UV Radiation Effect in New Materials Developed for the Construction of Beehives.

In recent decades, there has been an increasing focus on the alarming decline in global bee populations, given their critical ecological contributions to natural pollination and biodiversity. This decline, marked by a substantial reduction in bee colonies in forested areas, has serious implications for sustainable beekeeping practices and poses a broader risk to ecological well-being. Addressing these pressing issues requires innovative solutions, one of which involves the development and fabrication of beehives crafted from composite materials that are ecologically compatible with bee biology. Importantly, these materials should also exhibit a high resistance to environmental factors, such as ultraviolet (UV) radiation, in order to maintain their mechanical integrity and longevity. To investigate this, we conducted accelerated UV degradation tests on a variety of composite materials to rapidly assess their susceptibility to UV-induced changes. High-density polyethylene (HDPE) served as the matrix material and was reinforced with natural fibers, specifically fique fibers (Furcraea bedinghausii), banana fibers, and goose feathers. Our findings indicate that UV radiation exposure results in a noticeable reduction in the tensile strength of these materials. For example, wood composites experienced a 48% decline in tensile strength over a 60-day period, a rate of deterioration notably higher than that of other tested composite materials. Conversely, HDPE composites fortified with banana fibers initially demonstrated tensile strengths exceeding 9 MPa and 10 MPa. Although these values gradually decreased over the observation period, the composites still displayed favorable stress-strain characteristics. This research underscores the substantial influence of UV radiation on the longevity and efficacy of beehive materials, which in turn affects the durability of natural wood hives exposed to these environmental factors. The resultant increased maintenance and replacement costs for beekeepers further emphasize the need for judicious material selection in beehive construction and point to the viability of the composite materials examined in this study.

Electrospun Scaffolds of Polylactic Acid, Collagen, and Amorphous Calcium Phosphate for Bone Repair.

Most electrospun scaffolds for bone tissue engineering typically use hydroxyapatite (HA) or beta tricalcium phosphate (ß-TCP). However, the biological activity of these crystalline compounds can be limited due to their low solubility. Therefore, amorphous calcium phosphate (ACP) may be an alternative in bone repair scaffolds. This study analyzes the morphology, porosity, mechanical strength, and surface chemistry of electrospun scaffolds composed of polylactic acid and collagen integrated with hydroxyapatite (MHAP) or amorphous calcium phosphate (MACP). In addition, the in vitro biocompatibility, osteogenic differentiation, and growth factor production associated with bone repair using human Wharton's jelly-derived mesenchymal stem cells (hWJ-MSCs) are evaluated. The results show that the electrospun MHAP and MACP scaffolds exhibit a fibrous morphology with interconnected pores. Both scaffolds exhibit favorable biocompatibility and stimulate the proliferation and osteogenesis of hWJ-MSCs. However, cell adhesion and osteocalcin production are greater in the MACP scaffold compared to the MHAP scaffold. In addition, the MACP scaffold shows significant production of bone-repair-related growth factors such as transforming growth factor-beta 1 (TGF-ß1), providing a solid basis for its use in bone tissue engineering.

Improvement of the Polyhydroxyalkanoates Recovery from Mixed Microbial Cultures Using Sodium Hypochlorite Pre-Treatment Coupled with Solvent Extraction.

The use of mixed microbial cultures (MMC) and organic wastes and wastewaters as feed sources is considered an appealing approach to reduce the current polyhydroxyalkanoates (PHAs) production costs. However, this method entails an additional hurdle to the PHAs downstream processing (recovery and purification). In the current work, the effect of a sodium hypochlorite (NaClO) pre-treatment coupled with dimethyl carbonate (DMC) or chloroform (CF) as extraction solvents on the PHAs recovery efficiency (RE) from MMC was evaluated. MMC were harvested from a sequencing batch reactor (SBR) fed with a synthetic prefermented olive mill wastewaster. Two different carbon-sources (acetic acid and acetic/propionic acids) were employed during the batch accumulation of polyhydroxybutyrate (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) from MMC. Obtained PHAs were characterized by 1H and 13C nuclear magnetic resonance, gel-permeation chromatography, differential scanning calorimetry, and thermal gravimetric analysis. The results showed that when a NaClO pre-treatment is not added, the use of DMC allows to obtain higher RE of both biopolymers (PHB and PHBV), in comparison with CF. In contrast, the use of CF as extraction solvent required a pre-treatment step to improve the PHB and PHBV recovery. In all cases, RE values were higher for PHBV than for PHB.

Electrospun Ultrafine Cationic Cellulose Fibers Produced from Sugarcane Bagasse for Potential Textile Applications.

Sugarcane bagasse (SCB) is an abundant by-product of sugar refining that can be utilized as a raw material for cellulose isolation for several industrial applications. Electrospinning has garnered attention in recent years because it allows the preparation of cellulosic materials with unique properties. In this study, cellulose was isolated from sugarcane bagasse and acetylated to fabricate fine acetate cellulose fibers through electrospinning. Subsequently, the electrospun fibers were deacetylated and cationized in order to produce functionalized materials with potential textile applications. The functional fibers were colored with an anionic dye (vinyl sulfone) with and without the presence of salt and were evaluated according to dye fixation, color attributes, morphological characteristics, and thermal stability. Cationic cellulose fibers that were dyed without added salt were found to be brighter and demonstrated better color fixation than those with added salt. In addition, morphological analysis performed using scanning electron microscopy demonstrated that cationized fibers dyed without added salt were better preserved at this stage. The cationic fiber also evidenced a high-temperature resistance, exhibiting a degradation temperature above 236 °C. The results suggest that cellulose fibers dyed in this manner can potentially be considered for use in textile applications due to their suitable dye fixation and tunable porosity (i.e., breathability).

Fabricación de nanofibras de TiO2/ZnO para aplicaciones de almacenamiento de energía / Fabrication of TiO2/ZnO nanofibers for energy storage applications / Fabricação de nanofibras TiO2/ZnO para aplicações de armazenamento de energia

Resumen Se estudiaron nanofibras de TiO2/ZnO preparadas por calcinación de fibras precursoras de poli (vinil acetato), isopropóxido de titanio y nano polvo de zinc elaboradas por la técnica de electrohilado. La estructura y la morfología de las nanofibras de TiO2/ZnO y fibras precursoras se caracterizaron por Microscopia Electrónica de Barrido (SEM), Microscopia Electrónica de Barrido de Emisión de Campo equipado con Espectroscopia Dispersiva de Rayos X (FESEM-EDS), Espectroscopia de Infrarrojo con Transformada de Fourier (FTIR) y Difracción de Rayos X (XRD). El análisis XRD mostró la estructura cristalina de los óxidos de titanio (anatasa) y de zinc (wurzita hexagonal), después de calcinar las fibras precursoras a 500°C. Las microfotografías de SEM muestran que tanto las fibras precursoras como las nanofibras forman redes uniformes y buena morfología. Estas nanofibras de dióxido de titanio /óxido de zinc presentan buen área de superficie y diámetros de 200 nm apropiados que podrían ser de aplicación potencial en el campo de energía renovable, en particular, para la fabricación de celdas solares.

Abstract The TiO2 /ZnO nanofibers prepared by the calcination of polyvinyl acetate of precursor fibers, titanium isopropoxide and nano zinc powder produced by the electrospinning technique were studied. The structu-re and morphology of TiO2 /ZnO nanofibers and precursor fibers were characterized by Scanning Electron Microscopy (SEM), Field Emission Scanning Electron Microscopy coupled to Energy Dispersive X-ray spectroscopy (FESEM-EDS), Fourier Transform Infrared Spectroscopy (FTIR) and XRD (X Ray Diffraction). XRD analysis displayed crystalline structures of titanium oxides (anatase) and zinc (hexagonal wurzite), after calcining the precursor fibers at 500 °C. SEM microphotographs display that both precursor fibers and nanofibers form uniform networks and good morphology. These titanium dioxide / zinc oxide nanofibers get good surface area and appropriate 200 nm diameters which could potentially be applied in the renewable energy field, particularly for solar cells manufacturing.

Resumo Nanofibras de TiO2 /ZnO preparado por calcinação de fibras precursoras de poli (acetato de vinila), isopropóxido de titânio e pó nano de zinco produzidos por eletrofiação técnica estudada. A estrutura e morfologia das nanofibras de TiO2/ ZnO e fibras precursores foram caracterizados por microscopia eletrônica de varredura (SEM), Microscopia eletrônica de varredura de emissão de campo equipada com espectroscopia de raios-X dispersiva (FESEM-EDS), Espectroscopia de Fourier Transform Infrared (FTIR) e difração de raios X (DRX). A análise de XRD mostrou a formação de estruturas de cristal de óxido de titânio (anatase) e zinco (wurtzita hexagonal), depois de fibras precursoras de calcinação a 500 °C. Micrografias mostram que tanto o precursor e fibras nanofibras uniformes formar redes e boa morfologia. Estas nanofibras de dióxido de titanio /óxido de zinco apresentam bom área de superfície e diâmetros de 200 nm apropriados que poderiam ser de aplicativo potencial no campo de energia renovável, em particular, para a fabricação de celas solares.

First Colombian consensus on congenital Chagas and clinical approach for women of child-bearing age diagnosed with Chagas / Primer consenso colombiano sobre Chagas congénito y orientación clínica a mujeres en edad fértil con diagnóstico de Chagas

Congenital transmission of Chagas disease has not been extensively studied in Colombia, and there are no standardized processes in the health system regarding the specific diagnosis, treatment and follow-up of this disease. To generate recommendations on congenital Chagas disease and Chagas in women of childbearing age in Colombia, a consensus of experts was developed. An extensive literature search through the Medline database was carried out using the MeSH terms: «Chagas disease/congenital¼, «prevention and control¼, «diagnosis¼, «therapeutics¼ and «pregnancy¼. Appropriate abstracts were selected and the full texts were analyzed. The relevant information was synthesized, classified, and organized into tables and figures and was presented to a panel of experts, which was composed of 30 professionals from various fields. Based on the Delphi methodology, three rounds of consultation were conducted. The first and second rounds were based on electronic questionnaires that measured the level of consensus of each question among the participants. The third round was based on a face-to-face discussion focusing on those questions without consensus in the previous consultations. The evidence was adapted to national circumstances on a case-by-case basis, and the content the final document was approved. These recommendations are proposed for use in routine medical practice by health professionals in Colombia.

La transmisión congénita de la enfermedad de Chagas ha sido poco estudiada en Colombia y existen pocos procedimientos rutinarios en el sistema de salud para el manejo de esta enfermedad. Por ello se desarrolló un consenso de expertos dirigido a generar recomendaciones de diagnóstico y tratamiento de Chagas con- génito y orientación a mujeres en edad fértil. Con ese propósito se realizó una búsqueda extensiva de la literatura, empleando una combinación de términos Mes (Chagas, Chagas congénito, prevención, control, diagnóstico, tratamiento y embarazo) para reflejar el estado del arte en cada tema de interés. Después de ello, se leyeron los resúmenes y aquellos seleccionados para análisis del texto completo. La literatura relevante se sintetizo, clasifico y organizo en tablas y se presentó al panel de expertos, el cual estaba constituido por 30 profesionales en diferentes áreas. Mediante la metodología Delphi se realizaron 2 rondas de cuestionarios virtuales y una reunión presencial en los cuales se evaluaron los niveles de acuerdo entre los participantes. Los puntos con falta de consenso durante las 2 rondas virtuales se expusieron durante las mesas de discusión en la ronda presencial. La evidencia utilizada se adaptó a las particularidades nacionales según el caso y se aprobó el contenido del documento final. Se propone que estas recomendaciones sean usadas por profesionales de la salud en Colombia.

Transmission scenarios of major vector-borne diseases in Colombia, 1990-2016.

Introducción. Las enfermedades transmitidas por vectores representan más de 17 % de todas las enfermedades infecciosas y causan anualmente un millón de defunciones a nivel mundial. En Colombia, la malaria, el dengue, la enfermedad de Chagas y las leishmaniasis son condiciones endemoepidémicas persistentes.Objetivo. Determinar el comportamiento epidemiológico de las enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016.Materiales y métodos. Se hizo un estudio descriptivo del comportamiento epidemiológico de las principales enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016, con la información proveniente de fuentes oficiales secundarias.Resultados. En el periodo estudiado se registraron 5'360.134 casos de enfermedades transmitidas por vectores, de los cuales 54,7 % fueron de malaria y 24,9 % de dengue. Estos casos concentraron el 80 % de la carga acumulada de casos de enfermedades transmitidas por vectores. Las medianas de las tasas de incidencia fueron 1.371 y 188 por 100.00 habitantes para malaria y dengue, respectivamente. Además, los casos de chikungunya fueron 774.831 desde su introducción en el 2014 y, los de Zika, 117.674 desde su aparición en 2015. En las zonas rurales predominaron las enfermedades parasitarias transmitidas por vectores como la malaria, las leishmaniasis y la enfermedad de Chagas. A nivel urbano, predominaron el dengue, el chikungunya y el Zika.Conclusiones. La transmisión en Colombia de estas enfermedades es persistente en las zonas urbanas y en las rurales, y de tipo endemoepidémico en los casos de malaria, dengue, leishmaniasis y enfermedad de Chagas. Dicha transmisión se ha dado de manera focalizada y con patrones variables de intensidad. Asimismo, se mantienen las condiciones que han favorecido la transmisión emergente de nuevas arbovirosis.

Epidemiología de las principales enfermedades transmitidas por vectores en Colombia, 1990-2016 / Transmission scenarios of major vector-borne diseases in Colombia, 1990-2016

Resumen Introducción. Las enfermedades transmitidas por vectores representan más de 17 % de todas las enfermedades infecciosas y causan anualmente un millón de defunciones a nivel mundial. En Colombia, la malaria, el dengue, la enfermedad de Chagas y las leishmaniasis son condiciones endemoepidémicas persistentes. Objetivo. Determinar el comportamiento epidemiológico de las enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016. Materiales y métodos. Se hizo un estudio descriptivo del comportamiento epidemiológico de las principales enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016, con la información proveniente de fuentes oficiales secundarias. Resultados. En el periodo estudiado se registraron 5'360.134 casos de enfermedades transmitidas por vectores, de los cuales 54,7 % fueron de malaria y 24,9 % de dengue. Estos casos concentraron el 80 % de la carga acumulada de casos de enfermedades transmitidas por vectores. Las medianas de las tasas de incidencia fueron 1.371 y 188 por 100.00 habitantes para malaria y dengue, respectivamente. Además, los casos de chikungunya fueron 774.831 desde su introducción en el 2014 y, los de Zika, 117.674 desde su aparición en 2015. En las zonas rurales predominaron las enfermedades parasitarias transmitidas por vectores como la malaria, las leishmaniasis y la enfermedad de Chagas. A nivel urbano, predominaron el dengue, el chikungunya y el Zika. Conclusiones. La transmisión en Colombia de estas enfermedades es persistente en las zonas urbanas y en las rurales, y de tipo endemoepidémico en los casos de malaria, dengue, leishmaniasis y enfermedad de Chagas. Dicha transmisión se ha dado de manera focalizada y con patrones variables de intensidad. Asimismo, se mantienen las condiciones que han favorecido la transmisión emergente de nuevas arbovirosis.

Abstract Introduction: Vector-borne diseases account for more than 17% of all infectious diseases and annually they cause one million deaths worldwide. In Colombia, malaria, dengue, Chagas disease, and leishmaniasis are persistent endemo-epidemic events. Objective: To determine the behavior and transmission scenarios of vector-borne diseases in Colombia between 1990 and 2016. Materials and methods: We conducted a descriptive study on the epidemiological behavior of the main vector-borne diseases in Colombia between 1990 and 2016 based on information from official secondary sources. Results: During the study period, there were 5,360,144 cases of vector-borne diseases, 54.7% of which were due to malaria and 24.9% to dengue, accounting for 80% of the cumulative disease burden of vector-borne disease cases. The median incidence rates were 1,371 and 188 per 100,000 inhabitants for malaria and dengue, respectively. In addition, emerging events such as Chikungunya registered 774,831 cases since its introduction in 2014, while 117,674 Zika fever cases were reported since its emergence in 2015. In rural settings, parasitic vector-borne diseases such as malaria, leishmaniasis and Chagas disease predominated, while in urban scenarios dengue, chikungunya and Zika were predominant. Conclusions: Persistent epidemic and endemic transmission of vector-borne diseases in urban and rural settings in Colombia was observed mainly in the case of malaria, dengue, leishmaniasis and Chagas disease. Such transmission was focused and had variable intensity patterns. On the other hand, the conditions that have favored the emergence of new arboviruses persist.

Primer consenso colombiano sobre Chagas congénito y orientación clínica a mujeres en edad fértil con diagnóstico de Chagas / First Colombian consensus on congenital Chagas and clinical approach to women of fertile age diagnosed with Chagas

La transmisión congénita de la enfermedad de Chagas ha sido poco estudiada en Colombia y existen pocos procedimientos rutinarios en el sistema de salud para el manejo de esta enfermedad. Por ello se desarrolló un consenso de expertos dirigido a generar recomendaciones de diagnóstico y tratamiento de Chagas congénito y orientación a mujeres en edad fértil. Con ese propósito se realizó una búsqueda extensiva de la literatura, empleando una combinación de términos MeSH (Chagas, Chagas congénito, prevención, control, diagnóstico, tratamiento y embarazo) para reflejar el estado del arte en cada tema de interés. Después de ello, se leyeron los resúmenes y aquellos seleccionados para análisis del texto completo. La literatura relevante se sintetizó, clasificó y organizó en tablas y se presentó al panel de expertos, el cual estaba constituido por 30 profesionales en diferentes áreas. Mediante la metodología Delphi se realizaron 2 rondas de cuestionarios virtuales y una reunión presencial en los cuales se evaluaron los niveles de acuerdo entre los participantes. Los puntos con falta de consenso durante las 2 rondas virtuales se expusieron durante las mesas de discusión en la ronda presencial. La evidencia utilizada se adaptó a las particularidades nacionales según el caso y se aprobó el contenido del documento final. Se propone que estas recomendaciones sean usadas por profesionales de la salud en Colombia.

Congenital transmission of Chagas disease has not been extensively studied in Colombia, and there are no standardized processes in the health system regarding the specific diagnosis, treatment and follow-up of this disease. In order to generate recommendations on congenital Chagas disease and Chagas in women of childbearing age in Colombia, a consensus of experts was developed. An extensive literature search through the Medline database was carried out using the MeSH terms: " Chagas disease/congenital " , " prevention and control " , " diagnosis " , " therapeutics " and " pregnancy " . Appropriate abstracts were selected and the full texts were analyzed. The relevant information was synthesized, classified, and organized into tables and figures and was presented to a panel of experts, which was composed of 30 professionals from various fields. Based on the Delphi methodology, three rounds of consultation were conducted. The first and second rounds were based on electronic questionnaires that measured the level of consensus of each question among the participants. The third round was based on a face-toface discussion focusing on those questions without consensus in the previous consultations. The evidence was adapted to national circumstances on a case-by-case basis, and the content the final document was approved. These recommendations are proposed for use in routine medical practice by health professionals in Colombia.

Ultrahigh-sensitivity temperature fiber sensor based on multimode interference.

The proposed sensing device relies on the self-imaging effect that occurs in a pure silica multimode fiber (coreless MMF) section of a single-mode-multimode-single-mode (SMS)-based fiber structure. The influence of the coreless-MMF diameter on the external refractive index (RI) variation permitted the sensing head with the lowest MMF diameter (i.e., 55 µm) to exhibit the maximum sensitivity (2800 nm/RIU). This approach also implied an ultrahigh sensitivity of this fiber device to temperature variations in the liquid RI of 1.43: a maximum sensitivity of -1880 pm/°C was indeed attained. Therefore, the results produced were over 100-fold those of the typical value of approximately 13 pm/°C achieved in air using a similar device. Numerical analysis of an evanescent wave absorption sensor was performed, in order to extend the range of liquids with a detectable RI to above 1.43. The suggested model is an SMS fiber device where a polymer coating, with an RI as low as 1.3, is deposited over the coreless MMF; numerical results are presented pertaining to several polymer thicknesses in terms of external RI variation.