Testosterone is closely related to Leydig cell activity, environmental factors, and androgen receptor distribution in adult male lizards of Liolaemus cuyanus (Reptilia: Liolaemidae) during the reproductive cycle

Testosterone, the primary sex hormone in male lizards, is closely linked to Leydig cell activity (the cells where steroidogenesis occurs) throughout the reproductive cycle, but testosterone action is related to androgen receptors (ARs) distribution in the seminiferous epithelium. In temperate zones, environmental factors detected through the hypothalamic-pituitary-gonadal axis, downregulate plasma testosterone, resulting in a seasonal reproductive cycle. The aim of this work is to study plasma testosterone in adult male lizards of Liolaemus cuyanus, an oviparous species, throughout its reproductive cycle and its relationship with Leydig cell histology, TotalLeydigCell/ActiveLeydigCell (TLC/ALC) ratio, environmental factors (temperature, relative humidity and solar irradiation) and ARs distribution in seminiferous epithelium. Specimens (N = 27) were captured (October to March) in a semi-arid zone (Valle de Matagusanos, San Juan, Argentina) and grouped into three relevant reproductive periods: pre-reproductive (PrR), reproductive (R), and post-reproductive (PsR). Significant differences in plasma testosterone were found among these periods, highest during R than in PsR. A significant positive correlation between plasma testosterone and TLC/ALC ratio was also observed. Plasma testosterone has a significant positive correlation only with solar irradiation, but not with the other variables. In PrR and R, ARs distribution was cytoplasmic and nuclear, shifting to only cytoplasmic in PsR. These results highlight the close correspondence between plasma testosterone, Leydig cell histology and activity, environmental factors, and ARs distribution, resulting in a synchronization that allows males of L. cuyanus to coordinate their reproductive cycle with the most favorable environmental conditions, probably for mating and birth of offspring.

Effects of ambient temperature, relative humidity and absolute humidity on risk of nasopharyngeal carcinoma in China

Nasopharyngeal carcinoma (NPC) has a unique geographic distribution. It is unknown whether meteorological factors are related to the incidence of NPC. To investigate the effect of ambient temperature, relative humidity (RH), and absolute humidity (AH) on the incidence of NPC, we collected the incidence rate of NPC in 2016 and meteorological data from 2006 to 2016 from 484 cities and counties across 31 provinces in China. Generalized additive models with quasi-Poisson regression and generalized linear models with natural cubic splines were employed respectively to elucidate the nonlinear relationships and specify the partial linear relationships. Subgroup and interactive analysis were also conducted. Temperature (R2 = 0.68, p < .001), RH (R2 = 0.47, p < .001), and AH (R2 = 0.70, p < .001) exhibited nonlinear correlations with NPC incidence rate. The risk of NPC incidence increased by 20.3% (95% confidence intervals [CI]: [18.9%, 21.7%]) per 1°C increase in temperature, by 6.3% (95% CI: [5.3%, 7.2%]) per 1% increase in RH, and by 32.2% (95% CI: [30.7%, 33.7%]) per 1 g/m3 increase in AH, between their the 25th and the 99th percentiles. In addition, the combination of low temperature and low RH was also related to increased risk (relative risk: 1.60, 95% CI: [1.18, 2.17]). Males and eastern or rural populations tended to be more vulnerable. In summary, this study suggests that ambient temperature, RH, and particularly AH are associated with the risk of NPC incidence.

Dependence on relative humidity in the formation of reactive oxygen species in water droplets

Water microdroplets (7 to 11 µm average diameter, depending on flow rate) are sprayed in a closed chamber at ambient temperature, whose relative humidity (RH) is controlled. The resulting concentration of ROS (reactive oxygen species) formed in the microdroplets, measured by the amount of hydrogen peroxide (H2O2), is determined by nuclear magnetic resonance (NMR) and by spectrofluorimetric assays after the droplets are collected. The results are found to agree closely with one another. In addition, hydrated hydroxyl radical cations (•OH-H3O+) are recorded from the droplets using mass spectrometry and superoxide radical anions (•O2-) and hydroxyl radicals (•OH) by electron paramagnetic resonance spectroscopy. As the RH varies from 15 to 95%, the concentration of H2O2 shows a marked rise by a factor of about 3.5 in going from 15 to 50%, then levels off. By replacing the H2O of the sprayed water with deuterium oxide (D2O) but keeping the gas surrounding droplets with H2O, mass spectrometric analysis of the hydrated hydroxyl radical cations demonstrates that the water in the air plays a dominant role in producing H2O2 and other ROS, which accounts for the variation with RH. As RH increases, the droplet evaporation rate decreases. These two facts help us understand why viruses in droplets both survive better at low RH values, as found in indoor air in the wintertime, and are disinfected more effectively at higher RH values, as found in indoor air in the summertime, thus explaining the recognized seasonality of airborne viral infections.

π-Extended Porphyrin-Phthalocyanine Heterojunction Devices Exhibiting High Ammonia Sensitivity with a Remarkable Light Effect

π-Extended porphyrins represent an attractive class of organic compounds because of their unique photophysical, optoelectronic, and physicochemical properties. Herein, cross-conjugated (Ace-PQ-Ni) and linear-conjugated (AM6) porphyrins are used to build double-layer heterojunction devices by combining them with a lutetium bisphthalocyanine complex (LuPc2). The heterojunction effect at the porphyrin-phthalocyanine interface plays a key role in the charge transport properties. Both devices exhibit exceptionally high ammonia sensitivity at room temperature and under ambient relative humidity, with limit of detection values of 156 and 115 ppb for Ace-PQ-Ni/LuPc2 and AM6/LuPc2 sensors, respectively. Interestingly, the Ace-PQ-Ni/LuPc2 and AM6/LuPc2 sensors display opposite effects upon light illumination. While the former sensors show largely decreased ammonia sensitivity under light illumination, the current variation of the latter under ammonia is remarkably enhanced with a multiplication factor of 13 and a limit of detection (LOD) of 83 ppb. The striking difference in their sensing properties upon light illumination is attributed to their different π-conjugation pathways (cross-conjugation versus linear conjugation).

Simultaneous Water Sorption and Crystallization in ASDs 1: Stability Studies Lasting for Two Years

One way to increase the slow dissolution rate and the associated low bioavailability of newly developed active pharmaceutical ingredients (APIs) is to dissolve the API in a polymer, leading to a so-called amorphous solid dispersion (ASD). However, APIs are often supersaturated in ASDs and thus tend to crystallize during storage. The kinetics of the crystallization process is determined by the amount of water the ASD absorbs during storage at relative humidity (RH), storage temperature, polymer type, and the drug load of the ASD. Here, the crystallization kinetics and shelf life of spray-dried ASDs were investigated for ASDs consisting of nifedipine (NIF) or celecoxib (CCX) as the APIs and of poly(vinylpyrrolidone-co-vinyl acetate) or hydroxypropyl methylcellulose acetate succinate as polymers. Samples were stored over 2 years at different RHs covering conditions above and below the glass transition of the wet ASDs. Crystallization kinetics and onset time of the crystallization were qualitatively studied by using powder X-ray diffraction and microscopic inspection and were quantitatively determined by using differential scanning calorimetry. It was found that the NIF ASDs crystallize much faster than CCX ASDs at the same drug load and at the same storage conditions due to both higher supersaturation and higher molecular mobility in the NIF ASDs. Experimental data on crystallization kinetics were correlated using the Johnson-Mehl-Avrami-Kolmogorov equation. A detailed thermodynamic and kinetic modeling will be performed in Part 2 of this paper series.

Flower production decreases with warmer and more humid atmospheric conditions in a western Amazonian forest

Climate models predict that everwet western Amazonian forests will face warmer and wetter atmospheric conditions, and increased cloud cover. It remains unclear how these changes will impact plant reproductive performance, such as flowering, which plays a central role in sustaining food webs and forest regeneration. Warmer and wetter nights may cause reduced flower production, via increased dark respiration rates or alteration in the reliability of flowering cue-based processes. Additionally, more persistent cloud cover should reduce the amounts of solar irradiance, which could limit flower production. We tested whether interannual variation in flower production has changed in response to fluctuations in irradiance, rainfall, temperature, and relative humidity over 18 yrs in an everwet forest in Ecuador. Analyses of 184 plant species showed that flower production declined as nighttime temperature and relative humidity increased, suggesting that warmer nights and greater atmospheric water saturation negatively impacted reproduction. Species varied in their flowering responses to climatic variables but this variation was not explained by life form or phylogeny. Our results shed light on how plant communities will respond to climatic changes in this everwet region, in which the impacts of these changes have been poorly studied compared with more seasonal Neotropical areas.

Relationship between Desiccation Tolerance and Biofilm Formation in Shiga Toxin-Producing Escherichia coli

Shiga toxin-producing Escherichia coli (STEC) is a major concern in the food industry and requires effective control measures to prevent foodborne illnesses. Previous studies have demonstrated increased difficulty in the control of biofilm-forming STEC. Desiccation, achieved through osmotic stress and water removal, has emerged as a potential antimicrobial hurdle. This study focused on 254 genetically diverse E. coli strains collected from cattle, carcass hides, hide-off carcasses, and processing equipment. Of these, 141 (55.51%) were STEC and 113 (44.48%) were generic E. coli. The biofilm-forming capabilities of these isolates were assessed, and their desiccation tolerance was investigated to understand the relationships between growth temperature, relative humidity (RH), and bacterial survival. Only 28% of the STEC isolates had the ability to form biofilms, compared to 60% of the generic E. coli. Stainless steel surfaces were exposed to different combinations of temperature (0 °C or 35 °C) and relative humidity (75% or 100%), and the bacterial attachment and survival rates were measured over 72 h and compared to controls. The results revealed that all the strains exposed to 75% relative humidity (RH) at any temperature had reduced growth (p < 0.001). In contrast, 35 °C and 100% RH supported bacterial proliferation, except for isolates forming the strongest biofilms. The ability of E. coli to form a biofilm did not impact growth reduction at 75% RH. Therefore, desiccation treatment at 75% RH at temperatures of 0 °C or 35 °C holds promise as a novel antimicrobial hurdle for the removal of biofilm-forming E. coli from challenging-to-clean surfaces and equipment within food processing facilities.

Influence of Service Conditions and Mix Design on the Physical-Mechanical Properties of Roller-Compacted Concrete for Pavement

This research focuses on the behavior of roller-compacted concrete (RCC) used in pavements, which are prone to deterioration affecting their performance. These deteriorations result from various causes, including traffic load, errors during construction, mix design, and ambient conditions. Among these, ambient conditions could lead to a marked variable impact on material behavior and durability depending on the conditions associated with each region. Accordingly, this study aims to deepen the understanding of the effect, which a broader range of ambient conditions and different mix designs have on the physical and mechanical properties of RCC. Measurements such as the amount of water vapor per kilogram of air were used to apply the findings comprehensively. The RCC analysis encompassed experimentation with different compositions, altering the cement water ratio amount, and adding a superplasticizer. The impact of curing on the materials was evaluated before subjecting them to various humidity and temperature conditions. Laboratory tests were conducted to measure performance, including moisture, shrinkage, compressive strength, and the progression of flexural fracture resistance over curing periods of up to 90 days. The results revealed a logarithmic correlation between shrinkage and ambient humidity, which is the most determining factor in performance. Mix optimization through increased cement and reduced water enhanced the tensile strength of the material. Furthermore, the curing process was confirmed to increase resistance to shrinkage, especially in the long term, establishing it as a crucial element for the structural stability of RCC, which is relatively insensitive to variations in ambient conditions.

Thermal Impact and the Relevance of Body Size and Activity on the Oxygen Consumption of a Terrestrial Snail, Theba pisana (Helicidae) at High Ambient Temperatures

Metabolism, mainly driven by oxygen consumption, plays a key role in life, as it is one of the main ways to respond to extreme temperatures through internal processes. Theba pisana, a widespread Mediterranean land snail, is exposed to a wide range of ambient temperature. In this species the oxygen consumption was tested as a response variable by multiple regression modelling on the "explanatory" variables shell-free mass, temperature, and relative humidity. Our results show that the oxygen consumption of T. pisana can be well described (73.1%) by these three parameters. In the temperature range from 23 °C to 35 °C the oxygen consumption decreased with increasing temperature. Relative humidity, in the range of 67% to 100%, had the opposite effect: if it increases, oxygen consumption will increase as well. Metabolism is proportional to an individual's mass to the power of the allometric scaling exponent α, which is between 0.62 and 0.77 in the mentioned temperature range. CT scans of shells and gravimetry revealed the shell-free mass to be calculated by multiplying the shell diameter to the third power by 0.2105. Data were compared to metabolic scaling exponents for other snails reported in the literature.

Dynamics and Viability of Airborne Respiratory Syncytial Virus under Various Indoor Air Conditions

The factors governing the viability of airborne viruses embedded within respiratory particles are not well understood. This study aimed to investigate the relative humidity (RH)-dependent viability of airborne respiratory syncytial virus (RSV) in simulated respiratory particles suspended in various indoor air conditions. We tested airborne RSV viability in three static indoor air conditions, including sub-hysteresis (RH < 39%), hysteresis (39% < RH < 65%), and super-hysteresis (RH > 65%) air as well as in three dynamic indoor air conditions, including the transitions between the static conditions. The dynamic conditions were hysteresis → super-hysteresis → hysteresis, sub-hysteresis → hysteresis, and super-hysteresis → hysteresis. We found that after 45 min of particle aging in static conditions, the viability of RSV in sub-hysteresis, hysteresis, and super-hysteresis air was 0.72% ± 0.06%, 0.03% ± 0.006%, and 0.27% ± 0.008%, respectively. After 45 min of aging in dynamic conditions, the RSV viability decreased for particles that remained in a liquid (deliquesced) state during aging when compared with particles in a solid (effloresced) state. The decreased viability of airborne RSV for deliquesced particles is consistent with prolonged exposure to elevated aqueous solutes. These results represent the first measurements of the survival of airborne RSV over particle aging time, with equal viability in low, intermediate, and high RHs at 5 and 15 min and a V-shaped curve after 45 min.

Dehydration stress and Mayaro virus vector competence in Aedes aegypti

IMPORTANCE

Relative humidity (RH) is an environmental variable that affects mosquito physiology and can impact pathogen transmission. Low RH can induce dehydration in mosquitoes, leading to alterations in physiological and behavioral responses such as blood-feeding and host-seeking behavior. We evaluated the effects of a temporal drop in RH (RH shock) on mortality and Mayaro virus vector competence in Ae. aegypti. While dehydration induced by humidity shock did not impact virus infection, we detected a significant effect of dehydration on mosquito mortality and blood-feeding frequency, which could significantly impact transmission dynamics.

Alkali-Silica Reactions: Literature Review on the Influence of Moisture and Temperature and the Knowledge Gap

The alkali-silica reaction is a universally known destructive mechanism in concrete that can lead to the premature loss of serviceability in affected structures. Quite an enormous number of research studies have been carried out focusing on the mechanisms involved as well as the mitigation and prevention of the reaction. A few in-depth discussions on the role of moisture and temperature exist in the literature. Nevertheless, moisture and temperature have been confirmed to play a vital role in the reaction. However, critical assessments of their influence on ASR-induced damage are limited. The available moisture in concrete needed to initiate and sustain the reaction has been predominantly quantified with the relative humidity as a result of difficulties in the use of other media, like the degree of capillary saturation, which is more scientific. This paper discussed the current state of understanding of moisture measurement in concrete, the role of moisture and temperature in the kinetics of the reaction, as well as the moisture threshold needed for the reaction. Furthermore, the influence of these exposure conditions on the internal damage caused by ASR-induced deterioration was discussed.

Preventive Conservation of a Short Theatre Skit (Valencian "Sainete") with Cloud Data Storage and Internet of Things

Preventing the progressive deterioration of works of art over time is a topic of great interest to collectors and museums. With this aim, time capsules where environmental conditions remain unchanged are well known for preserving art. In this paper, a prototype of an IoT time capsule is presented with a focus on low cost in order to make it accessible to private collectors or small museums with tight budgets. Valencian 'sainetes' (small plays), which are considered materials of artistic interest, have been placed in a "time capsule", which is a manually made container with insulating materials for keeping small pieces for a long time. Environmental control has been performed with a low-cost microcontroller, sensors and actuators connected to a free online IoT platform. This platform recorded data and made decisions based on these data, sending cooling or heating orders to an environmental control system. The results obtained are very satisfactory and open interesting perspectives for future research. However, they also highlight some relevant technical and economic limitations that will have to be considered in the future.

The short-term effect of weather variables on heart rate variability in patients after open-heart surgery

The aim of the study was to detect the associations between heart rate variability (HRV) and weather variables in patients who underwent coronary artery bypass grafting or valve surgery. The study was performed in Kaunas, Lithuania, during 2008-2012. We used data of 220 patients. HRV was assessed by a 5-minute electrocardiogram. The data were collected at 1.5 months, 1 year, and 2 years after the surgery (495 measurements). A negative association of standard deviation of beat-to-beat interval (SDNN), very low frequency (VLF), low frequency, and high frequency (HF) powers with a decrease in air temperature (T) during a 3-day period in the range of T < 1°C wind speed >2.75 knots 2 days before, and the daily North Atlantic Oscillation indices were observed. The effect of wind speed on SDNN and VLF power was stronger in males. Two days after relative humidity >89%, a lower mean VLF and higher HF in normalized units were found; in females, this effect was stronger 1.5 months after the surgery. Among patients after open-heart surgery, the HRV variables may be related to specific weather changes and the effect of weather was different for males and females and at different times after the surgery.

Wearable Fiber SPR Respiration Sensor Based on a LiBr-Doped Silk Fibroin Film

Respiration is essential for supporting human body functions. However, a biocompatible fiber respiration sensor has rarely been discussed. In this study, we propose a wearable fiber surface plasmon resonance (SPR) respiration sensor using a LiBr-doped silk fibroin (SF) film. The SPR sensor monitors respiration by responding to airway humidity variation during inhalation and exhalation. We fabricated the SPR respiration sensor by depositing the core of a plastic-clad optical fiber with a gold film and an SF-LiBr composite film. The SF-LiBr composite film can absorb water through the interaction between water molecules and hydrogen bonds linking fibroin chains. Thus, humidity variation can change the SF-LiBr composite film's refractive index (RI), altering the phase-matching condition of the surface plasmon polaritons and shifting the SPR spectral dip. In experiments, we test the effect of the LiBr doping ratio on humidity response and confirm that the SF-22.1 wt % LiBr sensor has balanced performances. The SF-22.1 wt % LiBr sensor has a broad sensing range of 35-99% relative humidity (RH), a reasonable overall sensitivity of -6.5 nm/% RH, a fast response time of 135 ms, a quick recovery time of 150 ms, good reversibility, and good repeatability, which is capable of tracking different respiration states and patterns. Finally, we encapsulate this sensor in a conventional nasal oxygen cannula for wearable respiration monitoring, proving that the sensor is suitable for high-sensitivity, real-time, and accurate respiration monitoring.

Virus Dynamics and Decay in Evaporating Human Saliva Droplets on Fomites

The transmission of most respiratory pathogens, including SARS-CoV-2, occurs via virus-containing respiratory droplets, and thus, factors that affect virus viability in droplet residues on surfaces are of critical medical and public health importance. Relative humidity (RH) is known to play a role in virus survival, with a U-shaped relationship between RH and virus viability. The mechanisms affecting virus viability in droplet residues, however, are unclear. This study examines the structure and evaporation dynamics of virus-containing saliva droplets on fomites and their impact on virus viability using four model viruses: vesicular stomatitis virus, herpes simplex virus 1, Newcastle disease virus, and coronavirus HCoV-OC43. The results support the hypothesis that the direct contact of antiviral proteins and virions within the "coffee ring" region of the droplet residue gives rise to the observed U-shaped relationship between virus viability and RH. Viruses survive much better at low and high RH, and their viability is substantially reduced at intermediate RH. A phenomenological theory explaining this phenomenon and a quantitative model analyzing and correlating the experimentally measured virus survivability are developed on the basis of the observations. The mechanisms by which RH affects virus viability are explored. At intermediate RH, antiviral proteins have optimal influence on virions because of their largest contact time and overlap area, which leads to the lowest level of virus activity.

Simulating atmospheric drought: Silica gel packets dehumidify mesocosm microclimates

1. As global temperatures rise, droughts are becoming more frequent and severe. To predict how drought might affect plant communities, ecologists have traditionally designed experiments with controlled watering regimes and rainout shelters. Both treatments have proven effective for simulating soil drought. However, neither are designed to directly modify atmospheric drought. 2. Here, we detail the efficacy of a silica gel atmospheric drought treatment in outdoor mesocosms with and without a cooccurring soil drought treatment. At California State University, Los Angeles, we monitored relative humidity (RH), temperature, and vapor pressure deficit (VPD) every 10 minutes for five months in a bare-ground experiment featuring mesocosms treated with soil drought (reduced watering) and/or atmospheric drought (silica packets suspended 12 cm above soil). 3. We found that silica packets dehumidified these microclimates most effectively (-5% RH) when combined with reduced soil water, regardless of the ambient humidity levels of the surrounding air. Further, packets increased microclimate VPD most effectively (+0.4 kPa) when combined with reduced soil water and ambient air temperatures above 20°C. Finally, packets simulated atmospheric drought most consistently when replaced within three days of deployment. 4. Our results demonstrate the use of silica packets as effective dehumidification agents in outdoor drought experiments. We emphasize that incorporating atmospheric drought in existing soil drought experiments can improve our understandings of the ecological impacts of drought.

Polymer Microtip-Based Fabry-Perot Interferometer for Water Content Determination in the Gas and Liquid Phase

In this work, we present a Fabry-Perot interferometer (FPI) based on a polymer microtip for water content determination in both the gas and liquid phase. The polymer tip of pentaerythritol triacrylate (PETA) is fabricated at the end of an optical fiber by self-guiding photopolymerization, forming at the same time a low-fineness Fabry-Perot interferometer and a sensing layer for water thanks to hydroxyl groups present in PETA. The PETA tip shows a clear interferometric signal, which is highly sensitive to the change of the water content in the environment. The FPI signal shifts with a constant sensitivity of 90 pm/%RH, which corresponds to a relative sensitivity of 104 ppm/% RH, in the range of relative humidity from 30 to 80%. In liquid, the FPI sensor shows a nonlinear sensitivity, up to 158 pm/wt % as the water content is below 40 wt % in water/glycerol mixtures. The cross effect of the temperature on the PETA tip is demonstrated to be negligible as the FPI signal is insensitive to temperature changes from 23 to 70 °C. More importantly, the interaction between the tip and the environment affecting the FPI signal is demonstrated experimentally. The proposed FPI sensor is therefore promising for the direct, sensitive, and reliable determination of the water content of products.

Controllability of the Conductive Filament in Porous SiOx Memristors by Humidity-Mediated Silver Ion Migration

Oxide-based memristors composed of Ag/porous SiOx/Si stacks are fabricated using different etching time durations between 0 and 90 s, and the memristive properties are analyzed in the relative humidity (RH) range of 30-60%. The combination of humidity and porous structure provides binding sites to control silver filament formation with a confined nanoscale channel. The memristive properties of devices show high on/off ratios up to 108 and a dispersion coefficient of 0.1% of the high resistance state (CHRS) when the RH increases to 60%. Humidity-mediated silver ion migration in the porous SiOx memristors is investigated, and the mechanism leading to the synergistic effects between the porous structure and environmental humidity is elucidated. The artificial neural network constructed theoretically shows that the recognition rate increases from 60.9 to 85.29% in the RH range of 30-60%. The results and theoretical understanding provide insights into the design and optimization of oxide-based memristors in neuromorphic computing applications.

Distribution of Phlebotomus argentipes Annandale & Brunetti, 1908 in the Anuradhapura district, North Central Sri Lanka

Background & objectives

Phlebotomus argentipes Annandale & Brunetti, 1908 (Diptera: Psychodidae) is the main vector responsible for the transmission of Leishmania donovani (Laveran & Mesnil, 1903) Ross, 1903 in the subcontinent of India. It is the potential vector of cutaneous leishmaniasis in Sri Lanka. The present study determined ecological factors that influence the abundance of P. argentipes in areas with high disease prevalence in the Anuradhapura district, North Central Sri Lanka.

Methods

CDC light traps and yellow sticky traps were used for sampling, and abundance was recorded throughout 12 months with selected environmental parameters namely, relative humidity, wind speed, and temperature. The relationships between the abundance of P. argentipes with mean temperature, % relative humidity, and wind speed were tested with regression analysis. The temporal distribution of the vector population was tested with a time series analysis.

Results

The study identified the most preferable microhabitats of P. argentipes: shrubs, unclear areas, gardening areas, wet soil areas with leaf litter, and termite hills. The results indicated that the abundance of P. argentipes was highly dependent on mean temperature (P = 0.00, R2 = 68%), and a high number of P. argentipes was recorded for a low mean temperature range of 24.7-27.3°C. Furthermore, the abundance of P. argentipes exhibited an increasing trend with high humidity levels of 72-88% (P = 0.00, R2 = 91.6%).

Interpretation & conclusion

These findings may help predict the temporal variation of the potential vector population with studied ecological parameters and contribute to a successful vector management strategy with thorough knowledge of the behavioral pattern of P. argentipes.

The Influence of Short-Term Weather Parameters and Air Pollution on Adolescent Airway Inflammation

Fraction of exhaled Nitric Oxide (FeNO) is a marker of airway inflammation. We examined the main effects and interactions of relative humidity (RH) and air pollution on adolescents' FeNO. Two thousand and forty-two participants from the 15-year follow-up of the German GINIplus and LISA birth cohorts were included. Daily meteorological (maximum [Tmax], minimum [Tmin] and mean [Tmean] temperatures and RH) and air pollution [Ozone (O3), nitrogen dioxide (NO2) and particulate matter < 2.5 µm (PM2.5)] were assessed. Linear models were fitted with Ln(FeNO) as the outcome. Increases in FeNO indicate an increase in lung inflammation. Increased FeNO was associated with an increase in temperature, PM2.5, O3 and NO2. A 5% increase in RH was associated with a decrease in FeNO. Interactions between RH and high (p = 0.007) and medium (p = 0.050) NO2 were associated with increases in FeNO; while interactions between RH and high (p = 0.042) and medium (p = 0.040) O3 were associated with decreases in FeNO. Adverse effects were present for male participants, participants with low SES, participants with chronic respiratory disease, and participants from Wesel. Short-term weather and air pollution have an effect on lung inflammation in German adolescents. Future research should focus on further assessing the short-term effect of multiple exposures on lung inflammation in adolescents.

Best Practices for Body Temperature Measurement with Infrared Thermography: External Factors Affecting Accuracy

Infrared thermographs (IRTs) are commonly used during disease pandemics to screen individuals with elevated body temperature (EBT). To address the limited research on external factors affecting IRT accuracy, we conducted benchtop measurements and computer simulations with two IRTs, with or without an external temperature reference source (ETRS) for temperature compensation. The combination of an IRT and an ETRS forms a screening thermograph (ST). We investigated the effects of viewing angle (θ, 0-75°), ETRS set temperature (TETRS, 30-40 °C), ambient temperature (Tatm, 18-32 °C), relative humidity (RH, 15-80%), and working distance (d, 0.4-2.8 m). We discovered that STs exhibited higher accuracy compared to IRTs alone. Across the tested ranges of Tatm and RH, both IRTs exhibited absolute measurement errors of less than 0.97 °C, while both STs maintained absolute measurement errors of less than 0.12 °C. The optimal TETRS for EBT detection was 36-37 °C. When θ was below 30°, the two STs underestimated calibration source (CS) temperature (TCS) of less than 0.05 °C. The computer simulations showed absolute temperature differences of up to 0.28 °C and 0.04 °C between estimated and theoretical temperatures for IRTs and STs, respectively, considering d of 0.2-3.0 m, Tatm of 15-35 °C, and RH of 5-95%. The results highlight the importance of precise calibration and environmental control for reliable temperature readings and suggest proper ranges for these factors, aiming to enhance current standard documents and best practice guidelines. These insights enhance our understanding of IRT performance and their sensitivity to various factors, thereby facilitating the development of best practices for accurate EBT measurement.

Using environmental factors to predict Rhipicephalus sanguineus s.l. (Acari: Ixodidae) mortality

BACKGROUND

Rhipicephalus sanguineus s.l. (Latreille, 1806) can establish indoor populations, which increases the risk of pathogen transmission to humans and companion dogs. Rhipicephalus sanguineus s.l. ticks spend most of their life cycle off the host, which subjects developmental timescale to abiotic factors. Previous studies showed that both temperature and relative humidity (RH) influenced Rhipicephalus sanguineus s.l. survival time across all life stages. However, quantified relationships between environmental factors and Rhipicephalus sanguineus s.l. mortality is not currently available. Here, three Rhipicephalus sanguineus s.l. strains were evaluated for mortality under 20 combinations of five temperatures and four RHs. The data obtained were analyzed to quantify the relationship between environmental factors and Rhipicephalus sanguineus s.l.

SURVIVAL

RESULTS

Mortality probabilities did not show a consistent pattern between the three tick strains. Temperature, RH, and their interaction influenced Rhipicephalus sanguineus s.l. mortality probabilities across all life stages, with mortality probability generally increasing with temperature but decreasing with RH. With 50% and lower RH, larvae cannot survive for more than 1 week. However, mortality probabilities in all strains and stages were more sensitive to temperature than to RH.

CONCLUSION

This study identified the predictive relationship between environmental factors and Rhipicephalus sanguineus s.l. survival, which enables estimations of tick survival time under varied residential situations, allows parameterization of population models, and provides guidance for pest control professionals to develop efficient management strategies. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The Effect of Choline Salt Addition to Trehalose Solution for Long-Term Storage of Dried and Viable Nuclei from Fully Grown Oocytes

Although drying techniques are exciting alternatives to cryopreservation, it remains challenging to maintain tightly controlled temperatures and humidity levels during storage of dried products. The objective of this study was to determine if the addition of choline acetate to trehalose solution could enable a wider range of storage conditions for preservation of nuclei from fully grown oocytes, by allowing temporary humidity excursions (>44% relative humidity) that may lead to crystallization of trehalose and loss of DNA integrity. Using domestic cat germinal vesicle oocytes as a model, we characterized the recovery as well as the integrity of samples after microwave-assisted dehydration. Exposure to choline acetate alone did not impair the germinal vesicle's DNA integrity and only had a negative impact on the chromatin configuration. Choline acetate addition enabled us to reach lower moisture contents after 25 min of microwave-assisted drying. Sample recovery after rehydration was also better in the presence of choline acetate. The integrity of the germinal vesicle's DNA was not affected, while the chromatin configuration was impaired by the presence of choline acetate during dehydration. Importantly, choline acetate addition helped to maintain an amorphous state (absence of detrimental crystallization) during excursion from ideal humidity conditions.

Skin Friction: Mechanical and Tribological Characterization of Different Papers Used in Everyday Life

The coefficient of friction for different contacting materials against skin is mainly influenced by the nature of the materials (synthetic and natural fabrics), mechanical contact parameters (interfacial pressure and sliding velocities), and physiological skin conditions (ambient humidity and skin moisture content). In the present research work, seven different types of papers used in everyday life were analyzed. The physical properties of these materials were determined through tensile tests and friction tests. By comparing mechanical properties with coefficient of friction, it was possible to conclude that the coefficient of friction is strongly correlated with the mechanical properties.

Broad Scale Spatial Modelling of Wet Bulb Globe Temperature to Investigate Impact of Shade and Airflow on Heat Injury Risk and Labour Capacity in Warm to Hot Climates

While shade and air flow are recognised factors that reduce outdoor heat exposure, the level of reduction in terms of labour capacity at varying air temperature and humidity levels is poorly understood. This study investigated cooling effects on the commonly used heat index, wet bulb globe temperature (WBGT), and subsequent impact on labour capacity, for a range of air flow and shade conditions in warm to hot climates. We modelled heat exposure using a physics-based method to map WBGT for a case study region which experiences a range of heat categories with varying levels of health risks for outdoor workers. Continent-scale modelling confirmed significant spatial variability in the effect of various shade and wind speed scenarios across a range of real-world mid-summer daytime conditions. At high WBGTs, increasing shade or air flow for outdoor workers lowered heat exposure and increases labour capacity, with shade giving the greatest benefit, but cooling varied considerably depending upon underlying air temperature and humidity. Shade had the greater cooling effect; reducing incident radiation by 90% decreased WBGT by 2-6 °C depending on location. Wind had a lower cooling effect in the hottest regions, with a decreasing exponential relationship between wind speed and WBGT observed.

Effect of relative humidity on the desorption of odour-active volatile organic compounds from paper and board: sensory evaluation and migration to Tenax®

Paper and board are used for packaging of moist as well as dry food. According to Regulation (EC) No. 1935/2004, food contact materials (FCM) must not bring about a deterioration in the organoleptic characteristics of foodstuffs. For testing the transfer of off-flavour (taint) from packaging to food via the gas phase (DIN EN 1230-2), relative humidity (rH) has to be adjusted. In contrast, rH is neither taken into account when testing the odour (DIN EN 1230-1), nor in chemical migration of volatile organic substances (VOC) onto the adsorbent Tenax® (DIN EN 14338). In this work, effect of different rHs on the desorption of VOC from paper and board was investigated by GC-MS analysis as well as by human sensory tests. Raising humidity led to an increase in VOC transfer, which was observed by increasing peak areas as well as the detection of more substances in GC-MS. Analytical results were in line with human sensory tests. The odour profile of the paper at 33 and 58% rH was described as cardboard-like, sweet and smoky. Impact substances for these olfactory impressions were (E)-2-nonenal, vanillin and 2-methoxyphenol as identified by GC with an olfactory detection port (GC-ODP). The increase to 75 and 100% rH resulted in the additional perception of cheesy/sweaty and fatty/rancid impressions, which were primarily caused by short-chain fatty acids and di-unsaturated aldehydes.

Moisture Adsorption-Desorption Behaviour in Nanocomposite Copolymer Films

Dehumidifying air via refrigerant cooling method consumes a tremendous amount of energy. Independent humidity control systems using desiccants have been introduced to improve energy efficiency. This research aimed to find an alternative to the commonly used solid desiccant, silica gel, which has weak physical adsorption properties. It also aimed to overcome the limitation of liquid desiccants that may affect indoor air quality and cause corrosion. This study reports on the synthesis of poly(vinyl alcohol-co-acrylic acid), P(VA-AA), through solution polymerisation by hydrolysing poly(vinyl acetate-co-acrylic acid), P(VAc-AA). This viable copolymer was then incorporated with graphene oxide (GO) at different concentrations (0 wt.%, 0.5 wt.%, 2 wt.% and 5 wt.%) to enhance the adsorption-desorption process. The samples were tested for their ability to adsorb moisture at different levels of relative humidity (RH) and their capability to maintain optimum sorption capacity over 10 repeated cycles. The nanocomposite film with 2% GO, P(VA-AA)/GO2, exhibited the highest moisture sorption capacity of 0.2449 g/g for 60-90% RH at 298.15 K, compared to its pristine copolymer, which could only adsorb 0.0150 g/g moisture. The nanocomposite desiccant demonstrated stable cycling stability and superior desorption in the temperature range of 318.15-338.15 K, with up to 88% moisture desorption.

Variability in Donor Lung Culture and Relative Humidity Impact the Stability of 2009 Pandemic H1N1 Influenza Virus on Nonporous Surfaces

Respiratory viruses can be transmitted by multiple modes, including contaminated surfaces, commonly referred to as fomites. Efficient fomite transmission requires that a virus remain infectious on a given surface material over a wide range of environmental conditions, including different relative humidities. Prior work examining the stability of influenza viruses on surfaces has relied upon virus grown in media or eggs, which does not mimic the composition of virus-containing droplets expelled from the human respiratory tract. In this study, we examined the stability of the 2009 pandemic H1N1 (H1N1pdm09) virus on a variety of nonporous surface materials at four different humidities. Importantly, we used virus grown in primary human bronchial epithelial cell (HBE) cultures from different donors to recapitulate the physiological microenvironment of expelled viruses. We observed rapid inactivation of H1N1pdm09 on copper under all experimental conditions. In contrast to copper, viruses were stable on polystyrene plastic, stainless steel, aluminum, and glass, at multiple relative humidities, but greater decay on acrylonitrile butadiene styrene (ABS) plastic was observed at short time points. However, the half-lives of viruses at 23% relative humidity were similar among noncopper surfaces and ranged from 4.5 to 5.9 h. Assessment of H1N1pdm09 longevity on nonporous surfaces revealed that virus persistence was governed more by differences among HBE culture donors than by surface material. Our findings highlight the potential role of an individual's respiratory fluid on viral persistence and could help explain heterogeneity in transmission dynamics. IMPORTANCE Seasonal epidemics and sporadic pandemics of influenza cause a large public health burden. Although influenza viruses disseminate through the environment in respiratory secretions expelled from infected individuals, they can also be transmitted by contaminated surfaces where virus-laden expulsions can be deposited. Understanding virus stability on surfaces within the indoor environment is critical to assessing influenza transmission risk. We found that influenza virus stability is affected by the host respiratory secretion in which the virus is expelled, the surface material on which the droplet lands, and the ambient relative humidity of the environment. Influenza viruses can remain infectious on many common surfaces for prolonged periods, with half-lives of 4.5 to 5.9 h. These data imply that influenza viruses are persistent in indoor environments in biologically relevant matrices. Decontamination and engineering controls should be used to mitigate influenza virus transmission.

Impact of climatic factors on temporal variability of sand fly abundance in Sri Lanka: Longitudinal study (2018 to 2020) with two-stage hierarchical analysis

Background

Phlebotomine sand flies serve as vectors for leishmaniasis, a major health concern, but a neglected tropical disease. The risk of vector activity is governed by climatic factors that vary in different geographic zones in the country. Thus, we aimed to quantify the effect of climatic variables on sand fly vector activity in ten sentinel sites across Sri Lanka.

Methods

Mean rainfall, ambient temperature, relative humidity, wind speed, soil temperature, evaporation, sunshine hours, and vector densities were recorded at monthly intervals in each location from March 2018 to February 2020. The association between weather variables and sand fly densities was analysed using a two-staged hierarchical procedure; Distributed Lag Non-Linear (DLNM) modelling framework and the DLNM method implemented in the R package dlnm (version number 2.4.6).

Results

Moderate rainfall values up to 120 mm per month and increasing RH up to 82 at lag of 0 months along with increasing soil temperature and evaporation rate at lag of 2 months were associated with statistically significant increase in the sand fly activity. These associations were heterogeneous across study settings. Whereas increasing ambient and soil temperature, sunshine hours, evaporation rate appeared to reduce the sand fly activity homogeneously at lag of 0 month in all the study settings.

Conclusions

The abundance of sand fly vectors varied in relation to selected climatic variables, either in real-time or with a time lag. This information can be utilized for predicting sand fly densities and for the development of effective strategies to prevent leishmaniasis transmission in specific settings.

Transparent Figures: Researching and Preserving Objects of Cellulose Acetate

In 1935, the Deutsches Hygiene-Museum Dresden began to produce the so-called Transparent Figures, which became icons of the 20th century. This study aims to explore the effects of external agents such as humidity and temperature on the aging mechanism of the materials of the Transparent Figures and to slow it down through preventive measures. The focus is on cellulose acetate (CA), which was used for the outer skin of the Transparent Figures. The original objects were investigated using FTIR, Raman, and GC-MS. On some Transparent Figures, liquid leakage of additives occurs when the relative humidity rises above 50-60% RH and is accompanied by a release of acetic acid. Based on these findings, original CA used for the production of the Transparent Figures was artificially re-aged at 70 °C while varying the relative humidity. The specimens were analyzed with colorimetry and GC-MS. Additive content, degree of substitution and degree of polymerization were determined. The results showed that the degradation is slowed down at 30% RH compared to aging at 50% RH or 70% RH. Thus, lowering the relative humidity seems effective in slowing down the degradation of the CA of the Transparent Figures. A relative humidity of 30% RH and a temperature of 15 °C are recommended.

Miyeokgui (Undaria pinnatifida Sporophyll) Characteristic under Different Relative Humidity: Microbial Safety, Antioxidant Activity, Ascorbic Acid, Fucoxanthin, α-/β-/γ-Tocopherol Contents

This study aimed to investigate the effects of different relative humidities (%) on the microbial safety, antioxidant activity, ascorbic acid, fucoxanthin, and tocopherol contents of Undaria pinnatifida sporophyll powder (UPSP) stored for 4 weeks. The caking phenomenon did not occur in the 11-53% relative humidity conditions, but it did in the 69%, 81%, and 93% relative humidity conditions with caking index values of 88.30%, 99.75%, and 99.98%, respectively. The aerobic bacterial contents increased drastically in samples stored at 69-93% relative humidity. Ascorbic acid was unstable at high relative humidity, but fucoxanthin and tocopherol were more unstable at low relative humidity. Therefore, it was most stable at intermediate relative humidity. The 69% relative humidity sample had higher DPPH (12.57 g BHAE/kg), ABTS (4.87 g AAE/kg), and FRAP (4.60 g Fe (II)/kg) than the other samples. This study could be helpful for the storage and transport of UPSP under optimum relative humidity conditions, which can significantly prevent quality losses.

Competitive and Cooperative CO2-H2O Adsorption through Humidity Control in a Polyimide Covalent Organic Framework

In order to capture and separate CO₂ from the air or flue gas streams through nanoporous adsorbents, the influence of the humidity in these streams has to be taken into account as it hampers the capture process in two main ways: (1) water preferentially binds to CO₂ adsorption sites and lowers the overall capacity, and (2) water causes hydrolytic degradation and pore collapse of the porous framework. Here, we have used a water-stable polyimide covalent organic framework (COF) in N₂/CO₂/H₂O breakthrough studies and assessed its performance under varying levels of relative humidity (RH). We discovered that at limited relative humidity, the competitive binding of H₂O over CO₂ is replaced by cooperative adsorption. For some conditions, the CO₂ capacity was significantly higher under humid versus dry conditions (e.g., a 25% capacity increase at 343 K and 10% RH). These results in combination with FT-IR studies on equilibrated COFs at controlled RH values allowed us to assign the effect of cooperative adsorption to CO₂ being adsorbed on single-site adsorbed water. Additionally, once water cluster formation sets in, loss of CO₂ capacity is inevitable. Finally, the polyimide COF used in this research retained performance after a total exposure time of >75 h and temperatures up to 403 K. This research provides insight in how cooperative CO₂-H₂O can be achieved and as such provides directions for the development of CO₂ physisorbents that can function in humid streams.

Aerial roots elevate indoor plant health: Physiological and morphological responses of three high-humidity adapted Araceae species to indoor humidity levels

Heightened by the COVID-19 pandemic there has been a global increase in urban greenspace appreciation. Indoor plants are equally important for improving mental health and air quality but despite evolving in humid (sub)tropical environments with aerial root types, planting systems ignore aerial resource supply. This study directly compared nutrient uptake preferences of aerial and soil-formed roots of three common houseplant species under high and ambient relative humidities. Growth and physiology parameters were measured weekly for Anthurium andreanum, Epipremnum aureum and Philodendron scandens grown in custom made growth chambers. Both aerial and soil-formed roots were then fed mixtures of nitrate, ammonium and glycine, with one source labelled with ¹⁵ N to determine uptake rates and maximum capacities. Aerial roots were consistently better at nitrogen uptake than soil roots but no species, root type or humidity condition showed a preference for a particular nitrogen source. All three species grew more in high humidity, with aerial roots demonstrating the greatest biomass increase. Higher humidities for indoor niches, together with fertiliser applications to aerial roots will support indoor plant growth, creating lush calming indoor environments for people inhabitants.

Beyond the usual climate? Factors determining flowering and fruiting phenology across a genus over 117 years

PREMISE

Although changes in plant phenology are largely attributed to changes in climate, the roles of other factors, such as genetic constraints, competition, and self-compatibility, are underexplored.

METHODS

We compiled >900 herbarium records spanning 117 years for all 8 nominal species of the winter-annual genus Leavenworthia (Brassicaceae). We used linear regression to determine the rate of phenological change across years and phenological sensitivity to climate. Using a variance partitioning analysis, we assessed the relative influence of climatic and non-climatic factors (self-compatibility, range overlap, latitude, and year) on Leavenworthia reproductive phenology.

KEY RESULTS

Flowering advanced by ~2.0 days and fruiting ~1.3 days per decade. For every 1°C increase in spring temperature, flowering advanced ~2.3 days and fruiting ~3.3 days. For every 100 mm decrease in spring precipitation, each advanced ~6-7 days. The best models explained 35.4% of flowering variance and 33.9% of fruiting. Spring precipitation accounted for 51.3% of explained variance in flowering date and 44.6% in fruiting. Mean spring temperature accounted for 10.6% and 19.3%, respectively. Year accounted for 16.6% of flowering variance and 5.4% of fruiting, and latitude 2.3% and 15.1%, respectively. Non-climatic variables combined accounted for <11% of the variance across phenophases.

CONCLUSIONS

Spring precipitation, alongside other climate and climatically-related factors, were dominant predictors of phenological variance. Our results emphasize the strong effect of precipitation on phenology, especially in moisture-limited habitats preferred by Leavenworthia. Amongst the many factors that determine phenology, climate is the dominant influence, indicating the effects of climate change on phenology are expected to increase. This article is protected by copyright. All rights reserved.

Viscoelastic Behavior of Supercooled and Glassy ASDs at Humid Conditions Can Be Predicted

Amorphous solid dispersions (ASDs) are commonly used to increase the dissolution rate of poorly soluble active pharmaceutical ingredients (APIs). Unfortunately, most ASDs are thermodynamically unstable and, even though kinetically stabilized, will thus eventually crystallize. The crystallization kinetics is determined by the thermodynamic driving force and by molecular mobility, which in turn depend on the drug load, temperature, and relative humidity (RH) at which the ASDs are stored. This work focuses on viscosity as an indicator for the molecular mobility in ASDs. The viscosity and shear moduli of ASDs consisting of the polymer poly(vinylpyrrolidone-co-vinyl acetate) or hydroxypropyl methylcellulose acetate succinate and the API nifedipine or celecoxib were studied using an oscillatory rheometer. The effects of temperature, drug load, and RH on the viscosity were investigated. With the knowledge of how much water is absorbed by the polymer or ASD and thereby also the knowledge of the glass-transition temperature of the wet polymer or ASD, the viscosity of dry and wet ASDs was predicted to be in very good agreement with experimental data just based on the viscosity of neat polymers and the glass-transition temperatures of wet ASDs.

Influence of Humidity and Heating Rate on the Continuous ZIF Coating during Hydrothermal Growth

Zeolitic imidazolate frameworks (ZIFs) have potential for various gas and ion separations due to their well-defined pore structure and relatively easy fabrication process compared to other metal-organic frameworks and zeolites. As a result, many reports have focused on preparing polycrystalline and continuous ZIF layers on porous supports with good separation performance in various target gases, such as hydrogen extraction and propane/propylene separation. To utilize the separation properties in industry, membrane is required to be prepared in large scale with high reproducibility. In this study, we investigated how humidity and chamber temperature influence the structure of a ZIF-8 layer prepared by the hydrothermal method. Many synthesis conditions can affect the morphology of polycrystalline ZIF membranes, and previous studies have mainly focused on reaction solutions, such as precursor molar ratio, concentration, temperature, and growth time. On the other hand, we found that the humidity of the chamber and the heating rate of the solution also lead to dramatic changes in the morphology of ZIF membranes. To analyze the trend between humidity and chamber temperature, we set up the chamber temperature (ranging from 50 °C to 70 °C) and relative humidity (ranging from 20% to 100%) using a thermo-hygrostat chamber. We found that as the chamber temperature increased, ZIF-8 preferentially grew into particles rather than forming a continuous polycrystalline layer. By measuring the temperature of the reacting solution based on chamber humidity, we discovered that the heating rate of the reacting solution varied with humidity, even at the same chamber temperature. At a higher humidity, the thermal energy transfer was accelerated as the water vapor delivered more energy to the reacting solution. Therefore, a continuous ZIF-8 layer could be formed more easily at low humidity ranges (ranging from 20% to 40%), while micron ZIF-8 particles were synthesized at a high heating rate. Similarly, under higher temperatures (above 50 °C), the thermal energy transfer was increased, leading to sporadic crystal growth. The observed results were obtained with a controlled molar ratio, in which zinc nitrate hexahydrate and 2-MIM were dissolved in DI water at a molar ratio of 1:45. While the results are limited to these specific growth conditions, our study suggests that controlling the heating rate of the reaction solution is critical for preparing a continuous and large-area ZIF-8 layer, particularly for the future scale-up of ZIF-8 membranes. Additionally, humidity is an important factor in forming the ZIF-8 layer, as the heating rate of the reaction solution can vary even at the same chamber temperature. Further research related to humidity will be necessary for the development of large-area ZIF-8 membranes.

Structural Analysis of Phase Change Materials (PCMs)/Expanded Graphite (EG) Composites and Their Thermal Behavior under Hot and Humid Conditions

Expanded graphite (EG) has been used to store phase change materials (PCM) to enhance thermal conductivity and avoid leakage. However, systematic investigation on physical structure of various embedded PCMs in EG is not reported. Besides, effect of environment on thermal behavior of PCM/EG composites has not been investigated yet. In this work, three common PCMs were used to be embedded in EG and three PCM/EG composites were obtained, including myristic acid (MA), polyethylene glycol (PEG) and paraffin wax (PW). As a result, capillary force between EG and PCMs supported encapsulation of PCMs in EG. PCM/EG composites had narrower phase change range while supercooling degree values were different when various PCMs were used. Besides, the hot and humid environment had a side effect on thermal energy storage of PCMs and PCM/EG composites. The inherent hydrophilicity of PCMs was essential for resistance against side effect of moisture on thermal energy storage.

Influence of Hospital Environmental Variables on Thermometric Measurements and Level of Concordance: A Cross-Sectional Descriptive Study

During a pandemic, and given the need to quickly screen febrile and non-febrile humans, it is necessary to know the concordance between different thermometers (TMs) and understand how environmental factors influence the measurements made by these instruments.

OBJECTIVE

The objective of this study is to identify the potential influence of environmental factors on the measurements made by four different TMs and the concordance between these instruments in a hospital setting.

METHOD

The study employed a cross-sectional observational methodology. The participants were patients who had been hospitalised in the traumatology unit. The variables were body temperature, room temperature, room relative humidity, light, and noise. The instruments used were a Non Contract Infrared TM, Axillary Electronic TM, Gallium TM, and Tympanic TM. A lux meter, a sound level meter, and a thermohygrometer measured the ambient variables.

RESULTS

The study sample included 288 participants. Weak significant relationships were found between noise and body temperature measured with Tympanic Infrared TM, r = -0.146 (p < 0.01) and likewise between environmental temperature and this same TM, r = 0.133 (p < 0.05). The concordance between the measurements made by the four different TMs showed an Intraclass Correlation Coefficient (ICC) of 0.479.

CONCLUSIONS

The concordance between the four TMs was considered "fair".

Long-term monitoring of Mount St. Helens micrometeorology

The 1980 volcanic eruption of Mount St. Helens had profound impacts on the geology, hydrology, and ecology of its surrounding landscapes. Consequently, the event provided a unique opportunity to study ecological change over time in relation to abiotic factors. To better assess the role localized environmental conditions play in these larger processes, we have monitored micrometeorological conditions across six disturbance zones on Mount St. Helens created by the eruption. We deployed 823 environmental sensors at 191 sites from 1997 to 2022 to measure the temperature and relative humidity of aquatic (temperature only) and terrestrial habitats in these areas, collecting over 4.2 million measurements in total. Measurements were typically recorded every 30 min from late spring through mid-fall, with the exception being Spirit Lake, where temperatures have been measured hourly on a year-round basis since 2002. These data have been used to address two broad research questions: (1) how small-scale environmental conditions influence patterns of survivorship and/or establishment on Mount St. Helens post-eruption for a range of organisms, including plants, small mammals, birds, amphibians, arthropods, fish, and other aquatic biota, and (2) to quantify and compare these environmental conditions across different disturbance zones, which vary in disturbance type, intensity, and history of post-eruption secondary disturbances. Due to the repeatability of these measurements over many years, these data lend themselves to exploring the relationship between forest succession and microclimate, especially with respect to forest-dwelling organisms whose spread and demography are sensitive to temperature and relative humidity. In addition, this dataset could be used to investigate additional questions related to early succession, disturbance ecology, climate change, or volcano ecology. This dataset is available in the R data package MSHMicroMetR, which also includes an R Shiny data visualization and exploration tool. There is no copyright on the data; please cite this data paper Ecology when using these data.

Influence of Operating and Electrochemical Parameters on PEMFC Performance: A Simulation Study

Proton exchange membrane fuel cell, or polymer electrolyte fuel cell, (PEMFC) has received a significant amount of attention for green energy applications due to its low carbon emission and less other toxic pollution capacity. Herein, we develop a three-dimensional (3D) computational fluid dynamic model. The values of temperature, pressure, relative humidity, exchange coefficient, reference current density (RCD), and porosity values of the gas diffusion layer (GDL) were taken from the published literature. The results demonstrate that the performance of the cell is improved by modifying temperature and operating pressure. Current density is shown to degrade with the rising temperature as explored in this study. The findings show that at 353 K, the current density decreases by 28% compared to that at 323 K. In contrast, studies have shown that totally humidified gas passing through the gas channel results in a 10% higher current density yield, and that an evaluation of a 19% higher RCD value results in a similar current density yield.

SARS-CoV-2 persistence on common food covering materials: plastic wrap, fruit wax, and cardboard takeout containers

AIMS

Assess the persistence of infectious SARS-CoV-2 virus and virus genomic material on three common food coverings.

METHODS AND RESULTS

The stability of infectious virus and genomic material on plastic wrap, fruit wax, and cardboard takeout containers was measured. SARS-CoV-2 in simulated saliva was applied to the surface of these materials and allowed to dry. Samples were stored at 4°C or 20°C and a relative humidity of 30%, 50%, 65%, or 70% for up to 7 days. Viability was measured by TCID50 and the half-life for infectious virus was determined to be ~24 hours and ~8 hours at 4°C and 20°C, respectively, on all surfaces and RH tested. There was no loss of virus genomic material as measured by qRT-PCR at all conditions evaluated.

CONCLUSIONS

SARS-CoV-2 virus remains infectious on food coverings for hours to days. It is estimated that a 99.9% reduction in titer requires 10 days at 4°C and 3 days at 20°C for all RH tested. SARS-CoV-2 genomic material showed no loss when assayed by qRT-PCR. Significance and Impact of Study: SARS-CoV-2 virus on food coverings loses infectivity over a certain period, but PCR assays can still detect virus genomic material throughout the same time. Thus, testing and controls may need to consider the fact that virus genomic material may still be detected when no infectious virus is present.

Molecular Understanding of the Enhancement in Organic Aerosol Mass at High Relative Humidity

The mechanistic pathway by which high relative humidity (RH) affects gas-particle partitioning remains poorly understood, although many studies report increased secondary organic aerosol (SOA) yields at high RH. Here, we use real-time, molecular measurements of both the gas and particle phase to provide a mechanistic understanding of the effect of RH on the partitioning of biogenic oxidized organic molecules (from α-pinene and isoprene) at low temperatures (243 and 263 K) at the CLOUD chamber at CERN. We observe increases in SOA mass of 45 and 85% with increasing RH from 10-20 to 60-80% at 243 and 263 K, respectively, and attribute it to the increased partitioning of semi-volatile compounds. At 263 K, we measure an increase of a factor 2-4 in the concentration of C10H16O2-3, while the particle-phase concentrations of low-volatility species, such as C10H16O6-8, remain almost constant. This results in a substantial shift in the chemical composition and volatility distribution toward less oxygenated and more volatile species at higher RH (e.g., at 263 K, O/C ratio = 0.55 and 0.40, at RH = 10 and 80%, respectively). By modeling particle growth using an aerosol growth model, which accounts for kinetic limitations, we can explain the enhancement in the semi-volatile fraction through the complementary effect of decreased compound activity and increased bulk-phase diffusivity. Our results highlight the importance of particle water content as a diluting agent and a plasticizer for organic aerosol growth.

A Synergistic Approach to Atmospheric Water Scavenging

An abundant supply of fresh water is one of the leading challenges of the 21st century (UNESCO. The United Nations World Water Development Report 2018: Nature-Based Solutions for Water;UNESCO: Paris, France, 2018; p 154). Here we describe a new approach to scavenge atmospheric water that employs a hierarchically ordered porous material with embedded particles (Lash, M. H.; Jordan, J. C.; Blevins, L. C.; Fedorchak, M. V.; Little, S. R.; McCarthy, J. J.Non-Brownian Particle-Based Materials with Microscale and Nanoscale Hierarchy. Ang. Chem. Int. Ed.201554, 5854-5858). This composite uses structure to amplify native material performance to realize synergy between the capture and storage and to ultimately qualitatively change the adsorption behavior of the hydrogel (from unfavorable to favorable). In this way we can capture moisture at significantly lower relative humidities than would otherwise be feasible with the native materials. Not only does this approach pose the potential for a cheap and low-energy source of clean water but it could also be modified for application across a variety of condensable vapor reclamations.

Effect of temperature and humidity on dynamics and transmission of Pseudomonas amygdali pv. lachrymans aerosols

Cucumber angular leaf spot (ALS) disease, caused by Pseudomonas amygdali pv. lachrymans (Pal), is an emerging disease with a high incidence that causes severe damage to cucumber worldwide. Bacterial aerosols play a crucial role in the epidemiology of greenhouse ALS disease. However, little is known about the influence of temperature and relative humidity (RH) on the dynamics of Pal in aerosols. A study was conducted to investigate the relationships between the concentration of Pal aerosols and their dependence on temperature and RH in aerosol chambers and greenhouses. The results demonstrated that temperature and RH are both significant factors influencing the release amount, survival time and infectivity of Pal in aerosols, while RH has a greater influence on particle size than temperature across the range of conditions tested. The release amount and survival time of Pal in aerosols under high RH (95%) and low temperature (≤ 25°C) conditions were significantly higher than those under low RH (35%) and high temperature (35°C) conditions. The highest release amount of Pal aerosol (96 CFU/m³) and highest survival rate (98.41%) were found at 18°C and 95% RH, while the highest disease index (DI = 60.9) caused by Pal aerosol was found at 25°C and 95% RH. In addition, Pal aerosols presented a larger diameter (4.7->7.0 μm) under high RH (95% RH) than under dry conditions (≤ 65% RH). These findings will play a crucial role in elucidating the influence of environmental parameters on the dynamics and transmission of Pal in aerosols. Based on our findings, preliminary recommendations for controlling airborne Pal spread involve controlling air temperature and RH, which will contribute to the effective alleviation and control of cucumber ALS disease.

Sensing Bioavailable Water Content of Granulated Matrices: A Combined Experimental and Computational Study

This paper represents the synthesis, characterization and validation of a cobalt chloride functionalised nano-porous cellulose membrane, a unique sensor for non-contact measurement of water potential in various biomedical and environmentally important matrices. The developed nano sensor, along with associated electronic components, is assembled as a prototype device called "MEGH" (Measuring Essential Good Hydration) to measure essential hydration of matrices of both environmental and biomedical importance, including soil and human skin. The relative humidity above the soil surface in equilibrium with the soil moisture has been studied for both hydrophobic and hydrophilic soil types. Our studies confirm that the percentage of water available to plants is greater in hydrophobic soil rather than in hydrophilic soil, which has also been corroborated using simulation studies. Furthermore, the requirement of hydration in human skin has also been evaluated by measuring the water potential of both dry and moist skin.

Association between Meteorological Factors and Outpatient Visits for Herpes Zoster in Hefei, China: A Time-Series Analysis

This study sought to investigate the relationship between meteorological factors and outpatient visits for herpes zoster. In this time-series analysis, we used data from two major hospitals in Hefei, collected between 2015 and 2019, to evaluate the impact of meteorological factors on the risk of herpes zoster. After controlling for confounders, we adopted a distributed lag nonlinear model to probe the relationship between meteorological factors and outpatient visits for herpes zoster. The analysis was stratified according to age (<40 years, ≥40 years) and sex (male, female). A total of 43,547 cases of herpes zoster were reported, and compared with the median value, a high temperature and high relative humidity had a significant risk effect on the incidence of herpes zoster. The maximum harmful effect of high temperature on herpes zoster occurred on the lag0 (RR: 1.027, 95% CI: 1.002-1.053) and further declined over the following days. The cumulative effect increased with the extension of lag days, and the cumulative RR was the largest on the sixth day of lag (RR1.031, 95% CI: 1.006-1.056) when the relative humidity was 85.7% (77.0% as the reference). The stratified analysis results reveal that females and the elderly (≥40 years) were more susceptible to temperature and relative humidity. This study shows that high-temperatures may lead to herpes zoster, indicating that those infected with varicella zoster virus need to take measures over the course of several days when not exposed to the best appropriate temperature conditions.

Effects of Ambient Temperature and Humidity on Natural Deposition Characteristics of Airborne Biomass Particles

In the production process of biomass energy with crop straw as the raw material, the indoor dust environment created by smashed plant fiber can affect the health of workers and lead to the risk of fire and explosions. The physical properties of biomass vary with the ambient air conditions, resulting in different deposition processes for airborne biomass particles. In this study, the deposition of biomass particles in different environments in an experimental chamber was examined by independently controlling the internal temperature and relative humidity. The results show that in the ambient temperature range of 20~40 °C and at a relative humidity of 25~65%, the water absorption rates of the biomass particles were 15.4~24.7%. The deposition rates of the airborne biomass particles with different sizes were 0.9~2.9 h^-1, which positively correlated with the particle sizes in the same ambient conditions. The increase in ambient temperature and relative humidity promoted the deposition of biomass particles with diameters over 0.5 μm. For the particles with diameters below 0.5 μm, the deposition rates were nonlinearly related to the ambient temperature and relative humidity and were greater at lower temperatures. The significance levels of the factors influencing the particle deposition were particle size > ambient temperature > ambient relative humidity. For the biomass particles below 0.5 μm, the influence of the relative humidity on the deposition was much weaker than that of the temperature.

Influence of Air Humidity Level on the Structure and Mechanical Properties of Thermoplastic Starch-Montmorillonite Nanocomposite during Storage

Thermoplastic starch (TPS) consisting of corn starch and glycerol as a plasticizer, and TPS-montmorillonite (MMT) nanocomposite were stored at room temperature in the air with relative humidities (RH) of 11, 55 and 85% for seven weeks. Mechanical testing and dynamic mechanical thermal analysis (DMTA) were performed to detect changes in their mechanical properties. Solid-state NMR spectroscopy monitoring the changes in molecular mobility in the samples provided an insight into relations between mechanical properties and local structure. The results of mechanical testing indicated that the addition of MMT results in the increase in the tensile strength and Young's modulus while elongation at break decreased, indicating the reinforcing effect of MMT. DMTA experiments revealed a decrease in glass transition temperature of starch-rich phase below room temperature for samples stored at higher RH (55 and 85%). This indicates that absorbed water molecules had additional plasticizing effect on starch resulting in higher mobility of starch chain segments. Recrystallization in these samples was deduced from the shape of cross-polarization magic-angle spinning ¹³C NMR spectra. The shape of broad-line ¹H NMR spectra reflected changes in molecular mobility in the studied samples during seven weeks of storage and revealed that a high amount of water molecules impacts the starch intermolecular hydrogen bond density.

Influences of temperature and humidity on cardiovascular disease among adults 65 years and older in China

Background

The burden of cardiovascular disease (CVD) on the current aging society in China is substantial. Climate change, including extreme temperatures and humidity, has a detrimental influence on health. However, epidemiological studies have been unable to fully identify the association between climate change and CVD among older adults. Therefore, we investigated the associations between temperature and relative humidity and CVD among older adults in China.

Methods

We used cohort data from the China Longitudinal Health and Longevity Survey (CLHLS) conducted in 2002, 2005, 2008, 2011, 2014, and 2018. A total of 39,278 Chinese adults 65 years and older participated in the analyses. The average annual temperatures and relative humidity during 2001 and 2017 (before the survey year) at the city level in China were used as the exposure measures. We selected patients with hypertension, heart disease, and stroke to create a sample of CVD patients. The associations between temperature and relative humidity and CVD were analyzed using the generalized estimation equation (GEE) model. Covariates included sociodemographic factors, health status, lifestyle, and cognitive function.

Results

The average annual temperature was negatively correlated with the prevalence of CVD. Every 1°C increase in the average annual temperature reduced the rates of hypertension by 3% [odds ratio (OR): 0.97; 95% confidence interval (CI): 0.96-0.97], heart disease by 6% (OR: 0.94; 95% CI: 0.92-0.95), and stroke by 5% (OR: 0.95; 95% CI: 0.94-0.97). The results of the analyses stratified by sex, urban/rural residence, and educational level were robust. The average annual relative humidity was inversely associated with the likelihood of CVD among older adults. Every 1% increase in the average annual relative humidity reduced the rates of hypertension by 0.4% (OR: 0.996; 95% CI: 0.99-1.00), heart disease by 0.6% (OR: 0.994; 95% CI: 0.99-1.00), and stroke by 0.08% (OR: 0.992; 95% CI: 0.98-1.00). However, the effects were more obvious with higher humidity levels (>70).

Conclusion

Our findings suggest that higher temperatures and relative humidity may reduce the risk of CVD among older adults.