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As vaccines have become available for COVID-19, it is important to understand factors that may impact response. The objective of this study is to describe vaccine response in a well-characterized Northern California cohort, including differences in side-effects and antibody response by vaccine type, sex, and age, as well as describe responses in subjects with pre-existing health conditions that are known risk factors for more severe COVID-19 infection. From July 2020 to March 2021, ∼5,500 adults from the East Bay Area in Northern California were followed as part of a longitudinal cohort study. Comprehensive questionnaire data and biospecimens for COVID-19 antibody testing were collected at multiple time-points. All subjects were at least 18 years of age and members of the East-Bay COVID-19 cohort who answered questionnaires related to vaccination status and side-effects at two time-points. Three vaccines, Moderna (2 doses), Pfizer-BioNTech (2 doses), and Johnson & Johnson (single dose), were examined as exposures. Additionally, pre-existing health conditions were assessed. The main outcomes of interest were anti-SARS-CoV-2 Spike antibody response (measured by S/C ratio in the Ortho VITROS assay) and self-reporting of 11 potential vaccine side effects. When comparing both doses of the Moderna vaccine to respective doses of Pfizer-BioNTech, participants receiving the Moderna vaccine had higher odds of many reported side-effects. The same was true comparing the single-dose Johnson & Johnson vaccine to dose 2 of the Pfizer-BioNTech vaccine. The antibody S/C ratio also increased with each additional side-effect after the second dose. S/C ratios after vaccination were lower in participants aged 65 and older, and higher in females. At all vaccination timepoints, Moderna vaccine recipients had a higher S/C ratio. Individuals who were fully vaccinated with Pfizer-BioNTech had a 72.4% lower S/C ratio compared to those who were fully vaccinated with Moderna. Subjects with asthma, diabetes, and cardiovascular disease all demonstrated more than a 20% decrease in S/C ratio. In support of previous findings, we show that antibody response to the Moderna vaccine is higher than the Pfizer-BioNTech vaccine. We also observed that antibody response was associated with side-effects, and participants with a history of asthma, diabetes, and cardiovascular disease had lower antibody responses. This information is important to consider as further vaccines are recommended.

IRET During the ongoing coronavirus disease (COVID-19) pandemic, farmworkers in the United States are consid ered essential personnel and continue in-person work. We conducted prospective surveillance for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and antibody prevalence among farmwork ers in Salinas Valley, California, during June 15–No vember 30, 2020. We observed 22.1% (1,514/6,864) positivity for SARS-CoV-2 infection among farmwork ers compared with 17.2% (1,255/7,305) among other adults from the same communities (risk ratio 1.29, 95% CI 1.20–1.37). In a nested study enrolling 1,115 farm workers, prevalence of current infection was 27.7% among farmworkers reporting >1 COVID-19 symptom and 7.2% among farmworkers without symptoms (ad justed odds ratio 4.16, 95% CI 2.85–6.06). Prevalence of SARS-CoV-2 antibodies increased from 10.5% (95% CI 6.0%–18.4%) during July 16–August 31 to 21.2% (95% CI 16.6%–27.4%) during November 1–30. High SARS-CoV-2 infection prevalence among farmworkers underscores the need for vaccination and other pre ventive interventions. Durante la pandemia actual de la enfermedad por coronavirus (COVID-19), los trabajadores agrícolas en los Estados Unidos son considerados personal esencial y continúan trabajando en persona. Realizamos una vigilancia prospectiva de la infección por coronavirus 2 (SARS-CoV-2) del síndrome respiratorio agudo severo y la prevalencia de anticuerpos entre los trabajadores agrícolas en Salinas Valley, California, del 15 de junio al 30 de noviembre de 2020. Observamos 22.1% (1,514 / 6,864) positividad para la infección por SARS-CoV-2 entre los trabajadores agrícolas en comparación con el 17.2% (1.255 / 7.305) entre otros adultos de las mismas comunidades (razón de riesgo 1.29, IC del 95%: 1.20–1.37). En un estudio anidado que inscribió a 1115 trabajadores agrícolas, la prevalencia de la infección actual fue del 27,7% entre los trabajadores agrícolas que informaron> 1 síntoma de COVID-19 y del 7,2% entre los trabajadores agrícolas sin síntomas (razón de probabilidades ajustada 4,16, IC del 95%: 2,85–6,06). La prevalencia de anticuerpos contra el SARS-CoV-2 aumentó del 10,5% (IC del 95%: 6,0% al 18,4%) del 16 de julio al 31 de agosto al 21,2% (IC del 95%: 16,6% al 27,4%) del 1 al 30 de noviembre. La alta prevalencia de la infección por SARS-CoV-2 entre los trabajadores agrícolas subraya la necesidad de vacunación y otras intervenciones preventivas. Universidad de California, Estados Unidos. Universidad Nacional, Costa Rica. Clínica de Salud del Valle de Salinas, Estados Unidos. Escuela de Higiene y Medicina Tropical de Londres, Reino Unido. Universidad de Arizona, Estados Unidos. Instituto Regional de Estudios en Sustancias Tóxicas

This work establishes a correlation between the selectivity of hydrogen-bonding interactions and the functionality of micelle-containing layer-by-layer (LbL) assemblies. Specifically, we explore LbL films formed by assembly of poly(methacrylic acid) (PMAA) and upper critical solution temperature block copolymer micelles (UCSTMs) composed of poly(acrylamide-co-acrylonitrile) P(AAm-co-AN) cores and polyvinylpyrrolidone (PVP) coronae. UCSTMs had a hydrated diameter of ∼380 nm with a transition temperature between 45 and 50 °C, regardless of solution pH. Importantly, micelles were able to hydrogen-bond with PMAA, with the critical interaction pH being temperature dependent. To better understand the thermodynamic nature of these interactions, in depth studies using isothermal titration calorimetry (ITC) were conducted. ITC reveals opposite signs of enthalpies for binding of PMAA with micellar coronae vs. with the cores. Moreover, ITC indicates that pH directs the interactions of PMAA with micelles, selectively enabling binding with the micellar corona at pH 4 or with both the corona and the core at pH 3. We then explore UCSTM/PMAA LbL assemblies and show that the two distinct modes of PMAA interaction with the micelles (i.e. whether or not PMAA binds with the core) had significant effects on the film composition, structure, and functionality. Consistent with PMAA hydrogen bonding with the P(AAm-co-AN) micellar cores, a significantly higher fraction of PMAA was found within the films assembled at pH 3 compared to pH 4 by both spectroscopic ellipsometry and neutron reflectometry. Selective interaction of PMAA with PVP coronae of the assembled micelles, achieved by the emergence of partial ionization of PMAA at pH 4 was critical for preserving film functionality demonstrated as temperature-controlled swelling and release of a model small molecule, pyrene. The work done here can be applied to a multitude of assembled polymer systems in order to predict suppression/retention of their stimuli-responsive behavior.

Serological surveillance studies of infectious diseases provide population-level estimates of infection and antibody prevalence, generating crucial insight into population-level immunity, risk factors leading to infection, and effectiveness of public health measures. These studies traditionally rely on detection of pathogen-specific antibodies in samples derived from venipuncture, an expensive and logistically challenging aspect of serological surveillance. During the COVID-19 pandemic, guidelines implemented to prevent the spread of SARS-CoV-2 infection made collection of venous blood logistically difficult at a time when SARS-CoV-2 serosurveillance was urgently needed. Dried blood spots (DBS) have generated interest as an alternative to venous blood for SARS-CoV-2 serological applications due to their stability, low cost, and ease of collection; DBS samples can be self-generated via fingerprick by community members and mailed at ambient temperatures. Here, we detail the development of four DBS-based SARS-CoV-2 serological methods and demonstrate their implementation in a large serological survey of community members from 12 cities in the East Bay region of the San Francisco metropolitan area using at-home DBS collection. We find that DBS perform similarly to plasma/serum in enzyme-linked immunosorbent assays and commercial SARS-CoV-2 serological assays. In addition, we show that DBS samples can reliably detect antibody responses months postinfection and track antibody kinetics after vaccination. Implementation of DBS enabled collection of valuable serological data from our study population to investigate changes in seroprevalence over an 8-month period. Our work makes a strong argument for the implementation of DBS in serological studies, not just for SARS-CoV-2, but any situation where phlebotomy is inaccessible. IMPORTANCE Estimation of community-level antibody responses to SARS-CoV-2 from infection or vaccination is critical to inform public health responses. Traditional studies of antibodies rely on collection of blood via venipuncture, an invasive procedure not amenable to pandemic-related social-distancing measures. Dried blood spots (DBS) are an alternative to venipuncture, since they can be self-collected by study participants at home and do not require refrigeration for shipment or storage. However, DBS-based assays to measure antibody levels to SARS-CoV-2 have not been widely utilized. Here, we show that DBS are comparable to blood as a sampling method for antibody responses to SARS-CoV-2 infection and vaccination over time measured using four distinct serological assays. The DBS format enabled antibody surveillance in a longitudinal cohort where study participants self-collected samples, ensuring the participants' safety during an ongoing pandemic. Our work demonstrates that DBS are an excellent sampling method for measuring antibody responses whenever venipuncture is impractical.

Key Points Question What are the risk factors associated with SARS-CoV-2 infection among farmworkers in California? Findings In this cross-sectional study of 1107 farmworkers, both household and workplace risk factors, including living with children aged 5 years or younger or unrelated roommates and living or working with an individual with known or suspected COVID-19, were associated with positive results on transcription-mediated amplification tests and immunoglobulin G tests for SARS-CoV-2 infection. Meaning These findings suggest that urgent distribution of vaccines to farmworkers and intervention on modifiable risk factors for SARS-CoV-2 infection are warranted given this population’s increased risk and the essential nature of their work., This cross-sectional study identifies risk factors associated with SARS-CoV-2 infection among farmworkers in California., Importance Essential workers in agriculture and food production have been severely affected by the ongoing COVID-19 pandemic. Objective To identify risk factors associated with SARS-CoV-2 infection among farmworkers in California. Design, Setting, and Participants This cross-sectional study invited farmworkers in California’s Salinas Valley (Monterey County) receiving transcription-mediated amplification (TMA) tests for SARS-CoV-2 infection at federally qualified community clinics and community sites to participate. Individuals were eligible if they were not pregnant, were 18 years or older, had conducted farmwork since the pandemic started, and were proficient in English or Spanish. Survey data were collected and SARS-CoV-2 tests were conducted among participants from July 16 to November 30, 2020. Exposures Sociodemographic, household, community, and workplace characteristics. Main Outcomes and Measures TMA- and immunoglobulin G (IgG)–positive SARS-CoV-2 infection. Results A total of 1107 farmworkers (581 [52.5%] women; mean [SD] age, 39.7 [12.6] years) were included in these analyses. Most participants were born in Mexico (922 [83.3%]), were married or living with a partner (697 [63.0%]), and worked in the fields (825 [74.5%]). Overall, 118 of 911 (13.0%) had a positive result on their TMA test for SARS-CoV-2 infection, whereas 201 of 1058 (19.0%) had antibody evidence of infection. In multivariable analyses accounting for recruitment venue and enrollment period, the incidence of TMA-positive SARS-CoV-2 infection was higher among those with lower than primary school–level education (adjusted relative risk [aRR], 1.32; 95% CI, 0.99-1.76; non–statistically significant finding), who spoke an Indigenous language at home (aRR, 1.30; 95% CI, 0.97-1.73; non–statistically significant finding), who worked in the fields (aRR, 1.60; 95% CI, 1.03-2.50), and who were exposed to a known or suspected COVID-19 case at home (aRR, 2.98; 95% CI, 2.06-4.32) or in the workplace (aRR, 1.59; 95% CI, 1.18-2.14). Positive results on IgG tests for SARS-CoV-2 infection were more common among those who lived in crowded housing (aRR, 1.23; 95% CI, 0.98-1.53; non–statistically significant finding), with children aged 5 years or younger (aRR, 1.40; 95% CI, 1.11-1.76), with unrelated roommates (aRR, 1.40; 95% CI, 1.19-1.64), and with an individual with known or suspected COVID-19 (aRR, 1.59; 95% CI, 1.13-2.24). The risk of IgG positivity was also higher among those with body mass index of 30 or greater (aRR, 1.65; 95% CI, 1.01-2.70) or diabetes (aRR, 1.31; 95% CI, 0.98-1.75; non–statistically significant finding). Conclusions and Relevance In this cross-sectional study of farmworkers in California, both residential and workplace exposures were associated with SARS-CoV-2 infection. Urgent distribution of COVID-19 vaccines and intervention on modifiable risk factors are warranted given this population’s increased risk of infection and the essential nature of their work.

To evaluate the effects of lactylate and Bacillus subtilis on growth performance, complete blood cell count, and microbial changes, 264 weaning pigs were assigned to 4 treatments (1) control (Con) basal diets that met the nutrient requirement for each phase, (2) 0.2% lactylate (LA), (3) 0.05% Bacillus subtilis strains mixtures (BM) providing 2 x 105 CFU/g of complete feed, or (4) the combination of LA and BM (LA+BM) added to the control basal diet at their respective inclusion rates in each of the 3 phases. Dietary lactylate tended to increase weight gain, significantly increased feed intake, and reduced fecal total E. coli and enterotoxigenic E. coli counts during Phase 1. Pigs fed Bacillus subtilis had a greater gain to feed ratio (G:F) during Phases 1 and 2. Pigs fed lactylate had an increased peripheral absolute neutrophil count on D14 but a decreased eosinophil percentage. Pigs fed Bacillus subtilis had an elevated peripheral total white blood cell count at study completion. The addition of lactylate increased microbiota richness, reduced E. coli, and increased Prevotella, Christensenellaceae, and Succinivibrio. Bacillus subtilis supplementation-enriched f_Ruminococcaceae_unclassified and S24-7_ unclassified had positive relationships with feed efficiency. Collectively, these findings suggested that lactylate can be added to diets to balance gut microbiota and improve growth performance during the early postweaning period. The combination of lactylate and Bacillus subtilis strains exerted a synergic effect on the growth performance of nursery pigs.

Cognitive Processing Therapy (CPT) is efficacious in treating PTSD, but there remains a need to improve outcomes for individuals who do not fully respond to treatment. Differences between patient-therapist dyads in the fidelity (i.e., adherence and competence) of CPT delivery and the quality of the therapeutic relationship may partly explain differential levels of symptom improvement. Sessions were sampled from a randomized trial comparing different consultation conditions in training therapists new to CPT. Among 69 patients, one session from Sessions 1-3 and one session from Sessions 4-7 were reliably rated for adherence and competence using the CPT Therapist Adherence and Competence Scale, and for therapeutic alliance using the Working Alliance Inventory-Observer scale. Mixed models, including detrending using a fixed effect of session, predicted self-reported Posttraumatic Stress Disorder Checklist (PCL-IV) scores in one session using process scores from the previous session. The statistical interaction between fidelity and alliance scores to predict outcome was also examined. Alliance had significant, positive correlations (rs = 0.18-0.21) with same-session adherence and competence. Higher competence scores and higher therapeutic alliance scores in one session were independently associated with lower PCL-IV scores in the subsequent session. Adherence scores, which tended to be very high with relatively less variability, did not significantly relate to subsequent-session PCL-IV scores. Competence significantly interacted with alliance, such that sessions high in both competence and alliance predicted especially lower subsequent-session PCL-IV scores. A strong therapeutic alliance may have a synergistic, salutary effect with the competent delivery of CPT.

To evaluate the effects of lactylate and Bacillus subtilis on growth performance, complete blood cell count, and microbial changes, 264 weaning pigs were assigned to four treatments (1) control (Con) basal diets that met the nutrient requirement for each phase, (2) 0.2% lactylate (LA), (3) 0.05% Bacillus subtilis strains mixtures (BM), or (4) the combination of LA and BM (LA+BM) added to the control basal diet at their respective inclusion rates in each of the three phases. Dietary lactylate tended to increase weight gain, significantly increased feed intake, and reduced fecal total E. coli and enterotoxigenic E. coli counts during Phase 1. Pigs fed Bacillus subtilis had a greater gain to feed ratio (G:F) during Phases 1 and 2. Pigs fed lactylate had an increased peripheral absolute neutrophil count on D14 but a decreased eosinophil percentage. Pigs fed Bacillus subtilis had an elevated peripheral total white blood cell count at study completion. The addition of lactylate increased microbiota richness, reduced E. coli, and increased Prevotella, Christensenellaceae, and Succinivibrio. Bacillus subtilis supplementation-enriched f_Ruminococcaceae_unclassified and S24-7_ unclassified had positive relationships with feed efficiency. Collectively, these findings suggested that lactylate can be added to diets to balance gut microbiota and improve growth performance during the early postweaning period. The combination of lactylate and Bacillus subtilis strains exerted a synergic effect on the growth performance of nursery pigs.

ImportanceEssential workers in agriculture and food production have been severely affected by the ongoing COVID-19 pandemic.ObjectiveTo identify risk factors associated with SARS-CoV-2 shedding and antibody response in farmworkers in California.DesignThis cross-sectional study collected survey data and determined current SARS-CoV-2 shedding and seropositivity among 1,107 farmworkers in California’s Salinas Valley from 16 July to 30 November 2020.SettingFarmworkers receiving transcription-mediated amplification (TMA) tests for SARS-CoV-2 infection at federally qualified community clinics and community sites were invited to participate in our study.ParticipantsIndividuals were eligible if they were not pregnant, ≥18 years old, had conducted farm work since the pandemic started, and were proficient in English or Spanish.ExposuresSociodemographic, household, community, and workplace characteristics.Main Outcome(s) and Measure(s)Current (as indicated by TMA positivity) and historical (as indicated by IgG seropositivity) SARS-CoV-2 infection.ResultsMost farmworkers enrolled in the study were born in Mexico, had primary school or lower levels of educational attainment, and were overweight or obese. Current SARS-CoV-2 shedding was associated in multivariable analyses with attained only primary or lower educational levels (RR=1.32; 95% CI: 0.99-1.76), speaking an indigenous language at home (RR=1.30; 0.97-1.73), working in the fields (RR=1.60; 1.03-2.50), and exposure to known or suspected COVID-19 case at home (RR=2.98; 2.06-4.32) or in the workplace (RR=1.59; 1.18-2.14). Antibody detection was associated with residential exposures including living in crowded housing (RR=1.23; 0.98-1.53), with children (RR=1.40; 1.1-1.76) or unrelated roommates (RR=1.40; 1.19-1.64), and with a known or suspected COVID-19 case (RR=1.59; 1.13-2.24). Those who were obese (RR=1.65; 1.01-2.70) or diabetic (RR=1.31; 0.98-1.75) were also more likely to be seropositive. Farmworkers who lived in rural areas other than Greenfield (RR=0.58; 0.47-0.71), worked indoors (RR=0.68; 0.61-0.77), or whose employer provided them with information on how to protect themselves at work (RR=0.59; 0.40-0.86) had lower risk of prior infection.Conclusions and RelevanceOur findings suggest both residential and workplace exposures are contributing to SARS-CoV-2 infection among farmworkers in California. Urgent distribution of COVID-19 vaccines is warranted given this population’s increased risk of infection and the essential nature of their work.

As essential personnel, United States farmworkers have continued working in-person throughout the COVID-19 pandemic. We undertook prospective surveillance of SARS-CoV-2 infection and antibody prevalence among farmworkers in California’s Salinas Valley from 15 June to 30 November, 2020. Over this period, we observed 22.1% (1514/6864) positivity for current SARS-CoV-2 by nucleic acid detection among farmworkers tested at federally-qualified migrant and community health clinics, as compared to 17.2% (1255/7305) among other adults from the same communities (risk ratio, 1.29; 95% confidence interval, 1.20-1.37). In a nested study enrolling 1,115 farmworkers, prevalence of current infection was 27.7% among farmworkers reporting ≥1 potential COVID-19 symptom, and 7.2% among farmworkers without symptoms (adjusted odds ratio 4.17; 2.86-6.09). Prevalence of anti-SARS-CoV-2 IgG antibodies increased from 10.5% (6.0-18.4%) between 16 July-31 August to 21.2% (16.6-27.4%) between 1-30 November. The high observed prevalence of infection among farmworkers underscores the need for vaccination and other preventive interventions.

Background: Chronic Obstructive Pulmonary Disease (COPD) and Heart Failure are an important cause of morbidity and mortality around the world. The decrease of oxygen tissue produces an increment in the oxidative distress, peroxides, and free radicals inducing body composition alterations, specifically phase angle (PA) which is an integrity indicator of membrane cellular and a prognosis factor. However, no studies evaluating the relation between hypoxia and PA in COPD and HF patients has been reported. Objective: To determinate association between hypoxia and PA in COPD and HF patients. Methods: Cross sectional study, 159 subjects were evaluated. Subjects older than 40 years old, COPD and HF diagnosis were included. Asthma and cancer subjects were excluded. Body composition and PA were assessed by bioelectrical impedance vectorial analysis (RJL Systems. Quantum IV). Hypoxia was defined by oxygen saturation Results: The mean age was 67.4 ± 12, 58.1 % were woman and 61.83 % had cachexia. Hypoxia subjects had less PA (4.3 ± 0.84 vs 4.94 ± 0.93, p = 0.046), as well major edema (89.89 % vs 58.8 %, p =0.203) than without hypoxia subjects. No showed statistical significance between the groups in grip strength, impedance index, and skeletal muscle mass. Conclusion: In COPD and HF subjects, the hypoxia represents an important negative impact in body composition, especially on membrane cellular integrity Key words: Chronic Obstructive Pulmonary Disease, Heart Failure, Membrane Cellular integrity, Phase angle, body composition

Heart Failure (HF) patients developed changes in body composition as overhydration, muscle-skeletal wear and cardiac cachexia (CC). The possible factors involved in the development of CC in Right Heart Failure (RHF) patients are venous congestion, nutrient malabsorption. However, in HF, the overhydration obscure the loss of fat-free mass and difficult the body composition assessment. Bioelectrical impedance vectorial analysis (BIVA) is a method validated and used for hydration status and body composition assessment in HF. The aim of this study was to investigate the body compositions changes assessment by BIVA in the subjects with and without RHF and evaluate the risk factors for devolvement CC in HF subjects.Prospective cohort study. Subjects with confirmed diagnoses of HF,18 years old without CC according to BIVA criteria were included. Subjects with congenital heart disease, cancer, HIV, and end-stage renal disease were excluded. Body composition was an assessment by BIVA. 288 HF patients were evaluated. RHF subjects had an impedance vector reduction (9.26 dR/H and -1.92 dXc/H, T2=14.9, D = 0.45, p0.001), while subjects without RHF no-showed statistically significant changes (7.57 dR/H and 0.72 dXc/H, T2=3, D = 0.17, p = 0.200). The risks factors to development CC were age, RHF, phase angle5°, total body water were risks factors while handgrip strength was a protector factor.RHF has greater disturbances in body composition and is a risk factor to development CC.

One of most negative campaigns in history may have taken place during the 2014 Senate election cycle. Nearly 75% of senate ads aired during a two-week period in early fall of 2014 showed a candidate in a negative light, according to the Wesleyan Media Project. A postelection analysis by the Center for Public Integrity showed that 46% of the more than one million ads aired during the 2014 senate campaigns were negative. And, in the most competitive states, the proportion of negative ads was even higher (e.g., 67% in North Carolina, 58% in Kansas). Negative advertisements sponsored by candidates, interest groups, and political parties are being launched on the airways, in newspapers, on radio, and via the Internet at an unprecedented pace. These advertisements, however, are now routinely subjected to fact checking.The Washington Post, along with many other fact-checking organizations, such as PolitiFact, The AP Factcheck, and Factcheck.org, examine thousands of statements and political advertisements during campaigns to determine the accuracy of the claims. For instance, during the 2012 election cycle, PolitiFact had 36 reporters and editors working in 11 states producing more than 800 fact checks on the presidential campaign and hundreds more for candidates running for the U.S. House and U.S. Senate.

Actualmente se promueve una enseñanza donde el docente favorezca la interacción con los (as) alumnos (as) y la comprensión de los contenidos temáticos a través de experiencias de aprendizaje significativas. A pesar de ello, en México aún se observa la necesidad de capacitación a docentes en servicio, de manera que se les proporcionen estrategias acordes a los requerimientos educativos. Por tal razón el “taller para el manejo de competencias didácticas en docentes de nivel preescolar”, se planteó como herramienta de apoyo en el trabajo docente, realizándose en una institución pública, en la colonia Antonio Barona, en Cuernavaca Morelos. El estudio fue cualitativo, con diseño de investigación-acción y una muestra no probabilística por conveniencia de cinco docentes. El objetivo buscó valorar la propuesta de intervención, para favorecer el manejo de competencias didácticas en los docentes de nivel preescolar. En la recolección de datos se utilizó la técnica de observación, entrevista semiestructurada y el cuestionario “DEMEVI de estilos de enseñanza para docentes de nivel preescolar”, adaptación de Henao y Molina (2013), e instrumentos como fichas de observación, registro anecdótico y fotografías. Los resultados reflejan disposición de las docentes para reorientar la práctica, un diseño de actividades con mayor contenido didáctico, recursos pedagógicos variados y el diseño de situaciones de aprendizaje de acuerdo a las necesidades de los alumnos. Concluyendo que es preciso una formación continua y factible, de manera que les brinde las herramientas pedagógicas necesarias para reorientar la práctica de acuerdo a los requerimientos de la sociedad actual.

[Abstract:] In the wind engineering field, the so-called D-section (semi-circular cylinder) has attracted some attention from researchers, since it is a galloping prone geometry. In fact, a modest number of references where this type of cross-section has been studied in the wind tunnel can be found, such as Novak and Tanaka (1974) or Weaver and Veljkovic (2005). However, to the authors’ knowledge, references in the literature concerning the CFD-based simulation of the aerodynamic response of circular segments are particularly scarce. In this work a 2D Unsteady Reynolds-Averaged Navier–Stokes (URANS) approach has been adopted with the purpose of computing force coefficients and Strouhal numbers of static circular segments at the subcritical regime considering corner angles of 90, 80, 70, 60, 50 and 40. Since the motivation of this work is to study circular segments as a simplified bridge deck geometry, the reference flow direction is parallel to the rectilinear side. It has been found that this kind of cross-section is particularly challenging since it presents massive flow separation on the rectilinear side, as well as the inherent difficulties in modeling the aerodynamic response on curved surfaces at high Reynolds numbers. For certain geometrical configurations low-Reynolds-number and curvature corrections in the k − ω Shear-Stress Transport (SST) turbulence model had to be introduced, as well as considering transition from laminar to turbulent flow, in order to obtain results similar to the experimental data. Ministerio de Economía y Competitividad; BIA2013-41965-P