High Humidity Exposure Research Articles

Direct Measurement of the Diffusion Coefficient of Adhesives from Moisture Distribution in Adhesive Layers Using Near-Infrared Spectroscopy.

In this study, we used near-infrared spectroscopy to measure the moisture penetration in epoxy adhesives and investigated the difference in the diffusion coefficients between the bulk and the adhesive layer. Moisture diffusion was evaluated under 100% RH and water immersion conditions. First, the effects of the curing agents and additives on moisture diffusion in the bulk were gravimetrically evaluated using epoxy-coated quartz glass plates. Different diffusion behaviors were observed depending on the curing agent used. The presence of additives resulted in higher diffusion coefficients, whereas the overall moisture content was low. Next, the moisture distribution in the adhesive layer was visualized using a specimen sandwiched between the quartz glass plates, and the diffusion coefficient of the adhesive layer was calculated. The diffusion coefficient in the adhesive layer was larger than that in the bulk. For adhesives cured with hydrophobic diamine, the diffusion coefficient within the adhesive layer increased by approximately 1.5 times compared with that in the bulk, regardless of the exposure environment. The adhesive, composed of a resin, Dicyandiamide, and additives, showed a 2-fold increase in the diffusion coefficient under high-humidity exposure conditions but no significant change under the water immersion condition. Therefore, these results suggest that, for an accurate analysis of moisture distribution, it is important to measure the diffusion coefficient of the adhesive layer directly rather than using the diffusion coefficient of the material itself.

Sulfur vacancy-rich bismuth sulfide nanowire derived from CAU-17 for radioactive iodine capture in complex environments: Performance and intrinsic mechanisms

Effective capture and immobilization of volatile radioiodine from the off-gas of post-treatment plants is crucial for nuclear safety and public health, considering its long half-life, high toxicity, and environmental mobility. Herein, sulfur vacancy-rich Vs-Bi2S3@C nanocomposites were systematically synthesized via a one-step solvothermal vulcanization of CAU-17 precursor. Batch adsorption experiments demonstrated that the as-synthesized materials exhibited superior iodine adsorption capacity (1505.8 mg g−1 at 200 °C), fast equilibrium time (60 min), and high chemisorption ratio (91.7%), which might benefit from the nanowire structure and abundant sulfur vacancies of Bi2S3. Furthermore, Vs-Bi2S3@C composites exhibited excellent iodine capture performance in complex environments (high temperatures, high humidity and radiation exposure). Mechanistic investigations revealed that the I2 capture by fabricated materials primarily involved the chemical adsorption between Bi2S3 and I2 to form BiI3, and the interaction of I2 with electrons provided by sulfur vacancies to form polyiodide anions (I3-). The post-adsorbed iodine samples were successfully immobilized into commercial glass fractions in a stable form (BixOyI), exhibiting a normalized iodine leaching rate of 3.81 × 10−5 g m−2 d−1. Overall, our work offers a novel strategy for the design of adsorbent materials tailed for efficient capture and immobilization of volatile radioiodine.

Combinations of arginine and pullulan reveal the selective effect of stabilization mechanisms on different lyophilized proteins

The stability of lactate dehydrogenase (LDH) and β-galactosidase (β-gal), incorporated in arginine/pullulan (A/P) mixtures at various weight ratios by lyophilization, was determined. The physicochemical characteristics of various A/P mixtures were assessed. With decreasing A/P ratios, the glass transition temperature of the formulations increased. Furthermore, arginine crystallization due to high relative humidity (RH) exposure was prevented at an A/P weight ratio of 4/6 or less. When stored at 0 % RH / 60 °C for 4 weeks, arginine was superior to pullulan as stabilizer. During storage at 43 % RH / 30 ℃ for 4 weeks, the enzymatic activity of LDH was best retained at an A/P weight ratio of 2/8, while β-gal activity was relatively well-retained at A/P weight ratios of both 8/2 and 2/8. LDH seemed to be more prone to degradation in the rubbery state. In the glassy state, β-gal degraded faster than LDH. Solid-state nuclear magnetic resonance spectroscopy showed that (labeled) arginine experienced a different interaction in the two protein samples, reflecting a modulation of long-range correlations of the arginine side chain nitrogen atoms (Nε, Nη). In summary, LDH stabilization in the A/P matrix requires vitrification. Further stabilization difference between LDH and β-gal may be dependent on the interaction with arginine.

Effect of High Humidity Exposure to Wheat Starch Based High Conducting Flexible Polymer‐in‐Salt‐Electrolyte

AbstractPolymer‐in‐salt‐electrolytes (PISEs) are an important class of electrolytes as they carry the promise of faster and single ion transport. Unfortunately, due to unavailability of a suitable polymer host PISE has still not reached to commercial level. In the present work, using a novel synthesis protocol developed by the group, glutaraldehyde crosslinked wheat starch has been successfully modified with sodium iodide (NaI) to synthesize a flexible PISE membrane with desired electrochemical properties. Present paper reports the effect of crosslinker and exposure to high humidity ambience on electrochemical and morphological properties. It has been established that on exposure to higher humidity atmosphere starch‐based PISEs stabilize at lower resistance value, but with higher ion relaxation time, which indicates that effect of high humidity treatment is more on salt dissociation instead of assisting the ion transport. The studied materials have conductivity ≈0.01 S cm−1 range with ESW >2.5 V, ensuring its usability in electrochemical devices. The developed synthesis protocol does not require any complicated synthesis route and/or sophisticated instrument hence the overall process is economical also, adding up to its potentiality for energy device fabrication.

RETRACTED: An assessment of photovoltaic module degradation for life expectancy: A comprehensive review

Determining the life expectancy of a photovoltaic (PV) system involves many factors, including the assessment of photovoltaic module degradation. Degradation of PV modules is a normal process that develops over time as a result of a number of factors, including UV radiation exposure, thermal cycling, and weathering. The degradation rate, which is the percentage decline in module efficiency per year, is an often-used indicator for evaluating PV module deterioration. Depending on the type of module (crystalline silicon (c-Si), copper indium gallium selenide (CIGS) and cadmium telluride (CdTe) and the environment, degradation rates can vary greatly, although studies have indicated that most modules degrade at a rate of 0.5% to 1% per year. Additionally, the review focuses on developing PV technologies, like dye-sensitized solar cells (DSSCs), organic PVs (OPVs), and metal halideperovskite (MHP) solar cells, where relevant long-term degradation strategies have not yet entirely developed and the majority principles are not completely understood owing to their lower to medium technological maturity levels. Nonetheless, a thorough overview of the established stability issues related to every new photovoltaic technology is provided. There are a number of techniques that can be employed, including visual inspection, electrical performance testing, and infrared imaging, to evaluate the degradation of a PV module. Through the use of accelerated stress testing (AST), photovoltaic (PV) modules can be subjected to the consequences of years of operation in a fraction of the time. The goal of AST is to assess how well PV modules hold up over the long term in situations like high temperatures, humidity, and UV exposure. A PV module is put through a series of environmental circumstances that are more demanding than ordinary working conditions in order to perform an accelerated stress test on it. To calculate the module's rate of deterioration over time, data from an accelerated stress test can be used. This data is crucial for estimating the module's long-term performance and dependability as well as formulating plans to increase the lifespan of PV systems. Manufacturers, researchers, and designers of PV systems might benefit from using AST to assess the performance of PV modules in challenging environments and make sure they adhere to industry standards for toughness and dependability. Therefore, in this study, degradation factors, along with other parameters like the accelerated-stress tests linked to PV module degradation, to predict the life expectancy of various PV system especially matured PV systems, has been examined. This paper concludes by reviewing the lessons learnt from established photovoltaic technologies and discussing potential applications for these insights in the research and development of forthcoming technologies. Specifically, industry-standard accreditation tests must ultimately be passed by any developing PV technology, and advanced c-Si-based module warranties may be prolonged beyond the 25-year limit.

Prediction of the belt drive contamination status based on vibration analysis and artificial neural network

Belt drive contamination is considered one of the most common failure modes that could be developed in the belts due to harsh operation conditions, high humidity, and sunlight exposure, reducing the belt’s performance. If the belt failure has not been detected early, a sudden shutdown may happen, producing safety and economic consequences. However, most maintenance personnel use their senses of sight, hearing, smell, and touch to identify the cause of the problem while diagnosing a belt drive condition. Hence, this research involves developing an intelligent contamination status detection system based on vibration signal analysis for a pulley-belt rotating system. Time-domain signal analysis was employed to extract some suggestive features such as the root mean square, kurtosis, and skewness from the vibration data. An artificial neural network (ANN) model was built to detect the simulated different operating conditions. The vibration data was gathered with the help of two MEMS accelerometers (ADXL335) interfaced with an NI USB-6009 data acquisition device. A signal capture, analysis, and feature extraction system was developed using Matlab Simulink. The simulated operating conditions include clean, wet, and powder-contaminated belts. The results showed that the designed system could identify the pulley-belt operation conditions with 100% overall accuracy.

Synergistic Ion-Anchoring Passivation for Perovskite Solar Cells with Efficiency Exceeding 24% and Ultra-Ambient Stability.

The high-density defect states existing at the grain boundaries and heterojunction interfaces induce nonradiative charge recombination and ion migration processes within perovskite film, which seriously impair the device efficiency and stability. Here, we propose a novel synergistic ion-anchoring passivation (SIP) strategy for high-performance perovskite solar cells, by designing a multifunctional molecule to heal the charged defects via electrostatic interactions. The anion and cation species of the multifunctional molecule are rationally screened via high-throughput DFT simulation and experimental verification, which act as efficient surface passivation agents to heal the lead- and iodine-related defects. As a result, the defect-less perovskite films deliver encouraging device power conversion efficiency >24% with negligible hysteresis. A remarkable open-circuit voltage (Voc) of 1.17 V was obtained with a Voc deficit of 370 mV, featuring the outstanding defect-passivation capability of the SIP strategy. Moreover, the SIP-treated devices show exceptional ambient stability and maintain 70% of the initial efficiency after 150 h of high humidity exposure (relative humidity 70%-80%). Our results highlight the importance of the rational design of passivation agents to realize high-performance perovskite electronics.

Effect of epoxy resin addition on properties and corrosion behavior of sintered joints in power modules serviced offshore

Power modules applied in offshore applications are facing risks of corrosion failures on die-attach materials due to high humidity and H2S exposure. To investigate such corrosion behavior for sintered die-attach materials, we conducted a study with four groups of samples fabricated using copper and silver metal particles under different solvent systems. Such samples were firstly subjected to high-humidity-H2S conditions for 168 h to simulate the harsh offshore environment. After undergoing corrosion, the primary compounds formed were CuO/Cu2O and Ag2S through SEM, XRD, and XPS analysis. Notably, the incorporation of epoxy resin into sintered copper joints resulted in a remarkable reduction in corrosion and a substantial improvement in electrical conductivity after the reaction. In contrast, while the addition of epoxy did not evidently reduce corrosion in silver joints, it did lead to a significant increase in shear strength. Furthermore, to gain further insights into the effect of epoxy resin on corrosion behavior, electrochemical analysis, and molecular dynamics simulations were conducted. Finally, the mechanical reliability of the corroded copper and silver joints was evaluated through thermal shock tests. In summary, sintered copper joints exhibited better anti-corrosion behaviors than sintered silver under high humidity and H2S exposure, especially with the addition of epoxy resin. However, the corrosion products of sintered copper suffered from a sharp decrease in shear strength after thermal shock tests than sintered silver, which is probably due to the coefficient of thermal expansion mismatch.

Analysis of the Mechanical Properties of 3D-Printed Plastic Samples Subjected to Selected Degradation Effects.

The Fused Filament Fabrication (FFF) method is an additive technology that is used for the creation of prototypes within Rapid Prototyping (RP) as well as for the creation of final components in piece or small-series production. The possibility of using FFF technology in the creation of final products requires knowledge of the properties of the material and, at the same time, how these properties change due to degradation effects. In this study, the mechanical properties of the selected materials (PLA, PETG, ABS, and ASA) were tested in their non-degenerate state and after exposure of the samples to the selected degradation factors. For the analysis, which was carried out by the tensile test and the Shore D hardness test, samples of normalized shape were prepared. The effects of UV radiation, high temperature environments, high humidity environments, temperature cycles, and exposure to weather conditions were monitored. The parameters obtained from the tests (tensile strength and Shore D hardness) were statistically evaluated, and the influence of degradation factors on the properties of individual materials was assessed. The results showed that even between individual manufacturers of the same filament there are differences, both in the mechanical properties and in the behavior of the material after exposure to degradation effects.

Moisture-dependent room-temperature perovskite crystallization in vacuum flash-assisted solution processed intermediate phase films

We propose a straightforward intermediate-phase strategy to facilitate large-area crystallization of perovskite under room-temperature: preparing intermediate phase film with vacuum flash-assisted solution processing (VASP) method and performing controlled moisture-exposure subsequently. Moisture molecules penetrate into the whole intermediate film, remove residual solvent molecules, and trigger room-temperature crystallization of perovskite in a wide humidity range (25–80% RH), while negligible hydroxyl species are observed in the intermediate phase and resultant perovskite films. Without antisolvent, thermal-annealing and additive, high-humidity (80% RH) exposure of intermediate-phase film under room-temperature results in crystalline perovskite with a 8× increase in grain size and a 6× increase in photoluminescence lifetime, which is attributed to the homogenous and stable intermediate phase prepared by VASP and the synergistic effect of H 2 O and residual solvent molecules. Without antisolvent, thermal-annealing and additive, high-humidity (80% RH) exposure of intermediate-phase precursor film under room-temperature results in crystalline perovskite with a 8× increase in grain size and a 6× increase in photoluminescence lifetime. • The intermediate phase strategy applies in the wide range of 25–80% RH humidity. • Moisture exposure under room-temperature induces identical chemical transition. • Negligible hydroxyl species are observed in perovskite and its intermediate. • 80% RH exposure leads micron-size grains and microsecond fluorescence lifetime.

Dynamic moisture resistance of chemical and thermal modified plywood

ABSTRACT Time-dependent response of treated and untreated plywood to various modes of water exposure was studied. Treatments included 1.3-dimethylol-4.5-dihydroxyethyleneurea (DMDHEU) and phenol-formaldehyde (PF). The effect of thermal modification was also investigated. Water exposure regimes included: one-sided water spray, one-sided water soak, and high humidity – all for a duration of 192 h. Direct measurements of dimensional change were recorded, and digital image correlation (DIC) was used to continuously monitor two-dimensional swelling. Over 90% of thickness swell occurred during the first 24 h of liquid water exposure. Swelling was still progressing under 90% relative humidity exposure after 192 h. DMDHEU and PF were statistically equivalent and improved thickness swell by 64% and 60%, for water spray and water soak, respectively. Chemical treatment improved thickness swell by approximately 41% under high humidity. Thermal modification improved thickness swell by 36%, 28%, and 28% for water spray, water soak, and high humidity exposure after 192 h, respectively. DIC measurements during the first 3 h of exposure revealed the fastest rate of thickness swell occurred with one-sided water spray and the slowest rate during one-sided water soak. Overall, PF-treated plywood exhibited the best initial water resistance. After 24 h DMDHEU and PF were equally effective treatments.

Polysaccharides from fermented coix seed modulates circulating nitrogen and immune function by altering gut microbiota

Coix lachryma-jobi L. seed is an important food item in Asia with culinary and medicinal values. The effects of non-fermented coix seed (NFC), fermented coix seed with Lactobacillus plantarum NCU137 (FC) and polysaccharides from NFC, FC (FCP) on mice circulating nitrogen and immune disorder induced by high relative humidity (RH, 90 ± 2%) exposure were compared. All the treatments reduced circulating nitrogen (BUN and ammonia) might via increasing excretion of fecal nitrogen induced by altering gut microbiota. In comparison, FC and FCP restored erythrocyte morphology by promoting erythrocyte Na+/K+ ATPase activity more effectively, and immune function was modulated by reducing plasma IgM and IFN-γ levels, up-regulating IL-4 and IL-6 levels. Herein, these results indicated that FCP, as the main active ingredient in FC, modulated circulating nitrogen through altering gut microbiota, and restored immune homeostasis by regulating Th1/Th2 cytokines in mice receiving high RH exposure.

Early Detection of Toppling Susceptibility in Tulip Using Spectral Imaging

Forcing tulips is a process that mimics the conditions of winter and early spring in a controlled environment to make the tulips bloom months earlier than they would if grown in the open field. In this process, it is essential that the relative humidity in the growing environment is kept sufficiently low. Otherwise, there is an increased risk of the tulips losing solidity and eventually toppling over. Since maintaining this lower humidity demands a lot of energy, it is most cost-efficient to maintain the highest possible relative humidity while still maintaining a rigid flower stem. In order to find the optimal balance between stem rigidity and energy consumption, a monitoring technique is developed that can recognize early signs of the type of high-humidity exposure that eventually leads to toppling. The monitoring technique is based on spectral imaging and a linear classifier that predicts whether the tulips have been forced in an adequately ventilated environment or a poorly ventilated, high-RH enclosure. The model's classification accuracy was found to reach 100% 6-10 days before toppling occurs.

Influence of the mold growth on the crystallographic composition of hemp mortar

The use of hemp mortar as a bio-based insulation composite is widely promoted in the construction sector in France due to its environmental and hygrothermal advantages and the availability and low price of hemp fibers. Nevertheless, the use of such materials claims the consideration of the microbiological contamination that could lead to its degradation. Molds are known for their ability to modify locally the composition of hemp mortar by decreasing the pH level. That’s why the main objectives of the present work are, first, to expose the hemp mortar favorable conditions for mold growth, secondly, to investigate the proliferation of the mold filaments inside the hemp mortar sample and, then, to analyze the crystallographic composition. Experimentally, hemp mortar samples were exposed to high level of relative humidity during one year until the mold growth. The SEM observation allowed to follow the internal growth and identify the depth of the mold growth. Finally, the composition of the contaminated hemp mortar was studied by X-ray diffraction. The obtained results reveal that molds growth occurs not only on the surface but also in the depth. Nevertheless, as the mold growth started only after one year of high humidity exposure, a good resistance of studied hemp mortar towards molds was noted. Furthermore, the mineralogical composition analysis of the contaminated samples shows that the hydrates responsible for durability remained. These results provide data to better predict the durability of hemp mortars.

Predicting coronavirus disease (COVID-19) outcomes in the United States early in the epidemic

By 21 October 2020, the coronavirus disease (COVID-19) epidemic in the United States (US) had infected 8.3 million people, resulting in 61,364 laboratory-confirmed hospitalizations and 222,157 deaths. Currently, policymakers are trying to better understand this epidemic, especially the human-to-human transmissibility of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in relation to social, populational, air travel related and environmental exposure factors. Our study used 50 US states’ public health surveillance datasets (January 1-April 1, 2020) to measure associations of confirmed COVID-19 cases, hospitalizations and deaths with these variables. Using the resulting associations and multivariate regression (Negative Binomial and Poisson), predicted cases, hospitalizations and deaths were generated for each US state early in the epidemic. Factors associated with a significantly increased risk of COVID-19 disease, hospitalization and death included: population density, enplanement, Black race and increased sun exposure; in addition, COVID-19 disease and hospitalization were also associated with morning humidity. Although predictions of the number of cases, hospitalizations and deaths due to COVID-19 were not accurate for every state, those states with a combination of large number of enplanements, high population density, high proportion of Black residents, high humidity or low sun exposure may expect more rapid than expected growth in the number of COVID-19 events early in the epidemic.

Modification of the effects of nitrogen dioxide and sulfur dioxide on congenital limb defects by meteorological conditions.

Can meteorological conditions modify the associations between NO2 and SO2 exposure and congenital limb defects (CLDs) during the first trimester of pregnancy? Increases in NO2 and SO2 exposure were consistently associated with higher risks of CLDs during the first trimester of pregnancy; both low- and high-temperature exposure and high air humidity act synergistically with the two air pollutants on CLDs. Animal studies have indicated air pollutants are associated with CLDs, but corresponding epidemiological studies are limited with equivocal conclusions. Meteorological conditions are closely connected to the generation, diffusion, distribution and even chemical toxicity of air pollutants. This case-control study included 972 cases of CLDs and 9720 controls in Changsha, China during 2015-2018. Cases from the hospital based monitoring system for birth defects (including polydactyly, syndactyly, limb shortening, and clubfoot) and healthy controls from the electronic medical records system were studied. Complete data on daily average NO2 and SO2 concentrations and meteorological variables were obtained from local monitoring stations to estimate monthly individual exposures during the first trimester of pregnancy, using the nearest monitoring station approach for NO2 and SO2 concentrations, and the city-wide average approach for temperature and relative humidity, respectively. The 25th and 75th percentiles of daily mean temperature, as well as the 50th percentile of daily mean relative humidity during the study period were used to classify high- and low-temperature exposure, and high humidity exposure based on existing evidence and local climate characteristics. Multivariate logistic regression models were used to estimate the independent effects per 10 μg/m3 increase in NO2 and SO2 on CLDs, and the attribute proportions of interaction (API) were used to quantify the additive joint effects of air pollutants with meteorological conditions after including a cross product interaction term in the regression models. NO2 and SO2 exposures during the first trimester of pregnancy were consistently and positively associated with overall CLDs and subtypes, with adjusted odd ratios (aORs) ranging from 1.13 to 1.27 for NO2, and from 1.37 to 2.49 for SO2. The effect estimates were generally observed to be the strongest in the first month and then attenuated in the second and third months of pregnancy. Synergistic effects of both low and high temperature in combination with NO2 (with APIs ranging from 0.07 to 0.38) and SO2 (with APIs ranging from 0.18 to 0.51) appeared in the first trimester of pregnancy. Several significant modifying effects by high humidity were also observed, especially for SO2 (with APIs ranging from 0.13 to 0.38). Neither NO2 nor SO2 showed an interactive effect with season of conception. The methods used to estimate individual exposure levels of air pollutants and meteorological factors may lead to the misclassification bias because of the lack of information on maternal activity patterns and residential mobility during pregnancy. Moreover, we were unable to consider several potentially confounding factors, including socioeconomic status, maternal nutrient levels, alcohol use and smoking during early pregnancy due to unavailable data, although previous studies have suggested limited change to the results after when including these factors in the analysis. The findings are helpful for understanding the combined effects of air pollution and meteorological conditions on birth defects. Environmental policies and practices should be formulated and implemented to decrease air pollutant emissions and improve meteorological conditions to reduce their harmful effects on pregnancy. Additionally, pregnant women should be suggested to reduce outdoor time when the air quality is poor, especially when ambient temperature is higher or lower than what is comfortable, or when it is excessively humid. The study is funded by Major Scientific and Technological Projects for Collaborative Prevention and Control of Birth Defects in Hunan Province (2019SK1012), Major Research and Development Projects in Hunan Province (2018SK2060) and Scientific and Technological Department Projects in Hunan Province (2017SK50802). There are no competing interests. N/A.

'Occupational dermatoses from Personal Protective Equipment during the COVID-19 pandemic in the tropics - A Review'.

The COVID-19 pandemic has enveloped the world and there has been a high incidence of occupational dermatoses related to Personal Protective Equipment (PPE) amongst healthcare workers (HCWs) during this period. Prevention and management of these conditions will not only improve staff morale and quality of life, but will also minimize the risk of breaching PPE protocol due to such symptoms. The tropical climate in Singapore predisposes HCWs to more skin damage and pruritus due to intense heat, high humidity and sun exposure. The effects of friction, occlusion, hyperhidrosis and overheating on the skin in the tropics should not be neglected. Preventive measures can be taken based on our recommendations, and the working environment can be made more conducive for frontline HCWs. We review the literature and discuss various preventive and management strategies for these occupational skin diseases for our frontline HCWs, especially those working in less controlled working environments beyond the hospital in Singapore. Shorter shifts and frequent breaks from PPE are recommended. Duration of continuous PPE-usage should not exceed 6h, with breaks in non-contaminated areas every 2-3h to hydrate and mitigate the risk of skin reactions. Other strategies, such as teledermatology, should be considered so that consultations can remain accessible, while ensuring the safety and well-being of our clinical staff.

Reproductive activity, microhabitat use, and calling sites of Pristimantis bacchus (Anura: Craugastoridae)

Abstract Pristimantis bacchus is an endangered terrestrial frog, endemic to cloud forests of the northern part of the Cordillera Oriental in the Colombian Andes. The knowledge of its reproductive biology and microhabitat use can offer important information for future conservation programs. We evaluated the reproductive activity and microhabitat use for both sexes, and selection of calling sites by males during rainy and dry seasons. Individuals of all reproductive conditions were observed throughout the sampled months; however, we observed a higher abundance of frogs during the first rainy season, after the driest months of the year. Thus, this population seems to have continuous reproductive activity, with an apparent peak at the onset of the first rainy season of the year. There were differences in the microhabitat use between sexes, between adults and juveniles, and between non-reproductive and reproductive females. Males use a wider variety of substrates at higher perches, while females were mainly found on leaf litter and over leaves at low heights; however, ovigerous females mostly occupied substrates above 120 cm. Juveniles were less abundant than adults, and occupy low substrates, mostly at forest litter. Two selection models evaluated the preference for calling sites, related to physiological requirements of humidity and for vocal sound dispersion. Males preferred to vocalize on perches at heights among 41-120 cm and with a vegetal structure that maintains high humidity, avoiding desiccation, and reducing exposure to predators. Therefore, intrapopulation variation in microhabitat use in this species is related to age, sex, reproductive condition, and physiological requirements.

Determination and Data Correlation of Solubility of Sofosbuvir Polymorphs in Ethyl Acetate + Toluene and Methyl tert-Butyl Ether Binary Solvents at the Temperature Range from 268.15 to 308.15 K

A gravimetric method was used to experimentally determine the (solid + liquid) equilibrium of sofosbuvir of crystalline forms A and B in both ethyl acetate + toluene and methyl tert-butyl ether (MTBE) + toluene binary solvents systems at atmosphere pressure. Experiments were carried out at a temperature range of 268.15−308.15 K. Results show that the solubility of sofosbuvir increases with temperature, and the solubility of form B was higher than that of form A. The modified Apelblat model, the CNIBS/Redlich–Kister model, and the combined version of Jouyban–Acree model were employed to correlate the measured solubility data, respectively. Furthermore, an examination of the solid-state stability of the two polymorphs was conducted, finding that form A and form B exhibit good solid-state stability under high temperature, high humidity, and strong light exposure conditions.

Exposure to both formaldehyde and high relative humidity exacerbates allergic asthma by activating the TRPV4-p38 MAPK pathway in Balb/c mice

Some studies have indicated that formaldehyde, a ubiquitous environmental pollutant, can induce or aggravate allergic asthma. Epidemiological studies have also shown that the relative humidity indoors may be an independent and a key factor associated with the aggravation of allergic asthma. However, the synergy of humidity and formaldehyde on allergic asthma and the mechanism underlying this effect remain largely unknown. In this study, we aim to determine the effect of high relative humidity and/or formaldehyde exposure on allergic asthma and explore the underlying mechanisms. Male Balb/c mice were modeled with ovalbumin (OVA) and exposure to 0.5 mg/m3 formaldehyde and/or different relative humidity (60%/75%/90%). Histopathological changes, pulmonary function, Th1/Th2 balance, the status of mucus hypersecretion and the levels of inflammatory factors were detected to assess the exacerbation of allergic asthma. The levels of the transient receptor potential vanilloid 4 (TRPV4), calcium ion and the activation of p38 mitogen-activated protein kinases (p38 MAPK) were detected to explore the underlying mechanisms. The results showed that exposure to high relative humidity or to 0.5 mg/m3 formaldehyde alone had a slight, but not significant, affect on allergic asthma. However, the pathological response and airway hyperresponsiveness (AHR) were greatly aggravated by simultaneous exposure to 0.5 mg/m3 formaldehyde and 90% relative humidity. Blocking TRPV4or p38 MAPK using HC-067047 and SB203580 respectively, effectively alleviated the exacerbation of allergic asthma induced by this simultaneous exposure to formaldehyde and high relative humidity. The results show that when formaldehyde and high relative humidity are present this can enhance the activation of the TRPV4 ion channel in the lung leading to the aggravation of the p38 MAPK activation, resulting in the exacerbation of inflammation and hypersecretion of mucus in the airways.