Auswahl der wissenschaftlichen Literatur zum Thema „Nocturnal bees“

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Zeitschriftenartikel zum Thema "Nocturnal bees"

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Warrant, Eric J. „Nocturnal bees“. Current Biology 17, Nr. 23 (Dezember 2007): R991—R992. http://dx.doi.org/10.1016/j.cub.2007.09.009.

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Cordeiro, Guaraci D., Rodolfo Liporoni, Carolina A. Caetano, Cristiane Krug, Carlos A. Martínez-Martínez, Herbeson O. J. Martins, Renan K. O. A. Cardoso et al. „Nocturnal Bees as Crop Pollinators“. Agronomy 11, Nr. 5 (20.05.2021): 1014. http://dx.doi.org/10.3390/agronomy11051014.

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Bees are typically diurnal but around 1% of described species have nocturnal activity. Nocturnal bees are still poorly studied due to bias towards studying diurnal insects. However, knowledge concerning their biology and role as crop pollinators has increased. We review the literature on nocturnal bees’ traits and their host plants, and assess the crop pollination effectiveness of this neglected group. Nocturnal bees have visual adaptations to cope with low light intensities, and floral scents are a key sensory cue used to find their host flowers. Nocturnal bees generally show high flower constancy, the ability to vibrate flowers, and high transfer rates of pollen grains to stigmas. The flowers visited by nocturnal bees range from small radial and zygomorphic flowers to large brush blossoms; moreover, they visit plants with different flowering strategies. Nocturnal bees are effective pollinators of regional fruit crops in Brazil, such as cambuci (Campomanesia phaea), guaraná (Paullinia cupana), cajá (Spondias mombin), and in North America of cultivated pumpkins (Cucurbita species). However, they most likely are pollinators of several other crops. Strategies to host high numbers of nocturnal bees around cropping areas should be taken, such as preserving adjacent native forests, restricting soil management, providing food resources beyond crop flowers, and avoiding light pollution.
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Land, Michael F. „Nocturnal Vision: Bees in the Dark“. Current Biology 14, Nr. 15 (August 2004): R615—R616. http://dx.doi.org/10.1016/j.cub.2004.07.043.

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Somanathan, Hema, Renee Maria Borges, Eric James Warrant und Almut Kelber. „Nocturnal bees learn landmark colours in starlight“. Current Biology 18, Nr. 21 (November 2008): R996—R997. http://dx.doi.org/10.1016/j.cub.2008.08.023.

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Carvalho, Airton Torres, Artur Campos Dalia Maia, Poliana Yumi Ojima, Adauto A. dos Santos und Clemens Schlindwein. „Nocturnal Bees are Attracted by Widespread Floral Scents“. Journal of Chemical Ecology 38, Nr. 3 (März 2012): 315–18. http://dx.doi.org/10.1007/s10886-012-0084-z.

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Warrant, Eric J., Almut Kelber, Rita Wallén und William T. Wcislo. „Ocellar optics in nocturnal and diurnal bees and wasps“. Arthropod Structure & Development 35, Nr. 4 (Dezember 2006): 293–305. http://dx.doi.org/10.1016/j.asd.2006.08.012.

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Kelber, Almut, Eric J. Warrant, Michael Pfaff, Rita Wallén, Jamie C. Theobald, William T. Wcislo und Robert A. Raguso. „Light intensity limits foraging activity in nocturnal and crepuscular bees“. Behavioral Ecology 17, Nr. 1 (16.11.2005): 63–72. http://dx.doi.org/10.1093/beheco/arj001.

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Siqueira, Estefane, Reisla Oliveira, Stefan Dötterl, Guaraci Duran Cordeiro, Isabel Alves-dos-Santos, Theo Mota und Clemens Schlindwein. „Pollination of Machaerium opacum (Fabaceae) by nocturnal and diurnal bees“. Arthropod-Plant Interactions 12, Nr. 5 (29.06.2018): 633–45. http://dx.doi.org/10.1007/s11829-018-9623-z.

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Miyake, Takashi, und Tetsukazu Yahara. „Why does the flower of Lonicera japonica open at dusk?“ Canadian Journal of Botany 76, Nr. 10 (01.10.1998): 1806–11. http://dx.doi.org/10.1139/b98-119.

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We investigated contributions of diurnal pollinators and a nocturnal pollinator to pollen transfer in Lonicera japonica (Caprifoliaceae), whose flowers have traits typical of the hawkmoth-pollination syndrome. Diurnal bees, Tetralonia nipponensis and Lasioglossum sp., delivered more pollen grains than the nocturnal hawkmoth Theretra japonica per visit, suggesting that these bees were also effective pollinators. However, these bees removed over 10 times more pollen at one visit than the hawkmoth. Because of the higher pollen consumption by these bees, anthesis at dusk is considered to be optimal for Lonicera japonica to maximize overall pollen transfer under the visitation of both nocturnal and diurnal pollinators. Tetralonia japonica dispersed color dye farther than the other pollinators, which suggests that the nocturnal pollinator contributes more to cross-pollination than the diurnal pollinators.Key words: Lonicera japonica, hawkmoth-pollinated flowers, pollinator efficiency, pollen removal, pollination syndromes, timing of anthesis.
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Gorostiague, Pablo, und Pablo Ortega-Baes. „Pollination biology of Echinopsis leucantha (Cactaceae): passerine birds and exotic bees as effective pollinators“. Botany 95, Nr. 1 (Januar 2017): 53–59. http://dx.doi.org/10.1139/cjb-2016-0120.

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Cactus flowers have traditionally been considered to be specialized to certain pollination guilds, but pollination studies reveal that most species are actually generalists. This suggests that floral traits are not always predictive of the animal visitors that pollinate cactus flowers. Here, we studied the pollination of Echinopsis leucantha (Gillies ex Salm-Dyck) Walp., an endemic cactus of Argentina, whose floral traits would suggest that it is pollinated by moths. The floral lifespan and flower availability throughout the reproductive period were evaluated. Field experiments were carried out to study the reproductive system and the identity and effectiveness of floral visitors. Echinopsis leucantha flowers had a nocturnal anthesis time that extended into the following morning. The species was self-incompatible. Floral visitors included moths, bees, and passerine birds. However, diurnal visitors were more effective as pollinators than nocturnal ones. The flowers of E. leucantha were phenotypically specialized (sphingophily); however, the pollination system was functionally and ecologically generalized. The results confirm that generalized pollination systems are widespread among species of the Echinopsis genus with nocturnal flowers, for which diurnal pollinators seem to have a key role in fruit and seed production. Our study constitutes the first record of passerine bird pollination in the Cactaceae for mainland South America.
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Dissertationen zum Thema "Nocturnal bees"

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Dias, Rodolfo Liporoni. „Visual ecology of nocturnal bees: how light intensity affects foraging activity in cambuci, a neotropical Myrtaceae“. Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-21082018-082154/.

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The foraging activity of day-active bees often rely on flower availability, light intensity and temperature. However, some bees developed a nocturnal habit and fly during the dusk, dawn and night. We still do not know how these bees cope with environmental factors, especially dimmer light levels, to explore flower earlier than their diurnal relatives. Given that typical bee apposition compound eyes work better in brighter environments and function in their limits in dim-light conditions, we can expect a larger dependence of light intensity for nocturnal groups. Nocturnal and crepuscular bees are frequent visitors of cambuci (Campomanesia phaea, Myrtaceae) in southeastern Brazil. We aimed to investigate how light intensity affects flower visitation of cambuci by nocturnal and crepuscular bees, also controlling for other environmental factors. We counted visits per minute along 30 nights/twilights in 33 cambuci trees from a commercial orchard, measuring the following environmental variables: light intensity, flower availability, temperature, air relative humidity and wind speed. Light intensity is the only variable that explained flower visitation of nocturnal bees in cambuci, which peaks at intermediate light levels that occur around 30 minutes before sunrise. The minimum light intensity threshold to bees start flying is of 0.00024 cd/m2, the first recorded value for nocturnal and crepuscular bees finding flowers in an agro-forest context. Our results highlight for the first time how nocturnal bees rely on light to explore resources and show that the bees light-dependent foraging activity is not always linear, as postulated by previous theoretic models. This is the first step to understand how nocturnal bees react to environmental factors. Our findings also bring concerns about possible negative effects of light pollution at night for cambuci-crepuscular bees interaction
O forrageio de abelhas geralmente depende de disponibilidade de flores, intensidade de luz e temperatura. Contudo, algumas abelhas desenvolveram hábitos noturnos e voam durante os crepúsculos e a noite. Não se sabe como essas abelhas lidam com os fatores ambientais, especialmente os reduzidos níveis de luminosidade. Dado que os olhos compostos de aposição de abelhas funcionam melhor em maiores luminosidades, espera-se uma maior dependência da luz para os grupos noturnos. Abelhas noturnas e crepusculares são visitantes frequentes do cambuci (Campomanesia phaea, Myrtaceae) no sudeste do Brasil. Nosso objetivo foi investigar como a intensidade de luz afeta a visitação floral do cambuci por abelhas noturnas e crepusculares, controlada também por outros fatores ambientais. Para isso, contamos as visitas a cada minuto ao longo de 30 noites/crepúsculos em 33 árvores de cambuci em um pomar comercial, medindo as seguintes variáveis ambientais: intensidade de luz, disponibilidade de flores, temperatura, umidade e velocidade do vento. A intensidade de luz foi a única variável que explicou a visitação floral de abelhas noturnas no cambuci, a qual tem um pico em níveis intermediários de luz que ocorrem ao redor de 30 minutos antes do nascer do sol. O limiar mínimo de intensidade de luz para as abelhas começarem a voar foi de 0.00024 cd/m2, o primeiro valor registrado para abelhas noturnas e crepusculares procurando por flores em um contexto agroflorestal. Nossos resultados destacam pela primeira vez como as abelhas noturnas dependem da luz para explorar recursos e mostram que essa dependência, para abelhas em geral, não é sempre linear, como postulado por modelos teóricos prévios. Este é o primeiro passo para entender como abelhas noturnas reagem a fatores ambientais. Nossos dados também trazem alertas para possíveis efeitos negativos da poluição luminosa à noite para a interação entre cambuci e abelhas noturnas
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Caetano, Carolina de Almeida. „Abelhas crepusculares/ noturnas: adaptações morfológicas e interações com plantas“. Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-18102016-111327/.

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As abelhas utilizam sinais visuais e olfatórios para encontrar plantas das quais utilizam recursos florais. Algumas abelhas adquiriram hábitos crepuscular ou noturno e forrageiam durante períodos de pouca luminosidade. Algumas espécies de abelhas noturnas são conhecidas por possuírem adaptações morfológicas do sistema visual que lhes permitem o voo noturno, e assim facilitam o encontro de plantas que podem ser utilizadas como recursos. No presente estudo investigamos se espécies crepusculares Megalopta sodalis, Megommation insigne e Ptiloglossa latecalcarata, que utilizam Campomanesia phaea como recurso, e possuem adaptações na morfologia externa do sistema visual. A hipótese principal é que seriam encontrados olhos compostos, omatídeos e ocelos maiores, assim como menor quantidade de omatídeos nos olhos compostos quando comparadas às abelhas diurnas. Para tanto, medimos o comprimento, área e número de omatídeos dos olhos compostos, assim como o diâmetro dos omatídeos e ocelos. A distância intertegular foi medida para ter um controle do tamanho corporal. Além das abelhas crepusculares acima citadas, utilizamos as abelhas diurnas Bombus brasiliensis, Bombus morio, Melipona bicolor e Euglossa cordata para comparação. Para a medida dos olhos fizemos um molde de esmalte e a partir deste obtivemos imagens que foram analisadas utilizando-se o software ImageJ e Matlab. Para as outras medidas, foram obtidas imagens em estereomicroscopio que foram analizadas com o ImageJ. Utilizamos a análise estatística de permutação para ver se havia diferença entre as abelhas crepusculares e diurnas, e correlação de Spearman para ver se a medida estava correlacionada à distância intertegular. Foi realizado um levantamento das espécies com registro de interação com abelhas crepusculares e noturnas e de suas características florais com uma respectiva análise descritiva. As abelhas crepusculares deste estudo possuem o diâmetro dos ocelos e omatídeos maiores e olhos compostos com maior comprimento e área, e menor número de omatídeos. Algumas variáveis estão correlacionadas com a distância intertegular. As flores visitadas por abelhas noturnas possuem em sua maioria cores claras, perfume acentuado e são odoríferas. As abelhas crepusculares deste estudo possuem adaptações na morfologia externa, o que lhes permite o voo no período de pouca luminosidade. Algumas espécies de abelhas que forrageiam em período de pouca luminosidade visitaram flores de cores fortes e uma não odorífera, isso pode estar relacionado à capacidade de reconhecer cores em ambientes pouco iluminados. Algumas espécies de abelhas forrageiam durante o dia e a noite, essa plasticidade do comportamento pode ser um caminho pelo qual caracteres vantajosos para esse ambiente sejam selecionados. Para as plantas, ter as abelhas noturnas como polinizadoras pode ser vantojoso. Então plantas que possuem sinais reconhecidos pelas abelhas noturnas podem se beneficiar com a polinização noturna, evitando o disperdício de pólen com as abelhas diurnas. A maioria das abelhas foi generalista na utlilização do recurso, mas parece haver preferência por certas espécies de plantas
The bees use visual cues and olfactory to find plants which own floral resources. Some bees acquired crepuscular or nocturnal habits and foraging during periods of low light. Some nocturnal bees species are recognized to possess morphological adaptations of the visual system that enable them to practice the night flight, and thus facilitate the matching of plants that can be used as resources. In the present study we investigated whether crepuscular species Megalopta sodalis, Megommation insigne e Ptiloglossa latecalcarata, using Campomanesia phaea as a resource, have adaptations in the external morphology of the visual system. The main hypothesis was that the eyes were composed of ommatidia and larger ocelli as well as lower amount of ommatidia in the compound eyes when compared to daytime bees. Therefore, we measure the length, the area and number of ommatidia of the compound eye and also the diameter of the ommatidia, ocelli, and intertegular distance to have a control of body size. In addition to the crepuscular bees mentioned above, we used the diurnal bees Bombus brasiliensis, Bombus morio, Euglossa cordata, and Melipona bicolor for comparison. For the measurement of eyes, we made a nail polish mold and from this mold was obtained images which were analyzed using ImageJ and Matlab software. For other measures, we obtained images in stereomicroscope that were analyzed only using ImageJ. We use the statistical analysis of permutation to observe if there was any difference between the crepuscular and diurnal bees, and Spearman correlation to see if the measure was correlated with distance intertegular. In addition, we conducted a survey of species interaction with record crepuscular and nocturnal bees and their floral characteristics with a descriptive analisys. The crepuscular bees in this research have lager diameter of omatidea and ocelli, and larger area and length of compound eyes, and less number of omatidea per eye. Most of the flowers visited by nocturnal bees have pale color, scent and nocturnal anthesis. Some bee species that forage in low light visit flowers with strong color, and one bee visited flower without scent, this can be related with capacibility to recoginized colors in environments with low light. Some bees forage during day and night, this phenotypic plasticity of behavior can be a way that advantageous characters for this environment are selected. For plants can be advantageous. Then plants that posses sinals recognized by nocturnal and crepuscular bees can be benefited through nocturnal pollination, avoiding daylight bees waste their polen. The most of bees were generalists in their utilization of flower resource but seems to have preference for some plant species
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Cordeiro, Guaraci Duran. „Fenologia reprodutiva, polinização e voláteis florais do cambuci (Campomanesia phaea - Myrtaceae)“. Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/59/59131/tde-20042015-222512/.

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A família Myrtaceae tem muitas espécies frutíferas, algumas são utilizadas comercialmente, entre elas o cambuci (Campomanesia phaea). Os objetivos deste trabalho foram descrever a fenologia reprodutiva, a biologia floral, o sistema reprodutivo e identificar os polinizadores do cambuci para gerar novos conhecimentos que possam contribuir com a produtividade desta espécie. O estudo de fenologia reprodutiva foi conduzido por dois anos, em área de ocorrência natural e área de cultivo comercial. As fenofases (floração e frutificação) foram monitoradas com duas métricas: Índice de atividade (sincronia) e Índice de intensidade (intensidade - Fournier) e correlacionadas com fatores abióticos (temperatura, pluviosidade e comprimento do dia). Os resultados mostraram que a floração e frutificação na área de ocorrência natural e cultivo foram diferentes, mesmo sob mesmas condições climáticas. A floração e frutificação foram mais intensas e sincrônicas na área de cultivo. Os fatores abióticos não explicaram estas diferenças nas fenofases entre as áreas de estudo, porém a adubação do solo e diversidade de polinizadores tiveram papel importante. No estudo de polinização de C. phaea foram observados a duração de antese, recursos florais, receptividade do estigma e viabilidade polínica. O sistema reprodutivo de C. phaea foi investigado baseado na razão P:O e pelos experimentos de polinização manual. Os visitantes florais foram capturados e os polinizadores mais eficientes foram determinados, conforme número de pólen depositado no estigma e número de frutos produzidos. As flores de C. phaea duram dois dias, são hermafroditas e têm o pólen como o único recurso disponível para os visitantes florais. A antese é noturna e começa em torno das 5 h. O sistema reprodutivo de C. phaea é o autoincompatível. Foram coletadas 52 espécies de visitantes florais e entre elas as mais eficientes na polinização foram as abelhas noturnas e crepusculares (Megalopta sodalis, Megommation insigne, Ptiloglossa latecalcarata e Zikanapis seabrai). Além destas abelhas, as flores de C. phaea também foram visitadas e polinizadas por Apis mellifera nos períodos crepusculares e diurnos. Para entender como as abelhas noturnas/crepusculares encontram as flores do cambuci no escuro foram coletadas amostras dos voláteis florais (a noite e durante o dia), pelo método de dynamic headspace e posteriormente analisados por GC-MS. Experimentos eletroantenográficos (GC-EAD) e biotestes foram realizados para testar se os compostos identificados das flores do cambuci são capazes de estimular respostas eletrofisiológicas e comportamentais nas abelhas noturnas/crepusculares. Foram encontrados 14 compostos voláteis nas flores de C. phaea, os mesmos nas amostras da noite e do dia, embora a composição relativa do odor tenha diferido entre os dois períodos. A emissão dos voláteis é maior a noite durante a atividade das abelhas noturnas/crepusculares, e alguns compostos são mais eminentes durante a noite (ex, 1-Octanol) e outros ao dia (ex, 2-Phenylethanol). As abelhas noturnas foram atraídas para os odores sintéticos da flor do cambuci. Apis mellifera também respondeu positivamente ao teste eletroantenográfico e biotestes. Os resultados mostraram que os voláteis emitidos a noite pelas flores de C. phaea tem função atrativa para as abelhas noturnas/crepusculares, e sugere que 1-Octanol possa ser o composto chave nesta atração.
The family Myrtaceae has many fruiting species, some are commercially explored. Among those species is the cambuci (Campomanesia phaea). The objectives this work were to describe the reproductive phenology, the floral biology, the reproductive system, and to identify the pollinators of cambuci in order to generate new knowledge that may help increase the productivity of this species. The study about reproductive phenology was conducted for two years, in an area of natural occurrence and in a commercial crop. The phenophases (flowering and fruit set) were monitored with Activity index (synchrony) and Intensity index (Fournier intensity) and correlated with abiotic factors (temperature, rainfall, and day length). The results showed that flowering and fruit set of C. phaea in natural area and crop were different even under same climatic conditions. The flowering and fruit set were more intense and synchrony in the crop. The abioctic factors do not explain these differences in the phenophases between the study areas, but other variables, such as soil fertilization and pollinator diversity, play an important role. In the pollination study of C. phaea were observed the anthesis duration, floral resources, stigma receptivity, and pollen viability. The reproductive system of C. phaea was investigated based on the P:O ratio and by carrying out manual pollination tests. The flower visitors were captured and determined the most efficient pollinators, according to effectiveness by number of pollen grains deposited in the stigma and number of fruit set. The flowers of C. phaea last two days, are hermaphrodite, and have pollen as the only resource offered to flower visitors. Its anthesis is nocturnal and begins around 5 h. The reproductive system of C. phaea is self-incompatible. Were collected 52 species of flower visitors and among them the most efficient in pollination were nocturnal and crepuscular bees (Megalopta sodalis, Megommation insigne, Ptiloglossa latecalcarata e Zikanapis seabrai). Besides these bees, the flowers of C. phaea flowers were also visited and pollinated by Apis mellifera in crepuscular and diurnal periods. In order to understand how the nocturnal/crepuscular bees find cambuci flowers in darkness flower volatiles were collected (at night and during the day) by dynamic headspace method and after analyzed by GC-MS. In addition, electroantennographic (GC-EAD) and behavioural experiments (bioassays) were performed to test if compounds identified from cambuci flowers are capable in eliciting electrophysiological and behavioural responses in nocturnal/crepuscular bees. In total 14 volatiles compounds were found in C. phaea flowers, the same in the night and day samples. Although, the relative scent composition differed between these two periods. The volatile emission is higher during the activity of nocturnal/crepuscular bees, and some compounds are more eminent during the night (e.g., 1-Octanol) and some during the day (e.g., 2-Phenylethanol). The nocturnal/crepuscular were attracted by synthetic scent of the cambuci flowers. Apis mellifera also showed positive responds towards for electroantennographic and behavioural bioassays. The results showed that volatiles emitted at night by C. phaea flowers have attractive function to nocturnal/crepuscular bees, and suggest that 1-Octanol can be the key compound for this attraction.
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Bücher zum Thema "Nocturnal bees"

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Horowitz, Sandra L. “I Am Pregnant; Why Can’t I Sleep?”. Herausgegeben von Angela O’Neal. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190609917.003.0029.

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This chapter reviews the common sleep disorders of pregnancy. During pregnancy and postpartum, 84% of women report poor sleep at least a few nights a week. These problems are common, disruptive to daytime and nighttime activity, and may have multiple causes. This chapter covers aspects of insomnia and restless leg syndrome. It also discusses sleep apnea in pregnancy with related hormonal changes that may increase the incidence. There is an association of sleep apnea and pregnancy-induced hypertension, with increased adverse outcomes of pregnancy, including fetal growth retardation and premature birth. It has been suggested that treating nocturnal airflow limitation may improve gestational hypertension. The recommended therapies in this chapter may also be applied to non-pregnant patients with similar complaints.
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Sokolov, Elisaveta, und K. Ray Chaudhuri. An overview of sleep dysfunction in Parkinson disease. Herausgegeben von Sudhansu Chokroverty, Luigi Ferini-Strambi und Christopher Kennard. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199682003.003.0025.

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Disturbances in nocturnal sleep and their consequences during waking in Parkinson disease (PD) were recognized in 1817 by James Parkinson, who described sleep problems in his case series as follows: “His attendants observed, that of late the trembling would sometimes begin in his sleep, and increase until it awakened him: when he always was in a state of agitation and alarm.” Sleep disturbance in PD is complex, with a prevalence of up to 98%, and has been shown to be a key determinant of quality of life. Sleep disturbances in PD are heterogeneous, ranging from insomnia to drug-induced sleep disorders, and now can be assessed by simple validated bedside tools such as the Parkinson’s Disease Sleep Scale (PDSS). Also, sleep, contrary to previous perceptions, can be disordered not just in advanced PD, but also in the pre-motor as well as the untreated states.
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Ross, Joanna, Andrew J. Hearn und David W. Macdonald. The Bornean carnivore community: lessons from a little-known guild. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198759805.003.0014.

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Niche differentiation reduces competition between species and modifies predation risk such that species coexistence is promoted. Temporal partitioning is a type of niche differentiation that has only relatively recently been specifically investigated. In this chapter, data from 515 camera trap stations from Sabah, Malaysian Borneo is used to describe the presence, habitat associations and activity patterns of Bornean carnivores and to investigate temporal partitioning between species. Primary and old logged forest were the most species rich sites and small forest fragments and oil palm plantations supported the fewest species. Species’ activity patterns within families were more similar than those between families. Only the masked palm civet and sun bear showed variation in activity among habitats. Considering the species as rough trophic groups rather than families revealed that each group contained both diurnal and nocturnal species, which presumably helps to promote coexistence between the musteloids and other species in each group.
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Le Fanu, J. Sheridan. In a Glass Darkly. Herausgegeben von Robert Tracy. Oxford University Press, 2008. http://dx.doi.org/10.1093/owc/9780199537983.001.0001.

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‘The ideal reading…for the hours after midnight.’ Thus Henry James described the style of supernatural tale of which Sheridan Le Fanu was a master. Known in nineteenth-century Dublin as ‘The Invisible Prince’ because of his reclusive and nocturnal habits, Le Fanu was fascinated by the occult. His writings draw on the Gothic tradition, elements of Irish folklore, and even on the social and political anxieties of his Anglo-Irish contemporaries. In exploring sometimes inexplicable terrors, the tales focus on the unease of the haunted men and women who encounter the supernatural, rather than on the origin or purpose of the visitant. This makes for spine-chilling reading. The five stories presented here have been collected by Dr Hesselius, a ‘metaphysical’ doctor, the forerunner of the modern psychiatrist, who is willing to consider the ghosts both as real and as hallucinatory obsessions. The reader’s doubtful anxiety mimics that of the protagonist, and each story thus creates that atmosphere of mystery which is the supernatural experience.
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Kaplan, Gisela. Tawny Frogmouth. CSIRO Publishing, 2007. http://dx.doi.org/10.1071/9780643095090.

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The tawny frogmouth is both intriguing and endearing. In this new book, well-known author Gisela Kaplan presents us with an easy-to-read account of these unique nocturnal birds of the Australian bush. This detailed account of life, behaviour and biology of tawny frogmouths is based on the most comprehensive single study ever conducted on tawny frogmouths, including wild and hand-raised birds. It combines ten years of systematic observation with published research to take us across a surprising range of characteristics and special features of this unusual bird. This book also notes insights derived from specific regional bird fauna surveys across Australia. We are shown this captivating Australian species in completely new and even unexpected ways. We learn that tawny frogmouths are very affectionate, have close bonds with lifelong partners, scream like prowling tomcats when distressed, fight with lightning speed and defend nest sites from reptilian predators by mobbing and spraying pungent faeces at these dangerous opponents. Uncompromising male fights are contrasted with a touching gentleness of males as fathers. We also learn how resilient and unusual tawny frogmouths are in the way they cope with heat and cold, sit out danger, do without drinking for most of their lives, and can use a large variety of food items. The developmental stages of nestlings and juveniles are illustrated with a number of stunning visual images accompanying the text, most of which have never before been described or seen.
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Buchteile zum Thema "Nocturnal bees"

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MacQuarie, Julius-Cezar. „The Researcher’s Nightworkshop: A Methodology of Bodily and Cyber-Ethnographic Representations in Migration Studies“. In IMISCOE Research Series, 293–313. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-67608-7_16.

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AbstractMigrants working the night shift (MWNS) have been invisible to the public eye for far too long. The failure to acknowledge the crucial role played by migrants working in the evening and night-time economy of developed societies is difficult to tackle with classical research tools alone. This chapter offers to novice and seasoned migration scholars a threefold methodological strategy to immerse, inhabit and to bring out of the dark a nocturnal landscape that has been invisible to diurnal people. The researcher’s nightworkshop’s innovative approach provides migration scholars with visual-analytical tools to capture the hidden experiences of MWNS. Theoretically, this chapter considers the broad aspects of representation (reel) and reality (real) of migrants in the public space and in migration scholarship. Night workers, the invisible people of the nocturnal city remain so to scholars, due to the impracticalities of doing nocturnal research (MacQuarie, 2019a). Empirically, therefore, the researcher’s nightworkshop’s strategy offers a solution to the puzzle of ‘invisibility’ of night shift workers. But it also reckons with the fact that to make visible the working lives in the realm of the night is a daunting task for scholars. Readers should interpret the notion of visibilisation with caution, using it as a visual metaphor to expose the factors that alter the night-shift workers’ precarious working conditions. This challenge is addressed here, through efforts that bridge the contingent of night workers, their minds and bodies that share the precarious landscape of nightwork with the researcher – alert and awake via the senses and suffering turned into skills.
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Narahari, Anoop, Raman Baweja, Piyush Das und Amit Chopra. „Eating Disorders“. In Management of Sleep Disorders in Psychiatry, herausgegeben von Amit Chopra, Piyush Das und Karl Doghramji, 511–30. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780190929671.003.0030.

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Sleep and eating behavior are complimentary homeostatic functions and adequate sleep is fundamental for the nutritional balance of the body. Short sleep duration has been linked to development of obesity and abnormal eating patterns in children and adults. Individuals with eating disorders report significantly higher sleep disturbances of sleep apnea, insomnia, circadian rhythm disorders, and impairment of daytime functioning, as compared to controls. Sleep disturbances have been implicated in suicidal behaviors in patients with eating disorders. This chapters outline the current evidence examining the pathophysiology and comorbidity of sleep disturbance in daytime eating disorders and focus on clinical assessment and management of nocturnal eating disorders including night eating syndrome and particularly sleep-related eating disorder, which is a combination of parasomnia and eating disorder. There is an imminent need to develop evidence-based pharmacological and psychological treatments for management of nocturnal eating disorders and the sleep disturbances associated with daytime eating disorders.
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Mar, Hugo Paz y., und Neal F. Chaisson. „Pulmonary Arterial Hypertension“. In Sleep Disorders, 884–96. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780190671099.003.0052.

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The high prevalence of pulmonary arterial hypertension (PAH) in patients with obstructive sleep apnea (OSA) and the putative pathophysiologic connections have been extensively documented. Conversely, patients with established PAH are at risk for sleep-related ventilatory instability, including OSA, central sleep apnea, and nocturnal desaturations. This chapter reviews the prevalence and pathophysiologic interactions of these conditions, the interplay with associated disorders, and the effects of continuous positive airway pressure therapy on pulmonary hemodynamics. In patients with OSA, chronic effects of repetitive hypoxia as well as comorbidities, including chronic obstructive pulmonary disease and left-sided heart dysfunction, play a role in promoting pulmonary hypertension. Sleep disordered breathing, representing a spectrum of sleep-related breathing disorders inclusive of OSA, is highly prevalent among patients with established pulmonary hypertension. Obstructive events, central sleep apnea, and nocturnal hypoxia are within the spectrum of sleep-related breathing disorders in pulmonary hypertension. The mechanisms for these associations remain speculative.
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Winnicott, Donald W. „Pathological Sleeping“. In The Collected Works of D. W. Winnicott, 149–50. Oxford University Press, 2016. http://dx.doi.org/10.1093/med:psych/9780190271336.003.0035.

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In this paper, Winnicott describes the case of a nine-year-old girl Brought to Queen’s Hospital for Children on account of falling asleep in the daytime. This had been a symptom since soon after tonsillectomy at the age of seven years. At the same time, she became very nervous at night-time and began to have nocturnal enuresis. When awake, she was lively, ate well, enjoyed playing games with her friends; at night, she would lie awake and knock until her mother came.
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Nunes, Michelle, Umesh Sharma, Nina Tsakadze, Lourdes Benes Lima, Mays Alani, Aqsa Ullah, Carlyn Rodriguez-Nazario, Joshua Rossi und Fabian Rossi. „Sleep Disorders and Epilepsy“. In Updates in Sleep Neurology and Obstructive Sleep Apnea [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.93989.

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Complex interplay and reciprocal interactions between sleep and epilepsy have been known for centuries. However, newer technologies and in-depth studies have provided us with better understanding of this relationship. Nocturnal seizures can interrupt sleep, while a number of factors, including antiepileptic drugs and sleep disorders, can aggravate seizures. Interestingly, different epileptic syndromes may trigger increase in seizure frequency at a certain phases of the sleep-wake cycle, while others may not show any correlation with these phases. We aim to provide an overview of the interactions between sleep and epilepsy, and provide better understanding how knowledge of the relationship between these two conditions can help more effective management of both disorders.
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Raines, James C. „Elimination Disorders“. In Evidence-Based Practice in School Mental Health, 340–56. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780190886578.003.0012.

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Elimination disorders are sometimes considered the ugly step-child in psychiatry. Nocturnal enuresis is the voiding of urine at night and is always involuntary. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) specifically mentions antipsychotic medications as a potential cause. Encopresis is the repeated elimination of feces into inappropriate places, whether voluntary or involuntary. All children with elimination problems should see a pediatrician to rule out medical/physical causes. The prevalence of enuresis has been found to be higher in large or crowded families or in families that practice co-sleeping. A multitiered system of support approach begins with good toilet training and addresses occasional accidents. Simple behavioral treatments can usually resolve the problems. A case example illustrates a typical case.
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Kirsch, Douglas B., und Lawrence J. Epstein. „Sleep Apnea“. In The Brigham Intensive Review of Internal Medicine, 356–65. Oxford University Press, 2014. http://dx.doi.org/10.1093/med/9780199358274.003.0035.

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More has been learned about sleep in the last 60 years than in the preceding 6000 years, to paraphrase one sleep researcher, and sleep apnea is an area in which knowledge growth has been particularly exponential. In the last several decades, sleep specialists have learned how to study sleep, subdividing it into stages based on the sleep-related changes in the electroencephalogram (EEG), eye movements, and muscle tone. Additional measurements of airflow, respiratory effort, limb muscle movements, electrocardiogram (EKG), and oxygen saturation allow a full characterization of the changes and problems that occur during sleep. The process of studying physiological parameters during sleep, called polysomnography, has allowed sleep specialists to better understand the nocturnal rhythms of sleep and identify disruptors, one of the most common being obstructive sleep apnea (OSA). This chapter covers the epidemiology, pathophysiology, evaluation, and treatment of this common chronic disorder and its significant long-term effects on patient's well-being and health.
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Walker, Matthew C. „Narcolepsy“. In Oxford Textbook of Medicine, herausgegeben von Christopher Kennard, 5882–86. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198746690.003.0576.

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Narcolepsy with cataplexy is a specific syndrome of daytime sleepiness, disrupted nocturnal sleep, and episodes of sudden loss of muscle tone—provoked by the anticipation of emotions (in particular laughter)—leading to a tendency to fall, mouth opening, dysarthria or mutism, and facial muscle jerking. It is associated with loss of hypocretin (orexin) neurons in the hypothalamus, hypocretin concentrations in the cerebrospinal fluid below 110 pg/ml, and the HLA genotype DQ B1*0602. A less common form of narcolepsy without cataplexy probably has a different, as yet unknown, pathogenesis. Once established, narcolepsy is lifelong; spontaneous recovery does not occur. Symptomatic treatment—which is essential for school performance, work, driving ability, and quality of life—is with stimulant (e.g. amphetamine) and anticataplectic (e.g. clomipramine) drugs. More recently, sodium oxybate, an anaesthetic, has been used to induce deep sleep overnight, resulting in improvements in all symptoms.
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Shelleg, Assaf. „Horizontal Realizations“. In Theological Stains, 93–198. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780197504642.003.0003.

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If the actualization of biblical sovereignty in the Zionist present rendered eighteen centuries of exile a nocturnal existence, art music of the 1950s and 1960s interfered with such linearity using the linear properties of non-Western Jewish musical traditions and serial compositional devices. Such a convergence rendered the objectification of non-Western Jewish musical traditions obsolete and consequently severed the exotic and territorial functions they served. By utilizing the linear properties of Arab Jewish musical traditions to animate inner semiotic occurrences, composers suspended extrovert exotic signifiers and invalidated their objectification. With no visible exoteric earmarks to transmit peripherality and Otherness, the binaries by which non-European Jewish immigrants had been perceived (primitivism/modernism, religion/secularism) were deemed progressively inoperative. Through a study on the agency of non-European Jewish musical traditions, chapter 2 uncovers the network that connects the theological grammar of Zionism with the Zionist pecking order, whose lower rungs were allocated to North African and Near Eastern Jews.
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Sharpe, Claire C. „Sickle cell disease and the kidney“. In Oxford Textbook of Medicine, herausgegeben von John D. Firth, 5032–34. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198746690.003.0497.

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About 60% of patients with sickle cell disease have sickle cell nephropathy. Clinical symptoms reflect medullary compromise, with polyuria, troublesome nocturia, enuresis, and dehydration being typical early manifestations. Haematuria, nonvisible and visible, is common. The prevalence of albuminuria rises with age, and those in whom this progresses rapidly are at greatest risk of developing endstage kidney disease, which eventually affects 10 to 15% of patients with sickle cell nephropathy. Management of chronic kidney disease due to sickle cell nephropathy is along standard lines: no specific treatment has been shown to prevent the condition or retard its progression.
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Konferenzberichte zum Thema "Nocturnal bees"

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Waltisberg, Daniel, Oliver Amft und Gerhard Tröster. „Accuracy-coverage tradeoff of nocturnal vital sign estimation in smart beds“. In UbiComp '14: The 2014 ACM Conference on Ubiquitous Computing. New York, NY, USA: ACM, 2014. http://dx.doi.org/10.1145/2638728.2638810.

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Morrison, J. EJ, A. B. Latif, C. Mason, P. Bramley und T. R. Criag. „THE PROFILE OF IN VIVO PLATELET ACTIVATION IN NOCTURNAL ASTHMA“. In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643495.

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The precise pathophysiology of nocturnal asthma still remains to be elucidated. Activated platelets have the ability to release potent broncho- and vaso-constrictors and therefore, have been implicated in asthma. However, there is no information on the status of in vivo platelet activation in patients with nocturnal asthmaIn a randomised controlled study five healthy volunteers and five asthmatics were investigated during a period of 24h after acclimatisation for one day. Both peak flow rate (PFR) and blood samples were obtained at 4 hourly intervals. Plasma levels of platelet factor 4 (PF4) and beta- thromboglobulin(BTG) were measured by radioimmunoassay and adrenaline (A), noradrenaline (NA) and dopamine (DOP) by radioenzymatic analysis.PFR (1/min) for the 24h period was significantly lower in asthmatics (401±15SEM, P<0.001) than in controls (598+4SEM) with an apparent circadian rhythm peak (442±73, P<0.05 Wilcoxon's test) at 4.00pm only in asthmatics. Although there was no significant differences in either PF4 and BTG (ng/ml) or A, NA and DOP (nmol/1) between asthmatics and controls an apparent circadian rhythm in all of these parameters was demonstrated in both groups. Peak values (mean+SEM) for PF4 (8.9±1.5) and BTG (44.4±3.8) occurred at 8.00am whereas the highest values for the catecholamines (A: 0.36±0.08, NA: 1.75±0.23, DOP: 0.78±0.16) were observed at 4.00pm indicating a lag of 8h between the peaks for catecholamines and the platelet specific proteinsThese initial data demonstrate a clear difference in PFR between asthmatics and controls which is apparently not associated with changes in either PF4 or BTG but which may concur with circadian changes in plasma levels of catecholamines at least in asthmatic patients. Thus, in vivo platelet activation is probably not a contributing factor in nocturnal asthma. Finally, the phase lag between peak plasma levels of platelet proteins and catecholamines requires further investigation
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Gulba, D., und P. Lichtlen. „FOUR CASES WITH STABILIZATION OF UNSTABLE ANGINA PECTORIS BY THROMBOLYTIC THERAPY“. In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643007.

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Acute myocardial infarctions in the vast majority of cases are caused by coronary artery thrombosis at the site of complicated arteriosclerotic plaques. By several trials evidence has been given, that myocard can be preserved, when thrombolytic therapy is started within a short period after thrombotic coronary occlusion. Recently, angioscopic evidence has been given, that the unstable angina pectoris syndrome frequently is assciated with coronary artery thrombosis, too. Thus, thrombolytic therapy should be of comparable benefit for patients suffering from unstable angina pectoris syndrome. Up to now, we have treated four patients suffering from unstable angina pectoris syndrome (two with documented spontaneous reversible ST-segment elevations, two with newly complained recurrent nocturnal episodes of severe angina) with thrombolytic therapy (Pat. 1: 1.5 Mio IE Streptokinase; Pat. 2: 100 mg rt-PA; Pat. 3: 150 mg rt-PA; Pat. 4: 60 mg scu-PA plus 200 000 IE UK). After thrombolytic therapy, all four patients were free of symptoms for at least 60 h. Pat. 3 had recurrance of chest pain with spontaneous reversible ST-segment elevations on the third day after therapy. Pat. 1, 2, and 4 were without clinical symptoms until angiography and secondary intervention (angioplasty (PTCA) /bypass operation (CABG)). Cardiac catheterization was performed within one week after thrombolytic therapy. In all four patients, ischemia related coronary artery was patent at angiography. We conclude, that in unstable angina pectoris syndromes with newly developed nocturnal symptoms and/or spontaneous reversible ST-segment elevations in the ECG can be stabilized by thrombolytic therapy. After thrombolysis, however, recurrance of chest pain may be soon, and PTCA or CABG should be performed as soon as possible.
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Shafer, Michael W., und Eric Morgan. „Energy Harvesting for Marine-Wildlife Monitoring“. In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7630.

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Bio-logging devices are systems mounted to an animal that measure parameters associated with the animal or its environment. These devices date back to the 1930’s in their simplest form, while modern devices use suites of digital sensors, microcontrollers, and wireless data communication. Despite these advances, there has always been a fundamental relationship between power consumption and the amount of science that can be conducted. There are now a number of commercially available devices that use solar cells to supplement their daily energy budget, but supplemental solar power is not useful for species that are nocturnal, subterranean, aquatic, or spend significant time beneath dense forest canopies. As such, there have been calls from the marine biology community for devices that could harvest power from their environments. For these marine species, alternative energy harvesting techniques are required. Here we explore a new application for energy harvesting as a power source for marine wildlife bio-logging tags. Marine animals cover wide swaths of the ocean, making tracking and data collection challenging. Tagging these animals with devices that track their location and/or collect data about the animal or its surroundings require large batteries and have limited life spans due to high power requirements for satellite data relays. With limited solar irradiance at depth making solar power less attractive, we review and explore other forms of energy that could be harvested, such as energy from fluid flow and hydrostatic pressure cycles. We investigate the energy potential from a number of sources and compare these values with the requirements of current bio-logging systems to assess required transduction efficiencies. The application of energy harvesting on animal tags could result in nearly indefinite life systems allowing for data collection from a single animal over the course of many years.
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Devine, D. V., und W. F. Rosse. „PLATELET FACTOR H REGULATES THE ACTIVITY OF THE ALTERNATIVE PATHWAY OF COMPLEMENT ON THE SURFACE OF NORMAL AND PAROXYSMAL NOCTURNAL HEMOGLOBINURIA PLATELETS“. In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643979.

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Paroxysmal nocturnal hemoglobinuria (PNH)-is frequently complicated by thrombosis. It has been suggested that the abnormal interactions of PNH platelets with complement contribute to thrombosis. Using purified complement proteins, we have previously demonstrated that the platelets from some patients with PNH do not demonstrate elevated activity of C3bBb, the alternative pathway C3 amplification enzyme complex, even though they lack the C3bBb regulatory protein, decay accelerating factor (DAF). As measured by fluorescence flow cytometry, washed platelets from both normal donors and PNH patients released the fluid phase C3bBb regulatory protein, factor H, in response to the deposition of purified complement proteins. Platelet factor H was localized to the alpha granules by immunocytochemical techniques. A quantitative radioimmunoassay demonstrated that normal platelets released 54 ± 6 ng factor H/108 platelets in response to thrombin stimulation. PNH platelets contained less factor H (22 ±7 ng/108 platelets) than normal platelets. Thrombin stimulated platelets from patients with elevated C3bBb activity released less than half of the factor H measured in detergent extracts. However, thrombin stimulated platelets from PNH patients exhibiting normal C3bBb activity released nearly all their factor H. The release of factor H from normal platelets was blocked by treating the platelets with metabolic inhibitors. In the absence of factor H release, the activity of the C3bBb complex increased three-fold. In addition, the number of molecules of 1251-factor B bound per C3b increased from 0.40 to 0.92 when factor H release was blocked. The inhibition of DAF by anti-DAF had no effect on the activity of C3bBb if factor H could be released from the platelets. However, when factor H release was blocked by treatment with metabolic inhibitors, the inhibition of DAF by anti-DAF increased the activity of C3bBb by 40%. Therefore, in the absence of DAF, platelets can regulate complement activation by the alternative pathway via the release of platelet factor H. Since factor H is an alpha granule protein, platelet release in the presence of activated complement may contribute to the occurrence of thrombosis.
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Orecchini, Fabio, Federico Villatico Campbell und Adriano Alessandrini. „The HOST Vehicle Concept: Human Oriented Sustainable Transport“. In ASME 2005 3rd International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2005. http://dx.doi.org/10.1115/fuelcell2005-74072.

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HOST is an innovative vehicle concept suitable for the urban transport of both persons and goods. To lower the impact of mobility on the cities, cleaner vehicles are not enough: an integrated passenger and freight strategy must be adopted. Cleaner vehicles must be specifically designed for the purpose to be better than conventional ones under any aspect, including costs. To lower such costs and to start up the Low Polluting Vehicles (LPV) market the versatility of LPVs has to be enhanced. HOST aims at developing a fully versatile low-cost LPV concept. Versatility is achieved by making HOST vehicle modular and cost reduction is obtained by using the same vehicle for different purposes, simply changing different cabins on the same chassis. The main four tasks HOST is conceived for are: • Nocturne collective taxi; • Daytime car sharing services; • Daytime freight collection and distribution; • Nocturne garbage collection. The four mentioned services are not the only ones HOST may be used for, but are those for which it is specifically studied. Such choice is made for one very simple reason: all of the four tasks belong to the same family of “municipal services”. Using the same chassis to operate all the different services is feasible and can finally create the critical mass of final users, so to reach convenient prices. The four services chosen, two addressing passenger mobility and two addressing freight mobility, go all in the way of reducing city mobility impact. Car sharing and nocturne collective taxi systems, if integrated with public transport, can increase its attractiveness, pushing more people to use it. Freight pick-up and delivery and garbage collection need a low polluting alternative to be re-organised, so to become sustainable. The powertrain layout and the possibility to easily vary the platform main dimensions enable HOST to be equipped with very different bodyworks, which let the car manufacturer provides both private and public bodies, such as municipalities or urban mobility authorities. More in detail the energy system is all included in the HOST platform and it is conceived in shaped boxes, so that its modules become inter-exchangeable. A series hybrid configuration let HOST to be equipped with an internal combustion engine (ICE) coupled with an energy recovery system (batteries+supercapacitors), anyhow is already designed to utilise fuel cells (FC) powered by pure hydrogen just changing the energy module (and the tank), being this last the final purpose of the concept design. Thanks to these two solutions HOST is able to run as a zero emission vehicle for a limited period (ICE) or for the whole driving cycle (FC). A full drive-by-wire solution is adopted and the only mechanical connections between the cabin and the platform will be a specifically designed mechanical anchorage, these solutions will allow the easy installation/removal of any cabin. The vehicle has four wheel drive capability (4WD), thus featuring a good grip even on slippery roads. The four electric motors (one per wheel) allow an easy traction control, ensuring stability and safety. The chassis has a four wheel total steering (4WS) configuration, that enables the vehicle to rotate around its vertical axis as well as the to shift horizontally. These characteristics give HOST decisive advantages for the missions it has been conceived for. The 4WS capability gives to the vehicle easy manoeuvring in little streets in the cities centres and they are useful for the accurate positioning to be easily accessible by wheel chairs, during freight loading/unloading operations and while it runs as a garbage truck. Only a modular vehicle featuring the reusing concept can cover contemporarily all the selected services: one vehicle chassis with different sizes interchangeable energy generation modules and different bodies, depending on the service it is used for. Such concept, other than abating the environmental impact, will allow: • a reduction of costs: one chassis can fit several bodies compensating the higher cost of a low environmental impact energy and traction system; • a reduction of occupied space: the vehicle is always in use, night and day; • a reduction of waste materials, increasing their lifetime; • an increased life of vehicles, due to the possibility of changing bodies and energy generation modules; • traffic congestion reduction: using and reusing one vehicle for several services.
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Zavrel, Erik A., und Matthew R. Ebben. „An Active Distal Limb Warming Device for Insomnia Treatment“. In 2017 Design of Medical Devices Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/dmd2017-3469.

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The defining characteristics of insomnia are widely recognized as difficulty falling asleep, difficulty staying asleep, and sleep that is non-restorative [1]. Insomnia is among the most common health complaints: about 10% of the adult population complains of a chronic insomnia problem [2]. With aging, increasingly disturbed sleep and less satisfaction with sleep quality are reported [3]. This common problem has wide ranging physiological, cognitive, and behavioral consequences including higher healthcare utilization [4–6]. Current major treatment options for insomnia (hypnotic medications and non-pharmacological behavioral interventions) suffer side effects and shortcomings. Thermoregulation plays a key role in promoting and maintaining sleep. At night, core body temperature (CBT) drops while distal skin temperature (DST) increases. It was previously believed that the nighttime drop in CBT was the most important promoter of sleep. However, recent research has shown that it is in fact the increase in DST (with net body heat loss owing to the large distal skin surface area) which is associated with an increase in sleepiness, whereas a decrease in DST (with resulting net body heat retention) is associated with a decrease in sleepiness [7]. The amount of distal vasodilation, as measured by the distal-proximal skin temperature gradient (DPG), is more predictive of sleep onset than subjective sleepiness ratings, CBT, or dim light melatonin onset. In fact, “the degree of dilation of blood vessels in the skin of the hands and feet, which increases heat loss at these extremities, is the best physiological predictor for the rapid onset of sleep” [8]. The link between distal skin warming and sleep propensity is further strengthened by the fact that warm water immersion of hands and feet has been found to decrease sleep onset latency (SOL) and pre-sleep warm baths have long been prescribed as an insomnia treatment. In a recent study, we used a multiple sleep latency test (MSLT) to perform multiple nap trials throughout the day, with the participants’ hands and feet immersed in warm water prior to each nap. We found that both mild and moderate warming of the hands and feet prior to a nap significantly reduced SOL compared to a baseline MSLT without warming [9]. We also previously conducted a trial of temperature biofeedback for insomnia treatment in which we demonstrated SOL reduction using muscle relaxation techniques to induce distal vasodilation, increase blood flow to the extremities, and modulate temperature of hands and feet [10]. Additionally, it has been shown that regardless of circadian variation throughout the day, finger temperature shows a rapid increase immediately before sleep onset [11]. Lastly, people with primary vascular dysregulation (a condition caused by abnormal vasoconstriction that results in cold hands and feet) exhibit significantly increased SOL and greater difficulty falling asleep following nocturnal arousal [12]. Thus, some presentations of insomnia may be secondary to distal vasodilation failure. The motivation for an active distal limb warming device as a treatment for insomnia is based on the established functional link between distal vasodilation and sleep induction [13]. Somewhat counterintuitively then, heating of hands and feet can induce distal vasodilation, promote net body heat loss, and facilitate sleep onset [14, 15].
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