Detection of enteric parasite DNA in household and bed dust samples: potential for infection transmission.

BACKGROUND: Enteric parasites are transmitted in households but few studies have sampled inside households for parasites and none have used sensitive molecular methods. METHODS: We collected bed and living room dust samples from households of children participating in a clinical trial of anthelmintic treatment in rural coastal Ecuador. Dust was examined for presence of DNA specific for 11 enteric parasites (Ascaris lumbricoides, Trichuris trichiura, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Toxocara canis and T. cati, Giardia lamblia, Blastocystis hominis, Cryptosporidium spp., and Entamoeba histolytica) by quantitative PCR (qPCR). RESULTS: Of the 38 households sampled, 37 had positive dust for at least one parasite and up to 8 parasites were detected in single samples. Positivity was greatest for B. hominis (79% of household samples) indicating a high level of environmental fecal contamination. Dust positivity rates for individual pathogens were: S. stercoralis (52%), A. lumbricoides (39%), G. lamblia (39%), Toxocara spp. (42%), hookworm (18%) and T. trichiura (8%). DNA for Cryptosporidium spp. and E. histolytica was not detected. Bed dust was more frequently positive than floor samples for all parasites detected. Positivity for A. lumbricoides DNA in bed (adjusted OR: 10.0, 95% CI: 2.0-50.1) but not floor dust (adjusted OR: 3.6, 95% CI: 0.3-37.9) was significantly associated with active infections in children. CONCLUSIONS: To our knowledge, this is the first use of qPCR on environmental samples to detect a wide range of enteric pathogen DNA. Our results indicate widespread contamination of households with parasite DNA and raise the possibility that beds, under conditions of overcrowding in a humid tropical setting, may be a source of transmission

Volumetric and anatomical MRI for hypoxic-ischemic encephalopathy: relationship to hypothermia therapy and neurosensory impairments.

OBJECTIVE: To relate volumetric magnetic resonance imaging (MRI) findings to hypothermia therapy and neurosensory impairments. STUDY DESIGN: Newborns \u3e or =36 weeks\u27 gestation with hypoxic-ischemic encephalopathy who participated in the National Institute of Child Health and Human Development hypothermia randomized trial at our center were eligible. We determined the relationship between hypothermia treatment and usual care (control) to absolute and relative cerebral tissue volumes. Furthermore, we correlated brain volumes with death or neurosensory impairments at 18 to 22 months. RESULT: Both treatment groups were comparable before randomization. Total brain tissue volumes did not differ in relation to treatment assignment. However, relative volumes of subcortical white matter were significantly larger in hypothermia-treated than control infants. Furthermore, relative total brain volumes correlated significantly with death or neurosensory impairments. Relative volumes of the cortical gray and subcortical white matter also correlated significantly with Bayley Scales psychomotor development index. CONCLUSION: Selected volumetric MRI findings correlated with hypothermia therapy and neurosensory impairments. Larger studies using MRI brain volumes as a secondary outcome measure are needed

Heat transport in an open transverse-field Ising chain

The heat conduction in an open transverse-field Ising chain is studied by using quantization in the Fock space of operators in the weak coupling regimes, i.e. the coupling is much smaller than the transverse field. The non-equilibrium steady state is obtained for large size systems coupled to Markovian baths at its ends. The ballistic transport is observed in the uniform chain and normal diffusion in the random-exchange chain. {In addition, the ballistic-diffusive transition is found at the intermediate disorder regime.} The thermal conductivity $\kappa$ is also calculated in the low and high temperature regimes. It is shown that $\kappa$ decays as $\kappa\sim T^{-2}$ at high temperatures.Comment: 6 pages, 7 figure

Third quantization: a general method to solve master equations for quadratic open Fermi systems

The Lindblad master equation for an arbitrary quadratic system of n fermions is solved explicitly in terms of diagonalization of a 4n x 4n matrix, provided that all Lindblad bath operators are linear in the fermionic variables. The method is applied to the explicit construction of non-equilibrium steady states and the calculation of asymptotic relaxation rates in the far from equilibrium problem of heat and spin transport in a nearest neighbor Heisenberg XY spin 1/2 chain in a transverse magnetic field.Comment: 24 pages, with 8 eps figures - few minor corrections to the published version, e.g. anti-symmetrizing the matrix given by eq. (27

CIP-OFIAGRO: estudio de perdidas pos-cosecha en la cadena de la papa en Ecuador.

Peer Revie

Using meteorological measurements from different sources to evaluate the human comfort in urban area

Climate change affects the thermal and human comfort in urban areas. This is more evident in equatorial towns that have experienced, in the last decades, of an increase of air temperature which, acting together with the increasing of the rain rate, generates a strong deterioration of the human comfort. The characterization of the urban heat island is one of the most important points in the agenda of the Research Centers, as well as of the Weather Services of the Nations located in the equatorial area. The Escuela Superior Politecnica del Litoral (Ecuador), jointly with the Instituto Nacional de Meteorologia e Hidrologia (INAMHI - Ecuador) and with the Politecnico di Torino and the Università di Torino (Italy), started a project devoted to the analysis of the thermal comfort in the Guayaquil urban area. The research is funded by the Secretaria de Educacion Superior, Ciencia, Tecnologia e Innovacion (SENESCYT – Ecuador) in the context of the PROMETEO project. The preliminary results of this research show us how, to better describe the thermal comfort in the urban area, it is important to have available the meteorological parameters measured by a meso-network of Automatic Weather Stations. The elaboration of these measures with the Universal Thermal Climate Indices, like the PMV and the PET, provide a detailed analysis of the thermal comfort and of the related human comfort in the urban area. The results of this analysis are to be evaluated jointly with the aerological measurements and with the remote sensing images to characterize correctly the urban heat island

Scalable quantum dot based optical interconnects

Scalable quantum dot based optical switches offer energy-efficient low-latency data routing. Low power penalty routing over multiple stages are feasible with with the prospect of larger scale photonic integration