Elevated Humidity Research Articles

Effect of polyvinylpyrrolidone and lithium chloride composite desiccant-coated heat exchangers on dehumidification studies

Cooling systems are necessities that remain energy intensive, particularly in tropical regions with elevated humidities and temperatures. Conventional vapor-compression air-conditioners are often inefficient because the sensible and latent heat loads are intrinsically coupled. To realize more energy-efficient cooling, solid desiccant-coated devices can be introduced to mitigate the latent heat load. Among such devices, desiccant-coated heat exchangers (DCHEs) are attractive for enabling nearly isothermal dehumidification. Hence, desiccants with high sorption capacity and rapid kinetics are essential. Solid polymeric desiccants are well-positioned to meet these requirements but comprehensive studies on the dehumidification performance of solid polymeric desiccant-coated heat exchangers are currently lacking. In this study, we investigated the potential of polyvinylpyrrolidone (PVP) and lithium chloride (LiCl) composites as desiccant materials at both material and system levels in terms of gravimetric water uptake. Specifically, LiCl is a hygroscopic salt bound by the moisture-sorbing PVP matrix. This work also demonstrates how the Elovich model accurately predicted the PVP-LiCl composite’s sorption kinetics. The results show that the optimum PVP-LiCl composite ratio is 66.7 wt%, with an equilibrium sorption capacity of 280 % at 75 % RH and 25 °C, compared to 29 % for silica gel under the same condition. With much superior sorption kinetics and capacity, the PVP-LiCl-coated prototype heat exchanger demonstrated a moisture removal capacity eight times higher than a silica gel-coated one under dynamic flow towards energy savings in air-conditioning systems.

Assessing Change Impacts on Flood and Drought hazard in Thua Thien Hue province using Standardized Precipitation Index (SPI)

The objective of this study is to comprehensively analyze short- and long-term drought and flood occurrences, providing valuable insights into the potential impact of climate change in the future. Our analysis, utilizing the SPI-6 and SPI-12 indices, focuses on historical data spanning from 1979 to 2019, revealing noteworthy patterns. Notable periods of severe drought include September 1982 to August 1983, September 2004 to August 2005, and October 2014 to August 2015. Conversely, instances of elevated humidity and extreme inundation were recorded from October 1980 to August 1981, October 1995 to June 1997, November 1999 to October 2000, November 2007 to October 2008, October 2011 to August 2012, and January 2017 to August 2018. These findings are consistent with historical records of drought and flood events in Thua Thien Hue Province over the past four decades. Incorporating the SPI-6 and SPI-12 indices alongside rainfall forecasts based on updated climate change and sea-level rise scenarios for 2020 in Vietnam, our study extends its projections to the period from 2020 to 2035. These projections indicate a significant departure from typical annual conditions, with both the severity and frequency of drought and flood events expected to increase. Specifically, Thua Thien Hue weather stations estimate a flood frequency of 14% (SPI-12) and 16% (SPI-6), equivalent to approximately one dry month every seven months. High humidity events are projected to occur at an 18% frequency, roughly once every 5-6 months. Analysis of future scenarios under RCP4.5 and RCP8.5 reveals varying levels of risk associated with drought and flood occurrences. Generally, the risk of flooding is slightly lower than that of drought, with only marginal differences observed in scenario RCP8.5. When considering seasonal rainfall patterns—where half of the year experiences a dry season and the other half is rainy—the incidence of drought surpasses that of high humidity in scenario RCP4.5. In contrast, in scenario RCP8.5, the likelihood of flooding outweighs that of drought. It’s noteworthy that historically, mountainous areas within Thua Thien Hue Province have experienced fewer droughts in comparison to coastal regions. Furthermore, the severity of drought and flood events is more pronounced in scenario RCP8.5, particularly concerning flood events. This underscores that despite higher total rainfall in RCP8.5, leading to more severe inundation events, the distribution exhibits unevenness marked by extreme conditions, including more severe drought events.

Dysnatremia in a changing climate: A global systematic review of the association between serum sodium and ambient temperature.

Both hyponatremia and hypernatremia have been reported to occur more frequently with higher ambient temperatures, although the underlying mechanisms are not well understood. Global temperatures are rising due to climate change, which may impact the incidence of dysnatremia worldwide. We aimed to identify, collate and critically appraise studies analyzing the relationship between climate measures (outdoor temperature, humidity) and serum sodium concentrations. Systematic review, reported in accordance with PRISMA guidelines. MEDLINE and Embase were searched with relevant key terms. Studies assessing the effect on serum sodium measurement of elevated temperature or humidity versus a comparator were included. Of 1466 potentially relevant studies, 34 met inclusion criteria, originating from 23 countries spanning all inhabited continents. The majority (30 of 34, 88%) reported a significant association between outdoor temperature and dysnatremia, predominantly lower serum sodium with increased ambient temperature. Humidity had a less consistent effect. Individuals aged above 65 years, children, those taking diuretics and antidepressants, those with chronic renal impairment or those undertaking physical exertion had increased vulnerability to heat-associated dysnatremia. The risk of bias was assessed to be high in all but four studies. Higher ambient temperature is consistently associated with an increased incidence of hyponatremia. We infer that hyponatremia presentations are likely to rise with increasing global temperatures and the frequency of extreme heat events secondary to climate change. Evidence-based public health messages, clinician education and reduction in fossil fuel consumption are necessary to reduce the expected burden on healthcare services worldwide.

Growth responses to elevated environmental humidity vary between phenological forms of Picea abies

Growth responses to elevated environmental humidity vary between phenological forms of Picea abies

Environmental fatigue crack growth of PV glass/EVA laminates in the melting range

AbstractThe delamination of encapsulants in photovoltaic (PV) modules is a common issue that leads to power loss due to optical losses. Encapsulant debonding is usually examined under monotonic loading conditions subsequent to environmental exposure such as damp heat. Service‐relevant, superimposed environmental‐mechanical fatigue loads are not considered adequately. Hence, the environmental fatigue delamination resistance of thermally toughened double glass laminates with an ethylene vinyl acetate copolymer (EVA) adhesive layer was investigated in this study. Focus was given to the melting range of EVA, in which the non‐crosslinked crystalline phase fraction is already in the partly molten state. Double cantilever beam specimens were tested on an electrodynamic test machine at temperatures of 60, 70, 80, and 90°C and relative humidity (rh) levels of 2%, 30%, 50%, and 80%. The fractured surfaces were characterized by digital microscopy, Fourier transform infrared spectroscopy (FTIR), X‐ray photoelectron spectroscopy (XPS), and differential scanning calorimetry (DSC). The cyclic fatigue tests revealed a decay in delamination resistance at elevated temperature and humidity levels. At 70°C, the delamination resistance was low, regardless of the relative humidity. Most of the laminates failed by debonding. XPS analysis showed a reduction of the C=O and C–O content, along with an increase in Si–O content with increasing relative humidity. For laminates tested at 60 and 70°C, an EVA recrystallization peak was observed in DSC experiments. This peak was shifted to significantly higher temperatures at 80% rh. XPS and DSC indicated local hydrolysis within the porous fracture process zone ahead of the crack tip. Consequently, acetic acid formation led to a decrease in delamination resistance, resulting in lower fatigue threshold values. The investigations confirmed the significant impact of environmental conditions on the fatigue delamination resistance within glass/encapsulant laminates. Notably, acetic acid formation and a significant reduction in delamination properties were observed after around 100 h of environmental fatigue exposure.

Chemiresistive Sensor for Enhanced CO2 Gas Monitoring.

Carbon dioxide (CO2) gas sensing and monitoring have gained prominence for applications such as smart food packaging, environmental monitoring of greenhouse gases, and medical diagnostic tests. Although CO2 sensors based on metal oxide semiconductors are readily available, they often suffer from limitations such as high operating temperatures (>250 °C), limited response at elevated humidity levels (>60% RH), bulkiness, and limited selectivity. In this study, we designed a chemiresistive sensor for CO2 detection to overcome these problems. The sensing material of this sensor consists of a CO2 switchable polymer based on N-3-(dimethylamino)propyl methacrylamide (DMAPMAm) and methoxyethyl methacrylate (MEMA) [P(D-co-M)], and diethylamine. The designed sensor has a detection range for CO2 between 103 and 106 ppm even at high humidity levels (>80% RH), and it is capable of differentiating ammonia at low concentrations (0.1-5 ppm) from CO2. The addition of diethylamine improved sensor performance such as selectivity, response/recovery time, and long-term stability. These data demonstrate the potential of using this sensor for the detection of food spoilage.

Hydrolysis of Cellulose Acetate Phthalate and Hydroxypropyl Methylcellulose Phthalate in Amorphous Solid Dispersions

The preparation of amorphous solid dispersions (ASDs) represents a promising strategy for addressing the solubility limitations of poorly soluble drugs, facilitating enhanced absorption. Acidic polymers such as cellulose acetate phthalate (CAP) and hydroxypropyl methylcellulose phthalate (HPMCP) have emerged as effective carriers for ASDs. Although the hydrolytic degradation of these polymers has been documented, its impact on the stability of ASDs has not been systematically investigated. This research aimed to explore the potential hydrolysis of CAP and HPMCP and how it influences the stability of ASDs containing ketoconazole (KTZ), at drug loadings of 10 % and 50 %. Our study utilized thermal analysis, infrared spectroscopy, and evaluations of physical and chemical stability. The results revealed that although KTZ remained physically stable in all ASDs over a 60-day period under various stability conditions, the emergence of crystalline phthalic acid (PA), a byproduct of polymer hydrolysis, was observed at elevated temperatures and relative humidity levels. The acidic microenvironment fostered by the release of PA further catalyzed drug chemical degradation. This study underscores the susceptibility of CAP and HPMCP to hydrolytic degradation, highlighting the inherent risk of PA-induced drug degradation, particularly for acid-labile compounds. These insights into the understanding of polymer hydrolysis in ASDs pave the way for the development of targeted approaches to safeguard drug stability and optimize pharmaceutical formulations for enhanced bioavailability, efficacy, and safety.

Experimental study of relative humidity absorbed through capillarity of building material under isothermal conditions: Clay-Kaolin reinforced with Alfa fibers

The research article aims to investigate the hygroscopic behavior of water absorbed by capillarity in clay supplemented with Alfa fibers. This specific clay-fiber composite holds significant importance in Moroccan construction practices. The primary aim is to enhance comprehension and control over the material's hydrothermal behavior by investigating moisture absorption traits, responses to varying humidity and temperature conditions, and the influence of fiber reinforcement on moisture equilibrium and structural stability. As temperature levels rise, the equilibrium water content absorbed through capillarity demonstrates a downward trend. The introduction of Kaolin-Alfa fibers into the clay composite profoundly affects the pace at which equilibrium moisture content is lost. This attribute effectively mitigates the likelihood of cracks developing in earthen structures during the drying phase, as it uniformly disperses tensions resulting from shrinkage. The findings showed that by understanding its unique region, Predictions regarding the sorption tendencies of other building materials are possible because of the approximate estimation of Clay-Kaolin reinforced with Alfa fibers sorption behavior. Surface flaws arise on Clay-Kaolin reinforced with Alfa fibers as a result of rising average pore radius and spreading pressure brought on by rising temperature and relative humidity. Furthermore, the heightened average pore volume observed in regions characterized by elevated relative humidity levels precipitates various defects within building materials, a phenomenon that has a discernible impact on their durability.

Aging properties of a vegetable‐based polyurethane foam under high relative humidity and different temperatures

AbstractThe objective of this study is to assess, characterize, and forecast the aging effects on the mechanical properties of a vegetable‐based polyurethane foam (PUF) derived from castor oil under elevated relative humidity conditions and at two distinct load orientations (aligned with the expansion direction and perpendicular to it). Ten specimens were subjected to temperatures of 60, 75, and 90°C, along with a relative humidity of 90%, for a duration of up to 60 days. Compression tests, following ASTM D1621‐16 standards and supplemented by 3D digital image correlation, revealed nearly isotropic behavior with marginally lower compression strength in the expansion direction. On the other hand, the strength of the foams at 90°C was higher in that direction. This led to a smaller activation energy (Ea) in this property, which ended up showing a shorter lifespan prediction considering the strength retention in this direction. The stiffness values were proportionally more similar in both directions than the strength ones and this was observed in the Ea for those curves. In contrast to several other foams and polyurethanes, the one examined in this study exhibited consistently higher Ea values for its mechanical properties, particularly in the transverse direction to expansion, surpassing 94 kJ/mol. This indicates a robust diffusion and chemical stability, suggesting its potential for prolonged utilization compared to conventional oil‐based foams. A prediction was made that this foam would lose 50% of its stiffness and strength in around 9.8 and 9.5 years at 20°C, respectively, considering the directions more sensitive to the aging process. This research offers valuable insights for predicting lifespan based on operating temperatures and property retention needs, contributing to the advancement of sustainable materials in structural applications.Highlights Fifty specimens investigated for each of two directions. Evaluation of vegetable‐based PUF aging process unveils density changes. Unique behavior noted: different Ea values for each direction. High Ea values indicate enhanced mechanical stability over oil‐based foams. Lifespan prediction enhances material application prospects.

Evolution of avian heat tolerance: The role of atmospheric humidity.

The role of atmospheric humidity in the evolution of endotherms' thermoregulatory performance remains largely unexplored, despite the fact that elevated humidity is known to impede evaporative cooling capacity. Using a phylogenetically informed comparative framework, we tested the hypothesis that pronounced hyperthermia tolerance among birds occupying humid lowlands evolved to reduce the impact of humidity-impeded scope for evaporative heat dissipation by comparing heat tolerance limits (HTLs; maximum tolerable air temperature), maximum body temperatures (Tbmax), and associated thermoregulatory variables in humid (19.2 g H2O m-3) versus dry (1.1 g H2O m-3) air among 30 species from three climatically distinct sites (arid, mesic montane, and humid lowland). Humidity-associated decreases in evaporative water loss and resting metabolic rate were 27%-38% and 21%-27%, respectively, and did not differ significantly between sites. Decreases in HTLs were significantly larger among arid-zone (mean ± SD = 3.13 ± 1.12°C) and montane species (2.44 ± 1.0°C) compared to lowland species (1.23 ± 1.34°C), with more pronounced hyperthermia among lowland (Tbmax = 46.26 ± 0.48°C) and montane birds (Tbmax = 46.19 ± 0.92°C) compared to arid-zone species (45.23 ± 0.24°C). Our findings reveal a functional link between facultative hyperthermia and humidity-related constraints on evaporative cooling, providing novel insights into how hygric and thermal environments interact to constrain avian performance during hot weather. Moreover, the macrophysiological patterns we report provide further support for the concept of a continuum from thermal specialization to thermal generalization among endotherms, with adaptive variation in body temperature correlated with prevailing climatic conditions.

Impacts of Northward Typhoons on Autumn Haze Pollution Over North China Plain

AbstractAlthough air quality in China has improved substantially over recent years, haze pollution events still occur frequently, especially over the North China Plain (NCP). Previous studies showed that typhoons are conducive to regional pollution events in eastern China; however, the underlying mechanism and quantitative understanding of the typhoons' impact on haze pollution remain unclear there. Here, based on ground‐based and satellite observations, reanalysis data, and model simulations, we show that northward typhoons approaching China are essential for autumn haze pollution over NCP. Elevated relative humidity levels and enhanced pollution accumulation, caused by northward typhoons and the corresponding high‐pressure systems, are responsible for the pollution enhancements over NCP. Compared with episodes without typhoon influence, cities near Taihang and Yan Mountain suffer from heavier haze pollution when typhoons approach, with PM2.5 concentrations increasing from 87.1 to 106.4 μg m−3. More water vapor from the Yellow and Bohai Seas and pollutants from eastern China are transported to these cities by typhoon‐induced southeasterly wind anomalies, facilitating the chemical formation of aerosols there. In addition, by the block of mountains, these southeasterly wind anomalies also lead to stronger local accumulation over cities and an elevation of pollutants along the mountains. What is more, with the implementation of emission reduction, the relative changes of PM2.5 concentrations between typhoon‐induced episodes and no‐typhoon episodes increase. This work highlights the importance of understanding the impact of synoptical weather on PM2.5 transport, accumulation, and formation processes in haze pollution mitigation in eastern China.

Compatibility study of formoterol fumarate-lactose dry powder inhalation formulations: Spray drying, physical mixture and commercial DPIs

Formoterol fumarate (FF) is a long-acting beta-adrenergic receptor agonist that is administered as a dry powder inhaler (DPI) for chronic respiratory conditions. In most DPI formulations, the drug substance and the carrier are the two major components. Lactose is the most common carrier, which can undergo a Maillard reaction in the presence of primary and secondary amines. FF contains a secondary amine. Since the potential for Maillard reaction in DPI formulations has not been investigated yet, this study aims to investigate any potential reaction between lactose and FF. The formulations were prepared using a tubular mixer and spray drying techniques. FF and lactose were blended using a tubular mixer (TM FF-Lac). In the spray drying method, FF and lactose were dissolved in distilled water: MeOH and then spray dried (SD FF-Lac). The samples were stored at both ambient conditions and elevated temperature and humidity (40 °C ± 2, 75% ± 5 RH), and subsequently analyzed to identify any signs of incompatibilities. Differential scanning calorimetry (DSC), field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), and liquid chromatography-mass spectrometry (LC-MS-MS) were employed for sample analysis. The in vitro aerosolization performance was evaluated using a next-generation impactor (NGI). The results showed that the colour of the DPI formulations changed from white to brown after storage at elevated temperature and humidity. Although the SD FF-Lac had better aerosolization properties, it was more vulnerable to degradation due to its amorphous nature. The FF-lactose adduct was formed in all samples. Interestingly, adduct compounds were also detectable before the storage for stability and stress tests. Incompatibility was confirmed by HPLC-PDA analysis. The mass spectra revealed the m/z of the adduct compound and confirmed the Millard reaction. Browning occurred in the prepared DPI formulations following storage at elevated temperature and humidity. Moreover, adduct compounds were also found in DPI formulations kept at ambient conditions and commercial DPI. Overall, mass spectroscopy was capable of detecting the incompatibility.

Anthropogenic warming degrades spring air quality in Northeast Asia by enhancing atmospheric stability and transboundary transport

Air pollutants can travel long distances from their sources, often causing severe particulate matter (PM) pollution in downwind regions. This transboundary pollution is largely influenced by meteorology and hence its changes associated with climate change. However, the effects of anthropogenic warming on transboundary pollution remain unclear. We show that springtime PM pollution can worsen with anthropogenic warming not only in the upwind region (northern China) but also in the downwind regions (South Korea and southern Japan). The worse air quality in northern China is attributed to a shallower boundary layer due to warmer air advection in the upper levels from high-latitude Eurasia and thus increased atmospheric stability. In the downwind regions, enhanced westerly/southwesterly anomalies induced by anthropogenic warming strengthen transboundary transport. The increase in primary aerosol concentrations due to the shallower boundary layer and/or enhanced transboundary transport is ~14% in northern China, ~13% in South Korea, and ~17% in southern Japan. The elevated relative humidity due to enhanced moisture transport by the wind anomalies promotes secondary aerosol formation, which further degrades the air quality in the downwind regions. The enhancement ratio of secondary aerosols relative to changes in primary aerosols is ~1 in northern China, ~1.12 in South Korea, and ~1.18 in southern Japan due to anthropogenic warming.

Low-resistance and high-tolerance monolithic spiro-bifluorene-based conjugated microporous polymer for co-capture of PM and CO2 in waste gas

The utilization of solid adsorbents for the co-capture of harmful particulate matter (PM) and carbon dioxide (CO2) in industrial exhaust streams represents a crucial component within the emerging field of waste gas terminal treatment technologies. Extensive research has focused on particulate or powdered adsorbents rather than monolithic materials, whereas monolithic adsorbents exhibit superior advantages in practical industrial applications. Herein, a monolithic spiro-bifluorene-based conjugated micro-porous polymer (DS-CMPs) with hierarchical porous and functionalized hollow nanotube structures was proposed. The favorable characteristics exhibited by DS-CMPs encompass a highly delocalized π-π conjugated skeleton, permanent porosity, unique thermal and chemical stability, precisely defined chemical composition, and excellent water vapor tolerance. These inherent qualities guarantee that DS-CMPs employed for the co-capture of PM and CO2 from exhaust gases exhibit exceptional capture efficiency, low permeation resistance, favorable isosteric heat of adsorption (Qst), and recyclability. The reasons behind the high capture efficiency and low permeation resistance of monolithic DS-CMPs were analyzed through mechanistic exploration and Electrostatic Surface Potential (ESP) calculations. Moreover, the stability inherent in the framework structure and physicochemical properties of DS-CMPs can surmount the notable decline in the capturing capability of porous materials utilized within damp and elevated temperature surroundings. Following exposure to elevated humidity (RH = 86 ± 1 %) and high-temperature (500 ℃) conditions, DS-CMPs exhibited a remarkable capture efficiency exceeding 99.00 % for PM2.5. The self-assembly of monolithic DS-CMPs into a smooth array of nanotube bundles effectively reduces the friction between airflow and material, enhances airflow dispersion, and achieves a minimum permeability resistance of only 8 Pa. At a pressure of 1 bar and temperature of 273 K, the CO2 adsorption capacity of DS-CMPs amounts to 2.72 mmol/g. The high absorption capacity for CO2 is primarily attributed to the presence of a significant microporous/mesoporous ratio and notable surface charge differences. In contrast to powdered adsorbents plagued by sample elution and gas pressure drop issues, the monolithic DS-CMPs showcases good mechanical properties, rendering them readily applicable within industrial bed circulation systems to achieve the co-capture of PM and CO2.

The Study of Bluetongue Virus (BTV) and Epizootic Hemorrhagic Disease Virus (EHDV) Circulation and Vectors at the Municipal Parks and Zoobotanical Foundation of Belo Horizonte, Minas Gerais, Brazil (FPMZB-BH).

Bluetongue Virus (BTV) and Epizootic Hemorrhagic Disease Virus (EHDV) are Orbiviruses primarily transmitted by their biological vector, Culicoides spp. Latreille, 1809 (Diptera: Ceratopogonidae). These viruses can infect a diverse range of vertebrate hosts, leading to disease outbreaks in domestic and wild ruminants worldwide. This study, conducted at the Belo Horizonte Municipal Parks and Zoobotany Foundation (FPMZB-BH), Minas Gerais, Brazil, focused on Orbivirus and its vectors. Collections of Culicoides spp. were carried out at the FPMZB-BH from 9 December 2021 to 18 November 2022. A higher prevalence of these insects was observed during the summer months, especially in February. Factors such as elevated temperatures, high humidity, fecal accumulation, and proximity to large animals, like camels and elephants, were associated with increased Culicoides capture. Among the identified Culicoides spp. species, Culicoides insignis Lutz, 1913, constituted 75%, and Culicoides pusillus Lutz, 1913, 6% of the collected midges, both described as competent vectors for Orbivirus transmission. Additionally, a previously unreported species in Minas Gerais, Culicoides debilipalpis Lutz, 1913, was identified, also suspected of being a transmitter of these Orbiviruses. The feeding preferences of some Culicoides species were analyzed, revealing that C. insignis feeds on deer, Red deer (Cervus elaphus) and European fallow deer (Dama dama). Different Culicoides spp. were also identified feeding on humans, raising concerns about the potential transmission of arboviruses at the site. In parallel, 72 serum samples from 14 susceptible species, including various Cervids, collected between 2012 and 2022 from the FPMZB-BH serum bank, underwent Agar Gel Immunodiffusion (AGID) testing for BTV and EHDV. The results showed 75% seropositivity for BTV and 19% for EHDV. Post-testing analysis revealed variations in antibody presence against BTV in a tapir and a fallow deer and against EHDV in a gemsbok across different years. These studies confirm the presence of BTV and EHDV vectors, along with potential virus circulation in the zoo. Consequently, implementing control measures is essential to prevent susceptible species from becoming infected and developing clinical diseases.

Biological and phytochemical variation with pre- and post-harvest conditions for the Acanthus mollis L. leaf

This study investigated for the first time the temporal variation of compounds and biological activities in Acanthus mollis leaves harvested during different seasons. Variables like the harvest date, edaphic-climatic conditions, storage, drying process, and extraction methods can potentially affect phytochemicals content, potentially influencing its safety and efficacy. The study was conducted over two consecutive years, and leaves were harvested at three different vegetative stages: early vegetation, pre-flowering, and flowering. The main non-volatile compounds in the harvested leaves' ethanol extracts were quantified using HPLC-PDA (High-Performance Liquid Chromatography with Photodiode Array Detection). Additionally, the antioxidant capacity of the extracts was evaluated using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. Finally, the anti-inflammatory activity of the extracts on RAW 264.7 murine macrophages stimulated with LPS (lipopolysaccharide) was studied. Phytochemical analysis revealed different compounds crucial for identifying the most favorable harvesting season for Acanthus mollis. These compounds included DIBOA (2,4-dihydroxy-1,4-benzoxazin-3-one), HBOA (2-hydroxy-1,4-benzoxazin-3-one), and verbascoside. The concentration of these compounds varied depending on the vegetative state, with lower levels observed during the flowering season. During the initial vegetation stage, DIBOA emerged as the primary compound, gradually diminishing as the plant advanced through its vegetative state. Notably, the concentrations of both DIBOA and verbascoside exhibited a reverse correlation with temperature, rising as temperatures declined. Under elevated temperatures, humidity, and sun exposure, DIBOA is prone to degradation, while verbascoside, a phenylpropanoid, remains relatively stable in these conditions. It was found that the antioxidant activity of the leaves depends mainly on the amount of verbascoside, while the anti-inflammatory potential is primarily attributed to DIBOA. Verbascoside also showed a protective function against the cytotoxicity of the extracts in this study. Tyrosinase activity was affected by the levels of total benzoxazinoids and phenylpropanoids. Overall, this study elucidates the temporal variation of compounds in Acanthus mollis leaves harvested during different seasons, highlighting the importance of the quantification of specific compounds, such as DIBOA, HBOA, and verbascoside, for the selection of the most favorable harvesting season, and providing insights into the effects of temperature and environmental factors on the concentration of these compounds as well as their biological activities.

Hygrothermal ageing of dry gelatine adhesive films: Microstructure-property relationships

Gelatine adhesives, also known as animal glues, are collagen-based water-soluble biopolymers derived from vertebrate connective tissues. One of the various fields in which gelatine adhesives are widely used is the conservation of cultural heritage such as decorated furniture and panel paintings. It is observed that, with time, the failure in these objects often occurs along the adhesive bondlines. Given the moisture and temperature sensitivity of these adhesives, obtaining knowledge of their long-term behaviour, when exposed to climate variations, is pivotal. Here, the influence of hygrothermal ageing (exposure to a combination of elevated temperature and relative humidity (RH) cycling) on the microstructure and macroscopic properties of four different types of gelatine adhesives is investigated. These adhesives were selected from different animal origins namely bovine, rabbit, and fish with different Bloom strengths. It was observed that ageing cycles interfere with the most critical structural feature of protein chains namely triple helices. A clear decay in triple helix content at the micro-scale, determined by Differential Scanning Calorimetry (DSC) and X-Ray Diffraction (XRD) techniques, was observed which had implications on the macroscopic properties of these adhesives such as reduction of strain to failure and toughness (strain energy density to failure). The rate of decay in properties was revealed to be the highest in the adhesives with the lowest triple helix content. This study provides a scientific view of microstructure-property relationships in gelatinous adhesives as a function of environmental ageing, and stipulates the underlying mechanism of the degradation of mechanical properties as the loss of structural triple helices, regardless of the animal origin.

Sustainable Approaches to Prolonging Shelf Life in Green Mature Tomato Fruit

Green mature tomato fruits demonstrate better transportability compared to fully matured ones. This approach has the potential to play a significant role in diminishing postharvest losses and enhancing the accessibility of nutritionally rich fruit in developing countries. The instability of electricity and insufficient cold storage facilities is recognized for fading the shelf life of various fruits and vegetables. However, post-harvest interventions, including tomatoes, can extend perishable products' shelf life. Firstly, tomato fruits were harvested at the green mature stage and stored at 33℃ for 0, 10, 20, and 30 days, followed by a shift to 25℃. Subsequently, ten fruits were subjected to various treatments: A - control (25℃), B - 33℃ with 30-40% RH, C - 33℃ with 50-60% RH, and D - 33℃ with 80-90% RH. Different relative humidity (RH) levels were achieved using saturated salts, specifically MgCl2.6H2O, Mg (NO3)2.6H2O, and KCl+KNO3 for treatments B, C, and D, respectively. The evaluation encompassed parameters such as ethylene production, CO2 release, fruit firmness, weight loss, and color development. A higher temperature, such as 33℃, may be considered advantageous for the storage of green mature tomato fruit. Evidently, tomatoes were successfully stored for over 55 days at this temperature. Across all relative humidity (RH) conditions, there was more noticeable color development in fruits stored at 25°C compared to those stored at 33°C. Among the various RH conditions, fruits stored at 33°C with 80-90% RH experienced the least weight loss, although fruit firmness gradually declined over time. Storing green mature tomato fruit at 33°C with 30-40% RH resulted in the lowest ethylene production compared to 25°C and other RH conditions. Consequently, certain practical benefits of green mature tomato fruit under elevated temperatures and diverse relative humidity (RH) conditions are suggested. However, further detailed research may be necessary to explore potential metabolic changes.

Rapid testing in the food industry: the potential of Fourier transform near-infrared (FT-NIR) spectroscopy and spatially offset Raman spectroscopy (SORS) to detect raw material defects in hazelnuts (Corylus avellana L.)

The detection of raw material defects, e.g., due to incorrect or excessively long storage, is an important issue in incoming goods inspections in the food industry. Fast and easy-to-use analytical methods for evaluating the usability of raw materials are particularly important. In this study, the applicability of Fourier transform near-infrared (FT-NIR) spectroscopy and spatially offset Raman spectroscopy (SORS) for the detection of raw material defects was evaluated. For this purpose, six hazelnut batches stored at different temperatures, humidity levels, and storage times were used as examples in this pilot study. Classification models of samples before and after the different physical treatments show that the resulting changes can be detected by FT-NIR spectroscopy and SORS at elevated temperature and humidity. When one of the storage parameters is increased, FT-NIR spectroscopy is also useful for detecting differences between sample groups. In contrast, SORS cannot distinguish between pre- and post-stored samples when only one of the storage parameters is increased, making SORS unsuitable for incoming inspection of nuts. FT-NIR spectroscopy analysis is also a fast application, because freeze-drying of the sample material prior to analysis is not required as the results before and after freeze-drying are comparable. Combining the FT-NIR spectroscopy and SORS data in a low-level data fusion improved the classification models for samples stored at low storage temperatures, suggesting that the two methods provide complementary information. In summary, analyzing nuts with FT-NIR spectroscopy and SORS, as shown for hazelnuts, has the potential to identify abnormal samples during incoming goods inspections.

Mitigation of effects of heat and humidity at Tokyo 2020 Olympic Summer Games equestrian events

Abstract The physiological challenge of Tokyo 2020, the XXXII Olympic Summer Games held in July-August 2021, was adaptation to training and competing in the subtropical summer weather conditions. Dressage, Eventing, and Jumping horses (n = 248) arrived at 05:00-06:30 h on six European and two Australian overnight chartered flights 8-to-10 days prior to beginning competition. All horses were housed at Japan Racing Association Equestrian Park in Bagi Koen. Eventing Cross Country was held an hour’s drive away at Sea Forest. All stables and conveyances were air-conditioned. Cooling stations were available at both venues and consisted of tall arched tents with large containers of water chilled to ≤15 °C, cooling/misting fans, and rubberised flooring for traction safety. Training hours began at 06:00 h daily with a mandatory mid-day break between 11:00 and 15:00-16:00 h when arenas were re-opened until 22:00. Daytime temperatures ranged 28.8-36.8 °C and peak humidity remained high throughout the Games (58-97%). There were no heat-related illnesses in horses observed by clinic veterinarians who were present at all training and competition rings whenever horses were exercising. Individual horses received elective intravenous fluids (10 litre minimum) on arrival in Japan, after cross country, and/or before departure. Reported ailments included post-transport pneumonia, exercise-induced pulmonary haemorrhage, orthopaedic injury, laceration, impaction colic, acute piroplasmosis, and laminitis. A persistent brisk westerly wind began nightly around 17:00 h, making evening competition sessions cooler than daytime training sessions. It was concluded that safe competitions were held despite persistently elevated subtropical ambient heat and humidity conditions.