Resumo Considerando as mudanças climáticas e o impacto das temperaturas elevadas na saúde humana, especialmente devido ao aquecimento global, são relevantes as ações de prevenção ao calor voltadas aos trabalhadores que laboram a céu aberto. Neste ensaio, são apresentados resultados de recentes pesquisas, bem como destacadas inovações tecnológicas para monitoramento do calor no Brasil. Também são expostas reflexões sobre o futuro do trabalho a céu aberto diante das mudanças climáticas. O trabalho a céu aberto é em geral caracterizado por atividades pesadas, que geram elevado calor metabólico. Contudo, são escassos os esforços no campo da Saúde e Segurança do Trabalho para a busca de alternativas que minimizem ou eliminem os efeitos do calor para os trabalhadores. Além disso, as alternativas de proteção dos trabalhadores são reduzidas. O Monitor IBUTG é apresentado como inovação tecnológica de monitoramento remoto do calor em ambiente a céu aberto. Apesar das medidas de controle previstas em lei para proteção dos trabalhadores submetidos ao calor, em razão do aquecimento global, serão necessários intervenções inovadoras e controles especiais da exposição ao calor nos ambientes externos. Portanto, é desejável maior empenho na produção de conhecimento com vistas a fomentar a elaboração ou o aprimoramento de políticas públicas. humana global ensaio pesquisas Brasil pesadas metabólico Contudo disso reduzidas externos Portanto públicas

Abstract Given the current climate change and high-temperature impact on human health, especially due to global warming, actions for heat prevention focused on outdoor workers are relevant. This essay presents the results of recent research and highlights technological innovations for heat monitoring in Brazil. Also, it reflects on the future of outdoor work given climate change. Outdoor work is generally characterized as heavy, leading to higher metabolic heat production. However, Occupational Safety and Health have made few efforts to find alternatives to minimize or eliminate heat impact on workers. Moreover, the worker’s protection alternatives are reduced. WBGT Monitor is presented as a technological innovation for remote heat monitoring in outdoor environments. Despite the control measures provided to workers subjected to heat, global warming demands innovative interventions and special exposure controls at outdoor workplaces. Thus, an increased commitment to knowledge production to elaborate or improve public policy is desirable. hightemperature high temperature health relevant Brazil Also heavy However Moreover worker s reduced environments workplaces Thus desirable

RESUMO A transmissão de infecções respiratórias tem importante impacto na saúde humana, sobretudo no atual contexto da pandemia de COVID-19. Neste trabalho, discute-se um purificador de ar que utiliza radiação ultravioleta-C (UVC) e filtro high efficiency particulate air (HEPA) como mecanismos para descontaminar ambientes internos com baixa circulação de ar. Para avaliar os parâmetros físico-químicos do equipamento e sua ação microbicida, foram determinados a irradiância produzida pela lâmpada, a vazão na entrada e saída do dispositivo, as alterações na concentração de ozônio e o potencial de descontaminação do equipamento para Staphylococcus aureus, Escherichia coli e Candida albicans. A dose total de radiação UVC que o ar recebe ao passar pelo equipamento foi de 801,4 μJ cm-2, o que representaria a inativação de até 80% de Sars-CoV-2 no ar. Além disso, a eficiência de filtração foi reduzida para cerca de 60% com a diminuição do tamanho da partícula para partículas com menos de 1 μm e manteve-se acima de 90% para MP2,5 e MP10. Nos testes microbiológicos, observou-se redução de 99,4, 99,9 e 99,5% para S. aureus, E. coli e C. albicans, respectivamente, em 11 minutos.

ABSTRACT The transmission of respiratory infections has an important role on human health, especially in the current context of the COVID-19 pandemic. In this work, we present the assessment of an air purifier that uses ultraviolet-C (UVC) radiation and a “High Efficiency Particulate Air” (HEPA) filter as mechanisms to decontaminate indoor environments with low air circulation. To assess the physicochemical and microbicidal characteristics of the equipment, the irradiance produced by the lamp, the flow rate at the entrance and exit of the device, possible changes in the ozone concentration and the equipment's decontamination potential for Staphylococcus aureus, Escherichia coli and Candida albicans. The total dose of UVC radiation that the air receives when passing through the equipment was 801.4 μJ cm-2, which would represent an inactivation of up to 80% of SARS-CoV-2 in the air. Furthermore, the filtration efficiency dropped with smaller particle diameter, and reduced to around 60% for particles with less than 1 μm and remained above 90% for PM2.5 and PM10. In microbiological tests, there was a reduction of 99.4%, 99.9% and 99.5% for S aureus, E. coli and C. albicans, respectively, in 11 minutes.

Abstract This study investigated the effects of low concentrations of sericin (≤ 1.5 wt%) in starch- poly(butylene-adipate-co-terephthalate) (PBAT) films. The films were produced by blown extrusion and mechanical, barrier and structural properties were determined. Films containing 1.0 and 1.5 wt% sericin showed higher tensile strength (6.41 and 6.59 MPa) and Young's modulus (90.88 and 132.71 MPa) compared with film without sericin (4.76 MPa and 18.64 MPa). When 0.5 wt% of sericin was used, the elongation was reduced by 62%. The addition of sericin in a concentration of 1.5% (w/w) decreased the water vapor permeability of films from 7.55 to 5.94 g (m s Pa)-1, likely due to the formation of a more homogeneous and compact matrix. Based on these results, a mechanism of action is proposed, whereby sericin acts at the interface of the polymers (starch and PBAT), reducing the interfacial tension and enhancing compatibility.

ABSTRACT Objective: To evaluate the prevalence of temporomandibular dysfunction (TMD) and its association with perceived stress and common mental disorder (CMD) in academic students. Methods: This is s transversal observational study conducted at Universidade de Minas Gerais, Divinópolis Unit, in health science courses. To investigate the prevalence of TMD, the anamnestic index by Fonseca was used. Stress was assessed by the perceived stress scale, translated and adapted for the Brazilian population in 2006. To track CMD, we used the Self-Reporting Questionnaire (SRQ-20). Data were analyzed using SPSS version 13.0, adopting a 5% significance level. Results: The prevalence of TMD in the sample was 71.9%, distributed as follows: Light TMD (50.0%), moderate (16.4%) and severe (5.5%), being more frequent among women (76.4%). Common mental disorders were present in 29.9% of participants. The average perceived stress was 30.9. Conclusion: The results of this study allow us to conclude that there is a statistically significant correlation between TMD and variables such as parafunctional habits, perceived stress and CMD. Level of Evidence II, Development of diagnostic criteria on consecutive patients (with universally applied reference "gold" standard).

Background : Apis mellifera stings are a problem for public health worldwide, particularly in Latin America due to the aggressiveness of its Africanized honeybees. Massive poisoning by A. mellifera venom (AmV) affects mainly the cardiovascular system, and several works have described its actions on heart muscle. Nevertheless, no work on the pharmacological action mechanisms of the AmV in isolated aorta has been reported. Thus, the present work aimed to investigate the actions of AmV and its main fractions, phospholipase A2 (PLA2) and melittin, on isolated aorta rings and a probable action mechanism. Results : AmV and the complex PLA2 + melittin (0.1-50 μg/mL) caused contraction in endothelium-containing aorta rings, but neither isolated PLA2 nor melittin were able to reproduce the effect. Endothelium removal did not change the maximum vasoconstrictor effect elicited by AmV. Ca2+-free medium, as well as treatment with phentolamine (5 μM), verapamil (10 μM), losartan (100 μM), and U-73122 (10 μM, a phospholipase C inhibitor), eliminated the AmV-induced contractile effects. Conclusions : In conclusion, AmV caused contractile effect in aorta rings probably through the involvement of voltage-operated calcium channels, AT1 and α-adrenergic receptors via the downstream activation of phospholipase C. The protein complex, PLA2 + melittin, was also able to induce vasoconstriction, whereas the isolated proteins were not.

The aim of this in vitro study was to compare the photoactivation effects of QTH (Quartz-Tungsten-Halogen) and LED (Light-Emitting Diode) on the SBS (Shear Bond Strength) of orthodontic brackets at different debond times. Seventy-two bovine lower incisors were randomly divided into two groups according to the photoactivation system used (QTH or LED). The enamel surfaces were conditioned with Transbond self-etching primer, and APC (Adhesive Pre-Coated) brackets were used in all specimens. Group I was cured with QTH for 20 s and Group II with LED for 10 s. Both groups were subdivided according to the different experimental times after bonding (immediately, 24 h and 7 days). The specimens were tested for SBS and the enamel surfaces were analyzed according to the Adhesive Remnant Index (ARI). The statistical analysis included the Tukey's test to evaluate the main effects of photoactivation and debond time on SBS. The Chi-square test was used to compare the ARI values found for each group, and no statistically significant difference was observed. The debond time of 7 days for QTH photoactivation showed statistically greater values of SBS when compared to the immediate and 24 h periods. There was no statistically significant difference between the QTH and LED groups immediately and after the 24 h period. In conclusion, bonding orthodontic brackets with LED photoactivation for 10 s is suggested because it requires a reduced clinical chair time.

O complexo serrano do Espinhaço Sul é ainda floristicamente desconhecido e a conservação destas serras está ameaçada em função de sua exclusiva riqueza mineral. A Serra do Condado, localizada no município de Serro, MG (18° 37' 30" S e 43° 22' 30" W) é um bom exemplo de como as atividades de mineração estão distantes da conservação destes ecossitemas e por tal razão o presente estudo teve como objetivo a caracterização florística e fitofisionômica desta serra. As campanhas de campo foram quinzenais e ocorreram entre os meses de maio/2006 a maio/2007. Foram coletados apenas os materiais botânicos em estágio fenológico reprodutivo. Os mesmos foram incorporados aos acervos dos herbários CESJ, RB e ESAL. O valor em área de cada fisionomia na constituição da paisagem foi feito através do software ArGis 9.0 e a similaridade florística entre as fisionomias foi realizada mediante cálculo do índice de Sørensen. Na área estudada foram encontradas Florestas Estacionais Semideciduais Montanas, Matas Ciliares, Brejos e Vegetação Arbustivo-Lenhosa sobre Canga. A floresta semidecídua montana corresponde a 80% da vegetação local, apresentando 426 espécies (391 exclusivas) distribuídas em 83 famílias. As famílias com maior número de espécies foram Fabaceae (40), Asteraceae (30) e Myrtaceae (30). A floresta ciliar é pouco representativa, cobrindo 5% da área florestada. Nessa formação foram encontradas 74 espécies (54 exclusivas) pertencentes a 28 famílias. As famílias mais representativas foram Fabaceae (sete), Piperaceae (quatro) e Annonaceae (três). Os brejos, devido a perturbações antrópicas, cobrem apenas 2% da área. Por fatores como a saturação hídrica constante essa fitofisionomia apresentou o maior número de espécies exclusivas, 18 das 19 encontradas, sendo Cyperaceae e Melastomataceae (cinco) as famílias mais ricas. A Vegetação arbustivo-lenhosa sobre canga cobre 13% da área. Nela foram encontradas 94 espécies (74 exclusivas), distribuídas em 29 famílias. Asteraceae (nove), Orchidaceae (sete) e Bromeliaceae (cinco) destacaram-se pela riqueza de espécies nessa fisionomia. A flora da Serra do Condado foi diferenciada entre seus hábitats (fitofisionomias), pois os valores obtidos para o índice de Sørensen foram inferiores a 10% em todas as comparações. Isso demonstra o quanto estudo florísticos são fundamentais para o conhecimento da vegetação de áreas extensas geograficamente e diversas biologicamente. A variedade de ambientes apresentados e a riqueza da flora associada às suas formações agregam valor de conservação e manutenção da flora dos complexos serranos do Espinhaço Sul de Minas Gerais.

Little is known about the flora of the Espinhaço Sul range. However, the environmental conservation of such complex has been threatened, mainly due to the potential mineral richness lying there. The aim of this study was to the floristic and physiognomy characterization of Serra do Condado, located in the Serro County, MG. Thus, fortnight field campaigns were carried out during the period of May/2006 to May/2007, in order to collect floristic material and to characterize the area. Furthermore, the value in area of each physiognomic in the constitution of the landscape was made through the software ArGis 9.0 and the floristic similarity among the observed physiognomic aspects, were tested by the Sørensen similarity index. Atlantic Semideciduos Montane Forests, Riparian Forests, Swamps and Woody Shrub Vegetation over "Canga" were found in the area. Semidecidual Forest corresponds to 80% of the local vegetation, presenting 426 species (391 exclusives) distributed in 83 families. The families that had the largest number of species were Fabaceae (40), Asteraceae (30) and Myrtaceae (30). Following came, Woody Shrub Vegetation over "Canga", covers 13% of the studied area, and in it were found 94 species (74 exclusives), distributed among 29 families. Asteraceae (9), Orchidaceae (7) e Bromeliaceae (5) were distinguished by their species abundance in this physiognomy. Riparian Forests are not so representative, constituting only 5% of the forested area. In this physiognomy, 74 species (54 exclusives) belonging to 28 families were found, of these, Fabaceae (7), Piperaceae (4) and Annonaceae (3) were the most representative ones. Due to anthropogenic disturbances, Swamps cover only 2% of the area. As it showed characteristics such as constant hydric saturation it had the highest proportion of exclusive found species, 18 out of 19, being Cyperaceae and Melastomataceae (5) the richest families. The flora found at Serra do Condado was differentiated in relation to their habitats (physiognomies), because the values obtained by the Sørensen index were less than 10% for all other comparisons. This shows how fundamental floristic studies are for knowing the vegetation of areas being both geographically extensive and biologically diverse. The great variety of environment presented and the flora richness associated to this formation aggregate conservation and maintenance value to the Espinhaço Sul range flora, Minas Gerais.

Com o objetivo de caracterizar as limitações nutricionais para a produção de matéria seca do mangarito [(Xanthosoma mafaffa (L.) Schott)], conduziu-se um experimento em casa de vegetação com amostras da camada de 0-20 cm de um Latossolo Vermelho Amarelo sob vegetação de cerrado, coletado no município de Montes Claros, MG. O cultivo foi realizado em vasos de 3 L de capacidade. O delineamento experimental foi inteiramente casualizado, em treze tratamentos, com três repetições. Os tratamentos foram baseados na técnica do elemento faltante (em que se omite a calagem e cada um dos macronutrientes e micronutrientes). A ordem decrescente dos tratamentos que mais afetaram a produção de matéria seca da parte aérea foi: -Calagem> -P > -S > testemunha > -B > -Calagem+Ca+Mg > -N > -K. A omissão de Ca, Mg, Zn e Cu não afetaram a produção de matéria seca da parte aérea. A ordem decrescente dos tratamentos que mais afetaram a produção de matéria seca de raízes foi: -B > -Mg > -Calagem+Ca+Mg > -K > -N > -Zn > -Calagem > -S > -Cu > -Ca > -Cu > -Ca > testemunha > -P.

The aim of this work was to characterize the nutritional limitations for dry matter production of Xanthosoma mafaffa (L.) Schott. The experiment was carried out in a greenhouse with 0-20 cm samples of a Oxisol under cerrado vegetation, collected at Montes Claros, Minas Gerais State, Brazil. The cultivation was conducted in 3 L pots. The experimental design was totally randomized with 13 treatments and three replications. Treatments were based on the missing element technique (with omission of liming and each one of the macro and micronutrients). The decreasing order of treatments that more influenced the aerial dry matter production was: -liming> -P > -S > test > -B > -liming+Ca+Mg > -N > -K. The omission of Ca, Mg, Zn and Cu did not influence the aerial dry matter production. The decreasing order of treatments that influenced the root dry matter production was: -B > - Mg > -liming+Ca+Mg > -K > -N > -Zn > -liming > -S > -Cu > -Ca > -Cu > -Ca > test > -P.

A cultura da melancia é uma atividade explorada regionalmente, sendo uma das mais importantes fontes de renda familiar de pequenos municípios do médio Paranapanema, onde mudanças significativas no processo produtivo são atualmente constatadas, passando de mão-de-obra intensiva para uso de tecnologias promissoras, como é o caso do manejo de plantas daninhas. Um experimento foi conduzido no município de Oscar Bressani (SP), em área de produção comercial, com objetivo de estudar a interferência de plantas daninhas, no cultivo da melancia, na safra 2002/2003. O delineamento experimental utilizado foi de blocos ao acaso com dez tratamentos e quatro repetições, representadas por parcelas com área útil de 18 m², contendo quatro plantas de melancia e infestação prevalecente das espécies Sidaspp, Brachiaria humidicola, Commelina benghalensise Portulaca oleracea. A infestação das plantas daninhas foi estimada através de amostragens aleatórias das parcelas utilizando-se quadro vazado de ferro com 0,5 m de lado. Os tratamentos constaram de testemunhas capinadas e sem capina e diferentes épocas de controle da infestação, de forma que a cultura foi mantida na presença ou ausência das plantas daninhas até 7; 14; 28; 56 e 63 dias após a sua emergência (DAE). A ocorrência do período inicial de convivência possível maior que o período final estabeleceu o Período Crítico de Prevenção da Interferência do 9º ao 13º dias (PCPI= 9-13 DAE). A redução média da produtividade em função da interferência das plantas daninhas durante todo o ciclo da melancia foi de 41,4%. As características diâmetro e espessura da casca dos frutos também foram influenciadas pela convivência com a infestação durante todo o ciclo com decréscimos, de 7,9% e 23,3%, respectivamente, em média, ao contrário do comprimento e diâmetro de ramas e do ºBrix da polpa dos frutos, onde não foram constatadas diferenças significativas.

Water melon crop is an agricultural activity explored regionally, representing one of the most important sources of family income in small cities of the Médio Paranapanema, São Paulo State, Brazil, where nowadays, significant changes in the yield process are verified, changing from intensive labor to the use of promising technologies, as weed management, for instance. An experiment was carried out at Oscar Bressane municipal district, São Paulo State, Brazil, to study the weed interference on watermelon cultivation, in 2002/2003. Statistical procedure was based on randomized blocks with ten treatments and four replications, represented by plots with useful area of 18 m², containing four water melon plants and infestation of Sidaspp, Brachiaria humidicola, Commelina benghalensisand Portulaca oleraceaspecies. Weed infestation was estimated through randomized samples from the plots, using an iron drained square with 0,5 m sides. Treatments consisted of checks with and without hand weeded and different periods of weeds control, so that, crop was sustained in weeds presence or absence up to 7; 14; 28; 56 and 63 days after emergency (DAE). Initial period occurrence of possible coexistence greater than the final period established the Critical Period of Interference Prevention from the 9th to the 13th days (CPIP = 9-13 DAE). The reduction in yield due to the weed interference during all water melon crop cycle was about 41,4%. The diameter and thickness of fruits peel were also influenced by the coexistence with weed infestation during all the crop cycle, with decreases of 7,9% and 23,3%, respectively, against the characteristics length and diameter of branch and ºBrix of fruits pulp, when significant differences were not observed.

Com o objetivo de estudar o efeito da calagem, mediante a elevação da saturação por bases, sobre o crescimento e a produção de flavonóides totais de fava-d'anta cultivada em um solo de Cerrado de Minas Gerais, foi conduzido um experimento no Instituto de Ciências Agrárias da Universidade Federal de Minas Gerais, no período de outubro/2003 a fevereiro/2004. O delineamento experimental utilizado foi inteiramente casualizado, sendo cinco valores de saturação por bases: 10 (saturação natural), 25; 40; 55 e 70%, com seis repetições. Os resultados obtidos mostraram que o aumento da saturação por bases diminuiu o crescimento e não influenciou o teor de flavonóides totais da fava-d'anta.

With the purpose of studying the effect of levels of base saturation upon the growth and total flavonoids production of Dimorphandra mollis cultivated on a soil originally under Savana of Minas Gerais State, Brazil, an experiment was conducted at the Universidade Federal de Minas Gerais, between October/2003 and February/2004. The experiment followed a completely randomized design with five values of base saturation (V%): 10 (natural saturation), 25; 40; 55 and 70%, and six replicates. The increase of base saturation led to a decrease of Dimorphandra mollis growth, and did not influence the total flavonoids plant concentration.