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1.
Sci Total Environ ; 803: 150010, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34487897

RESUMO

This study investigates the impact of aerosol liquid water content (ALWC) and related factors, i.e., relative humidity (RH), aerosol mass concentration (PM2.5), and aerosol hygroscopicity, on aerosol optical properties, based on field measurements made in the Pearl River Delta (PRD) region of China at the surface (1 November 2019 to 21 January 2020) and in the upper boundary layer (the 532-m Guangzhou tower from 1 February to 21 March 2020). In general, temporal variations in the ambient aerosol backscattering coefficient (ßp) and ALWC followed each other. However, the surface ßp and 532-m ßp had generally opposite diurnal variation patterns, caused by dramatic differences in PM2.5 and ambient RH between the surface and the upper boundary layer. The ambient 532-m RH was systematically higher than the surface RH, with the latter having a much pronounced diurnal cycle than the former. The surface PM2.5 concentration was systematically higher than the PM2.5 concentration at 532 m, and their diurnal cycle patterns were overall opposite. These dramatic differences reveal that the atmospheric variables, i.e., ambient RH and the PM2.5 concentration in the upper boundary layer, cannot be directly represented by the same variables at the surface. Vertical variability should be considered. Clear differences in the sensitivities of aerosol light scattering to ambient RH, PM2.5, and aerosol hygroscopicity between the two levels were found and examined. Aerosol chemical composition played a minor role in causing the differences between the two levels. In particular, ßp was more sensitive to PM2.5 at the surface level but more to the ambient RH in the upper boundary layer. The larger contribution of aerosol loading to the variability in ßp at the surface implies that local emission controls can decrease ßp and further improve atmospheric visibility effectively at the surface during winter in the PRD region.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Umidade , Material Particulado/análise , Molhabilidade
2.
J Colloid Interface Sci ; 607(Pt 1): 367-377, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34509111

RESUMO

Harmless and breathable flexible humidity sensor has important applications in continuous and real-time detection of human physiological activities. In this work, with hydrophobic poly (vinylidene fluoride) (PVDF) membrane as both the template and substrate and cetyltrimethylammonium bromide as a structure regulator, polyaniline (PANI) was unilaterally deposited on a PVDF microporous membrane to facilely fabricate a single-sided integrated flexible humidity sensor (IFHS). Such IFHS is featured with unique micro/nano structure and good air permeability. Moreover, it exhibits good humidity sensing properties at room temperature including fast response, small hysteresis and stable response even under bending deformation. The flexible sensor could realize non-contact monitoring of human respiration and speaking activities. Unilateral deposition of PANI and good breathability of IFHS avoids direct contact between PANI and human skin, thus averting harms to human and minimizing the deterioration of humidity sensing properties of PANI layer. The simple method is universal to the preparation of single-sided, integrated, breathable, nontoxic and fast response wearable humidity sensors based on PANI and hydrophobic microporous polymer membranes, offering useful references for the construction of advanced flexible sensors.


Assuntos
Nanoestruturas , Dispositivos Eletrônicos Vestíveis , Compostos de Anilina , Humanos , Umidade , Polivinil , Compostos de Vinila
3.
J Colloid Interface Sci ; 607(Pt 2): 2010-2018, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34798709

RESUMO

The development of high-performance humidity sensors is of great significance to explore their practical applications in the fields of environment, energy saving and safety monitoring. Herein, a flexible, non-contact and multifunctional humidity sensor based on two-dimensional Co-metal organic frameworks (Co-MOF) nanosheets is proposed, which is fabricated by simple bottom-up synthesis method. Furthermore, environmentally friendly, renewable and abundant biomass phytic acid (PA) is modified on the surface of Co-MOF nanosheets, which releases free protons being capable of etching the framework of MOF to improve the hydrophilicity and conductivity of MOF. Compared with Co-MOF-based sensor, the Co-MOF@PA-based sensor exhibits significantly enhanced sensitivity and broadened response range within 23-95% relative humidity (RH). The humidity sensor has an excellent humidity sensing response over 2 × 103. The Co-MOF@PA-based sensor shows good flexibility and humidity sensing properties, endowing it with multifunctional applications in real-time facial respiration monitoring, skin humidity perception, cosmetic moisturizing evaluation and fruit freshness testing. Four respiration patterns, including slow breath, deep breath, normal breath and fast breath are wirelessly monitored in real time by Co-MOF@PA-based sensor and recorded by mobile phone software. The research work presents potential applications in human-machine interactions (HMI) devices in future.


Assuntos
Estruturas Metalorgânicas , Humanos , Umidade , Interações Hidrofóbicas e Hidrofílicas , Ácido Fítico
4.
Sci Total Environ ; 802: 149804, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34455269

RESUMO

Totally 1160 adults living in single-family houses in Sweden participated in a questionnaire survey on subjective indoor air quality (SIAQ). Inspectors investigated the dwellings and performed home measurements (mean indoor temperature 21.4 °C, mean indoor air humidity 34.2%, mean indoor air exchange rate 0.36 ac/h and mean moisture load indoor 1.7 g/m3). Totally 15.5% perceived draught, 28.0% perceived too high room temperature, 42.4% unstable room temperature, 36.8% too low room temperature, 19.6% stuffy air, 19.8% dry air and 29.9% dust or dirt. Measured room temperature was related to perception of room temperature. Higher relative air humidity was related to perceived unstable room temperature (OR = 1.70) and too low room temperature (OR = 1.96). Higher absolute air humidity was related to too high room temperature (OR = 1.21), unstable room temperature (OR = 1.34) and too low room temperature (OR = 1.35). Higher measured relative humidity, absolute air humidity and moisture load were all associated with stuffy air and unpleasant odor (OR = 1.45-1.97). Higher air exchange rate was related to less perceived unstable room temperature (OR = 0.93). Higher U value was related to draught (OR = 1.17), too low room temperature (OR = 1.09), unpleasant odor (OR = 1.12) and dust and dirt (OR = 1.07). New concrete slab foundation was related to less stuffy air (OR = 0.39) (vs. basement). Damp foundation was associated with more stuffy air (OR = 1.44) and unpleasant odor (OR = 1.61). Window pane condensation was related to stuffy air (OR = 1.88). Moldy odor reported by inspector was related to stuffy air (OR = 1.73). Observed mold in the attic was associated with more stuffy air and unpleasant odor. In conclusion, complaints of room temperature can indicate poor thermal environment. Higher air exchange rate can create a more stable thermal sensation. Excess indoor humidity, lower degree of thermal insulation, presence of window pane condensation and indoor dampness/mold can impair SIAQ. Higher ventilation and concrete slab foundation with underlying thermal insulation can improve SIAQ.


Assuntos
Poluição do Ar em Ambientes Fechados , Adulto , Poluição do Ar em Ambientes Fechados/análise , Humanos , Umidade , Suécia , Temperatura , Ventilação
5.
Food Chem ; 369: 130946, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469840

RESUMO

Relative humidity (RH) during conservation and the chemical composition of epicuticular wax layer are factors that determine fruit quality and weight loss. This study investigates the influence of RH on the epicuticular wax metabolism during citrus fruit storage, and how it is affected by abscisic acid (ABA). Low RH conditions increased alcohols and fatty acids abundance, mainly due to accumulation of docosanol and lignoceric and cerotic acids. Low RH also decreased terpenoids and nonacosane and hentriacontane contents, the most abundant alkanes. Consequently, the alkane/terpenoid ratio was decreased concomitantly with fruit weight loss and cuticle permeability increments. ABA treatment differently mediated wax compositional changes at high or low RH. At low RH, ABA attenuated the increase in fatty acids and enhanced the decrease in alcohols and the accumulation of terpenoids, mainly affecting lignoceric and cerotic acids, docosanol, α-amyrin, sitosterol, friedelin and friedelanone contents. These trends were inversed under high RH conditions.


Assuntos
Citrus sinensis , Frutas , Ácido Abscísico , Umidade , Triterpenos Pentacíclicos , Ceras
6.
Meat Sci ; 183: 108659, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34428606

RESUMO

The objective of this study was to evaluate the effect of aging period (0, 3, 6 or 9 weeks), aging temperature (2 versus 6 °C at 75% relative humidity, experiment 1) and relative humidity (70 versus 90% at 2 °C, experiment 2) on the sensory traits, oxidative stability and proteolysis of Belgian Blue beef. For each experiment, eight loins (M. longissimus thoracis et lumborum) from four animals (left and right side) were assigned to one of the two treatments (n = 4). Results showed no further tenderization after three weeks of aging, whereas metmyoglobin formation and lipid oxidation increased until nine weeks of aging (P < 0.05). During the nine weeks of aging, atypical flavor, odor and flavor intensity was affected (P < 0.05). This was accompanied by an increase of small peptides and other nitrogenous compounds. Aging temperature and relative humidity had only a very limited effect on the quality traits.


Assuntos
Manipulação de Alimentos/métodos , Carne Vermelha/análise , Animais , Bovinos , Feminino , Humanos , Umidade , Metamioglobina/análise , Músculo Esquelético/química , Odorantes , Oxirredução , Resistência ao Cisalhamento , Paladar , Temperatura , Fatores de Tempo
7.
Food Chem ; 368: 130836, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34411862

RESUMO

The postharvest ripening stage is necessary for Torreya grandis (T. grandis) nuts to complete aromatic synthesis, which requires appropriate temperature and relative humidity (RH). Currently, scarce information is available regarding the changes in aroma profiles in T. grandis nuts and the relationship with their response to different environmental conditions. Therefore, the interaction of temperature (20 °C or 30 °C) and relative humidity (70% RH or 90% RH) was investigated on aromatic substances after harvest. The results showed that 56 aromatic components were detected by a gas chromatography-mass spectrometer (GC-MS) and mainly divided into five categories, among which terpenes were the most abundant (56.2-86.7%). Principal component analysis (PCA) showed that both temperature and humidity can affect the aroma composition, and terpenes were mainly influenced by humidity. Specifically, d-limonene occupied the largest proportion of terpenes (63.0-90.8%) and was significantly upregulated by high humidity.


Assuntos
Nozes , Taxaceae , Umidade , Odorantes , Temperatura
8.
Environ Health Prev Med ; 26(1): 109, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789160

RESUMO

BACKGROUND: For the reason that many studies have been inconclusive on the effect of humidity on respiratory disease, we examined the association between absolute humidity and respiratory disease mortality and quantified the mortality burden due to non-optimal absolute humidity in Guangzhou, China. METHODS: Daily respiratory disease mortality including total 42,440 deaths from 1 February 2013 to 31 December 2018 and meteorological data of the same period in Guangzhou City were collected. The distributed lag non-linear model was used to determine the optimal absolute humidity of death and discuss their non-linear lagged effects. Attributable fraction and population attributable mortality were calculated based on the optimal absolute humidity, defined as the minimum mortality absolute humidity. RESULTS: The association between absolute humidity and total respiratory disease mortality showed an M-shaped non-linear curve. In total, 21.57% (95% CI 14.20 ~ 27.75%) of respiratory disease mortality (9154 deaths) was attributable to non-optimum absolute humidity. The attributable fractions due to high absolute humidity were 13.49% (95% CI 9.56 ~ 16.98%), while mortality burden of low absolute humidity were 8.08% (95% CI 0.89 ~ 13.93%), respectively. Extreme dry and moist absolute humidity accounted for total respiratory disease mortality fraction of 0.87% (95% CI - 0.09 ~ 1.58%) and 0.91% (95% CI 0.25 ~ 1.39%), respectively. There was no significant gender and age difference in the burden of attributable risk due to absolute humidity. CONCLUSIONS: Our study showed that both high and low absolute humidity are responsible for considerable respiratory disease mortality burden, the component attributed to the high absolute humidity effect is greater. Our results may have important implications for the development of public health measures to reduce respiratory disease mortality.


Assuntos
Clima , Umidade/efeitos adversos , Doenças Respiratórias/mortalidade , China/epidemiologia , Cidades/epidemiologia , Humanos , Modelos Teóricos , Dinâmica não Linear , Sensibilidade e Especificidade
9.
Sci Rep ; 11(1): 22027, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34764317

RESUMO

Rising temperature levels during spring and summer are often argued to enable lifting of strict containment measures even in the absence of herd immunity. Despite broad scholarly interest in the relationship between weather and coronavirus spread, previous studies come to very mixed results. To contribute to this puzzle, the paper examines the impact of weather on the COVID-19 pandemic using a unique granular dataset of over 1.2 million daily observations covering over 3700 counties in nine countries for all seasons of 2020. Our results show that temperature and wind speed have a robust negative effect on virus spread after controlling for a range of potential confounding factors. These effects, however, are substantially larger during mealtimes, as well as in periods of high mobility and low containment, suggesting an important role for social behaviour.


Assuntos
COVID-19/epidemiologia , Humanos , Umidade , Pandemias , Fatores de Risco , SARS-CoV-2/isolamento & purificação , Estações do Ano , Comportamento Social , Temperatura , Tempo (Meteorologia) , Vento
10.
AAPS PharmSciTech ; 23(1): 1, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34791545

RESUMO

Dry powder inhalers (DPIs) are favorable devices for the delivery of dry formulations to the lungs; still, they largely fail to deliver higher doses of active pharmaceutical ingredient (API) to the lower airways. Addition of fine particles of excipient (fines) to the blend of API and carrier was shown to improve aerosolization performance. Lactose monohydrate is ubiquitous excipient used for this purpose. Lactose exists in a thermodynamically stable crystalline form; however, processes like milling, sieving, or even mixing may induce alteration of crystalline structure and introduce amorphous domains, which could further affect the physico-chemical properties of the material. Therefore, the aim of this work is a detailed characterization of two commercially available types of inhalation grade fine lactose powders (Inhalac 400 and Inhalac 500) prepared using different air-jet milling parameters, with a focus on impact of storage conditions on material properties. We found that the different milling parameters resulted in variable particle size distribution (PSD), and thus surface areas, variable initial amorphous content, cohesivity, flowability, and moisture sorption of materials. In addition, exposure of fine powders to higher humidity reduced the amorphous content present in the materials, but also affected agglomeration tendency and dispersion behavior of both powders. We believe the obtained findings to be important for the aerosolization performance of carrier-based DPIs containing fines and thus need to be duly considered during formulation development.


Assuntos
Química Farmacêutica , Lactose , Administração por Inalação , Aerossóis , Inaladores de Pó Seco , Umidade , Tamanho da Partícula , Pós , Propriedades de Superfície
11.
Sci Rep ; 11(1): 21812, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34750498

RESUMO

An estimation of the impact of climatic conditions-measured with an index that combines temperature and humidity, the IPTCC-on the hospitalizations and deaths attributed to SARS-CoV-2 is proposed. The present paper uses weekly data from 54 French administrative regions between March 23, 2020 and January 10, 2021. Firstly, a Granger causal analysis is developed and reveals that past values of the IPTCC contain information that allow for a better prediction of hospitalizations or deaths than that obtained without the IPTCC. Finally, a vector autoregressive model is estimated to evaluate the dynamic response of hospitalizations and deaths after an increase in the IPTCC. It is estimated that a 10-point increase in the IPTCC causes hospitalizations to rise by 2.9% (90% CI 0.7-5.0) one week after the increase, and by 4.1% (90% CI 2.1-6.4) and 4.4% (90% CI 2.5-6.3) in the two following weeks. Over ten weeks, the cumulative effect is estimated to reach 20.1%. Two weeks after the increase in the IPTCC, deaths are estimated to rise by 3.7% (90% CI 1.6-5.8). The cumulative effect from the second to the tenth weeks reaches 15.8%. The results are robust to the inclusion of air pollution indicators.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19/epidemiologia , COVID-19/mortalidade , Clima , Hospitalização/estatística & dados numéricos , SARS-CoV-2 , Algoritmos , Teorema de Bayes , Tomada de Decisões , França/epidemiologia , Hospitais , Humanos , Umidade , Infectologia , Reprodutibilidade dos Testes , Transtornos Respiratórios , Estações do Ano , Temperatura
12.
Sensors (Basel) ; 21(21)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34770624

RESUMO

This work describes the development of a capacitive-type sensor created from nanoporous anodic aluminium oxide (NP-AAO) prepared by the one-step anodization method conducted in potentiostatic mode and performed in a low-cost homemade system. A series of samples were prepared via an anodization campaign carried out on different acid electrolytes, in which the anodization parameters were adjusted to investigate the effect of pore size and porosity on the capacitive sensing performance. Two sensor test cases are investigated. The first case explores the use of highly uniform NP-AAO structures for humidity sensing applications while the second analyses the use of NP-AAO as a capacitive touch sensor for biological applications, namely, to detect the presence of small "objects" such as bacterial colonies of Escherichia Coli. A mathematical model based on equivalent electrical circuits was developed to evaluate the effect of humidity condensation (inside the pores) on the sensor capacitance and also to estimate the capacitance change of the sensor due to pore blocking by the presence of a certain number of bacterial microorganisms. Regarding the humidity sensing test cases, it was found that the sensitivity of the sensor fabricated in a phosphoric acid solution reaches up to 39 (pF/RH%), which is almost three times higher than the sensor fabricated in oxalic acid and about eight times higher than the sensor fabricated in sulfuric acid. Its improved sensitivity is explained in terms of the pore size effect on the mean free path and the loss of Brownian energy of the water vapour molecules. Concerning the touch sensing test case, it is demonstrated that the NP-AAO structures can be used as capacitive touch sensors because the magnitude of the capacitance change directly depends on the number of bacteria that cover the nanopores; the fraction of the electrode area activated by bacterial pore blocking is about 4.4% and 30.2% for B1 (E. Coli OD600nm = 0.1) and B2 (E. Coli OD600nm = 1) sensors, respectively.


Assuntos
Escherichia coli , Tato , Óxido de Alumínio , Eletrodos , Umidade
13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(5): 827-832, 2021 May 10.
Artigo em Chinês | MEDLINE | ID: mdl-34814474

RESUMO

Objective: To understand the influence and lag effect of meteorological factors on the incidence of hand, foot and mouth disease (HFMD) in Shijiazhuang. Methods: The daily incidence data of HFMD in Shijiazhuang during 2017-2019 were collected from Chinese Information System for Disease Control and Prevention. The hourly meteorological data were collected form meteorological stations of Shijiazhuang of Chinese meteorological data network. The distributed lag nonlinear model was built for statistical analysis by software R 3.6.2. Results: When the daily average temperature was 15-26 ℃, the risk of incidence of HFMD increased at lag 3-6 days. However, the risk was highest when the temperature was 25 ℃ at lag 3 days (RR=1.03,95%CI:1.00-1.06). When the daily average relative humidity was more than 80%, the risk of incidence of HFMD increased at lag 5-18 days. However, the risk was highest at lag 9 days (RR=1.04, 95%CI: 1.02-1.06).When the daily average air pressure ranged from 999 hPa to 1 007 hPa, the risk of incidence of HFMD increased at lag 5-8 days. However, the risk was highest at lag 6 days (RR=1.01, 95%CI: 1.00-1.02).When the daily average precipitation ranged from 15 to 32 mm, the risk of incidence of HFMD increased at lag 3-18 days. However, the risk was highest at lag 6 days (RR=1.11, 95%CI: 1.02-1.19). Conclusions: Meteorological factors increased the risk of incidence of HFMD such as higher daily average temperature (15-26 ℃), higher daily average humidity (>80%), lower daily average air pressure (999-1 007 hPa) and higher daily average precipitation (15-32 mm) in Shijiazhuang during 2017-2019. They were all correlated with the incidence of HFMD with certain lag days. It is suggested to use these meteorological indicators for the early warning of HFMD.


Assuntos
Doença de Mão, Pé e Boca , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Umidade , Incidência , Conceitos Meteorológicos , Temperatura
14.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(7): 1235-1239, 2021 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-34814537

RESUMO

Objective: To analyze the influence and related lag effects of meteorological factors on scrub typhus (ST) in southwestern Yunnan, to provide a reference for the corresponding prevention and treatment measures. Methods: Data on ST and meteorology in Yunnan province from 2007 to 2018 were collected. A distributed lag nonlinear model was conducted to study the cumulative lag effects of temperature, relative humidity, and rainfall on ST. Results: From 2007-2018, a total of 19 975 ST cases were reported in southwestern Yunnan. Weekly mean temperature, mean relative humidity, and the risk of ST all showed J-shaped curves. The cumulative risk of ST increased with mean temperature >23 ℃, mean relative humidity >80%, and cumulative rainfall between 20 and 60 mm or over 100 mm, weekly. Taking the median value as the reference, higher temperature (22.27 ℃, 23.45 ℃), relative humidity (80.14%, 84.38%) and rainfall (37.17 mm, 74.42 mm) all increased the risk of disease while lower temperature (11.22 ℃,14.83 ℃), relative humidity (53.18%,65.36%) and rainfall (0.00 mm,0.55 mm) showed opposite effects. The temperature-lag effect lasted for 10 and 16 weeks, respectively, with ST's risk the highest during the week of exposure. Humidity-lag effects usually last for 10 and 17 weeks. The lag effect of rainfall lasted for 25 weeks, while the disease's risk was the highest in the 4th week. Conclusion: Factors as temperature, relative humidity, and precipitation showed nonlinear and lag effects on ST. High temperature, high relative humidity, and an appropriate amount of rainfalls increase the risk of ST. The authorities of public health should implement effective prevention and control measures according to meteorological conditions.


Assuntos
Tifo por Ácaros , China/epidemiologia , Humanos , Umidade , Incidência , Conceitos Meteorológicos , Tifo por Ácaros/epidemiologia
15.
Geospat Health ; 16(2)2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34726033

RESUMO

The tropical climate of Thailand encourages very high mosquito densities in certain areas and is ideal for dengue transmission, especially in the southern region where the province Nakhon Si Thammarat is located. It has the longest dengue fever transmission duration that is affected by some important climate predictors, such as rainfall, number of rainy days, temperature and humidity. We aimed to explore the relationship between weather variables and dengue and to analyse transmission hotspots and coldspots at the district-level. Poisson probability distribution of the generalized linear model (GLM) was used to examine the association between the monthly weather variable data and the reported number of dengue cases from January 2002 to December 2018 and geographic information system (GIS) for dengue hotspot analysis. Results showed a significant association between the environmental variables and dengue incidence when comparing the seasons. Temperature, sea-level pressure and wind speed had the highest coefficients, i.e. ß=0.17, ß= -0.12 and ß= -0.11 (P<0.001), respectively. The risk of dengue incidence occurring during the rainy season was almost twice as high as that during monsoon. Statistically significant spatial clusters of dengue cases were observed all through the province in different years. Nabon was identified as a hotspot, while Pak Phanang was a coldspot for dengue fever incidence, explained by the fact that the former is a rubber-plantation hub, while the agricultural plains of the latter lend themselves to the practice of pisciculture combined with rice farming. This information is imminently important for planning apt sustainable control measures for dengue epidemics.


Assuntos
Dengue , Animais , Clima , Dengue/epidemiologia , Umidade , Incidência , Tailândia/epidemiologia
16.
An Acad Bras Cienc ; 93(suppl 3): e20191278, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730738

RESUMO

We evaluated species richness, abundance, alpha diversity, and true diversity of Phlebotominae sand flies temporal changes in domiciles within the northern Argentina city of Corrientes. A total of 16 sampling nights were conducted seasonally throughout the years 2012-2014 through light traps supplemented with CO2. Meteorological and remote sensing environmental factors were used to assessed for vectors implications in disease transmission through Generalized Mixt Models. Lutzomyia longipalpis was the most abundant and common species, followed by Nyssomyia neivai and Migonemyia migonei. Lutzomyia longipalpis was more abundant in urban areas, Ny. neivai was associated with vegetation in periurban areas, both were found all sampling years with higher abundance during the rainy season. Positive association of Lu. longipalpis with precipitation and relative humidity and negative association with temperature were observed. Models showed humidity and vegetation as making effects on Lu. longipalpis abundance. Precipitation was significant for Mg. migonei models, with higher abundance in periurban and periurban-rural environments. For Ny. neivai models, relative humidity was the most important variable, followed by precipitation frequency. Our findings led to identify high risk areas and develop predictive models. These are useful for public health stakeholders giving tolls to optimized resources aim to prevent leshmaniasis transmission on the area.


Assuntos
Psychodidae , Animais , Argentina , Brasil , Cidades , Clima , Umidade , Insetos Vetores , Chuva , Temperatura
17.
J Nanosci Nanotechnol ; 21(6): 3269-3273, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34739781

RESUMO

In this work, to research the photoelectric responses to humidity using a semiconductor film, an ultraviolet (UV) light induced device has been investigated on SnO2 film at room temperature. Screen printing method was used to prepare SnO2 film on the Al2O3 substrate. The crystalline structure and morphology of SnO2 was characterized with XRD and FE-SEM. The UV light induced photoelectric responses of SnO2 to a constant humidity (20% RH) were evaluated firstly under four different bias voltages. At 2 V bias voltage, the photocurrent amplitude reaches 4.58 µA, which is higher than that of 0.2 V bias (0.27 µA). Then the photoelectric responses to different relative humidity conditions (20% RH, 40% RH and 60% RH) were tested. The results display that the photocurrent decreased while the relative humidity increased. To illustrate the anomaly current of SnO2 film at 60% RH, the darkcurrent to different relative humidity conditions (20% RH, 40% RH and 60% RH) were also tested. To make clear these results, corresponding probable illustration was proposed.


Assuntos
Raios Ultravioleta , Umidade , Compostos de Estanho
18.
Trop Anim Health Prod ; 53(6): 534, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34739597

RESUMO

This study aimed to investigate the effect of beta-casein genotypes (A1A2 and A2A2) in three different thermal comfort conditions on the adaptability of Sindhi cows and as a tool for selecting thermotolerant cattle. Twelve Sindhi cows were used in a completely randomized design in a 2 × 3 factorial arrangement, with six replicates, with two genotypes, and three thermal comfort conditions. The climatic variables were recorded, while black globe temperature, humidity index, and radiant heat load were calculated. We measured respiratory rate, surface temperature, and rectal temperature while the heat tolerance coefficient was calculated. Genotype had no significant effect (p > 0.05) on any of the parameters measured. However, there was a thermal comfort condition effect (p < 0.05) on rectal temperature, surface temperature, and thermal gradients. The respiratory rate and heat tolerance coefficient were not significantly affected (p > 0.05). Therefore, although the results indicate substantial adaptability of Sindhi cows under any thermal conditions, the tested genotypes should not be used as a tool for selecting thermotolerant Sindhi cows.


Assuntos
Caseínas , Termotolerância , Animais , Temperatura Corporal , Bovinos , Feminino , Temperatura Alta , Umidade , Lactação , Temperatura
19.
J Biomed Opt ; 27(7)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34725995

RESUMO

SIGNIFICANCE: Gas in scattering media absorption spectroscopy (GASMAS) enables noninvasive gas sensing in the body. It is developing as a tool for diagnosis and monitoring of respiratory conditions in neonates. Phantom models with relevant features to the clinical translation of GASMAS technology are necessary to understand technical challenges and potential applications of this technique. State-of-the-art phantoms designed for this purpose have focused on the optical properties and anthropomorphic geometry of the thorax, contributing to the source-detector placement, design, and optimization. Lung phantom mimicking the alveolar anatomy has not been included in the existent models due to the inherent complexity of the tissue. We present a simplified model that recreates inflated alveoli embedded in lung phantom. AIM: The goal of this study was to build a lung model with air-filled structures mimicking inflated alveoli surrounded by optical phantom with accurate optical properties (µa = 0.50 cm - 1 and µs'=5.4 cm-1) and physiological parameters [37°C and 100% relative humidity (RH)], and to control the air volume within the phantom to demonstrate the feasibility of GASMAS in sensing changes in pulmonary air volume. APPROACH: The lung model was built using a capillary structure with analogous size to alveolar units. Part of the capillaries were filled with liquid lung optical phantom to recreate scattering and absorption, whereas empty capillaries mimicked air filled alveoli. The capillary array was placed inside a custom-made chamber that maintained pulmonary temperature and RH. The geometry of the chamber permitted the placement of the laser head and detector of a GASMAS bench top system (MicroLab Dual O2 / H2O), to test the changes in volume of the lung model in transmittance geometry. RESULTS: The lung tissue model with air volume range from 6.89 × 10 - 7 m3 to 1.80 × 10 - 3 m3 was built. Two measurement sets, with 10 different capillary configurations each, were arranged to increase or decrease progressively (in steps of 3.93 × 10 - 8 m3) the air volume in the lung model. The respective GASMAS data acquisition was performed for both data sets. The maximum absorption signal was obtained for configurations with the highest number of air-filled capillaries and decreased progressively when the air spaces were replaced by capillaries filled with liquid optical phantom. Further studies are necessary to define the minimum and maximum volume of air that can be measured with GASMAS-based devices for different source-detector geometries. CONCLUSIONS: The optical properties and the structure of tissue from the respiratory zone have been modeled using a simplified capillary array immersed in a controlled environment chamber at pulmonary temperature and RH. The feasibility of measuring volume changes with GASMAS technique has been proven, stating a new possible application of GASMAS technology in respiratory treatment and diagnostics.


Assuntos
Pulmão , Oxigênio , Humanos , Umidade , Recém-Nascido , Pulmão/diagnóstico por imagem , Imagens de Fantasmas , Temperatura
20.
Sensors (Basel) ; 21(21)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34770253

RESUMO

Soil moisture measurement is very important for soil system monitoring. Compared to the traditional thermo-gravimetric technique, which is time-consuming and can be only performed in labs, the optic-fiber technique has unique advantages, such as small size, remote application in fields, fast response time and immunity to electromagnetic fields. In this paper, the soil moisture is measured by using a polymer optical fiber Bragg grating (POFBG) probe with a packaged dimension of 40 mm × 15 mm × 8 mm. Due to the intrinsic water-absorbing property of poly (methyl methacrylate) (PMMA), optical fiber Bragg gratings based on PMMA have been widely investigated for humidity measurement. Taking advantage of this, a sensor based on the POFBG is investigated to verify the soil condition. The POFBG is protectively integrated inside a stainless-steel package. A window is opened with a thin polypropylene mat as a filter, which allows the air to go through but prevents the soil from going inside to pollute the POFBG. The sensor probe is embedded in soils with different gravimetric soil moisture contents (SMCs) ranging from 0% to 40% and, then, insulated by polyethylene films to minimize the impact from the external environment, showing an average temperature cross sensitivity of -0.080 nm/°C. For a constant temperature, an exponential relationship between the Bragg wavelength and the SMC is obtained. For the SMCs between 8% and 24%, linear relationships are presented showing a temperature-corresponded sensitivity between 0.011 nm/% and 0.018 nm/%. The maximal sensitivity is calculated to be 0.018 nm/% at 20 °C, which is 28 times as high as that in the previous work. For the SMC over 24%, the sensor becomes insensitive because of humidity saturation in the cavity of the sensor probe. Though temperature cross sensitivity is problematic for SMC measurement, the influence could be eliminated by integrating another humidity-insensitive temperature sensor, such as a silica FBG temperature sensor.


Assuntos
Polimetil Metacrilato , Água , Umidade , Solo , Temperatura
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