4,504 research outputs found
Genetic incorporation of D-Lysine into diketoreductase in Escherichia coli cells
D-Lysine has been genetically introduced into diketoreductase in E. coli cells by utilization of an orthogonal Ph tRNA /Lysyl-tRNA synthetase pair. This is the first report on the genetic incoporation of D-amino acids into proteins, which may be generally applicable to a wide variety of applications
RODENT CONTROL IN CHINA
Rodent pest problems and their control in China are reviewed. Three commensal species, Rattus norvegicus, R. flavipectus and Mus musculus, are important pests both in urban and rural regions. Mus musculus is the most widely distributed species in China. Its population density is cyclic, unique for a commensal species in being found in the arid Xinjiang (Sinkiang) Autonomous Region in Northwest China. In South China, R. losea and Bandicota indica are serious problems in rice and cane fields. Many different genera of field rodents are considered pests to agriculture and/or are reservoirs of rodent-borne diseases. These include Citellus, Marmota, Meriones, Cricetulus, Microtus, Apodemus, Ochotona, Myospalax, Clethrionomys, Sciurus, and Eutamias. The ecology and control of these rodents are included. There are a series of efficient administrative organizations responsible for rodent control. Most campaigns of commensal rodents have relied on a combination of rodenticides and different types of traps, but in the case of field rodents the reliance is heavily placed on poison baits. Diphacinone (Na-salt) is most frequently used for control of commensal species. Zinc phosphide, fluoroacetimide (1081), sodium fluoroacetate (1080), glyftor and 0.2% diphacinone (Na-salt) are used for field rodent control. Information is supplied on the susceptibility of important rodents in China to different rodenticides, including difenacoum and brodifacoum, and on other means of rodent control
The fully-light vector tetraquark states with explicit P-wave via the QCD sum rules
In this article, we apply the QCD sum rules to study the vector fully-light
tetraquark states with an explicit P-wave between the diquark and antidiquark
pair. We observed that the
type current with fully-strange quarks couples potentially to a tetraquark
state with a mass , which supports assigning the
as the diquark-antidiquark type tetraquark state with the
. The and vector
tetraquark states with the structure are consistent with the and
respectively, which lie in the region to . The central
values of the masses of the fully-strange vector tetraquark states with an
explicit P-wave are about , the predictions for other
fully-light vector tetraquark states with and without hidden-strange are also
presented.Comment: 12 pages, 16 figure
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