Spatial distribution of soil organic carbon quality descriptors determining factors that affect its sequestration in Northeast Algeria.

Increasing soil organic carbon (SOC) content is crucial for soil fertility, conservation, and combating climate-related issues by sequestering CO2. While existing studies explore the total content of SOC, few of them investigate the factors that favor its sequestration and the impact of land use type and management. This research aims to study the spatial variation of the total content and the quality or maturity (in terms of aromaticity) of the humic acid (HA) fraction, along with the factors that enhance its formation and conservation for a longer time in the soil. In addition, the study tries to evaluate the performance of the Regression Kriging (RK) method in producing interpolation maps that describe the natural variation of the SOC and its quality with the aim of defining and preventing soil degradation. Finally, the study aims to evaluate the impact of the land use type and the importance of dense vegetation in the sequestration of the organic carbon (OC) in the soil. The analysis of the SOC was performed in northeast Algeria's semi-arid climate, examining content, quality, and chemical composition. Using geostatistical methods (RK), SOC is correlated with most related factors, producing detailed interpolation maps. The results showed that the SOC and its HA fraction (both its total content and its degree of transformation or maturity (measured in terms of aromaticity and structural condensation) are highly correlated to the topography of the area (P < 0.05). Results reveal variations in HAs' composition across land covers. Notably, areas subjected to burning exhibited a 21% increase in HA aromaticity compared to forested regions and a 29% increase relative to cultivated areas. The study highlights that soil cover has a substantial influence on the performance of SOC sequestration, the forested areas have a positive impact on the storage of SOC in the form of HA with a more complex chemical composition that suggests increased aromaticity and resilience. As a whole, the results indicate the potential of geostatistical methods to provide valuable information about the factors that influence the current status and evolution of SOC in the study area.

HIV/AIDS infection in critical care: epidemiological profile and risk factors for mortality in a Colombian cohort.

INTRODUCTION: Outcomes of human immunodeficiency virus (HIV) infected patients admitted to intensive care units (ICU) have improved with antiretroviral therapy (ART). However, whether the outcomes have improved in low- and middle-income countries, paralleling those of high-income countries is unknown. The objective of this study was to describe a cohort of HIV-infected patients admitted to ICU in a middle-income country and identify the risk factors associated with mortality. METHODOLOGY: A cohort study of HIV-infected patients admitted to five ICUs in Medellín, Colombia, between 2009 and 2014 was done. The association of demographic, clinical and laboratory variables with mortality was analyzed using a Poisson regression model with random effects. RESULTS: During this time period, 472 admissions of 453 HIV-infected patients were included. Indications for ICU admission were: respiratory failure (57%), sepsis/septic shock (30%) and central nervous system (CNS) compromise (27%). Opportunistic infections (OI) explained 80% of ICU admissions. Mortality rate was 49%. Factors associated with mortality included hematological malignancies, CNS compromise, respiratory failure, and APACHE II score ≥ 20. CONCLUSIONS: Despite advances in HIV care in the ART era, half of HIV-infected patients admitted to the ICU died. This elevated mortality was associated to underlying disease severity (respiratory failure and APACHE II score ≥ 20), and host conditions (hematological malignancies, admission for CNS compromise). Despite the high prevalence of OIs in this cohort, mortality was not directly associated to OIs.

Underwater versus conventional EMR of large nonpedunculated colorectal lesions: a multicenter randomized controlled trial.

BACKGROUND AND AIMS: Underwater EMR (UEMR) is an alternative procedure to conventional EMR (CEMR) to treat large, nonpedunculated colorectal lesions (LNPCLs). In this multicenter, randomized controlled clinical trial, we aimed to compare the efficacy and safety of UEMR versus CEMR on LNPCLs. METHODS: We conducted a multicenter, randomized controlled clinical trial from February 2018 to February 2020 in 11 hospitals in Spain. A total of 298 patients (311 lesions) were randomized to the UEMR (n = 149) and CEMR (n = 162) groups. The main outcome was the lesion recurrence rate in at least 1 follow-up colonoscopy. Secondary outcomes included technical aspects, en bloc resection rate, R0 resection rates, and adverse events, among others. RESULTS: There were no differences in the overall recurrence rate (9.5% UEMR vs 11.7% CEMR; absolute risk difference, -2.2%; 95% CI, -9.4 to 4.9). However, considering polyp sizes between 20 and 30 mm, the recurrence rate was lower for UEMR (3.4% UEMR vs 13.1% CEMR; absolute risk difference, -9.7%; 95% CI, -19.4 to 0). The R0 resection showed the same tendency, with significant differences favoring UEMR only for polyps between 20 and 30 mm. Overall, UEMR was faster and easier to perform than CEMR. Importantly, the techniques were equally safe. CONCLUSIONS: UEMR is a valid alternative to CEMR for treating LNPCLs and could be considered the first option of treatment for lesions between 20 and 30 mm due to its higher en bloc and R0 resection rates. (Clinical trial registration number: NCT03567746.).

Compound Endoscopic Morphological Features for Identifying Non-Pedunculated Lesions ≥20 mm with Intramucosal Neoplasia.

BACKGROUND: The major limitation of piecemeal endoscopic mucosal resection (EMR) is the inaccurate histological assessment of the resected specimen, especially in cases of submucosal invasion. OBJECTIVE: To classify non-pedunculated lesions ≥20 mm based on endoscopic morphological features, in order to identify those that present intramucosal neoplasia (includes low-grade neoplasia and high-grade neoplasia) and are suitable for piecemeal EMR. DESIGN: A post-hoc analysis from an observational prospective multicentre study conducted by 58 endoscopists at 17 academic and community hospitals was performed. Unbiased conditional inference trees (CTREE) were fitted to analyse the association between intramucosal neoplasia and the lesions' endoscopic characteristics. RESULT: 542 lesions from 517 patients were included in the analysis. Intramucosal neoplasia was present in 484 of 542 (89.3%) lesions. A conditional inference tree including all lesions' characteristics assessed with white light imaging and narrow-band imaging (NBI) found that ulceration, pseudodepressed type and sessile morphology changed the accuracy for predicting intramucosal neoplasia. In ulcerated lesions, the probability of intramucosal neoplasia was 25% (95%CI: 8.3-52.6%; p < 0.001). In non-ulcerated lesions, its probability in lateral spreading lesions (LST) non-granular (NG) pseudodepressed-type lesions rose to 64.0% (95%CI: 42.6-81.3%; p < 0.001). Sessile morphology also raised the probability of intramucosal neoplasia to 86.3% (95%CI: 80.2-90.7%; p < 0.001). In the remaining 319 (58.9%) non-ulcerated lesions that were of the LST-granular (G) homogeneous type, LST-G nodular-mixed type, and LST-NG flat elevated morphology, the probability of intramucosal neoplasia was 96.2% (95%CI: 93.5-97.8%; p < 0.001). CONCLUSION: Non-ulcerated LST-G type and LST-NG flat elevated lesions are the most common non-pedunculated lesions ≥20 mm and are associated with a high probability of intramucosal neoplasia. This means that they are good candidates for piecemeal EMR. In the remaining lesions, further diagnostic techniques like magnification or diagnostic +/- therapeutic endoscopic submucosal dissection should be considered.

Micro-patterned deposition of MoS2 ultrathin-films by a controlled droplet dragging approach.

Micropatterning of transition metal dichalcogenide (TMDC) ultrathin-films and monolayers has been demonstrated by various multi-step approaches. However, directly achieving a patterned growth of TMDC films is still considered to be challenging. Here, we report a solution-based approach for the synthesis of patterned MoS2 layers by dragging a precursor solution droplet with variable velocities across a substrate. Utilizing the pronounced shearing velocity dependence in a Landau-Levich deposition regime, MoS2 films with a spatially modulated thickness with alternating mono/bi- and few-layer regions are obtained after precursor annealing. Generally, the presented facile methodology allows for the direct preparation of micro-structured functional materials, extendable to other TMDC materials and even van der Waals heterostructures.

Calidad de la preparación para la colonoscopia en un entorno de práctica clínica privada / The quality of colonoscopy preparation in a private clinical practice setting

No disponible

The quality of colonoscopy preparation in a private clinical practice setting.

No data are available on the quality of the preparation for colonoscopy in private medicine in Spain. We report a retrospective study of the efficacy and tolerability of bowel preparation in the standard clinical practice in a private center.

Quantitative forecasting black (pyrogenic) carbon in soils by chemometric analysis of infrared spectra.

A detailed and global quantitative assessment of the distribution of pyrogenic carbon (PyC) in soils remains unaccounted due to the current lack of unbiased methods for its routine quantification in environmental samples. Conventional oxidation with potassium dichromate has been reported as a useful approach for the determination of recalcitrant C in soils. However, its inaccuracy due to the presence of residual non-polar but still non-PyC requires additional analysis by 13C solid-state nuclear magnetic resonance (NMR) spectroscopy, which is expensive and time consuming. The goal of this work is to examine the possibility of applying infrared (IR) spectroscopy as a potential alternative. Different soil type samples (paddy soil, Histic Humaquept, Leptosol and Cambisol) have been used. The soils were digested with potassium dichromate to determine the PyC content in environmental samples. Partial Least Squares (PLS) regression was used to build calibration models to predict PyC from IR spectra. A set of artificially produced samples rich in PyC was used as reference to observe in detail the IR bands derived from aromatic structures resistant to dichromate oxidation, representing black carbon. The results showed successful PLS forecasting of PyC in the different samples by using spectra in the 1800-400 cm-1 range. This lead to significant (P < 0.05) cross-validation coefficients for PyC, determined as the aryl C content of the oxidized residue. The Variable Importance for Projection (VIP) traces for the corresponding PLS regression models plotted in the whole IR range indicates the extent to which each IR band contributes to explain the aryl C and PyC contents. In fact, forecasting PyC in soils requires information from several IR regions. In addition to the expected IR bands corresponding to aryl C, other bands are informing about the patterns of oxygen-containing functional groups and the mineralogical composition characteristic of the soils with greater black carbon storage capacity. The VIP traces of the charred biomass samples confirm that aromatic bands (1620 and 1510 cm-1) are the most important in the prediction model for PyC-rich samples. These facts suggest that the mid-IR spectroscopy could be a potential tool to estimate the black carbon.

Chemometric assessment of soil organic matter storage and quality from humic acid infrared spectra.

The knowledge of biogeochemical mechanisms involved in soil organic carbon (SOC) storage is crucial to control its release to the atmosphere. In particular, the chemical composition of soil organic matter (SOM) plays an important role in the performance of the C storage and resilience in soils. The structural information provided by infrared spectroscopy (IR) of soil humic acid (HA) was used in the assessment of the C storage potential of 35 Spanish soils. Partial least squares (PLS) regression using the intensities of the points of the IR spectra of the HAs (4000-400 cm-1) as descriptors shows that a relationship exists between IR spectral pattern and the SOC content. This was also the case for E4 (humification index based on HA optical density at 465 nm). In addition, the chemical characteristics of the HAs correlated with the SOC levels were identified from digital data treatments of the IR spectra. Additional application of principal component analysis (PCA) and multidimensional scaling (MDS) suggested that bands assigned to carboxyl and amide structures were characteristic in HAs from soils with low C content, whereas HA spectra from soils with high C levels showed a conspicuous band pattern suggesting structural units of lignin from slightly transformed plant residues. The spectral profiles were analyzed in detail by an approach based on digital subtraction of IR spectra obtained by averaging those from HAs extracted from soils in the upper and lower quartiles of the SOC distribution. The results showed that significant relationships exist between the molecular composition of HAs and SOC levels and E4 values in a way in which aromatic, carboxyl and amide groups were predominant in HAs from soils with low SOC content, whereas lignin-derived structures were more characteristic of HAs from soils with high SOC content.

Randomized Clinical Trial: A Normocaloric Low-Fiber Diet the Day Before Colonoscopy Is the Most Effective Approach to Bowel Preparation in Colorectal Cancer Screening Colonoscopy.

BACKGROUND: Clinical guidelines recommend either a clear-liquid diet or a low-fiber diet for colonoscopy preparation. Participants in a screening program are usually motivated healthy individuals in which a good tolerability is important to improve adherence to potential surveillance colonoscopies. OBJECTIVE: Our aim was to assess whether or not a normocaloric low-fiber diet followed the day before a screening colonoscopy compromises the efficacy of bowel cleansing and may improve the tolerability of bowel preparation. DESIGN: This is a randomized, endoscopist-blinded, noninferiority clinical trial. SETTINGS: The study was conducted at a tertiary care center. PATIENTS: A total of 276 consecutive participants of the Barcelona colorectal cancer screening program were included. INTERVENTION: Participants were randomly assigned to a clear-liquid diet or a normocaloric low-fiber diet the day before the colonoscopy. Both groups received 4 L of polyethylene glycol in a split-dose regimen. MAIN OUTCOME MEASURES: Primary outcome was the adequate bowel preparation rate measured with the Boston bowel preparation scale. Secondary outcomes included tolerability, fluid-intake perception, hunger, side effects, and acceptability. RESULTS: Participants in both groups were similar in baseline characteristics. Adequate bowel preparation was achieved in 89.1% vs 95.7% in clear-liquid diet and low-fiber diet groups, showing not only noninferiority, but also superiority (p = 0.04). Low-fiber diet participants reported less fluid-intake perception (p = 0.04) and less hunger (p = 0.006), with no differences in bloating or nausea. LIMITATIONS: The single-center design of the study could limit the external validity of the results. The present findings may not be comparable to other clinical settings. CONCLUSION: A normocaloric low-fiber diet the day before a screening colonoscopy achieved better results than a clear-liquid diet in terms of adequate colon preparation. Moreover, it also improved the perception of hunger and excessive fluid intake. Registered at clinicaltrials.gov: NCT02401802. See Video Abstract at http://links.lww.com/DCR/A829.

Autopercepción del estado de salud en pensionados por complicaciones de diabetes mellitus en Guadalajara, México / Self-perception of health status in people retired due to diabetes mellitus complications from Guadalajara, Mexico

RESUMEN Objetivo Evaluar la autopercepción del estado de salud (APES) de los pensionados por complicaciones de la diabetes mellitus, y que características sociodemográficas, familiares, laborales y clínicas de éstos están asociadas a dichas variables. Métodos Estudio transversal analítico en un universo 240 pensionados que aceptaron participar. Se evaluó la APES con el Cuestionario EuroQol-5D en español, y se incluyeron variables sociodemográficas, familiares, laborales y clínicas. Resultados Se estudiaron 240 pensionados con edad media 53,43 ± 8,16 años, 94,3% masculinos y 5,7% femeninos. Se encontró que el 53,4% refiere una APES regular, mala o muy mala. Se halló asociación significativa entre mala APES y vida laboral ≤30 años OR=6,00 (IC95% 1,27, 28,26) e insuficiencia renal crónica OR=7,00 (IC95% 1,39,35,35). No se encontraron modelos explicativos mediante regresión logística. Conclusiones La frecuencia de APES mala fue elevada en la muestra de pensionados por complicaciones de la diabetes mellitus. Se requieren estudios con muestras más amplias para mejores conclusiones.(AU)

ABSTRACT Objective To evaluate self-perception of health status (APES by its Spanish acronym) of people retired due to complications of diabetes mellitus, and what socio-demographic, family, work and clinical characteristics are associated to these variables. Materials and Methods Analytical, cross-sectional study in a universe of 240 pensioners who agreed to participate. The APES was evaluated with the EuroQol-5D questionnaire in Spanish, and socio-demographic, family, work and clinical variables were included. Results 240 pensioners with a mean age of 53.43 ± 8.16 years (94.29% male and 5.71% female) were studied. It was found that 53.4% reported regular, poor or very poor APES. A significant association between poor APES and work life ≤30 years (OR=6.00; 95%CI: 1.27, 28.26) and chronic renal failure (OR=7.00; 95%CI: 1.39, 35.35) was found. No explanatory models were found through logistic regression. No explanatory models were found by logistic regression. Conclusion The frequency of poor APES was high in the sample of patients with diabetes. Studies with larger samples are required for better conclusions.(AU)

[Self-perception of health status in people retired due to diabetes mellitus complications from Guadalajara, Mexico]. / Autopercepción del estado de salud en pensionados por complicaciones de diabetes mellitus en Guadalajara, México.

OBJECTIVE: To evaluate self-perception of health status (APES by its Spanish acronym) of people retired due to complications of diabetes mellitus, and what socio-demographic, family, work and clinical characteristics are associated to these variables. MATERIALS AND METHODS: Analytical, cross-sectional study in a universe of 240 pensioners who agreed to participate. The APES was evaluated with the EuroQol-5D questionnaire in Spanish, and socio-demographic, family, work and clinical variables were included. RESULTS: 240 pensioners with a mean age of 53.43 ± 8.16 years (94.29% male and 5.71% female) were studied. It was found that 53.4% reported regular, poor or very poor APES. A significant association between poor APES and work life ≤30 years (OR=6.00; 95%CI: 1.27, 28.26) and chronic renal failure (OR=7.00; 95%CI: 1.39, 35.35) was found. No explanatory models were found through logistic regression. No explanatory models were found by logistic regression. CONCLUSION: The frequency of poor APES was high in the sample of patients with diabetes. Studies with larger samples are required for better conclusions.

OBJETIVO: Evaluar la autopercepción del estado de salud (APES) de los pensionados por complicaciones de la diabetes mellitus, y que características sociodemográficas, familiares, laborales y clínicas de éstos están asociadas a dichas variables. MÉTODOS: Estudio transversal analítico en un universo 240 pensionados que aceptaron participar. Se evaluó la APES con el Cuestionario EuroQol-5D en español, y se incluyeron variables sociodemográficas, familiares, laborales y clínicas. RESULTADOS: Se estudiaron 240 pensionados con edad media 53,43 ± 8,16 años, 94,3% masculinos y 5,7% femeninos. Se encontró que el 53,4% refiere una APES regular, mala o muy mala. Se halló asociación significativa entre mala APES y vida laboral ≤30 años OR=6,00 (IC95% 1,27, 28,26) e insuficiencia renal crónica OR=7,00 (IC95% 1,39,35,35). No se encontraron modelos explicativos mediante regresión logística. CONCLUSIONES: La frecuencia de APES mala fue elevada en la muestra de pensionados por complicaciones de la diabetes mellitus. Se requieren estudios con muestras más amplias para mejores conclusiones.

Accuracy of the Narrow-Band Imaging International Colorectal Endoscopic Classification System in Identification of Deep Invasion in Colorectal Polyps.

BACKGROUND & AIMS: T1 colorectal polyps with at least 1 risk factor for metastasis to lymph node should be treated surgically and are considered endoscopically unresectable. Optical analysis, based on the Narrow-Band Imaging International Colorectal Endoscopic (NICE) classification system, is used to identify neoplasias with invasion of the submucosa that require endoscopic treatment. We assessed the accuracy of the NICE classification, along with other morphologic characteristics, in identifying invasive polyps that are endoscopically unresectable (have at least 1 risk factor for metastasis to lymph node). METHODS: We performed a multicenter, prospective study of data collected by 58 endoscopists, from 1634 consecutive patients (examining 2123 lesions) at 17 university and community hospitals in Spain from July 2014 through June 2016. All consecutive lesions >10 mm assessed with narrow-band imaging were included. The primary end point was the accuracy of the NICE classification for identifying lesions with deep invasion, using findings from histology analysis as the reference standard. Conditional inference trees were fitted for the analysis of diagnostic accuracy. RESULTS: Of the 2123 lesions analyzed, 89 (4.2%) had features of deep invasion and 91 (4.3%) were endoscopically unresectable. The NICE classification system identified lesions with deep invasion with 58.4% sensitivity (95% CI, 47.5-68.8), 96.4% specificity (95% CI, 95.5-97.2), a positive-predictive value of 41.6% (95% CI, 32.9-50.8), and a negative-predictive value of 98.1% (95% CI, 97.5-98.7). A conditional inference tree that included all variables found the NICE classification to most accurately identify lesions with deep invasion (P < .001). However, pedunculated morphology (P < .007), ulceration (P = .026), depressed areas (P < .001), or nodular mixed type (P < .001) affected accuracy of identification. Results were comparable for identifying lesions that were endoscopically unresectable. CONCLUSIONS: In an analysis of 2123 colon lesions >10 mm, we found the NICE classification and morphologic features identify those with deep lesions with >96% specificity-even in non-expert hands and without magnification. ClinicalTrials.gov number NCT02328066.

Educational intervention to improve the competence of Mexican physicians to provide nutritional management for diabetes mellitus type 2 / Intervención educativa para mejorar la competencia de médicos mexicanos para manejar nutricionalmente diabetes mellitus Tipo 2

ABSTRACT Objective To evaluate the effect of a participative educational intervention on the clinical competence of Mexican family physicians regarding the nutritional management of patients with diabetes mellitus Type 2. Materials and Methods Quasi-experimental study with a before-and-after control group. Convenience sample included 60 family physicians distributed in two social security primary health care units, randomly selected: 30 in the "A" unit and 30 in the "B" unit. Unit "A" was assigned randomly as control group, and "B" unit as intervention group. The intervention consisted of a theoretical-practical course-workshop that lasted six months where real cases were discussed and solved. Clinical competence was evaluated by means of an instrument designed ex professo, with a maximum theoretical value of 100 and 94% reliability according to the Kuder-Richardson test. Medians of clinical competence were compared among groups, before and after intervention, using the Mann-Whitney U test, while frequencies distribution of clinical competence level were analyzed with the Kolmogorov-Smirnov test (p≤0.05). Results Overall medians and intervals for unit "A" were 28 (9-45) pre-intervention and 34 (11-51) pos-intervention, with before-after difference p>0.05; for unit "B", values were 32 (12-50) pre-intervention, 61 (36-82) pos-intervention, and before-after difference p≤0.05. No significant differences were found among groups pre-intervention (p>0.05), although they were observed pos-intervention (p≤0.05). Conclusions The educational intervention evaluated proved to improve, in a statistically significant way, the overall and by dimensions clinical competence level of Mexican family physicians for nutritional management of patients with diabetes mellitus type 2.(AU)

RESUMEN Objetivo Evaluar el efecto de una intervención educativa participativa sobre la competencia clínica de médicos familiares mexicanos para el manejo nutricio de pacientes con diabetes mellitus Tipo 2. Método Estudio cuasiexperimental con grupo control antes-después. Se estudió una muestra por conveniencia de 60 médicos familiares distribuidos en dos unidades médicas de atención primaria de seguridad social elegidas al azar, 30 en la "A" y 30 en la "B". La unidad "A" fue designada grupo control, y la "B" de intervención. La intervención consistió en un curso-taller teórico-práctico que duró seis meses, donde se discutieron y resolvieron casos reales. La competencia clínica se evaluó mediante un instrumento diseñado ex professo, con un valor teórico máximo de 100, y una fiabilidad de 94% según prueba de Kuder-Richardson. Se compararon las medianas de competencia clínica entre grupos antes y después mediante la prueba U de Mann-Whitney, y cinco las distribuciones de frecuencias de los niveles de competencia clínica mediante la prueba de Kolmogórov-Smirnov (p≤0,05). Resultados Medianas e intervalos de la calificación global: unidad "A" 28 (9-45) pre-intervención, 34 (11-51) pos-intervención, diferencia antes-después p≤0,05; unidad "B" 32 (12-50) pre-intervención, 61 (36-82) pos-intervención, diferencia antes-después p≤0,05. No se encontró diferencia significativa entre los grupos pre-intervención (p>0,05), y si pos-intervención (p≤0,05). Conclusiones La intervención educativa evaluada demostró mejorar, de forma estadísticamente significativa, el nivel de competencia clínica global y por dimensión, de médicos familiares mexicanos para el manejo nutricio de pacientes con diabetes mellitus tipo 2.(AU)

Representaciones sociales de adolescentes mexicanas embarazadas sobre el puerperio, la lactancia y los cuidados del recién nacido / Social representations of Mexican pregnant teenagers about the puerperal care, lactation, and newborn care

Resumen: Introducción: Los cuidados durante el puerperio y la alimentación del recién nacido están guiados por significados culturales afianzados entre las mujeres, por lo que es importante conocerlos e identificar cómo se adquieren y perpetúan. En este tenor, se estudiaron las representaciones sociales que tienen adolescentes mexicanas embarazadas sobre el puerperio, la lactancia y el cuidado del recién nacido. Métodos: Se realizó un estudio interpretativo basado en los principios de la teoría de las representaciones sociales. Se realizaron entrevistas para obtener información de 30 adolescentes mexicanas que asistieron a control prenatal al área de ginecoobstetricia en un hospital de segundo nivel de atención durante 2015. Se aplicaron estrategias de análisis de contenido clásico para analizar la información; este proceso consistió en codificar y categorizar la información. También se elaboró un mapa conceptual para describir las representaciones sociales encontradas. Resultados: Se identificaron 190 códigos y tres representaciones sociales: «lactancia: práctica mitificada¼, «los recién nacidos son frágiles¼ y «madre e hijo deben sincronizarse¼. Conclusiones: Se identificaron tres representaciones sociales que explicaron las prácticas de las adolescentes hacia la lactancia y el cuidado de ellas y sus hijos, adquiridas mediante la comunicación familiar y afianzadas por la necesidad de apoyo debido a ausencia temporal o permanente de pareja, crisis personales motivadas por los cambios corporales, miedo a sufrir cambios por la lactancia y desconocimiento sobre cómo llevar a cabo la lactancia y los cuidados durante el puerperio.

Abstract: Background: Puerperal care and feeding of the newborn are guided by entrenched cultural meanings between women, so it is important to know and identify how they are acquired and perpetuated. Regarding this knowledge, the social representations that Mexican pregnant teenagers have about puerperium, lactation and newborn care were studied. Methods: An interpretative study was made based on principles of the theory of social representations. Interviews were conducted to obtain information from 30 Mexican adolescents who attended prenatal care at the gynecological obstetrics area in a second-level hospital during 2015. Classical content analysis strategies were applied to analyze the information; this process consisted of coding and categorizing information. A conceptual map was also developed to describe the social representations found. Results: In this study, 190 codes and three social representations were identified: "breastfeeding is a practice based on myths", "newborns are fragile" and "mother and child must be synchronized". Conclusions: Three social representations were identified that explain the practices of adolescents towards breastfeeding and the care of them and their children, which were acquired through family communication and strengthened by the need for support due to the temporary or permanent absence of the couple, personal crises motivated by bodily changes, fear of new modifications due to breastfeeding and ignorance about how carry out breastfeeding and care during the puerperium.

[Social representations of Mexican pregnant teenagers about the puerperal care, lactation, and newborn care]. / Representaciones sociales de adolescentes mexicanas embarazadas sobre el puerperio, la lactancia y los cuidados del recién nacido.

Background: Puerperal care and feeding of the newborn are guided by entrenched cultural meanings between women, so it is important to know and identify how they are acquired and perpetuated. Regarding this knowledge, the social representations that Mexican pregnant teenagers have about puerperium, lactation and newborn care were studied. Methods: An interpretative study was made based on principles of the theory of social representations. Interviews were conducted to obtain information from 30 Mexican adolescents who attended prenatal care at the gynecological obstetrics area in a second-level hospital during 2015. Classical content analysis strategies were applied to analyze the information; this process consisted of coding and categorizing information. A conceptual map was also developed to describe the social representations found. Results: In this study, 190 codes and three social representations were identified: "breastfeeding is a practice based on myths", "newborns are fragile" and "mother and child must be synchronized". Conclusions: Three social representations were identified that explain the practices of adolescents towards breastfeeding and the care of them and their children, which were acquired through family communication and strengthened by the need for support due to the temporary or permanent absence of the couple, personal crises motivated by bodily changes, fear of new modifications due to breastfeeding and ignorance about how carry out breastfeeding and care during the puerperium.

Introducción: Los cuidados durante el puerperio y la alimentación del recién nacido están guiados por significados culturales afianzados entre las mujeres, por lo que es importante conocerlos e identificar cómo se adquieren y perpetúan. En este tenor, se estudiaron las representaciones sociales que tienen adolescentes mexicanas embarazadas sobre el puerperio, la lactancia y el cuidado del recién nacido. Métodos: Se realizó un estudio interpretativo basado en los principios de la teoría de las representaciones sociales. Se realizaron entrevistas para obtener información de 30 adolescentes mexicanas que asistieron a control prenatal al área de ginecoobstetricia en un hospital de segundo nivel de atención durante 2015. Se aplicaron estrategias de análisis de contenido clásico para analizar la información; este proceso consistió en codificar y categorizar la información. También se elaboró un mapa conceptual para describir las representaciones sociales encontradas. Resultados: Se identificaron 190 códigos y tres representaciones sociales: «lactancia: práctica mitificada¼, «los recién nacidos son frágiles¼ y «madre e hijo deben sincronizarse¼. Conclusiones: Se identificaron tres representaciones sociales que explicaron las prácticas de las adolescentes hacia la lactancia y el cuidado de ellas y sus hijos, adquiridas mediante la comunicación familiar y afianzadas por la necesidad de apoyo debido a ausencia temporal o permanente de pareja, crisis personales motivadas por los cambios corporales, miedo a sufrir cambios por la lactancia y desconocimiento sobre cómo llevar a cabo la lactancia y los cuidados durante el puerperio.

Educational intervention to improve the competence of Mexican physicians to provide nutritional management for diabetes mellitus type 2.

OBJECTIVE: To evaluate the effect of a participative educational intervention on the clinical competence of Mexican family physicians regarding the nutritional management of patients with diabetes mellitus Type 2. MATERIALS AND METHODS: Quasi-experimental study with a before-and-after control group. Convenience sample included 60 family physicians distributed in two social security primary health care units, randomly selected: 30 in the "A" unit and 30 in the "B" unit. Unit "A" was assigned randomly as control group, and "B" unit as intervention group. The intervention consisted of a theoretical-practical course-workshop that lasted six months where real cases were discussed and solved. Clinical competence was evaluated by means of an instrument designed ex professo, with a maximum theoretical value of 100 and 94% reliability according to the Kuder-Richardson test. Medians of clinical competence were compared among groups, before and after intervention, using the Mann-Whitney U test, while frequencies distribution of clinical competence level were analyzed with the Kolmogorov-Smirnov test (p≤0.05). RESULTS: Overall medians and intervals for unit "A" were 28 (9-45) pre-intervention and 34 (11-51) pos-intervention, with before-after difference p>0.05; for unit "B", values were 32 (12-50) pre-intervention, 61 (36-82) pos-intervention, and before-after difference p≤0.05. No significant differences were found among groups pre-intervention (p>0.05), although they were observed pos-intervention (p≤0.05). CONCLUSIONS: The educational intervention evaluated proved to improve, in a statistically significant way, the overall and by dimensions clinical competence level of Mexican family physicians for nutritional management of patients with diabetes mellitus type 2.

A vapor-phase-assisted growth route for large-scale uniform deposition of MoS2 monolayer films.

In this work a vapor-phase-assisted approach for the synthesis of monolayer MoS2 is demonstrated, based on the sulfurization of thin MoO3-x precursor films in an H2S atmosphere. We discuss the co-existence of various possible growth mechanisms, involving solid-gas and vapor-gas reactions. Different sequences were applied in order to control the growth mechanism and to obtain monolayer films. These variations include the sample temperature and a time delay for the injection of H2S into the reaction chamber. The optimized combination allows for tuning the process route towards the potentially more favorable vapor-gas reactions, leading to an improved material distribution on the substrate surface. Raman and photoluminescence (PL) spectroscopy confirm the formation of ultrathin MoS2 films on SiO2/Si substrates with a narrow thickness distribution in the monolayer range on length scales of a few millimeters. Best results are achieved in a temperature range of 950-1000 °C showing improved uniformity in terms of Raman and PL line shapes. The obtained films exhibit a PL yield similar to mechanically exfoliated monolayer flakes, demonstrating the high optical quality of the prepared layers.

OUTCOMES OF PARS PLANA VITRECTOMY FOR MACULAR HOLE IN PATIENTS WITH UVEITIS.

PURPOSE: Inflammatory macular hole is a rare complication of uveitis, and data on surgical outcomes of closure are scarce. The purpose of this study is to evaluate the anatomical and visual outcomes of conventional pars plana vitrectomy for patients with uveitis. METHODS: Noncomparative, interventional, and consecutive case series from 6 vitreoretinal surgical centers from 2007 to 2015. Twenty eyes of 19 patients were included with 4 patients separated as viral retinitis. The primary outcome was change in best-corrected visual acuity at Month 3. Secondary outcomes were closure of the macular hole and postoperative optical coherence tomography characteristics. RESULTS: All eyes underwent conventional three-port pars plana vitrectomy with indocyanine green-assisted internal limiting membrane peeling. Mean Snellen best-corrected visual acuity improved from 20/200 to 20/63 (P = 0.01 for a difference in logarithm of the minimum angle of resolution) at Month 3. Twelve (75%) of patients achieved 2 or more lines of visual acuity improvement by postoperative Month 3. Surgery resulted in decreased epiretinal membrane (P = 0.002), intraretinal fluid (P < 0.001), subretinal fluid (P = 0.029), central subfield thickness (P < 0.001), and central cube volume (P = 0.041). Surgical intervention achieved anatomical success, as measured by macular hole closure, in 13 (81%) of patients at postoperative Month 3. CONCLUSION: Patients with inflammatory macular hole respond well to conventional surgery, with good anatomical and visual acuity outcomes.