Pellaea atropurpurea (L.) Link and Pellaea glabella Mett. ex Kuhn

ریخت شناسی هاگ سرخس Cheilanthes persica (Bory) Mett. ex Kuhn. و مراحل نموی آن

Cheilanthes persicaیکی از سرخس‌های رستاخیزی است که در طول تنش خشکی کاملاً خشک و بعد از آبیاری احیا می­شود. این نمونه از کرمانشاه (طاق بستان، غرب ایران) جمع‌آوری و در اتاق رشد کشت و چرخه زندگی آن مورد بررسی قرار گرفت. هاگ به حالت تتراد چهارگوشه‌ای با تزیینات مشبک ریز ناپیوسته است.

Detection of members of the Tombusviridae in the Tallgrass Prairie Preserve, Osage County, Oklahoma, USA.

Viruses are most frequently discovered because they cause disease in organisms of importance to humans. To expand knowledge of plant-associated viruses beyond these narrow constraints, non-cultivated plants of the Tallgrass Prairie Preserve, Osage County, Oklahoma, USA were systematically surveyed for evidence of the presence of viruses. This report discusses viruses of the family Tombusviridae...

Kuhn and Scientific Practices

Joseph Rouse Wesleyan University Thomas Kuhn's philosophical work has helped initiate or reinvigorate many of the central themes in the philosophy of science over the past three decades. His claim that appropriate attention to history could decisively transform familiar philosophical of science views was of course prophetic. Kuhn's discussion of meaning change, incommensurability, and the inter...

Gödel, Kuhn, and Feyerabend

Thomas Kuhn [4] has presented a view of the history of science as a succession of “paradigms” which are not completely comparable with each other. Karl Popper [8] has attacked this view as being relativistic and denying that there is objective scientific truth. Popper seems to be saying that in order for science to be objectively true, every two scientific theories must be completely comparable...

Kuhn and Philosophy