نتایج جستجو برای: protected conditions

تعداد نتایج: 897603  

Journal: :Chemical communications 2003
Alberto Avenoza Jesús H Busto Noelia Canal Jesús M Peregrina

The reactivity of 2-acylaminoacrylates with ketene diethyl acetal can be modulated by means of thermal conditions to yield cyclobutanes for the preparation of protected beta-hydroxycyclobutane-alpha-amino acids, or catalytic conditions that yield cyclohexanes by tandem condensations to obtain interesting building blocks that are alternatives to Danishefsky's diene.

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2011
Charles B Yackulic Eric W Sanderson María Uriarte

The extinction of a species is inevitably preceded by the extirpation of a series of local populations. Ecological theory predicts that vulnerability to extirpation varies between populations and is ultimately linked to environmental heterogeneity. If populations of a species are present in multiple regions separated by abrupt changes in environmental conditions (e.g., biomes), spatial variatio...

Journal: :The Journal of neuroscience : the official journal of the Society for Neuroscience 1995
P J Vaughan C J Pike C W Cotman D D Cunningham

Thrombin is a multifunctional serine protease that is rapidly produced from prothrombin at sites of tissue injury and catalyzes the final steps in blood coagulation. Thrombin also regulates gene expression and process outgrowth in neurons and astrocytes and stimulates proliferation of astrocytes. Since thrombin is produced immediately upon breakdown of the blood-brain barrier we examined its ef...

ژورنال: :نشریه محیط زیست طبیعی 2010
یگانه سپاسی افشین دانه کار افشین علیزاده علی اصغر درویش صفت رزیتا شریفی پور

ecotourism is known as a type of sustainable tourism which helps both conservation and development, but many of tourism sites go to instability and self-destruction because of unsuitable environment assessment. besides it is necessary to introduce new region for increasing of protected area in iran. using related criteria is an appropriate method for selection of suitable protected area and eco...

Introduction: Rangelands constitute almost 52 percent of the country area computed as 164 million ha. The extent of rangelands has been estimated 84 million ha in Iran and they have been classified as good, moderate to poor and poor to very poor ones ranged as almost 10, 42 and 48 percent, respectively. One of the fundamental problems concerning land uses of rangelands is that Rangeland are not...

Journal: :محیط زیست طبیعی 0
آزاده مهری کارشناس ارشد محیط‏زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان عبدالرسول سلمان ماهینی دانشیار گروه محیط‏زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان سید حامد میرکریمی استادیار گروه محیط‏زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان حمیدرضا رضایی استادیار گروه محیط‏زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان

to preserve wildlife habitats and populations, it is normal practice to select representative natural areas. the aim of this research is prioritization of candidate sites for environmental protection in mazandaran province. for this purpose, 26 forest cover types, habitats of 8 mammal species and important distribution areas for 4 groups of birds were used as input criteria. simulated annealing...

پایان نامه :دانشگاه آزاد اسلامی - دانشگاه آزاد اسلامی واحد تهران مرکزی - دانشکده ادبیات و علوم انسانی 1390

abstract birbery and corruption and other criminal and as such is one of social phenomena , and i can firmly say that society is protected and safe from harm , this is criminal . eache community is familiar with these crimes and the crime associated ( direct or indirect ) with the political economic , social , and cultural beliefs and religious issues , especially with the community . admitted...

Journal: :Bulletin of the Bureau of Standards 1916

2012
Alexei Czeskis Dirk Balfanz

Despite known problems with their security and ease-of-use, passwords will likely continue to be the main form of web authentication for the foreseeable future. We define a certain class of password-based authentication protocols and call them protected login. Protected login mechanisms present reasonable security in the face of real-world threat models. We find that some websites already emplo...

Journal: :Nucleic acids research 2002
Sergey N Mikhailov Jef Rozenski Ekaterina V Efimtseva Roger Busson Arthur Van Aerschot Piet Herdewijn

The base moiety of 1-N-methyladenosine can be protected with a chloroacetyl group for incorporation of this modified nucleoside into DNA and RNA. Carefully controlled anhydrous conditions are needed for deprotection of the oligonucleotides.

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید