); Gorria, Pedro, E-mail: pgorria@uniovi.es [Departamento de Física, Universidad de Oviedo, c/ Calvo Sotelo, s/n, 33007 Oviedo (Spain); Sánchez Llamazares, José L. [División de Materiales Avanzados, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la presa San José 2055, CP 78216 San Luis Potosí (Mexico); Blanco, Jesús A. [Departamento de Física, Universidad de Oviedo, c/ Calvo Sotelo, s/n, 33007 Oviedo (Spain)

    2013-08-15

    Highlights: •The magnetic entropy change for two-ribbon (amorphous) composite materials is investigated. •The conditions to obtain a table-like shape of the magnetic entropy change are specified. •We give the essential ingredients to maximize the effective refrigerant capacity and the efficiency. •Our findings could be used in other magneto-caloric materials to tune the temperature range for the table-like behavior. -- Abstract: We show a systematic study of the magneto-caloric response carried out on a series of FeZrB(Cu) amorphous ribbons with different Curie temperature values in the 210–320 K interval. The main aim of the work is to investigate the conditions to obtain, from the isothermal magnetic entropy change vs. temperature curves, ΔS{sub M}(T), a table-like behavior of the entropy using two-ribbon composites. Even though the maximum value of ΔS{sub M} for the composite is lower than those of the single components, the existence of a table-like behavior maximizes the effective refrigerant capacity, reaching values around 80 J/kg for an applied magnetic field change of 2 T. Furthermore, we discuss how the temperature range for such a table-like behavior can be tuned and the refrigerant capacity enhanced in terms of energy efficiency.

  19. Effect of Resveratrol as Caloric Restriction Mimetic and Environmental Enrichment on Neurobehavioural Responses in Young Healthy Mice

    Directory of Open Access Journals (Sweden)

    Mustapha Shehu Muhammad

    2014-01-01

    Full Text Available Caloric restriction and environmental enrichment have been separately reported to possess health benefits such as improvement in motor and cognitive functions. Resveratrol, a natural polyphenolic compound, has been reported to be caloric restriction mimetic. This study therefore aims to investigate the potential benefit of the combination of resveratrol as CR and EE on learning and memory, motor coordination, and motor endurance in young healthy mice. Fifty mice of both sexes were randomly divided into five groups of 10 animals each: group I animals received carboxymethylcellulose (CMC orally per kg/day (control, group II animals were maintained on every other day feeding, group III animals received resveratrol 50 mg/kg, suspended in 10 g/L of (CMC orally per kg/day, group IV animals received CMC and were kept in an enriched environment, and group V animals received resveratrol 50 mg/kg and were kept in EE. The treatment lasted for four weeks. On days 26, 27, and 28 of the study period, the animals were subjected to neurobehavioural evaluation. The results obtained showed that there was no significant change (P>0.05 in neurobehavioural responses in all the groups when compared to the control which indicates that 50 mg/kg of resveratrol administration and EE have no significant effects on neurobehavioural responses in young healthy mice over a period of four weeks.

  20. Formation of S-(carboxymethyl)-cysteine in rat liver mitochondrial proteins: effects of caloric and methionine restriction.

    Science.gov (United States)

    Naudí, Alba; Jové, Mariona; Cacabelos, Daniel; Ayala, Victoria; Cabre, Rosanna; Caro, Pilar; Gomez, José; Portero-Otín, Manuel; Barja, Gustavo; Pamplona, Reinald

    2013-02-01

    Maillard reaction contributes to the chemical modification and cross-linking of proteins. This process plays a significant role in the aging process and determination of animal longevity. Oxidative conditions promote the Maillard reaction. Mitochondria are the primary site of oxidants due to the reactive molecular species production. Mitochondrial proteome cysteine residues are targets of oxidative attack due to their specific chemistry and localization. Their chemical, non-enzymatic modification leads to dysfunctional proteins, which entail cellular senescence and organismal aging. Previous studies have consistently shown that caloric and methionine restrictions, nutritional interventions that increase longevity, decrease the rate of mitochondrial oxidant production and the physiological steady-state levels of markers of oxidative damage to macromolecules. In this scenario, we have detected S-(carboxymethyl)-cysteine (CMC) as a new irreversible chemical modification in mitochondrial proteins. CMC content in mitochondrial proteins significantly correlated with that of the lysine-derived analog N (ε)-(carboxymethyl)-lysine. The concentration of CMC is, however, one order of magnitude lower compared with CML likely due in part to the lower content of cysteine with respect to lysine of the mitochondrial proteome. CMC concentrations decreases in liver mitochondrial proteins of rats subjected to 8.5 and 25 % caloric restriction, as well as in 40 and 80 % methionine restriction. This is associated with a concomitant and significant increase in the protein content of sulfhydryl groups. Data presented here evidence that CMC, a marker of Cys-AGE formation, could be candidate as a biomarker of mitochondrial damage during aging.

  1. High-caloric and chocolate stimuli processing in healthy humans: an integration of functional imaging and electrophysiological findings.

    Science.gov (United States)

    Asmaro, Deyar; Liotti, Mario

    2014-01-10

    There has been a great deal of interest in understanding how the human brain processes appetitive food cues, and knowing how such cues elicit craving responses is particularly relevant when current eating behavior trends within Westernized societies are considered. One substance that holds a special place with regard to food preference is chocolate, and studies that used functional magnetic resonance imaging (fMRI) and event-related potentials (ERPs) have identified neural regions and electrical signatures that are elicited by chocolate cue presentations. This review will examine fMRI and ERP findings from studies that used high-caloric food and chocolate cues as stimuli, with a focus on responses observed in samples of healthy participants, as opposed to those with eating-related pathology. The utility of using high-caloric and chocolate stimuli as a means of understanding the human reward system will also be highlighted, as these findings may be particularly important for understanding processes related to pathological overeating and addiction to illicit substances. Finally, research from our own lab that focused on chocolate stimulus processing in chocolate cravers and non-cravers will be discussed, as the approach used may help bridge fMRI and ERP findings so that a more complete understanding of appetitive stimulus processing in the temporal and spatial domains may be established.

  2. Caloric Vestibular Stimulation Reduces Pain and Somatoparaphrenia in a Severe Chronic Central Post-Stroke Pain Patient: A Case Study.

    Directory of Open Access Journals (Sweden)

    Grazia Fernanda Spitoni

    Full Text Available Central post-stroke pain is a neuropathic syndrome characterized by intolerable contralesional pain and, in rare cases, somatic delusions. To date, there is limited evidence for the effective treatments of this disease. Here we used caloric vestibular stimulation to reduce pain and somatoparaphrenia in a 57-year-old woman suffering from central post-stroke pain. Resting-state functional magnetic resonance imaging was used to assess the neurological effects of this treatment. Following vestibular stimulation we observed impressive improvements in motor skills, pain, and somatic delusions. In the functional connectivity study before the vestibular stimulation, we observed differences in the patient's left thalamus functional connectivity, with respect to the thalamus connectivity of a control group (N = 20, in the bilateral cingulate cortex and left insula. After the caloric stimulation, the left thalamus functional connectivity with these regions, which are known to be involved in the cortical response to pain, disappeared as in the control group. The beneficial use of vestibular stimulation in the reduction of pain and somatic delusion in a CPSP patient is now documented by behavioral and imaging data. This evidence can be applied to theoretical models of pain and body delusions.

  3. Angelite: Paziteli na vhoda

    Directory of Open Access Journals (Sweden)

    Gerov Georgi

    2009-01-01

    Full Text Available (bugarski Statijata prosledjava ikonografskata evoljucija na izobraženijata na arhangelite Mihail i Gavriil, pomesteni pri vhoda na pravoslavnija hram. Povraten moment v neja e 13 vek. Togava arhangel Mihail započva da se izobrazjava kato voin. S tova apotropejnite mu funkcii namirat adekvaten vizualen izraz. K'm kraja na stoletieto arhangel Gavriil započva da se izobrazjava kato pisar - ikonografija, kojato šče b'de dorazvita i utv'rdena prez 14 vek. Prez postvizantijskata epoha v obraza na Mihail se pojavjavat elementi, koito akcentirat v'rhu roljata mu na psihopomp.

  4. Identification of Transient and Permanent Faults

    Institute of Scientific and Technical Information of China (English)

    李幼仪; 董新洲; 孙元章

    2003-01-01

    A new algorithm was developed for arcing fault detection based on high-frequency current transients analyzed with wavelet transforms to avoid automatic reclosing on permanent faults. The characteristics of arc currents during transient faults were investigated. The current curves of transient and permanent faults are quite similar since current variation from the fault arc is much less than the voltage variation. However, the fault current details are quite different because of the arc extinguishing and reigniting. Dyadic wavelet transforms were used to identify the current variation since wavelet transform has time-frequency localization ability. Many electric magnetic transient program (EMTP) simulations have verified the feasibility of the algorithm.

  5. X33 Transient Liftoff Analysis

    Science.gov (United States)

    Peck, Jeff; Brunty, Joseph

    2000-01-01

    The successful design of a launch vehicle requires the careful characterization of the various loads the structure will experience over its lifetime. Many of the most demanding load environments occur during the launch/ascent phase of a mission, typically defined as the point of engine start through engine cut off. One of the critical events during the launch phase is the liftoff event. This event imparts high loads on the vehicle due to transient events such as thrust build-up and vehicle release. This paper describes the theory and procedures used to calculate structural loads due to the liftoff event for the Lockheed-Martin X33 technology demonstrator vehicle. These procedures were developed at NASA's Marshall Space Flight Center and verified previously on other advanced launch system concepts and the Space Shuttle system.

  6. Transient spirals as superposed instabilities

    CERN Document Server

    Sellwood, J A

    2014-01-01

    We present evidence that recurrent spiral activity, long manifested in simulations of disk galaxies, results from the super-position of a few transient spiral modes. Each mode lasts between five and ten rotations at its corotation radius where its amplitude is greatest. The scattering of stars as each wave decays takes place over narrow ranges of angular momentum, causing abrupt changes to the impedance of the disk to subsequent traveling waves. Partial reflections of waves at these newly created features, allows new standing-wave instabilities to appear that saturate and decay in their turn, scattering particles at new locations, creating a recurring cycle. The spiral activity causes the general level of random motion to rise, gradually decreasing the ability of the disk to support further activity unless the disk contains a dissipative gas component from which stars form on near-circular orbits. We also show that this interpretation is consistent with the behavior reported in other recent simulations with l...

  7. Transient Heat Transfer in Cylinpers.

    Directory of Open Access Journals (Sweden)

    M.G. Chopra

    2000-07-01

    Full Text Available A numerical solution has been obtained for transient heat transfer in cylinders by appropriate choice of body ,conforming grid points. The physical domain is transformed to computational domain using elliptic partial differential equation technique, wherein the grid spacing becomes uniform. The advantage of this method is that the discretisation of transformed equations. and accompanying boundary conditipns becdme very simple. The applicability of this method is very broad, as it can beused for carryinI giout study of any comple'x domain in contrast to finite difference methods, which have limited applicability. Detailedcalculations have been carried out to trace the evolution of temperaturedistribution frpm the initiial stages to the steadystate for circular cylinder, elliptical cylinder and square block with circular hole. This paper is aimed for general-shaped bodies and it has been applied to studytransient heat transfer in combustion-driven shock tube.

  8. Charging transient in polyvinyl formal

    Indian Academy of Sciences (India)

    P K Khare; P L Jain; R K Pandey

    2001-08-01

    In the present paper charging and discharging transient currents in polyvinyl formal (PVF) were measured as a function of temperatures (40–80°C), poling fields (9.0 × 103–9.0 × 104 V/cm) and electrode combinations (Al–Al, Au–Al, Zn–Al, Bi–Al, Cu–Al and Ag–Al). The current–time characteristics have different values of slope lying between 0.42–0.56 and 1.42–1.63. The polarization is considered to be due to dipolar reorientation associated with structural motions and space charge relaxations due to trapping of injected charge carriers in energetically distributed traps.

  9. Avaliação da biocompatibilidade de implantes mamários de silicone esterilizados por calor seco e pelo óxido de etileno Biocompatibility assessment of silicone gel breast implants sterilized by dry-heat and by ethylene oxide

    Directory of Open Access Journals (Sweden)

    Janice Campos de Azevedo

    2006-06-01

    Full Text Available Os implantes mamários de silicone têm sido empregados, tanto nas cirurgias de aumento de mama, quanto na reconstrução do tecido mamário. A segurança biológica deste tipo de implante deve ser garantida, pois, em função da esterilização estes materiais, podem sofrer alterações oriundas dos processos esterilizantes por comprometimento da estrutura química dos polímeros. O objetivo deste trabalho consistiu na avaliação da biocompatibilidade de implantes mamários preenchidos com gel de silicone, de superfície lisa e texturizada submetidos à esterilização por calor seco e óxido de etileno. Empregou-se, para tanto, método in vitro, avaliando a citotoxicidade pelo método de captura do vermelho neutro, utilizando a linhagem celular NCTC clone 929. Os resultados obtidos demonstraram não haver comprometimento da biocompatibilidade dos biomateriais submetidos aos dois processos (calor seco e óxido de etileno, assim como comprovaram a eficácia de ambos na esterilização dos implantes.Silicone breast implants have been widely used for mammary augmentation and reconstruction surgery. Biological safety of these implants can be altered by sterilization methods. This study consisted of the biocompatibility assessment of smooth and textured silicone gel breast implants sterilized by dry-heat and ethylene oxide through cell viability, employing neutral red uptake method. The NCTC clone 929 cell were employed and the results showed no cytotoxicity of implants after both sterilization processes.

  10. Modelización matemática de la transmisión de calor en el proceso del rectificado industrial plano.

    OpenAIRE

    González-Santander Martínez, Juan Luis

    2009-01-01

    La presente tesis se encuadra en la línea de investigación de modelos matemáticos térmicos del grupo de Modelización interdisciplinar Intertech. En concreto, este trabajo presenta unos modelos matemáticos para la transmisión de calor en el rectificado industrial plano. Después de presentar los modelos de transmisión de calor del rectificado plano industrial presentes en la bibliografía: el modelo de Jaeger y el de Samara-Valencia (modelo SV), se establece una comparación entre los mismos ...

  11. Diseño de sistema de disipación de calor para aumentar la eficiencia energética de módulos fotovoltaicos

    OpenAIRE

    Serrano Canalejo, Cristina

    2016-01-01

    En este proyecto se busca la forma de enfriar módulos fotovoltaicos mediante disipadores de calor de superficie extendida. La motivación deriva de la disminución de rendimiento que experimentan los paneles al calentarse, lo cual ocurre muy a menudo debido a su exposición al Sol. Como solución se propone adherir una serie de aletas a la parte posterior del panel que disipen el calor del mismo. En el desarrollo del proyecto se busca la geometría y distribución óptimas de dichas aletas.

  12. DESHIDRATACION Y SOBREHIDRATACION VOLUNTARIAS DURANTE EL EJERCICIO EN EL CALOR: POSIBLES FACTORES RELACIONADOS

    Directory of Open Access Journals (Sweden)

    Andrea Solera Herrera

    2006-12-01

    Full Text Available Los efectos negativos de la deshidratación sobre la salud y el rendimiento han sido bien documentados. Recientemente, también se han documentado problemas por sobrehidratación. La presente investigación se hizo para estudiar los posibles factores que influyen sobre la ingesta voluntaria de líquido durante el ejercicio y determinar si existe relación entre el grado de deshidratación voluntaria y la creencia de que la ingesta de líquido provoca cólico. Para ello, se contó con 94 estudiantes universitarios jóvenes, varones, quienes se ejercitaron a un 60% de su FCmáx durante una hora, alternando cada 10 min. entre bicicleta estacionaria, subir y bajar un escalón, y una máquina simuladora de esquí. Esto se realizó en un laboratorio de ambiente controlado a 30úC, 70% humedad relativa. Durante el ejercicio se midió la ingesta voluntaria de una bebida deportiva, así como también las percepciones de calor ambiental, llenura estomacal, malestar gastrointestinal y palatabilidad de la bebida. Los sujetos fueron pesados desnudos y secos antes y después del ejercicio. Al final se les aplicó un cuestionario sobre la importancia de la hidratación, y sus creencias sobre el cólico. El equilibrio hídrico promedio fue de 0.14 ± 0.98% del peso corporal, con un rango entre -2.38% y 2.84%. La tasa de sudoración promedio fue de 1208.3 ± 381.7ml·h-1; y la ingesta de 1132 ± 610ml·h-1. Dos análisis de regresión múltiple determinaron que: (a los predictores más fuertes de la ingesta voluntaria de líquido fueron la importancia asignada a la hidratación durante el ejercicio (R2 = 0.13; p < 0.0005 y la percepción de llenura estomacal al minuto 25 (R2 = 0.08; p = 0.005; (b los predictores más fuertes del equilibrio hídrico fueron la ingesta voluntaria por kg de peso (R2 = 0.73; p < 0.0005, y la tasa de sudoración (R2 = 0.08; p = 0.006. No obstante, el equilibrio hídrico no estuvo asociado con ninguna de las percepciones, ni con las

  13. [Vibratory test and head shaking test and caloric test: a series of 87 patients].

    Science.gov (United States)

    Dumas, G; Lavieille, J P; Schmerber, S

    2004-02-01

    The purpose of this work was to study the complementary contribution of the vibratory test (VT), the head shaking test (HST) and the caloric test (CT) in patients with total or partial vestibular lesions. We investigated the usefulness of these three tests, particularly the high frequency VT, for multiple-frequency vestibular study. The study cohort included 40 patients with total vestibular lesions (TVL) and 47 patients with partial vestibular lesions (PVL), the latter group including 21 patients with recent Menière disease, 15 with sudden-onset loss of vestibular function (SLVF), 5 with tumors of the cerebropontine angle, and six with diverse conditions. The HST protocol was 2 Hz stimulation (head speed greater than 180 degrees /s). The VT used an ABC 100 Hz vibrator operating at 0.8 mm and an S stimulator delivering frequencies between 30 and 115 Hz during 10 s stimulations. An LIVN-2 videoscope (biodigital France) and a 2D and 3D videonystagmograph (synapsis France) were used for the recordings. Mastoid stimulation was used for the VT. For the 40 patients with TVL, the three tests (VT, CT, HST) were in agreement for all frequencies. The nystagmus produced by the VT demonstrated a horizontal component in 96% of the patients, a vertical component in 47%, and a rotational component in 30%. For the 47 patients with PVL, 9 of the 21 with Menière disease had a normal CT. Conversely, nystagmus was triggered by the HST in 10 and by the VT in 6. Nystagmus triggered by the VT and the HST was non-coherent with opposing direction in two-thirds of the patients. In certain cases, the VT demonstrated a variation in the direction of the nystagmus depending on the stimulation frequency, 30 or 100 Hz. Among the 15 patients with SLVF, the HST triggered nystagmus in only 5 and the VT in 14 (5 patients had nystagmus non-coherent with the side of the lesion). For the 5 patients with tumors of the cerebropontine angle (small neuroma or meningioma), the CT was negative in all 5, the

  14. Transferencia de calor y su efecto en el proceso de prensado de tableros contrachapados

    Directory of Open Access Journals (Sweden)

    D. Zavala Zavala

    2004-01-01

    Full Text Available El proceso de prensado determina la calidad de los contrachapados (triplay a través de la interrelación de las propiedades tecnológicas de la madera, de las características de los adhesivos y de la interacción de la temperatura y presión que se generan en la prensa. Este trabajo se realizó con la finalidad de analizar el efecto de la transferencia de calor en la polimerización de adhesivos preparados con urea y fenol formaldehído, para determinar la secuela optima de prensado de triplay de 6, 9, 12, 15, 18 y 34 mm de espesor; y para evaluar la compactación de los tableros por efecto de la temperatura y presión durante el prensado. Se utilizó chapa de Pinus herrerai Martínez, P. michoacana Martínez y P. pseudostrobus Lindl., a un contenido de humedad de 6 a 8 %, una prensa calentada con vapor, adhesivo de urea formaldehído para tableros para interiores de 6, 9, 12, 15 y 18 mm y fenol formaldehído para triplay para exteriores de 34 mm de espesor. Se utilizaron ciclos de prensado aplicando temperaturas de 115, 130 y 140 °C y presiones de 10.62 kg·cm-2 (151 psi y 8.51 kg·cm-2 (121 psi en triplay para interiores, y para los tableros tipo exterior de 140, 150 y 160 °C de temperatura y 12.23, 13.29 y 14.34 kg·cm-2 (174, 189 y 204 psi de presión. La temperatura de las líneas de pegamento más externas aumenta rápidamente al cerrarse la prensa y manifiesta una diferencia en relación a las más internas, que tiende a reducirse conforme transcurre el tiempo de prensado, igualándose aproximadamente al 73 % del tiempo para cada tipo de tablero. A través de la evaluación de adhesión de los pegamentos de los tableros para interiores con la norma PS1-95, se determinó que todos pasan las especificaciones requeridas para ese uso En los tableros de 34 mm de espesor, con un incremento de la temperatura de 140 a 160 °C, una presión de 12.23 a 14.34 kg·cm-2 (174 a 204 psi y un contenido de sólidos del fenol formaldehído de 29.9 a 32

  15. PREFACE: XVth International Conference on Calorimetry in High Energy Physics (CALOR2012)

    Science.gov (United States)

    Akchurin, Nural

    2012-12-01

    The XVth International Conference on Calorimetry in High Energy Physics, CALOR2012, was held in Santa Fe, New Mexico from 4-8 June 2012. The series of conferences on calorimetry started in 1990 at Fermilab, and they have been the premier event for calorimeter aficionados, a trend that CALOR2012 upheld. This year, several presentations focused on the status of the major calorimeter systems, especially at the LHC. Discussions on new and developing techniques in calorimetry took a full day. Excellent updates on uses of calorimeters or about ideas that are deeply rooted in particle physics calorimetry in astrophysics and neutrino physics were followed by talks on algorithms and special triggers that rely on calorimeters. Finally, discussions of promising current developments and ongoing R&D work for future calorimeters capped the conference. The field of calorimetry is alive and well, as evidenced by the more than 100 attendees and the excellent quality of over 80 presentations. You will find the written contributions in this volume. The presentations can be found at calor2012.ttu.edu. The first day of the conference was dedicated to the LHC. In two invited talks, Guillaume Unal (CERN) and Tommaso Tabarelli de Fatis (Universita' & INFN Milano Bicocca) discussed the critical role electromagnetic calorimeters play in the hunt for the Standard Model Higgs boson in ATLAS and CMS, respectively. The enhanced sensitivity for light Higgs in the two-gamma decay channel renders electromagnetic calorimeters indispensible. Much of the higher mass region was already excluded for the SM Higgs by the time of this conference, and after less than a month, on 4 July, CERN announced the discovery of a new boson at 125 GeV, a particle that seems consistent with the Higgs particle so far. Once again, without the electromagnetic calorimeters, this would not have been possible. Professor Geoffrey West from the Santa Fe Institute gave the keynote address. His talk, 'Universal Scaling Laws

  16. Stem heat balance method to estimate transpiration of young orange and mango plants Balanço de calor caulinar para estimativa da transpiração de plantas jovens de laranja e manga

    Directory of Open Access Journals (Sweden)

    Lucas M. Vellame

    2010-01-01

    Full Text Available The present study had as its main objective the evaluation of the heat balance method in young orange and mango plants under protected environment. The work was carried out at Embrapa Cassava and Tropical Fruits, Cruz das Almas, BA. Later on, estimates of sap flow were conducted for two mango plants cultivated in pots of 15 and 50 L installed on weighting platforms of 45 and 140 kg; sap flow was determined in three orange plants, two of which were also installed on weighing platforms. The values of sap flow were compared to the transpiration measured by lysimeters at integrated intervals of 1, 2, 4 and 24 h. The heat balance method showed good precision for estimating daily transpiration (R² = 0.95 and R² = 0.90, accompaning the availability of energy in the system, underestimating on average 4.6% of the daily transpiration in orange plants and overestimating in about 0.3% the daily transpiration of mango plants under conditions of good water supply. The heat balance method underestimated by 16% the transpiration in orange under conditions of water deficit.Com o presente estudo se objetivou avaliar o método de balanço de calor em plantas jovens de laranja e manga em ambiente protegido. O trabalho foi conduzido na Embrapa Mandioca e Fruticultura, Cruz das Almas, BA. Realizaram-se estimativas de fluxo de seiva em duas plantas de manga plantadas em vasos de 15 e 50 L, instalados sobre plataformas de pesagem de 45 e 140 kg; posteriormente, o fluxo de seiva foi determinado em três plantas de laranja, duas também instaladas em lisímetros de pesagem. Os valores de fluxo de seiva obtidos foram comparados com a transpiração medida pelos lisímetros em intervalos de integração de 1, 2, 4 e 24 h. O método do balanço de calor mostrou-se preciso na estimativa da transpiração diária (R² = 0,95 e R² = 0,90, que acompanhou a disponibilidade de energia do sistema, subestimando em média, 4,6% a transpiração diária em plantas de laranja e

  17. Transient receptor potential channels in essential hypertension

    DEFF Research Database (Denmark)

    Liu, Daoyan; Scholze, Alexandra; Zhu, Zhiming

    2006-01-01

    The role of nonselective cation channels of the transient receptor potential channel (TRPC) family in essential hypertension has not yet been investigated.......The role of nonselective cation channels of the transient receptor potential channel (TRPC) family in essential hypertension has not yet been investigated....

  18. The LOFAR Transients Key Science Project

    NARCIS (Netherlands)

    Stappers, B.; Fender, R.; Wijers, R.

    2009-01-01

    The Transients Key Science Project (TKP) is one of six Key Science Projects of the next generation radio telescope LOFAR. Its aim is the study of transient and variable low-frequency radio sources with an extremely broad science case ranging from relativistic jet sources to pulsars, exoplanets,

  19. Asiago spectroscopic classification of two transients

    Science.gov (United States)

    Turatto, M.; Benetti, S.; Tomasella, L.; Cappellaro, E.; Elias-Rosa, N.; Ochner, P.; Pastorello, A.; Terreran, G.

    2016-12-01

    The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic observation of Gaia16bzi, AT2016isl. The targets were supplied by the ESA Gaia Photometric Science Alerts Team and DPAC (http://gsaweb.ast.cam.ac.uk/alerts), the Tsinghua-NAOC Transient Survey (TNTS) and by Kunihiro Shima..

  20. Transient age distributions in subsurface hydrologic systems

    Science.gov (United States)

    Engdahl, Nicholas B.; McCallum, James L.; Massoudieh, Arash

    2016-12-01

    Transient age distributions have received relatively little attention in the literature over the years compared to their steady-state counterparts. All natural systems are transient given enough time and it is becoming increasingly clear that understanding these effects and how they deviate from steady conditions will be important in the future. This article provides a high-level overview of the equations, techniques, and challenges encountered when considering transient age distributions. The age distribution represents the amount of water in a sample belonging to a particular age and the transient case implies that sampling the same location at two different times will result in different age distributions. These changes may be caused by transience in the boundary conditions, forcings (inputs), or physical changes in the geometry of the flow system. The governing equation for these problems contains separate dimensions for age and time and its solutions are more involved than the solute transport or steady-state age equations. Despite the complexity, many solutions have been derived for simplified, but transient, approximations and several numerical techniques exist for modeling more complex transient age distributions. This paper presents an overview of the existing solutions and contributes new examples of transient characteristic solutions and transient particle tracking simulations. The limitations for applying the techniques described herein are no longer theoretical or technological, but are now dominated by uncertainty in the physical properties of the flow systems and the lack of data for the historic inputs.