2,714 research outputs found
Transferring cash benefits through the banking sector in Colombia
This paper reviews the experience in transacting payments through the commercial banking system, to beneficiaries in Colombia's"Familias en Accion"program. The story told will be useful to those trying to solve the operational problem of moving cash, cost-effectively to large numbers of beneficiaries in social assistance, or similar programs. It shows the options considered, their advantages, disadvantages, and costs. Though some of the details may be specific to the country, and program, the approach to the analysis is broadly applicable.Banks&Banking Reform,Municipal Financial Management,Financial Intermediation,Financial Crisis Management&Restructuring,Health Monitoring&Evaluation
Effet de la matrice de l'eau sur l'élimination des micropolluants organiques par ozonation. Partie 2. Simulation de l'élimination d'un micropolluant dans les réacteurs idéaux
L'Ă©quation cinĂ©tique qui permet de calculer l'oxydation d'un micropolluant dans les rĂ©acteurs d'ozonation s'Ă©crit:-(d[P]/dt)=(KD[O3]L+KID[OHâ])[P]Kd et Kid: constantes de vitesse de l'ozone et des radicaux hydroxyles sur le micropolluant P.Dans la premiĂšre partie, l'approche thĂ©orique de la concentration en radicaux hydroxyles a montrĂ© que [OH·] est proportionnel Ă la concentration en ozone ([OH·] = k'[03]). On a donc:(d[P]/dt)=KG[O3]L[P] with KG=KD+KIDK'Dans un rĂ©acteur parfaitement agitĂ©, les concentrations en ozone et en micropolluant sont constantes et l'Ă©limination s'Ă©crit: ([P]/[Po])=(1/1+KG[O3]L Ï) with Ï=(V/Q)Dans un rĂ©acteur piston, les concentrations varient tout au long de la colonne et il est habituel de modĂ©liser un tel rĂ©acteur comme un grand nombre de R.P.A. en sĂ©rie de volume DeltaV et de hauteur DeltaH (Dans notre approche DeltaH = 0,01 m).Dans les deux cas, la simulation de l'Ă©limination du micropolluant est basĂ©e sur la connaissance de la valeur de kG et de la concentration en ozone dans l'eau [03]L[03]L est obtenue de la rĂ©solution des bilans massiques dans un volume V ou ~V. ozone Ă l'entrĂ©e + ozone transfĂ©rĂ© = ozone Ă la sortie + ozone consommĂ©L'ozone transfĂ©rĂ© utilise pour son calcul des relations semi-empiriques donnant la constante de Henry et la valeur du kLa.L'ozone consommĂ© est dĂ©duit de la relation Ă©tablie dans la partie 1:(d[O3]L/dt)=w[O3]LLes rĂ©sultats de la simulation sont comparĂ©s aux rĂ©sultats expĂ©rimentaux obtenus avec un pesticide organo-phosphorĂ©, le parathion. Les paramĂštres variables sont le temps de contact (300 - 600 s), le pH (6,7 - 8,2) et le taux de traitement (1 Ă 5 g/m3).Une valeur de kG comprise entre 500 et 600 M-Âčs-Âč donne une bonne corrĂ©lation entre les valeurs expĂ©rimentales et calculĂ©es. Cependant, on peut noter quelques diffĂ©rences, en particulier dans la partie basse de la colonne, ce qui montre la nĂ©cessitĂ© de prendre en compte pour des calculs plus prĂ©cis l'hydrodynamique du rĂ©acteur. L'emploi du programme de simulation permet de tracer deux abaques qui montrent l'influence pour n'importe quel micropolluant des facteurs kGteta et w.Micropollutant (P) oxidation in an ideal ozonation reactor uses the kinetic Ă©quation:(d[P]/dt)=(KD[O3]L+KID[OHâ])[P]kD and kID : kinetic rate constant of ozone and hydroxy radicals on the micro -pollutant P.In part 1, the theoritical Ă©quation shows that [OH°] is proportional to the ozone concentration ([OH°] = k'[O3]) and thus the following equation is obtained :(d[P]/dt)=KG[O3]L[P] with KG=KD+KIDK'In a completely stirred tank reactor, ozone concentration in liquid phase is constant and pesticide elimination is given by the equation :([P]/[Po])=(1/1+KG[O3]L Ï) with Ï=(V/Q)In a plug flow reactor, ozone concentration in liquid phase varies along the column. To modelize them, we use the model of completely stirred tank reactors in series where the unit volume is âV. In our calculations, this volume is obtained by S (reactor cross section area) and âh equal to 0,01 m. In this volume âV, ozone and micropoliutant concentrations are considerad as a constant.Simulation calculations are based on the knowledge of global kinetic constant kG and ozone concentration.The value of the ozone concentration is obtain from mass balances on the oxklant (on a âV or V volume reactor) :ozone inlet + transferred ozone = consumed ozone + ozone outletThe quantifies of transferred ozone are calculated from the Henry law and a semi empirical kLa equation.The quantity of consumed ozone is calculated from the equation in part I(d[O3]L/dt)=w[O3]LExperimental results are obtained with parathion, an organo-phosphorus pesticide on a bubble column pilot plant:Parameters are contact time (300-600 s), pH (6,7-8-2) and ozone treatment rate (1 to 5 g/m3).A kG value of 500 or 600 M-l s-l shows a good correlation between predicted and simulated pesticide concentrations.However, there are noticable differences, especially at the bottom of the column. This shows the necessity to take into account the hydrodynamic properties of the reactor during next works. The use of the simulation program lets to calculate the elimination of pesticide versus the two main parameters : the factor kGteta and the value of w
Morphometric and Histopathologic Changes in Skeletal Muscle Induced for Injectable PLGA Microparticles
Galdames, IS (Galdames, Ivan Suazo).Univ Talca, Talca, ChileThe administration of microencapsulated drug in a matrix acid poly(lactic-co-glycolic acid) (PLGA) by intramuscular (IM) in humans has been approved by the FDA for various applications though it is not clear what effect they have on the morphological parameters of muscle tissue. The aim of this study was to analyze the morphological changes in the skeletal muscle tissue with their use. We used 12 adult female Sprague Dawley rats (Rattus novergicus) that were injected into their right gastrocnemius muscle belly with: sterile vehicle solution (01, n = 4), 0.5 mg PLGA microparticle (02, n = 4) and 0.75 mg PLGA microparticle (03, n = 4), both dissolved in a sterile vehicle solution. At 14 days post injection the number and diameter of muscle fibers, the level of inflammation and histology appearance in terms of organization of muscle fibers, cellular distribution, tissue morphology and the presence of polymer waste were determined and the results between the groups compared. The administration of the compound in a single dose did not alter the morphometric parameters (number and diameter of muscle fibers) despite generating a mild inflammation in the tissue associated with the presence of polymeric residues, suggesting that the PLGA microparticles were well tolerated by the muscle tissue at concentrations tested (0.5 and 0.75 mg).
n Number: WOS:00029366100001
Intracellular trafficking and cellular uptake mechanism of PHBV nanoparticles for targeted delivery in epithelial cell lines
IndexaciĂłn: Web of Science; Scopus; Scielo.Background: Nanotechnology is a science that involves imaging, measurement, modeling and a manipulation of matter at the nanometric scale. One application of this technology is drug delivery systems based on nanoparticles obtained from natural or synthetic sources. An example of these systems is synthetized from poly(3-hydroxybutyrate-co-3-hydroxyvalerate), which is a biodegradable, biocompatible and a low production cost polymer. The aim of this work was to investigate the uptake mechanism of PHBV nanoparticles in two different epithelial cell lines (HeLa and SKOV-3).
Results: As a first step, we characterized size, shape and surface charge of nanoparticles using dynamic light scattering and transmission electron microscopy. Intracellular incorporation was evaluated through flow cytometry and fluorescence microscopy using intracellular markers. We concluded that cellular uptake mechanism is carried out in a time, concentration and energy dependent way. Our results showed that nanoparticle uptake displays a cell-specific pattern, since we have observed different colocalization in two different cell lines. In HeLa (Cervical cancer cells) this process may occur via classical endocytosis pathway and some internalization via caveolin-dependent was also observed, whereas in SKOV-3 (Ovarian cancer cells) these patterns were not observed. Rearrangement of actin filaments showed differential nanoparticle internalization patterns for HeLa and SKOV-3. Additionally, final fate of nanoparticles was also determined, showing that in both cell lines, nanoparticles ended up in lysosomes but at different times, where they are finally degraded, thereby releasing their contents.
Conclusions: Our results, provide novel insight about PHBV nanoparticles internalization suggesting that for develop a proper drug delivery system is critical understand the uptake mechanism.https://jnanobiotechnology.biomedcentral.com/articles/10.1186/s12951-016-0241-
Chilean health professionalsâ attitudes towards deafness: A cross-sectional study
IndexaciĂłn: Scopus.Objective: To assess the attitudes of health professionals towards Deafness and its association with sociodemographic and Deaf contact experience. Material and Methods: A cross-sectional study was carried out in Concepcion, Chile. The sample size was estimated in 171 health professionals. The following variables were considered: socio demographics, Deaf contact experience, and attitudes to deafness scale (ADS scale). To evaluate the association between the variables, t-test and Spearman correlation test were used (p<0.05). Results: People who had taken a LSCh course had significant more positive attitudes towards item 1 âDeaf people should learn to lipreadâ, with a 2 points difference and in persons who do not know a Deaf person, with 1-point difference. Also, persons who have received some kind of formation in Deafness have a better attitude in item 3 âI would like to have more Deaf friendsâ with 1-point difference. An inverse correlation was observed within age (rho =-0.237; p=0.0014), years of academic service (rho =-0.323; p<0.0001) or PHC service (rho =-0.1085; p=0,364). Conclusion: The attitude of health professionals towards Deafness was neutral. This attitude is not modulated by sex, type of profession, type of relationship with Deaf people, type of training in hearing disability, Chilean Sign Language Courses or degree of frequency of healthcare delivery to Deaf patients. However, it is modulated by age and years of service.https://www.scielo.br/j/pboci/a/XrS5NBvKGxkvpGYp4G3mFvs/?lang=e
Association between parental perceptions of residential neighbourhood environments and childhood obesity in Porto, Portugal
Portugal has one of the highest rates of childhood obesity in Europe. Few studies have explored the relationship between parentsâ perceptions of their residential neighbourhood (safety concerns and amenities of the built environment) and their childrenâs weight status. This study aims to examine the associations between parentsâ perceptions of their residential neighbourhood and overweight/obesity among their children. Methods: Anthropometric measures of height and weight were taken for 2690 children in preschools and elementary
schools in Porto. Body mass index (kg/m2 ) was calculated, and the International Obesity Taskforce (IOTF) cut-offs were used. Parents completed the âEnvironmental Moduleâ standard questionnaire of the International Physical Activity Prevalence Study. Chi-square tests and the logistic regression model adjusted for age, gender, maternal education and school cluster were used to examine the associations between parentsâ perceptions of their residential neighbourhood and overweight/obesity among their children. Results: In this sample, 31.8% of the children were overweight (including obese). Significant associations were found between child obesity and the following residential environmental characteristics: the odds of children being obese were lower if their parents believed that it was safe (low/no crime rate) to walk/cycle at night (OR = 0.65, 95% CI = 0.54â0.79) and during the day (OR = 0.70, 95% CI = 0.55â0.86) and that it was easy and pleasant (pedestrian safety) to walk in their neighbourhoods (OR = 0.73, 95% CI = 0.58â0.90) and when local sidewalks were well maintained and unobstructed (OR = 1.18, 95% CI = 1.01â1.40). Conclusion: Parental perceptions of neighbourhood safety and the quality of local sidewalks are significantly associated with obesity values
Quantum corrections to gravity and their implications for cosmology and astrophysics
The quantum contributions to the gravitational action are relatively easy to
calculate in the higher derivative sector of the theory. However, the
applications to the post-inflationary cosmology and astrophysics require the
corrections to the Einstein-Hilbert action and to the cosmological constant,
and those we can not derive yet in a consistent and safe way. At the same time,
if we assume that these quantum terms are covariant and that they have relevant
magnitude, their functional form can be defined up to a single free parameter,
which can be defined on the phenomenological basis. It turns out that the
quantum correction may lead, in principle, to surprisingly strong and
interesting effects in astrophysics and cosmology.Comment: 15 pages, LaTeX, WS style, contribution to the Proceedings of the
QFEXT-2011 conference in the Centro de Ciencias de Benasque Pedro Pasqual,
Spai
Perturbations in the relaxation mechanism for a large cosmological constant
Recently, a mechanism for relaxing a large cosmological constant (CC) has
been proposed [arxiv:0902.2215], which permits solutions with low Hubble rates
at late times without fine-tuning. The setup is implemented in the LXCDM
framework, and we found a reasonable cosmological background evolution similar
to the LCDM model with a fine-tuned CC. In this work we analyse analytically
the perturbations in this relaxation model, and we show that their evolution is
also similar to the LCDM model, especially in the matter era. Some tracking
properties of the vacuum energy are discussed, too.Comment: 18 pages, LaTeX; discussion improved, accepted by CQ
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