University of New Mexico

About: University of New Mexico is a education organization based out in Albuquerque, New Mexico, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 28870 authors who have published 64767 publications receiving 2578371 citations. The organization is also known as: UNM & Universitatis Novus Mexico.

Stable DNA replication: interplay between DNA replication, homologous recombination, and transcription.

Abstract: Chromosome replication in Escherichia coli is normally initiated at oriC, the origin of chromosome replication. E. coli cells possess at least three additional initiation systems for chromosome replication that are normally repressed but can be activated under certain specific conditions. These are termed the stable DNA replication systems. Inducible stable DNA replication (iSDR), which is activated by SOS induction, is proposed to be initiated from a D-loop, an early intermediate in homologous recombination. Thus, iSDR is a form of recombination-dependent DNA replication (RDR). Analysis of iSDR and RDR has led to the proposal that homologous recombination and double-strand break repair involve extensive semiconservative DNA replication. RDR is proposed to play crucial roles in homologous recombination, double-strand break repair, restoration of collapsed replication forks, and adaptive mutation. Constitutive stable DNA replication (cSDR) is activated in mhA mutants deficient in RNase HI or in recG mutants deficient in RecG helicase. cSDR is proposed to be initiated from an R-loop that can be formed by the invasion of duplex DNA by an RNA transcript, which most probably is catalyzed by RecA protein. The third form of SDR is nSDR, which can be transiently activated in wild-type cells when rapidly growing cells enter the stationary phase. This article describes the characteristics of these alternative DNA replication forms and reviews evidence that has led to the formulation of the proposed models for SDR initiation mechanisms. The possible interplay between DNA replication, homologous recombination, DNA repair, and transcription is explored.

Nitrate Losses from Disturbed Ecosystems

Abstract: A systematic examination of nitrogen cycling in disturbed forest ecosystems demonstrates that eight processes, operating at three stages in the nitrogen cycle, could delay or prevent solution losses of nitrate from disturbed forests An experimental and comparative study of nitrate losses from trenched plots in 19 forest sites throughout the United States suggests that four of these processes (nitrogen uptake by regrowing vegetation, nitrogen immobilization, lags in nitrification, and a lack of water for nitrate transport) are the most important in practice The net effect of all of these processes except uptake by regrowing vegetation is insufficient to prevent or delay losses from relatively fertile sites, and hence such sites have the potential for very high nitrate losses following disturbance

Energy loss and flow of heavy quarks in Au+Au collisions at sNN=200GeV

Abstract: The PHENIX experiment at the BNL Relativistic Heavy Ion Collider (RHIC) has measured electrons with 0.3 < p(T) < 9 GeV/c at midrapidity (y < 0.35) from heavy-flavor (charm and bottom) decays in Au + Au collisions at root s(NN) = 200 GeV. The nuclear modification factor R-AA relative to p + p collisions shows a strong suppression in central Au + Au collisions, indicating substantial energy loss of heavy quarks in the medium produced at RHIC energies. A large azimuthal anisotropy v(2) with respect to the reaction plane is observed for 0.5 < p(T) < 5 GeV/c indicating substantial heavy-flavor elliptic flow. Both R-AA and v(2) show a p(T) dependence different from those of neutral pions. A comparison to transport models which simultaneously describe R-AA(p(T)) and v(2)(p(T)) suggests that the viscosity to entropy density ratio is close to the conjectured quantum lower bound, i.e., near a perfect fluid.

Geographic variation in the treatment of localized breast cancer.

Abstract: Background. Breast-conserving surgery followed by radiation therapy is as effective as modified radical mastectomy in treating women with localized breast cancer, as demonstrated by clinical trials reported during the 1980s. The extent to which breast-conserving surgery has been adopted in various regions of the United States is not known. Methods. We assessed variations in the use of breast-conserving surgery from 1983 to 1986 in 18,399 non-Hispanic white, 324 Hispanic, and 1174 black women with breast cancer in nine areas of the United States, using data from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute. Results. The proportion of white women with localized breast cancer who underwent breast-conserving surgery ranged from 9.2 percent (Iowa) to 32.1 percent (Seattle) in 1983–1984 and from 19.6 percent (Iowa) to 41.5 percent (Seattle) in 1985–1986. Between 1983 and 1986, the use of breast-conserving surgery increased in each area, but the relative ranki...