529 research outputs found
On the Evolution and Inheritance of Farming Culture in Southwest Ethnic Minority Areas
Farming culture in southwest ethnic minority area is an important part of the whole Chinese farming culture. The unique natural conditions, ethnic structure and production features in southwest ethnic minority area have bred a special value of farming culture, making it play a significant role in protecting the environment and promoting ethnic harmony and regional development. Modernization has dramatically changed the environment for the evolution of farming culture. We must concise and develop the core concept and based on protection and inheritance to reasonably develop and utilize it to realize its value and promote its development
The greatest Ricci lower bound, conical Einstein metrics and the Chern number inequality
We partially confirm a conjecture of Donaldson relating the greatest Ricci
lower bound to the existence of conical Kahler-Einstein metrics on a
Fano manifold . In particular, if is a smooth simple divisor
and the Mabuchi -energy is bounded below, then there exists a unique conical
Kahler-Einstein metric satisfying for any
. We also construct unique smooth conical toric
Kahler-Einstein metrics with and a unique effective Q-divisor
for all toric Fano manifolds. Finally we prove a Miyaoka-Yau type
inequality for Fano manifolds with
Asymmetric synthesis of gonytolide A: strategic use of an aryl halide blocking group for oxidative coupling
The first synthesis of the chromanone lactone dimer gonytolide A has been achieved employing vanadium(V)-mediated oxidative coupling of the monomer gonytolide C. An o-bromine blocking group strategy was employed to favor para- para coupling and to enable kinetic resolution of (±)-gonytolide C. Asymmetric conjugate reduction enabled practical kinetic resolution of a chiral, racemic precursor and the asymmetric synthesis of (+)-gonytolide A and its atropisomer.We thank the National Institutes of Health (R35 GM-118173) for research support. Work at the BU-CMD is supported by NIH R24 Grant GM-111625. We thank Prof. Scott Miller and Dr. Anthony Metrano (Yale University) for helpful discussions and preliminary experiments. We thank the Uehara Memorial Foundation for a postdoctoral fellowship to T.I., the American Cancer Society for a postdoctoral fellowship to K.D.R. (PF-16-235-01-CDD), Dr. Jeffrey Bacon (Boston University) for X-ray crystal structure analyses, and Prof. Haruhisa Kikuchi (Tohoku University) for providing a natural sample of gonytolide A. NMR (CHE-0619339) and MS (CHE-0443618) facilities at Boston University are supported by the NSF. (R35 GM-118173 - National Institutes of Health; GM-111625 - NIH; Uehara Memorial Foundation; PF-16-235-01-CDD - American Cancer Society; CHE-0619339 - NSF; CHE-0443618 - NSF
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