1,694 research outputs found
Enabling Future Sustainability Transitions: An Urban Metabolism Approach to Los Angeles Pincetl et al. Enabling Future Sustainability Transitions
Summary: This synthesis article presents an overview of an urban metabolism (UM) approach using mixed methods and multiple sources of data for Los Angeles, California. We examine electric energy use in buildings and greenhouse gas emissions from electricity, and calculate embedded infrastructure life cycle effects, water use and solid waste streams in an attempt to better understand the urban flows and sinks in the Los Angeles region (city and county). This quantification is being conducted to help policy-makers better target energy conservation and efficiency programs, pinpoint best locations for distributed solar generation, and support the development of policies for greater environmental sustainability. It provides a framework to which many more UM flows can be added to create greater understanding of the study area's resource dependencies. Going forward, together with policy analysis, UM can help untangle the complex intertwined resource dependencies that cities must address as they attempt to increase their environmental sustainability
Manifestaciones cutáneas del dengue. Reporte de caso y revisión de la literatura
El dengue es un arbovirosis trasmitido por el mosquito Aedes
aegypti (MAe) infectado, que se presenta de forma epidémica
o endémica en áreas tropicales y subtropicales. Sus manifestaciones
cutáneas (MC) más frecuentemente reportadas
son las lesiones eritemato-papulo-purpúricas, las cuales
se presentan a partir del segundo a quinto día de la infección.
La Organización Mundial de la Salud (OMS) reconoce que
la incidencia del dengue ha incrementado extraordinariamente
en todo el mundo. En el año 2010, se reportaron de
50 a 100 millones de casos; de éstos, 1.6 correspondieron al
continente Americano. En México la frecuencia de dengue
ha incrementado.El dengue es una enfermedad transmitida por un vector denominado mosquito
Aedes aegypti (MAe), que generalmente está infectado por el virus del serotipo 2. Predomina en
regiones tropicales y subtropicales de todo el mundo. El cuadro clínico inicia de 3 a 7 días
después de la picadura y sus manifestaciones cutáneas (MC) representan una frecuencia que va
del 20% hasta el 65%, la cual varía de acuerdo a cada país.
En México los casos han incrementado. Sus lesiones más comunes son: la mácula (M), exantema
cutáneo morbiliforme (ECM), lesiones purpúricas (LP), petequias (P), entre otras. El objetivo de
este estudio es señalar el panorama que representan las MC del dengue. Se presenta el caso
clínico de una mujer joven, en quien se destacan estas manifestaciones, las cuales formaron
parte de la tríada del dengue, sin datos de alarma. Las MC del dengue son escasamente referidas
en su descripción, por lo que abordamos este tema con el fin de detallar las lesiones encontradas
y dar pie a la observación de más casos. No son patognomónicas y generalmente no reflejan
la gravedad de la infección.
El ECM y las M forman parte de las MC más comunes. Tienen un carácter generalmente benigno.
Los frentes de las tormentas actuales pueden impactar en el incremento de nuevos casos
Fluoride in ash leachates: environmental implications at Popocatépetl volcano, central Mexico
Ash emitted by volcanic eruptions, even of moderate magnitude, may affect the environment and the health of humans and animals through different mechanisms at distances significantly larger than those indicated in the volcanic hazard maps. One such mechanism is the high capacity of ash to transport toxic volatiles like fluoride, as soluble condensates on the particles' surface. The mobilization and hazards related to volcanic fluoride are discussed based on the data obtained during the recent activity of Popocatépetl volcano in Central Mexico
Vine Robots: Design, Teleoperation, and Deployment for Navigation and Exploration
A new class of continuum robots has recently been explored, characterized by
tip extension, significant length change, and directional control. Here, we
call this class of robots "vine robots," due to their similar behavior to
plants with the growth habit of trailing. Due to their growth-based movement,
vine robots are well suited for navigation and exploration in cluttered
environments, but until now, they have not been deployed outside the lab.
Portability of these robots and steerability at length scales relevant for
navigation are key to field applications. In addition, intuitive
human-in-the-loop teleoperation enables movement in unknown and dynamic
environments. We present a vine robot system that is teleoperated using a
custom designed flexible joystick and camera system, long enough for use in
navigation tasks, and portable for use in the field. We report on deployment of
this system in two scenarios: a soft robot navigation competition and
exploration of an archaeological site. The competition course required movement
over uneven terrain, past unstable obstacles, and through a small aperture. The
archaeological site required movement over rocks and through horizontal and
vertical turns. The robot tip successfully moved past the obstacles and through
the tunnels, demonstrating the capability of vine robots to achieve navigation
and exploration tasks in the field.Comment: IEEE Robotics and Automation Magazine, 2019. Video available at
https://youtu.be/9NtXUL69g_
Imprints of clustering in multiplicity fluctuations
In this paper, we investigate the multiplicity fluctuations of charged
particles observed in high-energy nuclear collisions and relate them to the
size of hadronizing systems which happen during such processes. We use the
average multiplicities and variances of
multiplicity distributions of charged particles produced in centrality selected
collisions of relativistic heavy-ion nuclei to evaluate the dynamic variable
and study its dependence on the size of colliding nuclei. We connect
the observed system-size dependence of multiplicity fluctuations with the
clustering phenomena and the finiteness of the hadronizing sources and the
thermal bath
Revised and extended analysis of five times ionized xenon, Xe Vi
A capillary discharge tube was used to record the Xe spectrum in the 400-5500 Å region. A set of 243 lines of the Xe VI spectrum was observed, and 146 of them were classified for the first time. For all known lines, we calculated the weighted oscillator strengths (gf) and weighted transition probabilities (gA) using the configuration interaction in a relativistic Hartree-Fock approach. The energy matrix was calculated using energy parameters adjusted to fit the experimental energy levels. Core polarization effects were taken into account in our calculations. Experimental energy values and calculated lifetimes are also presented for a set of 88 levels. From these levels, 32 were classified for the first time and 33 had their values revised. Our analysis of the 5s5p5d and 5s5p6s configurations was extended in order to clarify discrepancies among previous works216
Biological observations of the tope shark, Galeorhinus galeus , in the northern Patagonian gulfs of Argentina
During 1994–96, an experimental longline fishery for tope shark (Galeorhinus galeus) was carried out in the Nuevo Gulf of northern Patagonia and, in the summers of 2000–2001 and 2002, three boats conducted an exploratory commercial fishery for this species, accompanied by a scientific monitoring program. This paper summarizes the results of these fishing trials, and provides information on the biology of tope shark. Catches were highest from February to April, when tope shark represented 36% of the total fish caught, and elephant fish (Callorhynchus callorhynchus) and argentine hake (Merluccius hubbsi) accounted for 33% and 23%, respectively. Tope shark arriving in northern Patagonian waters during the summer are primarily mature males, immature and maturing females in their first and second non-gravid year. No gravid females were caught. These fish are part of the South-western Atlantic stock, which shows signs of over-exploitation, so we suggest that any longline fishery in Patagonia should remain on a small scale. We also recommend that an effective management plan is needed for the whole tope stock, establishing agreements on effort control and co-ordinated research between Brazil, Uruguay and Argentina.Fil: Elias, Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Rodriguez, A. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Hasan, E.. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Reyna, M. V.. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Amoroso, Ricardo Oscar. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentin
Electrochemical oxidation of oxalic acid in the presence of halides at boron doped diamond electrode
Aim of this work is to discuss the electrochemical oxidation of oxalic acid (OA), analyzing the influence of NaCl and NaBr. Experiments were carried out at boron-doped diamond (BDD) electrodes, in alkaline media. BDD electrodes have a poor superficial adsorptivity so their great stability toward oxidation allows the reaction to take place with reactants and intermediates in a non-adsorbed state. The process is significantly accelerated by the presence of a halogen salt in solution; interestingly, the mediated process does not depend on applied current density. Based on the results, bromide was selected as a suitable mediator during OA oxidation at BDD. Br- primarily acts in the volume of the solution, with the formation of strong oxidants; while Cl- action has shown lower improvements in the OA oxidation rate at BDD respect to the results reported using Pt electrode. Finally, the parameters of removal efficiency and energy consumption for the electrochemical incineration of OA were calculated. O objetivo deste trabalho é discutir a oxidação eletroquímica do ácido oxálico (AO), analisando a influência do NaCl e NaBr. Experimentos foram realizados em eletrodos de diamante dopados com boro (DDB), em meio alcalino. Eletrodos DDB têm uma baixa adsortividade superficial, portanto sua grande estabilidade frente à oxidação permite que a reação ocorra com reagentes e intermediários não adsorvidos. O processo é significativamente acelerado pela presença de sal de halogênio na solução; curiosamente, o processo mediado não depende da densidade de corrente aplicada. Com base nos resultados, o brometo foi selecionado como um mediador apropriado durante a oxidação de AO em DDB. Br- age primeiramente no volume da solução, com a formação de oxidantes fortes, enquanto a ação do Cl- mostrou melhoras mais baixas na oxidação do AO em BDD, com relação aos resultados relatados usando eletrodo de Pt. Finalmente, os parâmetros de eficiência de remoção e consumo de energia para a incineração eletroquímica de AO foram calculados
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