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1.
Photochem Photobiol ; 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39311497

RESUMEN

Consuming microbiologically-contaminated water is the primary cause of many water-borne diseases and deaths worldwide. Governments aim at providing drinking water for vulnerable populations, especially through low-cost interventions. Therefore, the solar disinfection (SODIS) of such pathogens provides a simple and cost-effective way to obtain good quality water. In this procedure, PET bottles are filled with contaminated water and exposed to sunlight for 1-2 days. To accelerate decontamination, methylene blue (MB) dye added as a photocatalyst, boosts singlet oxygen generation upon absorbing red-band sunlight. This study explores the use of a Sunlight Simulator (SSL) device to research and standardize the SODIS method with a vital dye as MB. PET bottles were filled with artificially-contaminated water with Streptococcus epidermidis and Deinococcus radiodurans Gram-positive bacteria, Escherichia coli and Salmonella typhimurium Gram-negative bacteria, or bacteriophage λ as well. In all experiments, 50 ng/mL MB ensued a synergistic lethal effect after SSL exposure. The results indicate that bacterial and bacteriophage inactivation can be achieved in shorter times with MB-SSL treatment compared to SSL without MB. In this sense, when compared to previous sunlight-SODIS results, the SSL source is a reliable tool to study the parameters of both SODIS and MB-SODIS protocols, and also a feasible tool to afford assays whenever there are unfavorable climate conditions.

2.
Heliyon ; 10(12): e32894, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38994084

RESUMEN

This study investigated the novel application of Fe-TiO2-allophane catalysts with 6.0 % w/w of iron oxide and two TiO2 proportions (10 % and 30 % w/w) for degrading atrazine (ATZ) using the heterogeneous dual-effect (HDE) process under sunlight. Comparative analyses with Fe-allophane and TiO2-allophane catalysts were conducted in both photocatalysis (PC) and HDE processes. FTIR spectra reveal the unique hydrous feldspathoids structure of allophane, showing evidence of new bond formation between Si-O groups of allophane clays and iron hydroxyl species, as well as Si-O-Ti bonds that intensified with higher TiO2 content. The catalysts exhibited an anatase structure. In Fe-TiO2-allophane catalysts, iron oxide was incorporated through the substitution of Ti4+ by Fe3+ in the anatase crystal lattice and precipitation on the surface of allophane clays, forming small iron oxide particles. Allophane clays reduced the agglomeration and particle size of TiO2, resulting in an enhanced specific surface area and pore volume for all catalysts. Iron oxide incorporation decreased the band gap, broadening the photoresponse to visible light. In the PC process, TiO2-allophane achieves 90 % ATZ degradation, attributed to radical species from the UV component of sunlight. In the HDE process, Fe-TiO2-allophane catalysts exhibit synergistic effects, particularly with 30 % w/w TiO2, achieving 100 % ATZ degradation and 85 % COD removal, with shorter reaction time as TiO2 percentage increased. The HDE process was performed under less acidic conditions, achieving complete ATZ degradation after 6 h without iron leaching. Consequently, Fe-TiO2-allophane catalysts are proposed as a promising alternative for degrading emerging pollutants under environmentally friendly conditions.

3.
Actas Dermosifiliogr ; 115(3): 288-292, 2024 Mar.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37244395

RESUMEN

Few reports describing an association between UV radiation and fixed skin eruptions have been published since 1975. These reactions have received various names, including fixed sunlight eruption, fixed exanthema due to UV radiation, and broad-spectrum abnormal localized photosensitivity syndrome. We present a series of 13 patients (4 men [30.8%] and 9 women [69.2%]) aged between 28 and 56 years who were evaluated for fixed eruptions induced by UV radiation at a dermatology referral hospital in Bogotá, Colombia. The lesions were located on the inner thighs, buttocks, popliteal region, anterior and posterior axilla, and dorsum of the feet. Photoprovocation reproduced lesions in all the affected areas, and histopathology showed changes similar to those seen in fixed drug eruptions. While these UV-provoked reactions may be a type of fixed skin eruption, we cannot rule out that they may also be a distinct condition that simply shares a pathogenic mechanism with fixed eruptions.


Asunto(s)
Exantema , Trastornos por Fotosensibilidad , Masculino , Humanos , Femenino , Adulto , Persona de Mediana Edad , Colombia/epidemiología , Luz Solar/efectos adversos , Trastornos por Fotosensibilidad/etiología , Trastornos por Fotosensibilidad/patología , Rayos Ultravioleta/efectos adversos , Exantema/etiología
4.
Rev. bras. oftalmol ; 83: e0021, 2024. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1559592

RESUMEN

ABSTRACT Maculopathy from prolonged exposure to solar light is a rare but well-recognized clinical entity of vision loss and macular damage. Photochemical damage precedes visual decline, and in mild cases, vision usually returns fully or partially. With the advancement of humanity, other forms of macular injuries induced by light radiation have emerged, increasing the group of photic maculopathies. In this report, we describe the cases of five patients where a diagnosis of photic maculopathy was made based on the anamnesis, clinical findings, and complementary exams. We compare the five cases regarding their similarities and differences, as well as review the literature on the subject.


RESUMO A maculopatia causada pela exposição prolongada à luz solar é uma entidade clínica rara, mas bem reconhecida, de perda de visão e dano macular. O dano fotoquímico precede o declínio visual e em casos leves a visão geralmente retorna total ou parcialmente. Com o avanço da humanidade, surgiram outras formas de lesões maculares induzidas pela radiação luminosa, aumentando o grupo das maculopatias fóticas. Neste relato, descrevemos os casos de cinco pacientes onde o diagnóstico de maculopatia fótica foi feito com base na anamnese, achados clínicos e exames complementares. Comparamos os quatro casos quanto às suas semelhanças e diferenças, bem como revisamos a literatura sobre o assunto.

5.
Chemosphere ; 342: 140132, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37690560

RESUMEN

In this work, complete elimination of Escherichia coli and Salmonella typhimurium was achieved in 120 min using a heterogeneous photo-Fenton process under sunlight at pH 6.5 in distilled water. A face-centered composite central design 22 with one categoric factor and three replicates at the central point was used to evaluate the effect of iron (III) oxide concentration (0.8-3.4 mg L-1), H2O2 (2-10 mg L-1), and the type of iron oxide phase (maghemite and hematite) on the inactivation of both bacteria. The results showed that the amount of catalyst, H2O2 concentration and their interaction were significant factors (p < 0.05) in the elimination of the microorganisms. Thus, under the best conditions (3.4 mg L-1 of iron (III) oxide and 10 mg L-1 of H2O2) in the experimental ranges, complete inactivation of E. coli and S. typhimurium was achieved (6-log reduction) in 120 min using the photo-Fenton treatment with both iron-oxide phases. Furthermore, the photocatalytic elimination of both bacteria by the photo-Fenton process using hematite and maghemite in secondary-treated wastewater effluent was performed obtaining slower inactivation rates (1.2-5.9 times) than in distilled water due to the matrix effect of the effluent from a wastewater treatment plant. Nevertheless, the process continued to be effective in the effluent, achieving complete bacterial elimination in 150 min using the hematite phase. Additionally, the SEM images of the bacterial cells showed that the heterogeneous photo-Fenton treatment generated permanent and irreversible cell damage, resulting in complete cell death.


Asunto(s)
Escherichia coli , Purificación del Agua , Luz Solar , Aguas Residuales , Salmonella typhimurium , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/química , Desinfección/métodos , Hierro/farmacología , Hierro/química , Purificación del Agua/métodos , Agua/farmacología , Oxidación-Reducción
6.
rev.cuid. (Bucaramanga. 2010) ; 14(3): 1-14, 20230901.
Artículo en Inglés | LILACS, BDENF - Enfermería, COLNAL | ID: biblio-1510105

RESUMEN

Introduction: Serum vitamin D levels depend on sunlight, diet, and other factors. Objective: We aimed to determine serum vitamin D levels and evaluate their relationship with anthropometric indicators and lifestyle habits in apparently healthy volunteers. Materials and Methods: In this cross-sectional study (n=75), socio-demographic, anthropometric, and lifestyle habit-related data were collected. Serum vitamin D levels were determined with high performance liquid chromatography, food intake was measured by semiquantitative frequency and nutritional status was assessed by anthropometry. Chi-square test and also principal component analysis were used to analyze the relationship between some variables and vitamin D status. Spearman's test was used to determine correlations between quantitative variables. Results: 73% were women and 61% belonged to medium socio-economic level. Median vitamin D intake was 137 (83.1­227.3) IU/day. Based on body mass index (BMI), 44% individuals had overweight/obesity. The 68% exhibited deficient/insufficient vitamin D levels (Hypovitaminosis D). BMI classification and waist circumference (CW) were not related with vitamin D status; however, activities with higher sun exposure were highly related (p = 0.013). Sun exposure time explained variation in component 2 (16.60%), where most of the individuals with normal level were grouped. Sun exposure time was positively correlated with vitamin D status (r = 0.263; p = 0.023). Discussion: Excess weight and abdominal obesity are not always associated with hypovitaminosis D. Conclusions: The majority of individuals showed hypovitaminosis D but their status was not related with anthropometric indicators. A Sun exposure time was the only factor positively correlated with vitamin D status.


Introducción: Los niveles séricos de vitamina D dependen de la luz solar, la dieta y otros factores. Objetivo: Nuestro objetivo fue determinar los niveles séricos de vitamina D y evaluar su relación con indicadores antropométricos y estilos de vida en voluntarios aparentemente sanos. Materiales y métodos: En este estudio trasversal (n=75) se recogieron datos sociodemográficos, antropométricos y aquellos relacionados con hábitos y estilos de vida. La vitamina D se determinó por cromatografía liquida de alta eficiencia; la ingesta de alimentos, mediante frecuencia semicuantitativa, y el estado nutricional por antropometría. Para analizar la relación entre algunas variables y el estado de la vitamina D se usó la prueba de Chi cuadrado y también el análisis de componentes principales. Se empleó la prueba de Spearman para determinar la correlación entre variables cuantitativas. Resultados: El 73% eran mujeres y el 61% pertenecían a un estrato socioeconómico medio. La mediana de la ingesta de vitamina D fue de 137 (83,1­227,3) UI/día. Según el índice de masa corporal (IMC), el 44% de los individuos tenían sobrepeso/obesidad. El 68% mostro deficiencia/insuficiencia de vitamina D (hipovitaminosis D). La clasificación del IMC y la circunferencia abdominal no se relacionaron con el estado de la vitamina D; sin embargo, las actividades con una mayor exposición solar estuvieron altamente relacionadas (p=0,013). El tiempo de exposición solar explico la variación en el componente 2 (16,60%) donde se agruparon la mayoría de los individuos con niveles normales. El tiempo de exposición solar tuvo una correlación positiva con el estado de la vitamina D (r = 0,263; p = 0,023). Discusión: El exceso de peso y la obesidad abdominal no siempre se relacionan con la hipovitaminosis D. Conclusiones: La mayoría de los individuos presentaron hipovitaminosis D, pero su estado no se relacionó con los indicadores antropométricos. El tiempo de exposición al sol fue el único factor que se correlaciono positivamente con el estado de la vitamina D.


Introdução: Os níveis séricos de vitamina D dependem da luz solar, da dieta e de outros fatores. Objetivo: Nosso objetivo foi determinar os níveis séricos de vitamina D e avaliar sua relação com indicadores antropométricos e hábitos de vida em voluntários aparentemente saudáveis. Materiais e métodos: Neste estudo transversal (n=75), foram coletados dados sociodemográficos, antropométricos e relacionados a hábitos de vida. Os níveis séricos de vitamina D foram determinados por cromatografia liquida de alto desempenho, a ingestão de alimentos foi medida por frequência semiquantitativa e o estado nutricional foi avaliado por antropometria. O teste do qui-quadrado e a análise de componentes principais foram utilizados para analisar a relação entre algumas variáveis e o estado da vitamina D. O teste de Spearman foi usado para determinar as correlações entre as variáveis quantitativas. Resultados: 73% eram mulheres e 61% pertenciam a um nível socioeconômico médio. A ingestão media de vitamina D foi de 137 (83,1-227,3) UI/dia. Com base no índice de massa corporal (IMC), 44% dos indivíduos tinham sobrepeso/obesidade. Os 68% apresentaram níveis deficientes/insuficientes de vitamina D (hipovitaminose D). A classificação do IMC e a circunferência da cintura (CW) não foram relacionadas ao status da vitamina D; entretanto, as atividades com maior exposição ao sol foram altamente relacionadas (p = 0,013). O tempo de exposição ao sol explicou a variação no componente 2 (16,60%), onde a maioria dos indivíduos com nível normal foi agrupada. O tempo de exposição ao sol foi positivamente correlacionado com o status de vitamina D (r = 0,263; p = 0,023). Discussão: O excesso de peso e a obesidade abdominal nem sempre estão associados com a hipovitaminose D. Conclusões: A maioria dos indivíduos apresentou hipovitaminose D, mas seu status não foi relacionado com indicadores antropométricos. O tempo de exposição ao sol foi o único fator positivamente correlacionado com o status da vitamina D.


Asunto(s)
Luz Solar , Vitamina D , Antropometría , Voluntarios Sanos , Estilo de Vida
7.
J Sleep Res ; : e13974, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37370220

RESUMEN

Circadian rhythms are entrained by external factors such as sunlight and social cues, but also depend on internal factors such as age. Adolescents exhibit late chronotypes, but worldwide school starts early in the morning leading to unhealthy sleep habits. Several studies reported that adolescents benefit from later school start times. However, the effect of later school start time on different outcomes varies between studies, and most previous literature only takes into consideration the social clock (i.e. local time of school starting time) but not the solar clock (e.g. the distance between school start time and sunrise). Thus, there is an important gap in the literature: when assessing the effect of a school start time on chronotype and sleep of adolescents at different locations and/or seasons, the solar clock might differ and, consistently, the obtained results. For example, the earliest school start time for adolescents has been suggested to be 08:30 hours, but this school start time might correspond to different solar times at different times of the year, longitudes and latitudes. Here, we describe the available literature comparing different school start times, considering important factors such as geographic position, nationality, and the local school start time and its distance to sunrise. Then, we described and contrasted the relative role of both social and solar clocks on the chronotype and sleep of adolescents. As a whole, we point and discuss a gap in literature, suggesting that both clocks are relevant when addressing the effect of school start time on adolescents' chronotype and sleep.

8.
Nutrition ; 110: 112008, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36940625

RESUMEN

OBJECTIVES: This study aimed to evaluate the association of vitamin D with sleep quality during the COVID-19 pandemic and the influence of daily sunlight on this association. METHODS: This cross-sectional, population-based study among adults stratified by multistage probability cluster sampling was conducted from October to December 2020 in the Iron Quadrangle region of Brazil. The outcome was sleep quality, evaluated by the Pittsburgh Sleep Quality Index. Vitamin D (25-hydroxyvitamin D) concentrations were determined by indirect electrochemiluminescence and a deficiency was classified as 25(OH)D < 20 ng/mL. To assess sunlight, the average daily sunlight exposure was calculated and was classified as insufficient when less than 30 min/d. Multivariate logistic analysis was used to estimate the association between vitamin D and sleep quality. A directed acyclic graph was used to select minimal and sufficient sets of adjustment variables for confounding from the backdoor criterion. RESULTS: In a total of 1709 individuals evaluated, the prevalence of vitamin D deficiency was 19.8% (95% CI, 15.5-24.9%), and the prevalence of poor sleep quality was 52.5% (95% CI, 48.6-56.4%). In multivariate analysis, vitamin D was not associated with poor sleep quality in individuals with sufficient sunlight. Moreover, in individuals with insufficient sunlight, vitamin D deficiency was associated with poor sleep quality (odds ratio [OR], 2.02; 95% CI, 1.10-3.71). Furthermore, each 1-ng/mL increase in vitamin D levels reduced the chance of poor sleep quality by 4.2% (OR, 0.96; 95% CI, 0.92-0.99). CONCLUSIONS: Vitamin D deficiency was associated with poor sleep quality in individuals with insufficient exposure to sunlight.


Asunto(s)
COVID-19 , Deficiencia de Vitamina D , Adulto , Humanos , Luz Solar , Brasil/epidemiología , Calidad del Sueño , Estudios Transversales , Pandemias , COVID-19/complicaciones , Deficiencia de Vitamina D/epidemiología , Deficiencia de Vitamina D/complicaciones , Calcifediol , Vitaminas
9.
Nat Prod Res ; : 1-10, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36787159

RESUMEN

This study evaluated the responses of Carapichea ipecacuanha to sunlight stress-induced changes in the electron transport chain and its extended effects on alkaloid production (emetine and cephalin). The treatments consisted of: (i). 50, 70, and 90% shading (controls) and their respective exposure to full sunlight; besides, full sunlight (55 days of direct sun exposure). Photosynthetic pigments, chlorophyll a fluorescence transient, antioxidant enzymatic system, and quantification of cephalin and emetine were analyzed. Several changes in the Chl a fluorescence induction were observed, such as a decline in the quantum yield of the conversion of photochemical energy and photosynthetic performance and; an increase in emetine production of plants exposed to full sunlight. These results demonstrated that ipecac plants are extremely sensitive to full exposure to solar radiation, especially in periods with high temperatures, such as in summer, however with increment in emetine production.

10.
Environ Technol ; 44(1): 118-129, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34344269

RESUMEN

In the present work, composites with non-toxic metal oxides, such as TiO2 and ZnO, and a natural red clay (taua) reach in hematite were used in the photocatalytic degradation of Fenthion. The composite TiO2/Taua (0.5:1 wt. ratio) and pure TiO2 were prepared by sol-gel method while ZnO/Taua (0.5:1 wt. ratio) and pure ZnO were prepared by Pechini method. The materials were characterized by XRD, SEM, EDX, and DRS. The anatase phase was formed in both pure TiO2 and TiO2/Taua, while the hexagonal phase was formed in pure ZnO and ZnO/Taua. The bandgap energies for the two composites were narrowed compared to the respective pure oxides as consequence of the hematite (α-Fe2O3, Eg = 2.1 eV) in the red clay, reaching 2.1 eV for TiO2/Taua and 2.0 eV for ZnO/Taua, while the bandgap energies for pure TiO2 and ZnO were 3.2 and 3.0 eV, respectively. Fenthion was not degraded in the dark, but the concentration droped 20% after 180 min under visible light irradiation without photocatalyst and 60% after 210 min in the presence of the pure red clay. Both TiO2/Taua and ZnO/Taua composites were also photocatalytic active to degrade Fenthion (λ > 420 nm), with degradation of 78% (in 180 min) and 85% (in 210 min) respectively. In the optimized conditions (pH 2, 100 mg L-1 of H2O2 and 30 mg L-1 of Fenthion), the ZnO/Taua composite was the most efficient, reaching 89% degradation in up to 30 min, with Fenthion sulfoxide as the degradation product.


Asunto(s)
Óxidos , Óxido de Zinc , Arcilla , Peróxido de Hidrógeno , Luz
11.
Mult Scler ; 29(3): 343-351, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36250508

RESUMEN

BACKGROUND: Multiple sclerosis risk has been shown to have seasonal variations that are more pronounced in higher latitudes. However, this phenomenon has not been adequately studied near the Equator. OBJECTIVE: To explore the risk of multiple sclerosis associated with month, season of birth, and sunlight exposure variables in Colombia. METHODS: In this case-control study, 668 multiple sclerosis cases were matched to 2672 controls by sex and age. Association of multiple sclerosis with each month/season of birth and sunlight exposure variables was estimated with multilevel mixed-effects logistic regression and ecological regression models, respectively. Seasonality in the births of multiple sclerosis was assessed with a non-parametric seasonality test. RESULTS: We found a higher probability of multiple sclerosis in September (0.25; 95% confidence interval (CI) = 0.21-0.31) and lower in March (0.15; 95% CI = 0.10-0.18), which turned non-significant after a multiple comparisons test. Sunlight exposure variables had no significant effect on the risk of MS, and the tests of seasonality in the births of MS did not show significant results. CONCLUSION: Our results show no seasonality in the risk of multiple sclerosis near the Equator, supporting the hypothesis that this phenomenon is latitude dependent.


Asunto(s)
Esclerosis Múltiple , Humanos , Estudios de Casos y Controles , Estaciones del Año
12.
Rev. bras. entomol ; Rev. bras. entomol;67(3): e20220111, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1521736

RESUMEN

ABSTRACT Tropical forests are three-dimensional with the presence of numerous micro-environments formed by horizontal and vertical gradients. Such micro-environments can affect the nesting preference of organisms, including the trap-nesting Hymenoptera. Bees and wasps are key elements in ecosystems and are considered as sensitive to environmental changes, and trap-nests sampling methodology is widely used in their ecological and conservation studies. However, many uncertainties remain about nesting site preferences. From this perspective, our aim is to assess the diversity descriptors of trap-nesting Hymenoptera in different micro-environments. The sampling was conducted on three micro-environments (canopy, understory and treefall gaps) replicated on ten permanent plots within a Brazilian Atlantic forest hotspot. In each micro-environment, we installed trap-nest stations made by a set of twenty bamboo artificial nests. We found 762 brood cells from ten wasp and five bee species. The rarefaction curves indicate the lower species richness in understory stations, while treefall gaps and canopy stations were not significantly different. We analyzed abundance, mortality and parasitism rates using generalized linear models, but only abundance varies significantly among micro-environments. Our data indicates that trap-nesting Hymenoptera prefer to nest in micro-environments with higher exposure of sunlight. Canopy and treefall gap assemblages are consistently more abundant and diverse than understory probably due the higher temperature and lower humidity. On the other hand, mortality, parasitism rates, and the species composition were similar among environments. Our hypothesis is that the species composition was not affected as these species have a foraging range that encompasses nearby micro-environments.

13.
São Paulo med. j ; São Paulo med. j;141(4): e2022139, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1432448

RESUMEN

ABSTRACT BACKGROUND: The coronavirus disease (COVID-19) pandemic has adversely affected the health of the global population, with sleep quality being one of the affected parameters. OBJECTIVES: To evaluate sleep quality and its associated factors in adults during the COVID-19 pandemic in Brazil. DESIGN AND SETTING: A population-based cross-sectional serological survey of 1,762 adults in the Iron Quadrangle region of Brazil. METHODS: The Pittsburgh Sleep Quality Index was used to assess sleep quality. Sociodemographic variables, health conditions, health-related behaviors, anxiety, vitamin D levels, weight gain/loss, and pandemic characteristics were assessed using a structured questionnaire. Univariate and multivariate analyses using Poisson regression with robust variance were performed to identify factors associated with sleep quality. RESULTS: More than half of the participants reported poor sleep quality (52.5%). Multivariate analysis revealed that the factors associated with poor sleep quality included living alone (prevalence ratio [PR] = 1.34; 95% confidence interval [CI]: 1.04-1.73), anxiety disorder (PR = 1.32; 95% CI: 1.08-1.62), 5.0% weight loss (PR = 1.21; 95% CI: 1.02-1.44), 5.0% weight gain (PR = 1.27; 95% CI: 1.03-1.55), vitamin D deficiency (PR = 1.16; 95% CI: 1.01-1.35), and COVID-19 symptoms (PR = 1.29; 95% CI: 1.10-1.52). CONCLUSIONS: Our study revealed that more than half of the participants experienced poor sleep quality during the COVID-19 pandemic. Factors associated with poor sleep quality included vitamin D deficiency and weight changes related to the pandemic.

14.
HardwareX ; 11: e00302, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35509935

RESUMEN

The development and optimization of renewable energy systems are some of the most necessary topics to advance towards secure and sustainable energy models. Photovoltaic energy is one of those sustainable options that could contribute to the reduction of greenhouse gas emissions. The optimal angle of solar incidence producing the highest absorption in a day is an important parameter to install photovoltaic systems. This value is often estimated using simulation models based on geographic location; however, those models ignore the influence of nearby obstruction objects, albedo, and local weather conditions. Such a problem is addressed in this work by designing a system to estimate the optimum angle of solar incidence for the photovoltaic panels. The system is based on an arrangement of 33 measurement points spaced in arcs every 45 degrees in azimuth and every 22.5 degrees in elevation, which provides a wide range for analysis. The light captured by each optical fiber is transmitted to a flat array where the power is measured using a single RGB camera.

15.
New Phytol ; 235(5): 2022-2033, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35579884

RESUMEN

Plant litter decomposition is a key process for carbon (C) turnover in terrestrial ecosystems. Sunlight has been shown to cause and accelerate C release in semiarid ecosystems, yet the dose-response relationships for these effects have not been evaluated. We conducted a two-phase experiment where plant litter of three species was subjected to a broad range of cumulative solar radiation (CSR) exposures under field conditions. We then evaluated the relationships between CSR exposure and abiotic mass loss, litter quality and the subsequent biotic decomposition and microbial activity in litter. Dose-response relationships demonstrated that CSR exposure was modestly correlated with abiotic mass loss but highly significantly correlated with lignin degradation, saccharification, microbial activity and biotic decay of plant litter across all species. Moreover, a comparison of these dose-response relationships suggested that small reductions in litter lignin due to exposure to sunlight may have large consequences for biotic decay. These results provide strong support for a model that postulates a critical role for lignin photodegradation in the mechanism of photofacilitation and demonstrate that, under natural field conditions, biotic degradation of plant litter is linearly related with the dose of solar radiation received by the material before coming into contact with decomposer microorganisms.


Asunto(s)
Ecosistema , Exposición a la Radiación , Lignina/metabolismo , Fotólisis , Hojas de la Planta/metabolismo , Plantas/metabolismo
16.
Obes Surg ; 32(7): 2386-2396, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35513763

RESUMEN

BACKGROUND: Vitamin D deficiency is a common consequence of bariatric surgery (BS). However, few studies have evaluated influential factors and to date there are no studies investigating individual ultraviolet B (UVB) radiation levels in BS patients. This study aimed to evaluate vitamin D deficiency and its associated factors, including UVB radiation, in Roux-Y gastric bypass (RYGB) patients. METHODS: This study included 104 adults (90.4% female) at least 5 years after RYGB. Patients underwent surgery in private hospitals (Private; n = 47) or in two public hospitals, one with ongoing outpatient care (Active; n = 17), and the other with discontinued service for BS (Discontinued; n = 40). 25-hydroxyvitamin D (25(OH)D) concentrations were analyzed by chemiluminescence, individual UVB radiation levels by dosimeter badges. Vitamin D intake, anthropometric, skin phototype, sociodemographic and lifestyle patterns were also assessed. RESULTS: Mean age was 49.6 ± 9.1 years and post-operative period 8.7 ± 2.2 years. The prevalence of 25(OH)D deficiency and insufficiency was 25.0% and 51.9% respectively. 25(OH)D concentration differed among the hospitals (private = 26.2 ± 8.5; active = 28.7 ± 11.4; discontinued = 23.5 ± 6.5 ng/mL; p = 0.038). A total of 26.2% of the variance observed in 25(OH)D concentrations was explained by daily UVB radiation levels (ß = 0.224; p = 0.032) and vitamin D intake (ß = 0.431; p < 0.001), controlling for age and BMI. CONCLUSION: A quarter of the evaluated patients presented vitamin D deficiency, which was associated with the discontinuation of the health care, higher BMI, lower vitamin D intake, and lower individual UVB radiation levels.


Asunto(s)
Cirugía Bariátrica , Obesidad Mórbida , Deficiencia de Vitamina D , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/cirugía , Vitamina D , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/epidemiología
17.
Insects ; 13(2)2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35206715

RESUMEN

With the aim of identifying key factors that determine oviposition decisions by Anastrepha obliqua for management purposes, we conducted a behavioral study under natural/semi-natural field conditions to identify where exactly in the fruit (upper, middle, or lower sections) females preferred to lay eggs in a highly susceptible mango cultivar ("Criollo"), and whether sunlight incidence and fruit chemical compounds influenced oviposition site selection by this pestiferous fly. Females oviposited in shaded, upper fruit sections where pulp had higher total carbohydrate concentrations but similar total protein, lipid, and polyphenol concentrations than non-oviposited sections. Peel had higher overall nutrient and mangiferin/quercetin-3-D-galactoside (polyphenols) concentrations. An untargeted metabolomic analysis of oviposited and non-oviposited fruit sections identified abscisic acid (ABA) and dihydrophaseic acid glucoside, a by-product of ABA catabolism, as potential chemical markers that could play a role in fruit acceptance behaviors by female flies. We conclude that females preferentially oviposit in fruit sections with optimal chemical and environmental conditions for larval development: more carbohydrates and antioxidants such as mangiferin and ferulic acid and lesser sunlight exposure to avoid lethal egg/larval desiccation/overheating. We make specific recommendations for A. obliqua management based on female host selection behavior, a tree pruning scheme exposing fruit to direct sunlight, application of a host marking pheromone, and the use of egg sinks in the orchard.

18.
J. Anim. Behav. Biometeorol ; 10(1): 2201, jan. 2022. graf, tab
Artículo en Inglés | VETINDEX | ID: biblio-1438134

RESUMEN

This study aimed to investigate the climatological impacts of air temperature, sunshine duration, and rain precipitation, in a moderate climate, on the reproductive performance of Romanov sheep in the continental part of Croatia, during two consecutive years (2019-2020). Our study included 549 matings with 520 successful conceptions at 5 Romanov sheep farms, and the fertility rate was 94.72%. The percentage of lambs delivered in winter was 53.27% (n = 277), in spring 20.19% (n = 105), in summer 14.23% (n = 74) and 12.31% in autumn (n = 64). According to percentile ranks and classification ratings, thermal conditions have been described as very warm (during 2019-2020), while precipitation conditions, expressed in percentiles, were wet (during 2019) but dry (during 2020) for this region. The peak of sexual activity was from mid-August until October in 2019 and from the end of August to November in 2020 for Romanov sheep in northwestern (NW) Croatia. A Kruskal-Wallis test showed a statistically significant difference in the number of pregnant ewes during the different mating seasons in the year (p < 0.001). Therefore, we can assume that air temperature, precipitation volume, and sunshine duration during the different seasons could impact the reproductive performance of Romanov sheep in a moderate climate.(AU)


Asunto(s)
Animales , Femenino , Preñez/fisiología , Ovinos/fisiología , Fenómenos Fisiológicos Reproductivos , Croacia , Efectos del Clima , Meteorología
19.
J. Anim. Behav. Biometeorol ; 10(1): 1-6, jan. 2022. graf, ilus, tab
Artículo en Inglés | VETINDEX | ID: biblio-1484118

RESUMEN

This study aimed to investigate the climatological impacts of air temperature, sunshine duration, and rain precipitation, in a moderate climate, on the reproductive performance of Romanov sheep in the continental part of Croatia, during two consecutive years (2019-2020). Our study included 549 matings with 520 successful conceptions at 5 Romanov sheep farms, and the fertility rate was 94.72%. The percentage of lambs delivered in winter was 53.27% (n = 277), in spring 20.19% (n = 105), in summer 14.23% (n = 74) and 12.31% in autumn (n = 64). According to percentile ranks and classification ratings, thermal conditions have been described as very warm (during 2019-2020), while precipitation conditions, expressed in percentiles, were wet (during 2019) but dry (during 2020) for this region. The peak of sexual activity was from mid-August until October in 2019 and from the end of August to November in 2020 for Romanov sheep in northwestern (NW) Croatia. A Kruskal-Wallis test showed a statistically significant difference in the number of pregnant ewes during the different mating seasons in the year (p < 0.001). Therefore, we can assume that air temperature, precipitation volume, and sunshine duration during the different seasons could impact the reproductive performance of Romanov sheep in a moderate climate.


Asunto(s)
Animales , Lluvia , Conducta Sexual Animal , Insolación/veterinaria , Cambio Climático , Ovinos
20.
Braz. J. Biol. ; 82: 1-6, 2022. graf, tab
Artículo en Inglés | VETINDEX | ID: vti-32914

RESUMEN

Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae) trees have a wide distribution in the Cerrado, and it is protected by federal laws. The need to monitor and understand pest damage to crops and forests is a major motivation for the study of population distribution. The mites (Acari) population distributions on C. brasiliense are unknown. We studied seasonal mite population distribution and their ecological indices on C. brasiliense trees in Cerrado areas during three years. Greatest number of Agistemus sp. (Stigmaeidae), Histiostoma sp. (Histiostomidae), Proctolaelaps sp. (Ascidae), and diversity and species richness on leaves of C. brasiliense occurred in the autumn; Tetranychus sp.1 (Tetranychidae) on leaves in the autumn and winter; Histiostoma sp., and Proctolaelaps sp. in fruits in the summer. No significant effect of season was observed in the abundance of Eutetranychus sp., Tetranychus sp.2 (Tetranychidae) and Acaridae. The populations of Acaridae, Eutetranychus sp., Proctolaelaps sp. and Tetranychus sp.1 negatively correlated with temperature. Proctolaelaps sp. and Tetranychus sp.1 correlated negatively with rainfall and Eutetranychus sp. and Proctolaelaps sp. positively with sunlight. The period with low rainfall and relative humidity increases the phytophagous mites and their predators, especially Agistemus sp.. The Tetranychus sp. and Histiostoma sp. species may become pests in C. brasiliense in the Cerrado domain.(AU)


As árvores Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae) têm ampla distribuição no Cerrado e são protegidas por leis federais. A necessidade de monitorar e entender os danos causados pelas pragas às culturas e florestas é uma das motivações para o estudo da distribuição populacional que para ácaros (Acari) em C. brasiliense é desconhecida. A distribuição sazonal de populações de ácaros e seus índices ecológicos em C. brasiliense em áreas de Cerrado foram estudados durante três anos. Maior número de Agistemus sp. (Stigmaeidae), Histiostoma sp.(Histiostomidae), Proctolaelaps sp. (Ascidae) e diversidade e riqueza de espécies nas folhas de C. brasiliense ocorreram no outono; Tetranychus sp.1 (Tetranychidae) no outono e inverno; Histiostoma sp. e Proctolaelaps sp. em frutos ocorreram no verão. Não foram observados efeitos das estações na abundância de Eutetranychus sp., Tetranychus sp.2 (Tetranychidae) e Acaridae. As populações de Acaridae, Eutetranychus sp., Proctolaelaps sp. e Tetranychus sp.1 correlacionaram-se negativamente com a temperatura. Correlações negativas foram observadas entre chuva e Proctolaelaps sp. e Tetranychus sp.1 e positivas entre luz solar e Eutetranychus sp. e Proctolaelaps sp.. Baixa pluviosidade e umidade relativa do ar aumentaram os ácaros fitófagos e seus predadores, principalmente Agistemus sp.. As espécies Tetranychus sp. e Histiostoma sp. podem se tornar pragas em C. brasiliense no domínio do Cerrado.(AU)


Asunto(s)
Ericales/parasitología , Infestaciones por Ácaros/diagnóstico , Estaciones del Año
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