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Purpose: To investigate, in vitro, the dimensional accuracy of two impression techniques (squared impression copings and squared impression copings sandblasted and coated with impression adhesive) made of vinyl polysiloxane and polyether impression materials. Materials and Methods: A master cast (control group) with four parallel implant abutment analogs, a passive framework, and a custom aluminum tray was fabricated. Four groups (n = 5 each group) were tested: squared Impregum (SI), squared Express (SE), sandblasted adhesive squared Impregum (ASI), and sandblasted adhesive squared Express (ASE). The measurement method employed was just one titanium screw tightened to the framework. A stereomicroscope was used to evaluate the fit of the framework by measuring the size of the gap between the abutment and the framework. The results were analyzed statistically. Results: The mean values for the abutment/framework interface gaps were: master cast, 31.63 Mum (SD 2.16); SI, 38.03 Mum (SD 9.29); ASI, 46.80 Mum (SD 8.47); SE, 151.21 Mum (SD 22.79); and ASE, 136.59 Mum (SD 29.80). No significant difference was detected between the SI or ASI techniques and the master cast. No significant difference was detected between the SE and ASE techniques. Conclusion: Within the limitations of this study, it can be concluded that Impregum Soft medium consistency was the best impression material and the impression technique did not influence the accuracy of the stone casts. Int J Oral Maxillofac Implants 2010;25:771-776. [ABSTRACT FROM AUTHOR]

The removal kinetics of an aqueous mixture of thirteen antibiotics (i.e., ampicillin, cefuroxime, ciprofloxacin, flumequine, metronidazole, ofloxacin, oxytetracycline, sulfadimethoxine, sulfamethoxazole, sulfamethazine, tetracycline, trimethoprim and tylosin) by batch UV C and UV C /H 2 O 2 processes has been modeled in this work. First, molar absorption coefficients (ε), direct quantum yields (Φ) and the rate constants of the reaction of antibiotics with hydroxyl radical (k HO• ) (model inputs) were determined for each antibiotic and compared with literature data. The values of these parameters range from 0.3 to 21.8 mM -1  cm -1 for ε, < 0.01 to 67.8 mmol·E -1 for Φ and 3.8 × 10 9 to 1.7 × 10 10  M -1  s -1 for k HO• . Second, a regression model was developed to compute the rate constants of the reactions of the antibiotics with singlet oxygen (k 1 O₂ ) from experimental data obtained in batch UV C experiments treating a mixture of the antibiotics. k 1 O₂ values in the 1-50 × 10 6  M -1  s -1 range were obtained for the antibiotics studied. Finally, a semi-empirical kinetic model comprising a set of ordinary differential equations was solved to simulate the evolution of the residual concentration of antibiotics and hydrogen peroxide (model outputs) in a completely mixed batch photoreactor. Model predictions were reasonably consistent with the experimental data. The kinetic model developed might be combined with computational fluid dynamics to predict process performance and energy consumption in UV C and UV C /H 2 O 2 applications at full scale., (© 2024. The Author(s).)

Gas-phase and aqueous oxidations of formic and oxalic acids with ozone and OH radicals have been thoroughly examined by DFT methods. Such acids are not only important feedstocks for the iterative construction of other organic compounds but also final products generated by mineralization and advanced oxidation of higher organics. Our computational simulation unravels both common and distinctive reaction channels, albeit consistent with known H atom abstraction pathways and formation of hydropolyoxide derivatives. Notably, reactions with neutral ozone and OH radical proceed through low-energy concerted mechanisms involving asynchronous transition structures. For formic acid, carbonylic H-abstraction appears to be more favorable than the dissociative abstraction of the acid proton. Formation of long oxygen chains does not cause a significant energy penalty and highly oxygenated products are stable enough, even if subsequent decomposition releases environmentally benign side substances like O 2 and H 2 O.

Harmful alcohol use is a public health problem worldwide, contributing to an estimated 5.1% of the global burden of illness. Screening and addressing at-risk drinking in primary care settings is an empirically supported health care intervention strategy to help reduce the burden of alcohol-use problems. In preparation for introducing screening and treatment for at-risk drinking in primary care clinics in Colombia, we conducted interviews with clinicians, clinic administrators, patients, and participants in Alcoholics Anonymous. Interviews were conducted within the framework of the Detección y Atención Integral de Depresión y Abuso de Alcohol en Atención Primaria (DIADA, [Detection and Integrated Care for Depression and Alcohol Use in Primary Care] www.project-diada.org) research project, and its qualitative phase that consisted of the collection of data from 15 focus groups, 6 interviews and field observations in 5 regional settings. All participants provided informed consent to participate in this research. Findings revealed the association of harmful alcohol use with a culture of consumption, within which it is learned and socially accepted practice. Recognition of harmful alcohol consumption includes a social context that influences its screening, diagnosis and prevention. The discussion highlights how, despite the existence of institutional strategies in healthcare settings and the awareness of the importance of at-risk drinking among health personnel, the recognition of the harmful use of alcohol as a pathology should be embedded in an understanding of historical, social and cultural dimensions that may affect different identification and care scenarios., (Copyright © 2021 Asociación Colombiana de Psiquiatría. All rights reserved.)

Introduction: Objective: we conducted a systematic review of the main scientific evidence that associates food insecurity with a higher frequency of obesity and cardiometabolic risks in Mexican women. Design: a systematic review. Data sources: MEDLINE, Embase, CINAHL Plus, Web of Science, CAB Abstracts and PAIS Index. Selection criteria: articles that met the journal quality criteria and integrated food status with health insecurity, in which the situation of vulnerability in the current statistics for cardiometabolic diseases and risks that are associated with food insecurity was shown in women and their homes. Data analysis: relevance and quality of the results regarding food security, the presence of overweight and obesity, and socio-environmental indicators in women. Results: households headed by women who are at higher risk of having some degree of food insecurity or food assistance associated with the presence of obesity and overweight (RR = 1.28 to 2.97; 95 % CI: 1.08-1.44 to 1.52-6.14) as well as the development of cardiometabolic diseases such as diabetes mellitus (with a history of pregnancy as risk factor for developing diabetes and hypertension) presenting premature labor, shorter stature in the adult stage, a deficiency in micronutrients such as iron and antioxidant vitamins. Conclusion: the evidence found shows an association of food insecurity as found in women and their homes with a greater risk of being overweight and obese, as well as the development of a cardiometabolic disease (diabetes, hypertension), in addition to anemia and vitamin deficiency.

Oudemansiella species are worldwide distributed and they are characterized for having attractive appearance, a soft fleshy context and mild taste and odor, what makes them interesting for mushroom intensive production. However, studies on their cultivation are scarce and there is no information regarding productive and morphological parameters of fruiting bodies obtained in culture. Here, we propose a methodology to determine the best production technique for the cultivation of not only Oudemansiella species but also of other xylophagous species assaying five different mushroom cultivation systems. Also, the optimal temperature of vegetative growth, the optimal lignocellulosic substrates and the nutritional properties of two naturally occurring Oudemansiella species were determined. As a result, bags with holes-system proved to be the most appropriate technique for the production of fruiting bodies, 25 °C was determined as the optimal temperature for mycelial growth and wheat straw as the best substrate. The evaluated species showed a higher content of fats and fiber and a lower content of proteins and carbohydrates compared to other mushrooms. Furthermore, this is the first report of the cultivation of O. cubensis on agricultural wastes in the world.

New technologies to address the presence of pharmaceutical and personal care products (PPCPs) in wastewater are needed, especially in those cases in which water will be reused. In this work, the activation of peroxymonosulfate (PMS) with simulated solar radiation has been applied to the oxidation of a mixture of six PPCPs, i.e. caffeine, primidone, N,N-diethyl-3-methylbenzamide (DEET), methylparaben, clofibric acid and ibuprofen. The sole application of solar radiation, i.e. solar photolysis, only led to the oxidation of clofibric acid (complete degradation in 90 min). The combination of PMS and solar radiation resulted in the degradation of all target micropollutants. The complete degradation of this mixture at initial 100 ppb was achieved with 0.5 mM of initial PMS after 90 min. A kinetic study that acceptably simulates the experimental data under different conditions has been proposed. The effects of initial PPCP concentration (1 mg L -1 -100 μg L -1 ), PMS dose (0.1-5 mM), and pH (3-9) were tested and kinetically simulated. Finally, the PPCPs removal study was carried out in two real water matrices (river and a secondary effluent of an urban wastewater treatment plant). A higher dose of PMS, ten times higher, was required to achieve complete degradation of the micropollutants if compared to ultrapure water., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This work investigates the potential of the combination of peroxymonosulfate (PMS) and simulated solar radiation (λ > 300 nm) to remove bezafibrate from aqueous solution. Different solar light filters indicate a higher removal efficiency as the wavelength range used moves to the more energetic region of the solar spectrum. The system PMS/Daylight (300-800 nm) eliminates bezafibrate (1 mg L -1 ) in less than 30 min under the best conditions used in this study (C PMS  = 4·10 -4  M) with no pH control (acidic pH). The efficiency of the process significantly improves under alkaline conditions (pH = 10), likely due to a higher PMS photolysis rate. Experiments conducted at different initial concentration of PMS and bezafibrate suggest first order regarding PMS and different from 1 in the case of bezafibrate. Intermediates generated at the beginning of the process have been tentatively identified to propose a hypothetical reaction pathway and to estimate their toxicity., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Introduction: Background: hearing disorders in the premature newborns impact on their development and language and therefore, on their quality of life. Several risk factors have been associated to these conditions, but little is known about socioeconomic, nutrition factors and food security. Objective: to analyze the association between food security and prenatal risk factors in newborns with hearing disorders. Material and methods: study of 35 cases and 105 controls in premature newborns from 30 to 37 weeks of gestation (WG) in a public hospital. The working tool was a questionnaire to collect data about the maternal medical record and the anthropometry of the newborn, as well as the risk factors for the auditory function, sociodemographic aspects, and food security with its respective classification and food habits. Results: the principal perinatal risk factor associated to hearing impairment was the use of gentamycin (ototoxic drug) in 18.1% of the total (OR: 5.61 [1.29-24.50]). Severe food insecurity was associated with auditory disfunctions in 27.2% of cases and in 2.8% of controls (OR: 12.75 [2.89-56.16]). There were differences between the groups regarding the education level (cases: 50% of the mothers finished or interrupted primary education level vs controls with 19%; Ji2 = 0.008). The anthropomorphic variables showed differences in weight, length and cephalic perimeter for the newborns (p < 0.000). Conclusion: severe food insecurity, exposure to gentamycin and low education level of the mother had a significant association with auditory impairments in preterm children. For these newborns, variables like weight, length and cephalic perimeter at the moment of birth were lower than in controls. These initial findings point to the important role that environmental risks, like food insecurity, have in auditory impairments in addition to those previously described.

Clostridium difficile is a Gram-positive bacillus that has become one of the main hospital-acquired human gastrointestinal infections in recent years. Its incidence is on the rise, involving more virulent strains, affecting new and previously uncontemplated groups of patients, and producing changes in clinical presentation and treatment response that influence disease outcome. Early diagnosis and disease stratification based on the severity of C.difficile infection are essential for therapeutic management and the implementation of containment measures. However, the speed at which new strains with greater pathogenicity are developing is surpassing that of the development of new drugs, making it necessary to validate other therapeutic options. The present article is a review of the epidemiologic, pathophysiologic, diagnostic, and therapeutic aspects of C.difficile infection, from its first isolation to the present date, that aims to contribute to the preparation of general physicians and specialists, so that patients with this infection receive opportune and quality medical attention., (Copyright © 2017 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.)

The decomposition of aqueous ozone by UV-vis radiation has been investigated with focus on the impact of ozone photolysis on the degradation of water pollutants during solar ozonation processes. The apparent first-order rate constants of the decomposition of ozone (kobs) have been determined at various pHs in the 4-9 range using radiation of different wavelengths in the UV-vis range. It was found that UVA-visible radiation (λ>320nm) highly enhanced ozone decomposition, especially at pH 4, for which kobs was three-folded with respect to the process in the absence of radiation. Hydrogen peroxide was identified as a main intermediate of ozone photo-decomposition at pH 4. Experiments of degradation of oxalic acid by ozone showed that solar irradiation brings about an increase in the hydroxyl radical to ozone exposures ratio (Rct). Finally, photo-ozonation (λ>300nm) was shown advantageous over single ozonation in the mineralization of a selection of emerging contaminants (metoprolol, ibuprofen, N,N-diethyl-meta-toluamide and clofibric acid) in both ultrapure water and a synthetic secondary effluent. Thus, TOC removal in 2-h treatments increased from 10 to 25% in the absence of radiation to about 50% in the presence of radiation., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The article seeks to present the necessary context and a preliminary approach to understanding and addressing the birth control debate in Colombia in the 1960s and 1970s. It covers the main conflicting positions during that period and the discourses and logics permeating the arrival of North American family planning programs to Latin America as a form of political control of revolutionary movements.

Purpose: This in vitro study compared the dimensional accuracy of a stone index and of two impression techniques (squared impression copings and modified squared impression copings) for implant-supported prostheses., Materials and Methods: A master cast with four parallel implant-abutment analogs and a passive framework were fabricated. Vinyl polysiloxane impression material was used for all impressions with a metal stock tray. Three groups of impressions were tested (n = 5): index (I), squared (S), and modified squared (MS). The measurement method employed was just one titanium screw tightened to the framework. The measurements (60 gap values) were analyzed using software that received the images from a video camera coupled to a stereomicroscope at 3100 magnification. The results were evaluated statistically (analysis of variance, Holm-Sidak method, α = .05)., Results: The mean abutment/framework interface gaps were: master cast = 31.63 µm; group I = 45.25 µm; group S = 96.14 µm; group MS = 51.20 µm. No significant difference was detected among the index and modified squared techniques (P = .05)., Conclusion: Under the limitations of this study, the techniques modified squared and index generated more accurate casts than the squared technique.