Instituto Venezolano Of Investigaciones Cientificas Ivic
Instituto Venezolano Of Investigaciones Cientificas Ivic
Acevedo-Malave A.,Instituto Venezolano Of Investigaciones Cientificas Ivic
Journal of Computational Methods in Sciences and Engineering | Year: 2017
A computational fluid dynamics approach is employed in this paper for the modeling of the coalescence phenomenon between many drops. Therefore, drops of water immersed in a hydrocarbon phase (n-heptane) were defined inside the flow solver. This numerical approach is based on the finite volume method and some value for the initial velocity of coalescence was chosen. Due to this value of the velocity of collision some scenarios arise where can be seen the formation of vortexes at many zones of the system. The streamlines were computed inside the drops and the dynamics of the coalescence can be understood in terms of this. In the model reported here the surface tension and the gravity forces are included. © 2017 - IOS Press and the authors.
Montilva M.,University Centroccidental Lisandro Alvarado |
Berne Y.,University Centroccidental Lisandro Alvarado |
Papale J.,University Centroccidental Lisandro Alvarado |
Garcia-Casal M.N.,Instituto Venezolano Of Investigaciones Cientificas Ivic |
And 2 more authors.
Anales Venezolanos de Nutricion | Year: 2010
The objective was to study the nutritional status and food habits of women of childbearing age (12 to 45 years) from Municipio Jimenez, Lara State, Venezuela. The sample consisted in 243 women, randomly selected from rural and urban conglomerates of the Municipio. Each woman was requested to fill a questionnaire, with personal and socioeconomic information, between September 2007 and April 2008. Weight, height, mid arm circumferences and skinfolds were obtained. The body mass index and composition indicators were calculated. The nutritional status of the group was classified according to national and international standards. Dietetic evaluation consisted in one food frequency and two food recall questionnaires. Overweight was present in 46.6% of women, being higher in adult women, low weight affected 8.3% being significantly more frequent in adolescents (p=0,000). There were important deficiencies in consumption adequacy of calcium (34.7%), zinc (20.9%), copper (13.3%), folates (41.5%), vitamins B6 (19.8%), C (62.6%), proteins (72.0%) and calories (58.1%). Cereals and edible fats were consumed daily by more than 90% of the sample. Intake of dairy products (61.7%), meats and eggs (76.5%), grains (17.0%), fruits (40.0%), and vegetables (14.0%), was less frequent. In conclusion, the population studied showed the simultaneous co-existence of excess and deficit of weight as well as inadequate food habits, that justify the implementation of intervention programs to diminish mortality and the risk of non-transmissible chronic diseases.
Tosta M.,Instituto Venezolano Of Investigaciones Cientificas Ivic |
Oliveros J.C.,Central University of Venezuela |
Mora J.R.,Instituto Venezolano Of Investigaciones Cientificas Ivic |
Cordova T.,Central University of Venezuela |
Chuchani G.,Instituto Venezolano Of Investigaciones Cientificas Ivic
Journal of Physical Chemistry A | Year: 2010
The gas-phase elimination kinetics of N-benzylglycine ethyl ester was examined in a static system, seasoned with allyl bromide, and in the presence of the free chain radical suppressor toluene. The working temperature and pressure range were 386.4-426.7 °C and 16.7-40.0 torr, respectively. The reaction showed to be homogeneous, unimolecular, and obeys a first-order rate law. The elimination products are benzylglycine and ethylene. However, the intermediate benzylglycine is unstable under the reaction conditions decomposing into benzyl methylamine and CO2 gas. The variation of the rate coefficients with temperature is expressed by the following Arrhenius equation: log k1 (s-1) = (11.83 ± 0.52) - (190.3 ± 6.9) kJ mol -1 (2.303RT)-1. The theoretical calculation of the kinetic parameters and mechanism of elimination of this ester were performed at B3LYP/6-31G*, B3LYP/6-31+G**, MPW1PW91/6-31G*, and MPW1PW91/6-31+G** levels of theory. The calculation results suggest a molecular mechanism of a concerted nonsynchronous six-membered cyclic transition state process. The analysis of bond order and natural bond orbital charges implies that the bond polarization of C(=O)O-C, in the sense of C(=O)Oδ-⋯Cδ+, is rate determining. The experimental and theoretical parameters have been found to be in reasonable agreement. © 2010 American Chemical Society.
PubMed | Venezuelan Institute for Scientific Research and Instituto Venezolano Of Investigaciones Cientificas Ivic
Type: Journal Article | Journal: The Lancet. Infectious diseases | Year: 2015
Whole-genome sequencing (WGS) is now common as a result of new technologies that can rapidly sequence a complete bacterial genome for US$500 or less. Many studies have addressed questions about tuberculosis with WGS, and knowing the sequence of the entire genome, rather than only a few fragments, has greatly increased the precision of molecular epidemiology and contact tracing. Additionally, topics such as the mutation rate, drug resistance, the target of new drugs, and the phylogeny and evolution of the Mycobacterium tuberculosis complex bacteria have been elucidated by WGS. Nonetheless, WGS has not explained differences in transmissibility between strains, or why some strains are more virulent than others or more prone to development of multidrug resistance. With advances in technology, WGS of clinical specimens could become routine in high-income countries; however, its relevance will probably depend on easy to use software to efficiently process the sequences produced and accessible genomic databases that can be mined in future studies.
PubMed | Instituto Venezolano Of Investigaciones Cientificas Ivic
Type: Journal Article | Journal: Investigacion clinica | Year: 2014
This article reviews studies of distant mental influence on living organisms, including mental suggestions of sleeping and awakening, mental influence at long distances, mental interactions with remote biological systems, mental effects on physiological activity and the sense of being stared at. Significant effects of distant mental influence have been shown in several randomized controlled trials in humans, animals, plants, bacteria and cells in the laboratory. Although distant mental influence on living organisms appears to contradict our ordinary sense of reality and the laws defined by conventional science, several hypotheses have been proposed to explain the observed effects; they include skeptical, signal transfer, field, multidimensional space/time and quantum mechanics hypotheses. In conclusion, as the progress of physics continues to expand our comprehension of reality, a rational explanation for distant mind-matter interaction will emerge and, as history has shown repeatedly, the supernatural events will evolve into paranormal and then, into normal ones, as the scientific frontiers expand.