Understanding and managing nutrient pollution in peri-urban wetlands: The Ciénegas del Lerma, Mexico.

Nutrient pollution has been broadly studied in developed countries, where the primary source is often agricultural diffuse pollution. However, more research is needed in developing countries with a predominance of low-income households, insufficient public service infrastructure, pressure from urban expansion, and scarce information. In this research, centered on the Lerma Cienega protected wetlands in a peri-urban area of Toluca city in Mexico, a socio-ecological systems framework was applied to study the nutrient pollution problem and recommend nutrient control measures.

Self-averaging in many-body quantum systems out of equilibrium: Time dependence of distributions.

In a disordered system, a quantity is self-averaging when the ratio between its variance for disorder realizations and the square of its mean decreases as the system size increases. Here, we consider a chaotic disordered many-body quantum system and search for a relationship between self-averaging behavior and the properties of the distributions over disorder realizations of various quantities and at different timescales. An exponential distribution, as found for the survival probability at long times, explains its lack of self-averaging, since the mean and the dispersion are equal.

Lloyd-model generalization: Conductance fluctuations in one-dimensional disordered systems.

We perform a detailed numerical study of the conductance G through one-dimensional (1D) tight-binding wires with on-site disorder. The random configurations of the on-site energies ε of the tight-binding Hamiltonian are characterized by long-tailed distributions: For large ε, P(ε)∼1/ε^{1+α} with α∈(0,2). Our model serves as a generalization of the 1D Lloyd model, which corresponds to α=1.

Simple descriptors and simple rules of the International Ovarian Tumor Analysis (IOTA) Group: a prospective study of combined use for the description of adnexal masses.

Objective: External validation of the IOTA group's three-step diagnostic model (Strategy 1) and comparison with assessment by an expert sonographer (Strategy 2).

Study Design: Prospective study in patients with persistent adnexal masses, in which an inexperienced sonographer performed transvaginal ultrasound applying simple descriptors (SD) and rules (SR) for classifying as benign or malignant. Any non-classifiable mass was then submitted to an expert examiner for subjective assessment (SA).

Universality in the spectral and eigenfunction properties of random networks.

By the use of extensive numerical simulations, we show that the nearest-neighbor energy-level spacing distribution P(s) and the entropic eigenfunction localization length of the adjacency matrices of Erdős-Rényi (ER) fully random networks are universal for fixed average degree ξ≡αN (α and N being the average network connectivity and the network size, respectively). We also demonstrate that the Brody distribution characterizes well P(s) in the transition from α=0, when the vertices in the network are isolated, to α=1, when the network is fully connected. Moreover, we explore the validity of our findings when relaxing the randomness of our network model and show that, in contrast to standard ER networks, ER networks with diagonal disorder also show universality.

Scattering and transport properties of tight-binding random networks.

We study numerically scattering and transport statistical properties of tight-binding random networks characterized by the number of nodes N and the average connectivity α. We use a scattering approach to electronic transport and concentrate on the case of a small number of single-channel attached leads. We observe a smooth crossover from insulating to metallic behavior in the average scattering matrix elements <|S(mn)|(2)>, the conductance probability distribution w(T), the average conductance , the shot noise power P, and the elastic enhancement factor F by varying α from small (α→0) to large (α→1) values.

[Intrauterine misoprostol for the prevention of bleeding cesarean].

Objective: To evaluate efficacy of misoprostol by intrauterine route for the prevention of the obstetrical hemorrhage and to know its effects collaterals.

Patients And Methods: Clinical and randomized test with 200 patients to those who one took place to them Caesarean. The Group A was applied placebo and the group B misoprostol (group B; 800 microg) intrauterine, after the birth of its newborns.