نتایج جستجو برای: seasonal change

تعداد نتایج: 650005  

پایان نامه :دانشگاه تربیت معلم - تهران - دانشکده علوم انسانی 1390

به منظور شناسایی تغییر اقلیم در ایران، الگوهای فشار سطوح بالای جوی مطالعه شد. ابتدا با استفاده از داده های ارتفاعی روزانه سه سطح عمده جوی 500، 700 و 850 هکتوپاسکال در دوره 1948-2010 برای محدوده 10 تا 70 درجه شمالی و 10 تا 80 درجه شرقی، مراکز فعالیت شناسایی شدند. روش تحلیل مولفه های اصلی برای تعیین مراکز فعالیت استفاده شد. نتایج نشان داد 7 مولفه عمده با یکدیگر نزدیک به 90 درصد واریانس را توجیه م...

The aim of this research is the study of the climate change impacts on the seasonal and annual reference evapotranspiration time scales in some selected stations located in the West of Iran. To this purpose, four stations including Sanandaj, Saghez, Khorramabad and Kermanshah synoptic stations with enough long-term data were selected and the climate change impact on the reference evapotranspira...

Journal: :Journal of voice : official journal of the Voice Foundation 2008
Eva Millqvist Mats Bende Moa Brynnel Inger Johansson Sofi Kappel Ann-Christine Ohlsson

Voice problems are seldom reported in pollen allergy, although the allergic reaction involves the entire airways. The objective of this study was to investigate voice dysfunction during the pollen season in patients with allergic rhinitis. Thirty patients with verified birch pollen allergy and 30 controls were investigated twice, during the pollen season and outside the pollen season. Both time...

Journal: :Philosophical transactions of the Royal Society of London. Series B, Biological sciences 2009
F H Bronson

Seasonal reproduction is common among mammals at all latitudes, even in the deep tropics. This paper (i) discusses the neuroendocrine pathways via which foraging conditions and predictive cues such as photoperiod enforce seasonality, (ii) considers the kinds of seasonal challenges mammals actually face in natural habitats, and (iii) uses the information thus generated to suggest how seasonal re...

Journal: :Science 1975
A L Gordon H W Taylor

The winter expansion of the sea ice surrounding Antarctica and the subsequent retreat of the ice in summer may be linked with the wind stress acting on the Southern Ocean in conjunction with the heat exchange in open water regions within the ice fields.

Journal: :Behavioural processes 2009
David F Sherry Jennifer S Hoshooley

Food storing is seasonal in birds like chickadees, nuthatches and jays, occurring at high levels in fall and winter and low levels in spring and summer. Memory for cache sites is hippocampus dependent in chickadees and both the recruitment of new neurons into the hippocampus and the total size of the hippocampus change seasonally. Unlike seasonal change in the vocal control nuclei of songbirds,...

Journal: :Archives of general psychiatry 2001
T A Wehr W C Duncan L Sher D Aeschbach P J Schwartz E H Turner T T Postolache N E Rosenthal

BACKGROUND In animals, the circadian pacemaker regulates seasonal changes in behavior by transmitting a signal of day length to other sites in the organism. The signal is expressed reciprocally in the duration of nocturnal melatonin secretion, which is longer in winter than in summer. We investigated whether such a signal could mediate the effects of change of season on patients with seasonal a...

Journal: :Advances in genetics 2017
William E Bradshaw Christina M Holzapfel

Seasonal change in the temperate and polar regions of Earth determines how the world looks around us and, in fact, how we live our day-to-day lives. For biological organisms, seasonal change typically involves complex physiological and metabolic reorganization, the majority of which is regulated by photoperiodism. Photoperiodism is the ability of animals and plants to use day length or night le...

Journal: :Philosophical Transactions of the Royal Society B: Biological Sciences 2009

2011
ADAM H. SOBEL SUZANA J. CAMARGO

The authors analyze changes in the tropical sea surface temperature (SST), surface wind, and other fields from the twentieth to the twenty-first century in climate projections using the Coupled Model Intercomparison Project phase 3 (CMIP3) multimodel ensemble, focusing on the seasons January–March (JFM) and July–September (JAS). When the annual mean change is subtracted, the remaining ‘‘seasona...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید