This work presents a mathematical model implementation for studying the diffusion process of ferric ions in post-irradiated Fricke gel dosimeters. Fricke gel samples were manufactured in layers for ...their analysis by optical transmission imaging and benzoic acid was incorporated to improve their radiosensitivity. The developed method consists on designing the dosimeters with a suitable composition for their optical analysis which allows accurate measurements in a wide dose range with noticeable linear responses with an average linear correlation coefficient of r2=0.993. The developed algorithm calculates the diffusion coefficient by means of an inverse problem formulation. Moreover, the proposed method is capable of modeling time-dependent physical properties and evolution over time of the irradiated dosimeters accurately and comparable with experimentally measured data. The obtained results evince the complexity of the diffusion phenomena in this type of materials and the capacity of the proposed method to provide a reliable quantification of the diffusion coefficient as a scalar approximation of the diffusion tensor. The obtained diffusion coefficient varies from 1.21 to 1.61 mm2/h with uncertainties lower than 2%. The model is also transferable to other diffusion driven systems and the numerical solving method can also be adapted to solve diffusion calculation based on other theoretical approaches.
•Post irradiation stability in Fricke gel dosimeters with benzoic acid was studied.•Inverse problem was used to characterize ferric ion diffusion in 2D.•Optical transmission images were suitable for diffusion coefficient calculation.
Background: Based on the pathophysiology of acute kidney injury (AKI), it is plausible that certain early interventions by the nephrologist could influence its trajectory. In this study, we ...investigated the impact of 5 early nephrology interventions on starting kidney replacement therapy (KRT), AKI progression, and death. Methods: In a prospective cohort at the Hospital Civil of Guadalajara, we followed up for 10 days AKI patients in whom a nephrology consultation was requested. We analyzed 5 early interventions of the nephrology team (fluid adjustment, nephrotoxic withdrawal, antibiotic dose adjustment, nutritional adjustment, and removal of hyperchloremic solutions) after the propensity score and multivariate analysis for the risk of starting KRT (primary objective), AKI progression to stage 3, and death (secondary objectives). Results: From 2017 to 2020, we analyzed 288 AKI patients. The mean age was 55.3 years, 60.7% were male, AKI KDIGO stage 3 was present in 50.5% of them, sepsis was the main etiology 50.3%, and 72 (25%) patients started KRT. The overall survival was 84.4%. Fluid adjustment was the only intervention associated with a decreased risk for starting KRT (odds ratio OR: 0.58, 95% confidence interval CI: 0.48–0.70, and p ≤ 0.001) and AKI progression to stage 3 (OR: 0.59, 95% CI: 0.49–0.71, and p ≤ 0.001). Receiving vasopressors and KRT were associated with mortality. None of the interventions studied was associated with reducing the risk of death. Conclusions: In this prospective cohort study of AKI patients, we found for the first time that early nephrologist intervention and fluid prescription adjustment were associated with lower risk of starting KRT and progression to AKI stage 3.
Ante los reiterados fracasos en la adopción de una reforma política que modifique el mecanismo de presentación de candidatos partidistas a las elecciones a corporaciones públicas en Colombia, el ...presente artículo examina si existe congruencia entre estas propuestas de reforma y la práctica política de partidos y movimientos políticos en la inscripción de sus candidatos. La información recopilada demuestra la existencia de dos planos que parecen no converger. De un lado, una serie de aspiraciones expresadas por sectores tanto gubernamentales y parlamentarios como de la sociedad civil que propugnan por la adopción de las listas cerradas y bloqueadas y, de otro, el recurso del voto preferente por parte de los actores políticos como mecanismo privilegiado para obtener curules. Esto último se comprueba al analizar, mediante técnicas de estadística descriptiva, variables relacionadas con la competencia política nacional y subnacional en elecciones a diferentes circunscripciones. Con el ejercicio académico se valida un postulado teórico sobre las reformas electorales: la resistencia por parte de los legisladores encargados de aprobarlas a modificar reglas de juego y a sancionar normas que eventualmente afecten sus carreras políticas.
Carotid artery stenosis (CAS) is a common vascular disease with long-term consequences for the brain. Although CAS is strongly associated with impaired cerebral hemodynamics and neurodegeneration, ...the mechanisms underlying hemodynamic impairment in the microvasculature remain unknown. In this work, we employed functional near-infrared spectroscopy (fNIRS) to introduce a methodological approach for quantifying the temporal delay of the evoked hemodynamic response. The method was validated during a vasodilatory task (breath-holding) in 50 CAS patients and 20 controls. Our results suggest that the hemodynamic response to breath-holding can be delayed by up to 6 s in the most severe patients, a significant increase from the median 4 s measured for the control group (p = 0.01). In addition, the fraction of brain regions that responded to the task decreased as the CAS severity increased, from a median of 90% in controls to 73% in the most severe CAS group (p = 0.04). The presence of collateral circulation increases the response to breath-holding and decreases the average time delays across the brain, although the number of communicating arteries alone cannot predict these fNIRS-based hemodynamic variables (p > 0.09). Overall, this work proposes a method to quantitatively assess impaired cerebral hemodynamics in CAS patients.
The main treatment strategy in type 1 cardiorenal syndrome (CRS1) is vascular decongestion. It is probable that sequential blockage of the renal tubule with combined diuretics (CD) will obtain ...similar benefits compared with stepped-dose furosemide (SF).
In a pilot double-blind randomized controlled trial of CRS1 patients were allocated in a 1:1 fashion to SF or CD. The SF group received a continuous infusion of furosemide 100 mg during the first day, with daily incremental doses to 200 mg, 300 mg and 400 mg. The CD group received a combination of diuretics, including 4 consecutive days of oral chlorthalidone 50 mg, spironolactone 50 mg and infusion of furosemide 100 mg. The objectives were to assess renal function recovery and variables associated with vascular decongestion.
From July 2017 to February 2020, 80 patients were randomized, 40 to the SF and 40 to the CD group. Groups were similar at baseline and had several very high-risk features. Their mean age was 59 ± 14.5 years, there were 37 men (46.2%). The primary endpoint occurred in 20% of the SF group and 15.2% of the DC group (p = 0.49). All secondary and exploratory endpoints were similar between groups. Adverse events occurred frequently (85%) with no differences between groups (p = 0.53).
In patients with CRS1 and a high risk of resistance to diuretics, the use of CD compared to SF offers the same results in renal recovery, diuresis, vascular decongestion and adverse events, and it can be considered an alternative treatment. ClinicalTrials.gov with number NCT04393493 on 19/05/2020 retrospectively registered.
Helicobacter pylori
is a microorganism that infects 60% of the population and is considered the main cause of atrophic gastritis, gastric and duodenal ulcers, and gastric cancer. Different emerging ...pathogens have been found in drinking water and their presence is considered to be an important public health problem. For this reason, it is necessary to carry out the validation of reliable technologies for this type of pathogens and evaluate their performance. This paper reports, for the first time,
H. pylori
reduction in a drinking water pilot plant of two slow sand filters (SSF). Inlet water was taken from a gravel filtration system of a rural water supply in Colombia and then inoculated with viable cells of
H. pylori
. By determining the Genomic Units (GU) through quantitative Polymerase Chain Reaction (qPCR), the concentration of GU/sample was measured. In the inlet water amplification for SSF1 and SSF2 were 5.13 × 10
2
± 4.48 × 10
2
and 6.59 × 10
2
± 7.32 × 10
2
, respectively, while for the treated water they were 7.0 ± 5.6 and 2.05 × 10
1
± 2.9 × 10
1
GU/sample for SSF1 and SSF2, respectively. The SSF pilot plant reached up to 3 log reduction units of
H. pylori
; therefore, since there is not an
H. pylori
contamination indicator and its periodic monitoring is financially complicated, the SSF could guarantee the drinking water quality necessity that exists in rural areas and small municipalities in developing countries, where infection rates and prevalence of this pathogen are high.
El presente artículo tiene como objetivo estudiar la manifestación de las poliarquías al interior del Estado colombiano desde la perspectiva de la teoría del estado posmoderna y su relación con la ...forma cómo puede aplicarse en la regulación de la protesta social.
Background. Genetic variability of Helicobacter pylori is associated with various gastrointestinal diseases; however, little is known about interaction with sociodemographic in the development of ...premalignant lesions in Colombian patients. Methods. An analytical study was conducted including cases (patients with gastric atrophy, intestinal metaplasia, and gastric dysplasia) and controls (patients with nonatrophic gastritis). Sociodemographic information was obtained using a questionnaire. Histopathological diagnosis was performed according to the Sydney System. The cagA and vacA genotypes were established using polymerase chain reaction in paraffin blocks. The effect of each variable on the study outcome (premalignant lesion) is presented as odds ratio (OR) and 95% CI. A p value of <0.05 was considered as statistically significant. Results. The vacA/s1m1 genotype increases the risk of developing premalignant lesions of the stomach (OR: 3.05, 95% IC: 1.57–5.91, p=0.001). Age and educational level showed a positive interaction with the s1m1 genotype (adjusted OR: 3.68, 95% CI: 1.73–7.82, p=0.001). The cagA genotype was not correlated to the development of premalignant lesions of the stomach (OR: 1.32, 95% CI: 0.90–1.94, p=0.151). Conclusions. The vacA genotype, age, and educational level are indicators of the risk of developing premalignant lesions of the stomach in the study population. Significance Statement. Genetic variability of H. pylori and sociodemographic information could be used to predict the risk of premalignant lesions in stomach in Colombian population.
The main purpose of this section is to present an academic proposal that functions as a "model of integral balance" for the judicial-constitutional decision based on an inclusive interdisciplinary ...discourse (law and economics) using the techniques of proportionality and weighting as methodological tools to achieve the intended balance. As explained in the second part of this work, there are several dogmatic and methodological deficiencies in the application of the aforementioned techniques (which have been used under a model that we call traditional or classic), but that could be overcome and / or mitigated from the proposal that will be developed in this section, always in search of efficient decisions in the assignment, but fair and/or equitable in distribution; that is, balanced decisions. To achieve the purpose cited, the structure of this section is limited to the following topics: i) introductory approach, ii) the technique of proportionality for integral equilibrium, iii) the weighting technique for integral equilibrium, and, iv) applications of the techniques under study to specific cases.
Esta investigación presenta a las marcas: Herbalife y la Iglesia de la Cienciología, quienes por medio de la construcción y difusión de su comunicación tienen una cercanía estructural con el término ...religión, lo que facilitó su ingreso al mercado bogotano, ciudad en la cual se realizó el estudio de estas marcas. Por medio de la inmersión etnográfica se pudo observar y argumentar que la marca Iglesia de la Cienciología es una religión, como se autodenomina, y por otra parte, se concluye que la marca Herbalife, por su estructura corporativa, también responde al término de una religión. Se encontró cómo el discurso publicitario propagandístico asociado a varios elementos de la anatomía de marca, permiten consolidar una fuerte estructura de marca y gracias a esta se puede construir una relación estrecha y fidelizada por parte de sus usuarios. En está investigación de corte cualitativo, se empleó la etnografía como herramienta principal, se realizó un proceso de inmersión, entrevistas semiestructuradas y diarios de campo. Para el análisis de la información se usó la disciplina del Branding, para construir un análisis comparativo; partiendo de veintisiete elementos que conforman la anatomía de marca, se escogieron tres de ellos para el desarrollo del análisis, la personalidad, la publicidad y la atención al cliente. Finalmente, se presentan unas conclusiones acerca de la cercanía entre la estructural comercial de Herbalife y la estructura religiosa de la Iglesia de la Cienciología, como marcas de culto, donde la comunicación y los canales de emisión del discurso juegan un papel primordial para su desarrollo y fortalecimiento.
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