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COVID-19-related alcohol sales bans and stay-at-home orders prompted the alcohol industry in South Africa to increase their online alcohol sales promotions. We investigated changes in alcohol-related behaviour and the drivers of illegal alcohol sales through a self-reported Facebook survey that ran from July to November 2020. Questions included socio-demographics and comparison of alcohol purchasing behaviour and intake during 2019 and 2020. Statistical tests were applied to find associations between illegal alcohol purchasing and alcohol-related behaviours. A total of 792 participants took part in the survey, 69.7% of whom were female. During lockdown periods, most participants (55.3%) bought alcohol illegally from illegal outlets or friends. Online alcohol-delivery marketing increased by 20 percentage points from 2019 to 2020, with participants stating that they saw a lot of advertisements per day and 80% of persons under 25 years were not asked to verify their age in 2020 upon delivery. Home-brewed beer and vodka intake increased in 2020 during the alcohol sales bans. Men from the Western Cape who engaged in daily or weekly heavy episodic drinking were more prone to purchase alcohol illegally. The Western Cape, which is South Africa's most prolific wine-producing region, had the highest odds of people buying alcohol illegally, with wine being found to be the most frequently bought alcohol online and consumed by these participants. There is a need for further research into the differences in alcohol-related behaviour affecting illegal alcohol purchasing according to income group, proximity to alcohol producers and underage alcohol sales and marketing through online applications. SIGNIFICANCE: • Alcohol sales bans have the potential to reduce and stop the alcohol intake of moderate drinkers, but may make heavy episodic drinkers drink more than usual. • During COVID-19 lockdown, illegal alcohol sales were taking place through unlicenced alcohol outlets and friends, and not through licenced online applications. • Unlicenced alcohol outlets need to be addressed to prevent future illegal alcohol sales. • Stricter regulations aimed at legal online alcohol sales applications should be put in place to prevent alcohol sales to minors and those who have already consumed too much alcohol. • There should be a ban on marketing of addictive substances, such as alcohol.

https://doi.org/10.17159/sajs.2023/14543

Cognitive coping strategies that supported teacher resilience during the COVID-19 pandemic
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Williams, Elisma

; Ferreira, Ronél

; Botha, Tanita

South African Journal of Education

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Dic 2023, Volumen 43 Supl. 1 Paginas s1 - s16

Resumen: En | Texto: En | PDF: En

Limited research focusing on the cognitive strategies that support the resilience of teachers in a world pandemic has been conducted. By employing a sequential explanatory mixed method research design, this study was undertaken to investigate how cognitive coping strategies supported teacher resilience during the COVID-19 pandemic. For data collection/generation and capturing/documentation, an online questionnaire (Phase 1, quantitative) was completed by 240 urban school teachers, and online participatory focus groups (Phase 2, qualitative) with 24 of these respondents were facilitated. In support, observation, audio-recordings, field notes and a reflective journal augmented data generation. Descriptive and inferential statistics were used for analysis of the quantitative data, and a hybrid thematic analysis approach was followed to analyse the qualitative data. Thereafter, the quantitative and qualitative results were integrated to achieve the purpose of the study. The results from analyses included the Spearman correlation coefficient which tested a value of 0.327 (p-value = < 0.001), indicating a significant and positive correlation between problem-focused coping and resilience. Cognitive strategies indicated to support resilience included active coping, planning, suppression of competing activities, restraint coping, seeking of instrumental social support and nurturing a growth mindset. The cognitive strategies identified in this study informs good practice principles and can direct the professional training of both psychologists and educators. Future research and interventions aimed at promoting teacher resilience by employing cognitive coping strategies may be conducted based on the findings of the study.

https://doi.org/10.15700/saje.v43ns1a2425

Detección radiográfica oportuna de displasia del desarrollo de la cadera en residentes de medicina familiar. Intervención educativa
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Gaytán-Fernández, Suemmy

; Barragán-Hervella, Rodolfo G.

; Quiroz-Williams, Jorge

; Valle-Cortés, Evelyn M. Del

; Castillo-Ramírez, Isabel O.

; Montiel-Jarquín, Álvaro J.

Cirugía y cirujanos

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Oct 2023, Volumen 91 Nº 5 Paginas 703 - 708

Resumen: Es En | Texto: Es En | PDF: Es | PDF: En

Resumen Antecedentes: La displasia del desarrollo de la cadera (DDC) constituye una entidad clínica compleja que suele ser infradiagnosticada que, de no ser precozmente detectadas y manejadas, convertirán al individuo afectado en un ser discapacitado, con efecto negativo social, económico y emocional. Objetivo: Determinar la capacidad para la detección radiográfica oportuna de la DDC antes y después de una intervención educativa en médicos residentes de medicina familiar. Método: Se realizó una intervención educativa en residentes de medicina familiar, en la que se les dio capacitación sobre detección de DDC en proyecciones radiográficas. Se realizó una evaluación previa y posterior a la capacitación. El análisis estadístico se realizó mediante pruebas t de Student y χ2, tomando como significativo un valor de p ≤ 0.05. Resultados: Participaron 94 residentes. El 87.2% dijeron no conocer el protocolo radiológico de detección. En la evaluación preintervención, el 87.2% no tenían conocimiento del protocolo (p = 0.525). Se observó que el 98.9% trazaron de manera incorrecta la línea de Perkins (p = 0.427), el 96.8% la línea de Hilgenreiner (p = 0.177) y el 87.2% no consideraron los datos de displasia bilateral (p = 0.956). Posterior a la intervención educativa, el 87.2% trazaron de manera correcta la línea de Perkins (p = 0.926), el 97.8% la línea de Hilgenreiner (p = 0.325) y el 78.7% sí consideró los datos de displasia bilateral (p = 0.826). Conclusiones: Tras la capacitación, el 80% de los médicos residentes de medicina familiar fueron capaces de detectar oportunamente la DDC.

Abstract Background: Developmental dysplasia of the hip (DDH) is a complex clinical entity that is usually underdiagnosed, if not detected and managed early, will turn the affected individual into a disabled being, with negative social, economic and emotional effects. Objective: To determine the capacity for the timely radiographic detection of DDH before and after an educational intervention. Method: An educational intervention is carried out in family medicine resident, where they are given training on detection in DDH radiographic projections. Pre- and post-training evaluation is carried out. Statistical analysis is performed using Student's t and χ2, taking p ≤ 0.05 as significant. Results: 94 residents participated. In the pre-intervention evaluation, 87.2% had no knowledge of the early detection protocol (p = 0.525). It was observed that 98.9% incorrectly drew the Perkins line (p = 0.427), 96.8% the Hilgenreiner line (p = 0.177) and 87.2% did not consider the data of bilateral dysplasia (p = 0.956). After the educational intervention, 87.2% correctly drew the Perkins line (p = 0.926), 97.8% the Hilgenreiner line (p = 0.325) and 78.7% if they considered the data of bilateral dysplasia (p = 0.826). Conclusions: After this training, 80% of family medicine residents were able to detect DDH in a timely manner.

https://doi.org/10.24875/ciru.21000797

Occupational therapists' acceptance of 3D printing
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Barter, Shelley Louise

; Williams, Alexandra Jean

; Rencken, Gina

; Ndaba, Nonjabulo

; Govender, Pragashnie

South African Journal of Occupational Therapy

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Ago 2023, Volumen 53 Nº 2 Paginas 3 - 17

Resumen: En | Texto: En | PDF: En

INTRODUCTION: In occupational therapy, three-dimensional printing is being explored as an alternative design and manufacturing technique to the conventional fabrication of orthotics and assistive devices. The global applications and literature are rapidly growing, but the South African - specific literature is deficient. The Technology Acceptance Model depicts that one's perception of any particular technology is a significant determinant of their acceptance of it, determining whether the technology system is successfully adopted or disregarded AIM: To determine the perceived acceptance of three-dimensional printing technology amongst occupational therapists in KwaZulu-Natal and whether exposure to the technology system, in the form of a three-dimensional printing workshop, influences their perception of the technology METHOD: The study followed a multi-method design consisting of two phases; phase one involved the creation of the intervention tool (workshop), which was developed through a process guided by Design-Based Research. Phase two involved the implementation of the intervention and data collection. Therapists documented their perceptions in a questionnaire before and after exposure; following a pre and post-test design, enabling comparison. The questionnaires were based on the Technology Acceptance Model, including 13 questions scored on a seven-point Likert scale and five open-ended questions. The quantitative data were analysed descriptively, and qualitative data were analysed thematically RESULTS: All four categories of the Technology Acceptance Model-based questionnaire displayed a significant change (p < 0.05) between the pre and post-test responses, with a medium effect size CONCLUSION: Exposure to three-dimensional printing influences therapists' perception of the technology IMPLICATIONS FOR PRACTICE • The application of Three-Dimensional Printing (3DP) in occupational therapy practice has the potential to enable increased accuracy and precision of items fabricated by therapists; enabling customisation and individualisation to the exact specifications of a patient. • 3DP can open doors to a broad spectrum of items that are not easily accessible, affordable, or not even available, accessing ideas and blueprints from a global pool of resources through open-source sites. • With the process of fabrication being digital, not only does this reduce manual labour, but fabricating without touching the patient can reduce pain and prevent disruption of a repair/ surgical site/ wound. • The digital process also allows patients to see and visualise the product during the design process, enabling input prior to printing, contributing to reduced wastage.

https://doi.org/10.17159/2310-3833/2023/vol53n2a2

Could a one-size-fits-all approach apply to the extension of stage-discharge relationships at flow-gauging weirs?
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Gericke, O J

; Williams, V H

Journal of the South African Institution of Civil Engineering

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Jun 2023, Volumen 65 Nº 2 Paginas 17 - 27

Resumen: En | Texto: En | PDF: En

At a flow-gauging weir, the stage or flow depth is normally measured continuously and converted into discharge using a stage-discharge (SD) rating curve (RC). During flood events, the observed water levels often exceed the flow-gauging weir's designed measuring capacity or structural limit. Subsequently, the standard calibration of the flow-gauging weir becomes irrelevant and the extension of the SD RC for above-structure-limit flow conditions is required. This paper attempts to identify a one-size-fits-all approach for the extension of SD RCs by assessing seven indirect hydraulic extension methods and a one-dimensional HEC-RAS modelling approach against direct SD measurements or extension methods at selected flow-gauging sites in South Africa. In considering a ranking-based selection procedure and associated goodness-of-fit (GOF) criteria, the stepped backwater analysis, slope-area method, and 1-D HEC-RAS steady flow modelling proved to be the most appropriate. The other indirect extension methods resulted in larger statistical differences between the at-site benchmark and modelled values. Given that the extension of RCs is significantly more affected by the site and river reach geometry, initial hydraulic conditions, flow regimes, and level of submergence at high discharges than the actual extension method used, it was confirmed that a one-size-fits-all approach cannot be applied for the extension of SD RCs in South Africa.

https://doi.org/10.17159/2309-8775/2023/v65n2a3

Epithelial responses and Candida albicans pathogenicity are enhanced in the presence of oral streptococci
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Martorano-Fernandes, Loyse

; Brito, Arella Cristina Muniz

; Araújo, Elza Cristina Farias de

; Almeida, Leopoldina de Fátima Dantas de

; Wei, Xiao-Qing

; Williams, David Wynne

; Cavalcanti, Yuri Wanderley

Brazilian Dental Journal

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Jun 2023, Volumen 34 Nº 3 Paginas 73 - 81

Resumen: En Pt | Texto: En Pt | PDF: En | PDF: Pt

Abstract Experimental models that consider host-pathogen interactions are relevant for improving knowledge about oral candidiasis. The aim of this study was to assess the epithelial immune responses, Candida penetration of cell monolayers, and virulence during mixed species culture infections. Single species cultures of Candida albicans and mixed cultures (C. albicans, Streptococcus mutans, and Streptococcus sanguinis) were used to infect monolayers of HaCaT and FaDu ATCC HTB-43 cells for 12 h. After infection, IL-18 and IL-34 gene expression was measured to assess epithelial cell immune responses, and lactate dehydrogenase (LDH) activity was measured as an indicator of cell damage. Microscopy determined C. albicans morphology and penetration of fungal cells through the keratinocyte monolayer. Monolayers devoid of infection served as controls. Data were analyzed by an ANOVA one-way test followed by Tukey’s post-hoc test (α = 0.05). The results found that IL-18 and IL-34 gene expression and LDH activity were significantly (p < 0.05) upregulated for both cell lines exposed to mixed species cultures compared with C. albicans alone. Candida albicans yeast and hyphae were evident in C. albicans only infections. In contrast, monolayers infected by C. albicans, S. mutans, and S. sanguinis exhibited higher microbial invasion with several hyphal aggregates detected. The presence of streptococci in C. albicans infection enhances the virulence and pathogenicity of the fungus with associated increased immune responses and tissue damage. Extrapolation of these findings to oral infection would indicate the added potential benefit of managing bacterial components of biofilms during treatment.

Resumo O objetivo deste estudo foi avaliar a resposta epithelial imune, a colonização da Candida albicans em monocamadas celulares e sua virulência em resposta a infecções de culturas de biofilme multiespécie. Culturas de biofilme monoespécie de C. albicans e culturas mistas (C. albicans, Streptococcus mutans e Streptococcus sanguinis) foram utilizadas para infectar monocamadas de células HaCaT e FaDu por 12 h. Após a infecção, a expressão dos genes IL-18 e IL-34 foi medida para avaliar as respostas imunes das células epiteliais. A atividade da lactato desidrogenase (LDH) foi medida como um indicador de dano celular. A microscopia determinou a morfologia de C. albicans e a penetração das células fúngicas através da monocamada de queratinócitos. Monocamadas em que não houve infecção serviram como controles. Os dados foram analisados por um teste ANOVA one-way seguido pelo teste post-hoc de Tukey (α = 0,05). Os resultados demonstraram que a expressão gênica de IL-18 e IL-34 e a atividade de LDH foram (p < 0,05) reguladas positivamente para ambas as linhagens de células expostas a culturas de espécies mistas em comparação com C. albicans isoladamente. Leveduras de C.albicans e hifas foram evidentes em infecções apenas por C. albicans. Entretanto, monocamadas infectadas por C. albicans, S. mutans e S. sanguinis exibiram maior invasão microbiana com vários agregados de hifas detectados. Dessa maneira, a presença de estreptococos na infecção por C. albicans aumentou a virulência e a patogenicidade do fungo com respostas imunes aumentadas associadas a danos nos tecidos. A extrapolação desses achados para a infecção oral indicaria o potencial benéfico do controle dos componentes bacterianos em biofilmes durante a terapia da candidíase

https://doi.org/10.1590/0103-6440202305420

The biochemical, microbiological and histological findings in native joint septic arthritis in adults
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Maimin, Dane

; Martin, Vijay

; Williams, Kaylin

; Dey, Roopam

; Dlamini, Sipho

; Maqungo, Sithombo

SA Orthopaedic Journal

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2023, Volumen 22 Nº 4 Paginas 204 - 207

Resumen: En | Texto: En | PDF: En

BACKGROUND: Septic arthritis is an orthopaedic emergency with an incidence of 2 to 10 per 100 000 patients in the general population. Mortality rates between 3 and 29% can be expected. Local knowledge of microorganisms and antibiotic sensitivities will facilitate expedited and effective treatment. The aim of the study was to review and analyse the microbiological, histological and biochemical findings in patients taken to theatre for the purposes of treating a septic arthritis of native joints in adult patients at our institution. METHODS: A retrospective case series analysis was performed. We included only adult patients that were taken to theatre for treatment of a presumed septic joint. We excluded paediatric patients, joints distal to the elbow or ankle, and the spine. Preoperative blood tests and samples obtained intraoperatively for microbiological and histological testing were analysed. Inflammatory markers were compared against culture results. Bacteria trends and antibiotic sensitivities were assessed. Histological findings were analysed against positive cultures. RESULTS: In our study, 104 patients were taken to theatre for the treatment of presumed septic arthritis during the data collection period. Eighty-six (81%) were found to have septic arthritis based on cultures and/or histology. The knee was the most affected joint (67%). A regression analysis suggested that high erythrocyte sedimentation rate and high C-reactive protein levels were better predictors for septic arthritis compared to white cell count. Methicillin-sensitive Staphylococcus aureus (31%), Staphylococcus epidermidis (10%) and Enterobacter cloacae complex (8%) were the most common organisms identified. Multidrug-resistant organisms were cultured in 19% (9/48) cases, in the form of methicillin-resistant Staphylococcus aureus, Proteus mirabilis and Acinetobacter baumannii. CONCLUSION: Septic arthritis remains a diagnostic challenge and organism and antibiotic patterns vary. We present a review and summary of all septic joints over a seven-year period at a tertiary level orthopaedic service. Level of evidence: Level 4

https://doi.org/10.17159/2309-8309/2023/v22n4a6

Continuous glucose monitoring empowers adolescents to take responsibility of diabetes management
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Williams, Letitia

; Deacon, Elmarí

; Van Rensburg, Esmé

; Segal, David

African Journal of Primary Health Care & Family Medicine

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2023, Volumen 15 Nº 1 Paginas 1 - 6

Resumen: En | Texto: En | PDF: En

BACKGROUND: Managing diabetes is especially challenging for adolescents, and they often struggle to believe they can manage the condition. Illness perception has been widely associated with better diabetes management outcomes, but the influence of continuous glucose monitoring (CGM) on adolescents has been largely neglected. AIM: The study aimed to explore the illness perception of a group of adolescents living with type 1 diabetes (T1D) using CGM. SETTING: The study was conducted at a medical centre that provides diabetes care services to youth living with T1D in Parktown, South Africa. METHODS: A qualitative research approach using semi-structured online interviews was used to gather data that was thematically analysed. RESULTS: Themes emerging from the data confirmed that CGM creates a sense of control over diabetes management as blood glucose measures were more visible. A sense of normalcy was established as CGM influences a new routine and a way of life, integrating diabetes into a young person's identity. Despite the users' awareness of being different due to diabetes management, CGM assisted in creating a sense of belonging, contributing to developing a better quality of life. CONCLUSION: Findings of this study support the use of CGM as a means of empowering adolescents struggling with diabetes management to achieve better treatment outcomes. The important role of illness perception in facilitating this change was also evident. CONTRIBUTION: By listening to the adolescent's voice, CGM was identified as a possible intervention to empower adolescents to improve diabetes management.

https://doi.org/10.4102/phcfm.v15i1.3879

Variabilidad transversal de características dimensionales de traqueidas en Pinus caribaea var. hondurensis de plantaciones de 25 años de edad
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Márquez-Carrero, Gabrialy

; Valero, Styles W.

; León-Hernández, Williams J.

; Gutiérrez-Gotera, Ilvania J.

; Maldonado-Rangel, Julio C.

Revista Tecnología en Marcha

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Sep 2022, Volumen 35 Nº 3 Paginas 82 - 93

Resumen: Es En | Texto: Es En | PDF: Es | PDF: En

Resumen Se presenta el estudio de variabilidad de longitud, diámetro total, diámetro del lumen, espesor de pared y fracción de pared de las traqueidas de Pinus caribaea var. hondurensis proveniente de plantaciones de 25 años de edad establecidas en Uverito (estado Monagas,Venezuela). Se examinaron un total de seis individuos y se preparó tejido macerado en tres posiciones de la sección transversal: adyacencias de médula, punto medio (muestras en madera temprana y madera tardía) y adyacencias del cambium. Los resultados indican que el mayor diámetro promedio (total y del lumen) correspondió a la madera temprana, mientras que los mayores grosores y fracción de pared se concentraron hacia la madera tardía. En relación a la longitud de traqueidas aumenta desde la zona cercana a la médula hasta el punto medio de la sección transversal para, posteriormente, disminuir hacia las adyacencias del cambium y alcanzar valores muy similares a los del punto inicial. El patrón de variación de longitud de traqueidas indica que a partir del punto medio de la sección transversal comienza la formación de madura adulta.

Abstract This research is about variability of quantitative features (length, diameter, thickness, wall fraction) in tracheids of Pinus caribaea var. hondurensis from 25 years old plantations from Uverito (Monagas state, Venezuela). Six trees were studied and macerated tissue were prepared in three positions in cross section: near of pith, middle point of cross section and near of cambium. Higher diameter was observed in early wood and in late wood were found higher thickness wall. Tracheid length had an increment from the pith to middle point and, then, showed a reduction from middle point to cambium. According variation in tracheids length, adult wood appears from the middle point to cambium

https://doi.org/10.18845/tm.v35i3.5868

10.

Presencia de síntomas de ansiedad y depresión en estudiantes de medicina durante la pandemia de COVID-19
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Villalón López, Francisco J.

; Moreno Cerda, María Ivonne

; GonzáLez Venegas, Williams

; Soto Amaro, Adrián Alonso

; Arancibia Campos, Javiera Valentina

Revista médica de Chile

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Ago 2022, Volumen 150 Nº 8 Paginas 1018 - 1025

Resumen: Es En | Texto: Es En | PDF: Es | PDF: En

Background: Medical students are especially prone to anxiety and depression. Aim: To characterize the presence of anxiety and depression and their association with gender and academic year among medical students. Material and Methods: Standardized electronic surveys about anxiety and depression symptoms were sent to 498 medical students with a response rate of 78%. Results: We analyzed 359 surveys. A mean of 11.4 points out of 27 was observed in the depression symptoms scale. Also, 23 and 10% of respondents had moderately severe or symptoms of depression, respectively. A mean of 8.9 out of 21 points in the anxiety symptoms scale was observed. Moderate or severe anxiety symptoms were present in 26 and 15% of respondents, respectively. Women and preclinical students had higher depression and anxiety scores. Conclusions: A high presence of anxiety and depression symptoms was characterized among medical students during the pandemic. Preclinical students and women had higher scores in both scales.

11.

Secado de Pinus caribaea var. hondurensis utilizando radiación de microondas
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Luckert Froget, Simón E.

; Benítez Díaz, Pedro R.

; Valero, Styles W.

; León Hernández, Williams J.

; Gutiérrez Gotera, Ilvania

Revista Tecnología en Marcha

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Jun 2022, Volumen 35 Nº 2 Paginas 61 - 75

Resumen: Es En | Texto: Es En | PDF: Es | PDF: En

Resumen Se desarrolló una metodología de secado para Pinus caribaea var. hondurensis, empleando horno de microondas doméstico (HMO), consistente de pulsos de radiación y períodos de enfriamiento, que consume 92% menos energía y 58% menos tiempo. Las propiedades físicas y mecánicas se midieron en condición seca al HMO, equilibrio higroscópico (EH) y secado convencional, ρverde: 1049 ± 74 kg/m3 (CH: 107 ± 18 %), ρsecaHMO: 555 ± 63 kg/m3 , ρEH: 565 ± 51 kg/ m3 (CH: 11,3 ± 0,8 %), Vverde: 58 ± 1 x10-6 m3 y VHMO: 51 ± 26 x 10-6 m3 y contracción volumétrica: 11 ± 3 %, no presentando diferencias significativas con respecto al secado convencional. Los valores de la compresión paralela al grano fueron: ELPHMO: 6 ± 2 x 106 kg/m2 , MRHMO: 6 ± 2 x 106 kg/m2 y MOEHMO: 4 ± 1 x 108 kg/m2 , ELPEH: 3,0 ± 0,5 kg/m2 , MREH: 3,5 ± 0,64 kg/m2 y MOEEH: 2,3 ± 0,6 kg/m2 ; tampoco mostraron diferencias con respecto al secado convencional. La única alteración anatómica observada fue un aumento de agrietamientos espiralados en las paredes de las traqueidas y no parece tener repercusión sobre las propiedades evaluadas. Se concluyó que la exposición al microondas no altera las propiedades estudiadas siendo un método confiable de secado.

Abstract A methodology was developed for drying Pinus caribaea var. hondurensis, using a domestic microwave oven (HMO) consisting of radiation pulses and cooling periods and consumes 92% less energy and 58% less time. The physical and mechanical properties were measured in the dry condition of HMO, hygroscopic equilibrium (HE) and conventional drying, ρgreen : 1049 ± 74 kg/m3 (CH: 107 ± 18%), ρdryHMO: 555 ± 63 kg/m3 , ρEH : 565 ± 51 kg/m3 (CH: 11.3 ± 0.8%), Vgreen : 58 ± 1 x 10-6 m3 , VHMO: 51 ± 26 x 10-6 m3 , and volumetric contraction: 11 ± 3%, which do not present significant differences with respect to conventional drying. The values of compression parallel to the grain were: ELPHMO: 6 ± 2 x 106 kg/m2 , MRHMO: 6 ± 2 x 106 kgm2 and MOEHMO: 4 ± 1 x 108 kg/m2 , ELPEH: 3,0 ± 0.5 kg/m2 , MREH: 3,5 ± 0.64 kg/m2 and MOEEH: 2,3 ± 0.6 kg/m2 , and not show differences with respect to conventional drying. The only anatomical alteration observed was an increase in spiral cracks in the walls of the tracheids and does not seem to have an impact on the evaluated properties. It was concluded that microwave exposure does not alter the studied properties and is a reliable method for drying.

https://doi.org/10.18845/tm.v35i2.5435

12.

Variabilidad de densidad en sentido radial y dentro de un anillo de crecimiento en Pinus caribaea var. hondurensis de 25 años de edad
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Márquez-Carrero, Gabrialy

; Valero, Styles W.

; León-Hernández, Williams J.

; Gutiérrez-Gotero, Ilvania J.

; Maldonado-Rangel, Julio C.

Revista Tecnología en Marcha

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Jun 2022, Volumen 35 Nº 2 Paginas 115 - 124

Resumen: Es En | Texto: Es En | PDF: Es | PDF: En

Resumen El presente trabajo corresponde al estudio de la densidad de madera seca al aire en 6 árboles de Pinus caribaea var. hondurensis (Sénécl) W. Barret & Golfari (Pinaceae) provenientes de plantaciones de 25 años de edad establecidas en Uverito (estado Monagas, Venezuela). Se tomaron muestras en 3 posiciones de la sección transversal del tallo: adyacencias de médula (muestra de todo el anillo de crecimiento), y a la mitad del radio (muestra en madera temprana y madera tardía) y adyacencias de zona cambial (muestra de todo el anillo de crecimiento). La densidad se determinó bajo la Norma DIN 52-182. A través de la sección transversal se encontró un incremento de la densidad desde las adyacencias de médula hacia la zona cambial (0,595 en adyacencias de médula; 0,681 en el punto medio y 0,820 g/cm³ en las adyacencias de la zona cambial). Por otra parte, el peso específico de madera tardía (0,806 g/cm³) mostró valores notablemente superiores con respecto a la madera temprana (0,557 g/cm³). De acuerdo a la prueba de Tukey (α = 0,01), existen diferencias estadísticamente significativas entre el peso específico de adyacencias de médula con respecto a las cercanías del cambium; así como también las diferencias encontradas entre madera temprana y madera tardía del anillo de crecimiento tuvieron significancia estadística.

Abstract This paper deals about air-dry density in wood from six trees of Pinus caribaea var. hondurensis (Sénécl) W. Barret & Golfari (Pinaceae) from 25 years old plantations growing in Uverito (Monagas state, Venezuela). Samples were taken in three positions of cross section: near of pith (all growth ring), middle point (sample for early wood and sample for late wood) and near of cambium (all growth ring). Density was obtained according DIN 52-182. Density grows from pith to cambium (0,595 near of pith; 0,681 in middle zone and 0,820 g/cm³ near of cambium). In late wood, we found higher values in air-dry density (0,806 g/cm³) in comparation with early wood (0,557 g/cm³). According Tukey test (α = 0,01), there are significatives differences between airdry density in pith zone-cambial zone and between early and late wood.

https://doi.org/10.18845/tm.v35i2.5866

13.

How ADP students navigate enablements and constraints of the programme: an exploration of structure and agency
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Mogashana, D.

; Case, J. M.

; Williams, K.

South African Journal of Higher Education

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May 2022, Volumen 36 Nº 2 Paginas 204 - 221

Resumen: En | Texto: En | PDF: En

Academic Development Programmes (ADPs), or Extended Curriculum Programmes (ECPs), continue to play a central role in increasing access to previously marginalised students in higher education in South Africa. Using Archer's morphogenetic approach, this study examines how a group of ADP students "made their way" through their engineering undergraduate studies. Twelve students in their fourth year of study were interviewed three times and selected university documents were analysed. The authors found that the fragmented curriculum, shortened consolidation and examination periods, and unfavourable examination timetables potentially constrained the students' aspirations. In addition, the mainstream students and lecturers' ideas about ADP students worsened their experience of marginalisation and exception. We also found that students experienced the mainly black student enrolment of the ADP as racial discrimination. The findings indicate that students found themselves in enormously constrained circumstances, but they also exhibited what Archer calls "corporate agency" and different "modes of reflexivity" to overcome some of these constraints. We argue that the establishment of Academic Development Programmes as separate from mainstream curricula, while enabling access to some extent, may have unintended consequences of also constraining the students for whom they are designed.

https://doi.org/10.20853/36-2-4698 15 descargas

14.

O Impacto da COVID-19 no Diagnóstico de Doenças Cardíacas na América Latina Uma Subanálise do INCAPS COVID
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Cerci, Rodrigo Julio

; Vitola, João Vicente

; Paez, Diana

; Zuluaga, Alejandro

; Bittencourt, Marcio Sommer

; Sierra-Galan, Lilia M.

; Carrascosa, Patricia

; Campisi, Roxana

; Gutierrez-Villamil, Claudia

; Peix, Amalia

; Chambers, Duane

; Velez, Mayra Sánches

; Alvarado, Carla M. G.

; Ventura, Ana C. F.

; Maldonado, Alejandro

; Castanos, Alfredo P.

; Diaz, Teresa C.

; Herrera, Yariela

; Vasquez, Manuel C.

; Arrieta, Ana A.

; Mut, Fernando

; Hirschfeld, Cole

; Malkovskiy, Eli

; Goebel, Benjamin

; Cohen, Yosef

; Randazzo, Michael

; Shaw, Leslee J.

; Williams, Michelle C.

; Villines, Todd C.

; Better, Nathan

; Dorbala, Sharmila

; Raggi, Paolo

; Pascual, Thomas N. B.

; Pynda, Yaroslav

; Dondi, Maurizio

; Einstein, Andrew J.

Arquivos Brasileiros de Cardiologia

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Abr 2022, Volumen 118 Nº 4 Paginas 745 - 753

Resumen: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo Fundamento A pandemia de COVID-19 interferiu na prestação de atendimento a doenças cardiovasculares na América Latina. No entanto, o efeito da pandemia nos volumes de procedimentos cardíacos diagnósticos ainda não foi quantificado. Objetivo Avaliar (1) o impacto de COVID-19 nos volumes de diagnóstico cardíaco na América Latina e (2) determinar sua relação com a incidência de casos de COVID-19 e as medidas de distanciamento social. Métodos A International Atomic Energy Agency realizou uma pesquisa mundial avaliando mudanças nos volumes diagnósticos cardíacos decorrentes da COVID-19. Foram obtidos os volumes diagnósticos cardíacos dos locais participantes para março e abril de 2020 e comparados com março de 2019. Foram coletados dados de distanciamento social a partir dos Relatórios de mobilidade da comunidade de Google e a incidência de COVID-19 por país a partir de Our World in Data. Resultados Foram realizadas pesquisas em 194 centros que realizam procedimentos diagnósticos cardíacos, em 19 países da América Latina. Em comparação com o mês de março de 2019, os volumes dos procedimentos diagnósticos cardíacos diminuíram 36% em março de 2020 e 82% em abril de 2020.As maiores reduções ocorreram em relação aos testes de estresse ecocardiográfico (91%), testes ergométricos de esteira (88%) e escore de cálcio por tomografia computadorizada (87%), com pequenas variações entre as sub-regiões da América Latina. As mudanças em padrões de distanciamento social (p < 0,001) estavam mais fortemente associadas com a redução do volume do que a incidência de COVID-19 (p = 0,003). Conclusões A COVID-19 foi associada a uma redução significativa de procedimentos diagnósticos cardíacos na América Latina, a qual foi mais relacionada ao distanciamento social do que ao aumento da incidência da COVID-19. São necessários melhor equilíbrio e timing de medidas de distanciamento social e planejamento para manter o acesso ao atendimento médico durante um surto pandêmico, especialmente em regiões com alta mortalidade cardiovascular.

Abstract Background The COVID-19 pandemic has disrupted the delivery of care for cardiovascular diseases in Latin America. However, the effect of the pandemic on the cardiac diagnostic procedure volumes has not been quantified. Objective To assess (1) the impact of COVID-19 on cardiac diagnostic volumes in Latin America and (2) determine its relationship with COVID-19 case incidence and social distancing measures. Methods The International Atomic Energy Agency conducted a worldwide survey assessing changes in cardiac diagnostic volumes resulting from COVID-19. Cardiac diagnostic volumes were obtained from participating sites for March and April 2020 and compared to March 2019. Social distancing data were collected from Google COVID-19 community mobility reports and COVID-19 incidence per country from the Our World in Data. Results Surveys were conducted in 194 centers performing cardiac diagnostic procedures, in 19 countries in Latin America. Procedure volumes decreased 36% from March 2019 to March 2020, and 82% from March 2019 to April 2020. The greatest decreases occurred in echocardiogram stress tests (91%), exercise treadmill tests (88%), and computed tomography calcium scores (87%), with slight variations between sub-regions of Latin America. Changes in social distancing patterns (p < 0.001) were more strongly associated with volume reduction than COVID-19 incidence (p = 0.003). Conclusions COVID-19 was associated with a significant reduction in cardiac diagnostic procedures in Latin America, which was more related to social distancing than to the COVID-19 incidence. Better balance and timing of social distancing measures and planning to maintain access to medical care is warranted during a pandemic surge, especially in regions with high cardiovascular mortality.

https://doi.org/10.36660/abc.20210388

15.

Densidad seca al aire y características cuantitativas de elementos xilemáticos de conducción en 10 especies de Malvaceae en Venezuela
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Uzcátegui-Rojas, Mariangel

; Valero, Styles W.

; León-Hernández, Williams J.

Revista Tecnología en Marcha

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Mar 2022, Volumen 35 Nº 1 Paginas 14 - 27

Resumen: Es En | Texto: Es En | PDF: Es | PDF: En

Resumen Se presenta el estudio de la relación entre la densidad seca al aire y características cuantitativas de los vasos (frecuencia y diámetro de vasos, área de lumen) para diez especies de Malvaceae que crecen en Venezuela: Catostemma commune, Eryotheca globosa, Ochroma pyramidale, Pachira quinata, Guazuma ulmifolia, Apeiba tibourbou, Heliocarpus americanus, Uladendron codesurii, Sterculia apetala y Sterculia pruriens. La densidad se determinó en muestras acondicionadas al 12 % de humedad y para la medición de las características de los vasos se prepararon láminas de secciones transversales utilizando los procedimientos convencionales de microtecnia xilemática. Las mayores frecuencias y menores diámetros de vasos se presentaron en Guazuma ulmifolia y Uladendron codesurii; mientras que las menores frecuencias y mayores diámetros de vasos los presentaron especies de las subfamilias Bombacoideae y Sterculioideae. La densidad seca al aire mostró un alto grado de variación, encontrándose especies que van desde la categoría de muy baja densidad (Ochroma pyramidale, Pachira quinata, Apeiba tibourbou, Heliocarpus americanus, Sterculia apetala) hasta muy alta densidad (Uladendron codesurii). La relación entre la densidad y las características de los vasos presentó una baja correlación lo que indica la posible existencia de otras características anatómicas que ejercen mayor influencia sobre esta propiedad física.

Abstract This research is about the relation between air dry density and quantitative features of vessels (frequency and diameter, lumen area) for ten species of Malvaceae from Venezuela: Catostemma commune, Eryotheca globosa, Ochroma pyramidale, Pachira quinata, Guazuma ulmifolia, Apeiba tibourbou, Heliocarpus americanus, Uladendron codesurii, Sterculia apetala and Sterculia pruriens. Density was determined in samples with moisture content equal to 12 % and measures of vessels features were realized in slides samples of cross sections using standards procedures in xylem microtechnique. Higher vessels frequencies and lower diameters were observed in Guazuma ulmifolia and Uladendron codesurii and lower frequencies and higher diameters were observed in species from Bombacoideae and Sterculioideae subfamilies. Air dry density shows a high variation, ranging from very low density (Ochroma pyramidale, Pachira quinata, Apeiba tibourbou, Heliocarpus americanus, Sterculia apetala) to very high density (Uladendron codesurii). A low correlation between density and vessels features was found and its possible that others wood anatomy features have a higher effect over wood density for Malvaceae.

https://doi.org/10.18845/tm.v35i1.5436

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