Intense Ultraviolet Radiation Research Articles

Potential for photosynthesis on Mars within snow and ice

On Earth, solar radiation can transmit down to multiple metres within ice, depending on its optical properties. Organisms within ice can harness energy from photosynthetically active radiation while being protected from damaging ultraviolet radiation. On Mars, the lack of an effective ozone shield allows ~30% more damaging ultraviolet radiation to reach the surface in comparison with Earth. However, our radiative transfer modelling shows that despite the intense surface ultraviolet radiation, there are radiatively habitable zones within exposed mid-latitude ice on Mars, at depths ranging from a few centimetres for ice with 0.01–0.1% dust, and up to a few metres within cleaner ice. Numerical models predict that dense dusty snow in the martian mid-latitudes can melt below the surface at present. Thus, if small amounts of liquid water are available at these depths, mid-latitude ice exposures could represent the most easily accessible locations to search for extant life on Mars.

A 10 km daily-level ultraviolet-radiation-predicting dataset based on machine learning models in China from 2005 to 2020

Abstract. Ultraviolet (UV) radiation is closely related to health; however, limited measurements have hindered further investigation of its health effects in China. Machine learning algorithms have been widely used to predict environmental factors with high accuracy, but a limited number of studies have implemented it for UV radiation. The main aim of this study is to develop a UV radiation prediction model using the random forest approach and predict the UV radiation with a daily and 10 km resolution in mainland China from 2005 to 2020. The model was developed with multiple predictors, such as UV radiation data from satellites as independent variables and ground UV radiation measurements from monitoring stations as the dependent variable. Missing satellite-based UV radiation data were obtained using the 3 d moving average method. The model performance was evaluated using multiple cross-validation (CV) methods. The overall R2 and root mean square error between measured and predicted UV radiation from model development and model 10-fold CV were 0.97 and 15.64 W m−2 and 0.83 and 37.44 W m−2 at the daily level, respectively. The model that incorporated erythemal daily dose (EDD) retrieved from the Ozone Monitoring Instrument (OMI) had a higher prediction accuracy than that without it. Based on predictions of UV radiation at the daily level, 10 km spatial resolution, and nearly 100 % spatiotemporal coverage, we found that UV radiation increased by 4.20 %, PM2.5 levels decreased by 48.51 %, and O3 levels increased by 22.70 % from 2013–2020, suggesting a potential correlation among these environmental factors. The uneven spatial distribution of UV radiation was associated with factors such as latitude, elevation, meteorological factors, and season. The eastern areas of China pose a higher risk due to both high population density and high UV radiation intensity. Using a machine learning algorithm, this study generated a gridded UV radiation dataset with extensive spatiotemporal coverage, which can be utilized for future health-related research. This dataset is freely available at https://doi.org/10.5281/zenodo.10884591 (Jiang et al., 2024).

Impact of Plastic Mulching on Soil Properties and Heavy Metal Dynamics in Agricultural Systems: A Case Study from Manikganj, Bangladesh

This research study examines the impact of different types and sizes of plastics on various soil properties. Clay loam soil samples were collected from Paril village, Manikganj district, Bangladesh, and subjected to plastic incubation experiments. The plastics underwent 180 days of intense ultraviolet (UV) radiation to simulate natural sunlight degradation. The soil samples were mixed with three types of plastics (P1, P2, P3) and two sizes (1mm, 10mm) in individual pots, with and without the addition of zinc sulfate. The soil properties, including pH, total dissolved solids (TDS), available zinc, cation exchange capacity (CEC), nitrogen content, and total phosphorus, were analyzed using various techniques. The results indicate significant variations in pH and TDS values influenced by plastic size and type. The available zinc content differed among plastic types, and plastic size affected CEC values. Nitrogen content was influenced by plastic size, with smaller particles having a greater impact. Total phosphorus content varied with different plastic types. These findings contribute to our understanding of the potential effects of plastics on soil properties and highlight the need for further investigation into the underlying mechanisms.

Unique Features of Extremely Halophilic Microbiota Inhabiting Solar Saltworks Fields of Vietnam.

The artificial solar saltworks fields of Hon Khoi are important industrial and biodiversity resources in southern Vietnam. Most hypersaline environments in this area are characterized by saturated salinity, nearly neutral pH, intense ultraviolet radiation, elevated temperatures and fast desiccation processes. However, the extremely halophilic prokaryotic communities associated with these stressful environments remain uninvestigated. To fill this gap, a metabarcoding approach was conducted to characterize these communities by comparing them with solar salterns in northern Vietnam as well as with the Italian salterns of Motya and Trapani. Sequencing analyses revealed that the multiple reuses of crystallization ponds apparently create significant perturbations and structural instability in prokaryotic consortia. However, some interesting features were noticed when we examined the diversity of ultra-small prokaryotes belonging to Patescibacteria and DPANN Archaea. Surprisingly, we found at least five deeply branched clades, two from Patescibacteria and three from DPANN Archaea, which seem to be quite specific to the Hon Khoi saltworks field ecosystem and can be considered as a part of biogeographical connotation. Further studies are needed to characterize these uncultivated taxa, to isolate and cultivate them, which will allow us to elucidate their ecological role in these hypersaline habitats and to explore their biotechnological and biomedical potential.

Nuclear Magnetic Resonance (NMR) Assessment of Bio and Crude Oil-Based Rejuvenation

Asphalt binders in pavements lose their stability through aging and eventually fail in the field. Using nuclear magnetic resonance (NMR) to monitor the primary longitudinal relaxation time of asphalt samples and the ratio of material that carries this primary relaxation time has been shown to indicate the impact of ultraviolet (UV) radiation on the aging of asphalt pavements. Longitudinal NMR relaxation was used to investigate two types of proposed asphalt rejuvenators, a bio-oil-based rejuvenator and a crude-oil-based rejuvenator. Two different binders with the performance grades (PG) 64-22 and 76-22 were considered for their interactions with the rejuvenators. After 72 h of exposure to intense UV radiation, specifically designed NMR relaxometry experiments were applied to compare the rejuvenation capabilities of the two rejuvenator samples. The crude oil-based rejuvenator was found to exhibit relaxation times similar to the binder samples while the bio-based material showed relaxation times that pointed to different nuclear hydrogen environments. Both rejuvenators reduced the primary relaxation time of the PG 76-22 binder, which indicates that their stiffness was reduced. Both types of rejuvenators also seemed to prevent the effects of UV aging. Two mechanisms of rejuvenation were identified by NMR relaxometry. The primary relaxation time can be used to indicate a change in stiffness while the primary ratio of the material is tied to oxidative aging. Oxidative aging creates distinct hydrogen environments due to asphaltene aggregation. The bio-based rejuvenator only reduced the binder’s stiffness, while the crude oil-based rejuvenator also reduced the aggregation of asphaltenes. Consequently, the bio-based rejuvenator could be classified as an asphalt softener, while the oil-based material acted like a true rejuvenator.

An HD-Zip III transcription factor, BjPHVa, negatively regulates non-glandular trichome formation in Brassica juncea.

Trichomes are specialized structures derived from epidermal cells. Non-glandular trichomes primarily protect plants from herbivores and intense ultraviolet radiation by acting as a physical barrier. Recent research has highlighted the importance of homeodomain leucine zipper (HD-Zip) IV transcription factors (TFs) in promoting trichome development. In this study, an HD-Zip III TF called PHAVOLUTA (BjPHVa) was identified as a negative regulator of non-glandular trichome initiation in Brassica juncea. Genome editing of BjPHVa resulted in a significant increase in trichome number in B. juncea. Co-expression networks revealed a strong association between trichome development and the HD-Zip family, which was supported by transcriptomic analysis findings. An R2R3-MYB TF, BjGL1a, a key regulator of trichome development, was found to be associated with BjPHVa-regulated trichome development. Knockdown of BjGL1a expression resulted in reduced trichome number in B. juncea. BjPHVa was observed to interact directly with BjGL1a while binding to the BjGL1a promoter, resulting in the inhibition of BjGL1a transcription. These results provide new insights into the identification of regulators involved in trichome development and offer new opportunities to enhance resistance to predicted stresses through genome editing targeting PHVa within Brassicaceae.

Characteristics of water dissolved organic matter in Zoige alpine wetlands, China

BackgroundDissolved organic matter (DOM) plays a significant role in the biogeochemical cycle of crucial elements in aquatic ecosystem. However, it is still not clear on the spectral characteristics of water DOM in different types of alpine wetlands, which have less anthropogenic influences and intensive ultraviolet radiation. Here, we collected 107 water samples from marsh, lake, and river wetlands in the Zoige plateau, China, and analyzed the chemical characteristics, compositions, and potential sources of chromophoric DOM by combining UV–vis spectroscopy and excitation–emission matrix fluorescence spectroscopy coupled with parallel factor analysis (EEMs-PARAFAC).ResultsUVC and UVA fulvic-like substances were the prevailing fluorescence components in water DOM, which accounted for 23.74–71.59% and 16.76–30.01% of the total fluorescence intensity, respectively. Compared with the lake and river wetlands, fluoresce intensities of UVC and UVA fulvic-like substances in DOM were higher in marsh wetland. Marsh wetlands possessed the highest SUVA254, E2/E3, E2/E4, and E4/E6 of DOM, suggesting higher humification degree, higher relative molecular nominal size, and higher aromaticity. And the E2/E4 ratios in most water samples were higher than 12, indicating water DOM was mainly derived from autochthonous sources in alpine wetlands.ConclusionsWetland types strongly affected the spectral characteristics of water DOM in Zoige plateau. These findings may be beneficial for sustainable management of alpine wetlands.Graphical

Analysis of data on phytophotodermatitis caused by contact with the sap of plants of the genus Hogweed (<i>Heracleum</i> L.)

The rapid spread of overgrowth of plants of the genus Hogweed, associated with their use as an agricultural fodder crop, is currently a serious problem for the Russian Federation. This process has a negative impact on the biodiversity of the vegetation cover, destroying natural ecosystems and causing significant economic damage. However, the active spread of hogweeds on the territory of the Russian Federation would not be so catastrophic if it were not for their aggressive properties: in contact with the skin, plant sap causes phytophotodermitis, which is a burn similar to thermal burns of I, II and III degrees. The article considers qualitative and quantitative composition of the main biologically active substances of hogweeds sap and shows that the biologically active substances causing phytophotodermatitis are furanocoumarins. It has been established that the pronounced photosensitizing activity of furanocoumarins is determined by the presence of a furan ring at positions 6,7 and 7,8 of coumarin. Such compounds include psoralen and its main derivatives: xanthotoxin, bergapten, bergamotin, imperatorin, isopimpinellin and angelicin (isopsoralen) and its main derivatives: sfondin, pimpinellin, isobergapten. Substitution of furan ring condensed with coumarin ring as well as change of its position leads to loss of photosensitizing activity. It was determined that the activity of plant sap of the genus Hogweed is in direct dependence on such factors as qualitative and quantitative content of furanocoumarins in the plant sap, the amount of sap and the area of the skin lesion zone, the time of contact of the affected skin areas with the plant sap, the intensity of ultraviolet irradiation and the time of its effect on the affected areas, as well as the peculiarities of each person (e.g., age, skin phototype). The methods of standard therapy of three clinical forms of phytophotodermatitis were analyzed. It was found that currently no specific clinical recommendations for the diagnostics and treatment of phytophotodermatitis resulting from contact with the sap of hogweeds. At the end of the article, the conclusion is formulated that one of current and promising tasks of pharmaceutical technology may be the development of drugs used in the treatment of burns caused by the sap of plants of the genus Hogweed, taking into account the mechanism of action of furanocoumarins.

Nitrogen-Doped Carbon Quantum Dots with Photoactivation Properties for Ultraviolet Ray Detection.

Photoactivation is a phenomenon that could enhance the photoluminescence (PL) and photostability upon UV/vis light exposure, which is usually observed in CdSe/ZnS quantum dots (QDs). However, the photoactivation phenomenon has been scarcely reported in fluorescent carbon quantum dots (CQDs). Herein, the nitrogen-doped carbon quantum dots (N-CQDs) were prepared through a facile solvothermal approach with naphthalenetracarboxylic dianhydride and serine as precursors. Upon simple UV light irradiation for 10 min, the fluorescence quantum yield (QY) of N-CQDs could increase up to 10-fold. Based on this phenomenon, the N-CQDs were explored as an ultraviolet (UV) light sensor to assess the intensity of ultraviolet radiation in sunlight and indirectly evaluate the UV-blocking efficiency of various sunscreen products. Thus, this contribution not only provided an insight into developing a low-cost UV detector but also opened a door for the development of carbon quantum dots with converse-photobleaching properties.

Impact of surface ultraviolet radiation intensity on hospital admissions for ischemic and hemorrhagic stroke: A large-scale database study using distributed lag nonlinear analysis, 2015-2022, in Harbin, China

ObjectivesOur aim is to evaluate the impact of surface ultraviolet radiation intensity on hospital admissions for stroke and to compare the correlation and differences among different subtypes of strokes. Materials and methodsWe collected daily data on surface ultraviolet radiation intensity, temperature, air pollution, and hospital admissions for stroke in Harbin from 2015 to 2022. Using a distributed lag non-linear model, we determined the correlation between daily surface ultraviolet radiation intensity and the stroke admission rate. Relative risks (RR) with 95% confidence intervals (CI) and attributable fractions (AF) with 95% CI were calculated based on stroke subtypes, gender, and age groups. ResultsA total of 132,952 hospitalized stroke cases (including hemorrhagic and ischemic strokes) were included in the study. We assessed the non-linear effects of ultraviolet intensity on hospitalized patients with ischemic and hemorrhagic strokes. Compared to the maximum morbidity benchmark ultraviolet intensity (19.2 × 10^5 for ischemic stroke and 20.25 for hemorrhagic stroke), over the 0-10 day lag period, the RR for extreme low radiation (1st percentile) was 0.86 (95% CI: 0.77, 0.96), and the RR for extreme high radiation (99th percentile) was 0.86 (95% CI: 0.77, 0.96). In summary, -4.842% (95% CI: -7.721%, -2.167%) and -1.668% (95% CI: -3.061%, -0.33%) of ischemic strokes were attributed to extreme low radiation intensity with a lag of 0 to 10 days and extreme high radiation intensity with a lag of 0 to 5 days, respectively. The reduction in stroke hospitalization rates due to low or high ultraviolet intensity was more pronounced in females and younger individuals compared to males and older individuals. None of the mentioned ultraviolet intensity intensities and lag days had a statistically significant impact on hemorrhagic stroke. ConclusionsOur study fundamentally suggests that both lower and higher levels of surface ultraviolet radiation intensity in Harbin, China, contribute to a reduced incidence of ischemic stroke, with this effect lasting approximately 10 days. This finding holds significant potential for public health and clinical relevance.

P-726 Age of natural menopause and its associated factors among ethnic Han and Tibetan Chinese women: findings from a China Multi-Ethnic Cohort (CMEC) study

Abstract Study question Is there a disparity in the age of natural menopause (ANM) between ethnic Han and Tibetan Chinese women? Summary answer The present study has discovered a significant difference in the ANM between ethnic Han and Tibetan Chinese women. What is known already The ANM indicates the termination of ovarian function and the reproductive lifespan of the ovary. Factors influencing ANM include genetic, ovarian diseases or surgery, environment, and unhealthy lifestyles. Some studies reported that ANM was different among different ethnics, such as lower in African, Latin American, Asian, whereas higher in Europe, Australia and America. Ethnic Tibetan Chinese mainly resides in an environment with high altitude, low oxygen level, and intense ultraviolet radiation. They also have unique dietary and lifestyle habits, which might result in different ANM compared to ethnic Han Chinese. However, there are few studies on ANM between the two. Study design, size, duration We performed a cross-section study involving 11174 ethnic Han and 1049 ethnic Tibetan Chinese postmenopausal women from Chengdu city and Aba Prefecture in Sichuan province. The participants were recruited by the China Multi-Ethnic Cohort (CMEC) study from May 2018 to September 2019. Participants/materials, setting, methods Information of the postmenopausal women was derived from CMEC baseline questionnaire. Ethnicity was used as the primary exposure variable. Regression models incorporating linear, quadratic and quadratic with interaction terms on age were used to assess the association of ANM with the ethnicity. Main results and the role of chance The mean ANM of ethnic Han Chinese women was later than that of ethnic Tibetan Chinese women (48.50 ± 4.20 years vs. 47.80 ± 4.92 years, P < 0.05). Multivariate linear regression analysis showed a significant disparity in the ANM between the two groups, and sexual life, higher education, no smoking, never experienced severe food shortage, later age of menarche and more times of pregnancy were associated with later ANM (P < 0.05). Furthermore, the quadratic and interaction models demonstrated a significant non-linear association between the ANM and the age at the time of survey. In both groups, the ANM showed a trend of first rising and then declining with the increase of the age at the time of survey Notably, among women younger than 68, the ANM of ethnic Han Chinese was significantly later than that of ethnic Tibetan Chinese. Limitations, reasons for caution The information regarding menopausal women, including ANM and potential influencing factors were obtained from self-reports. Additionally, the duration of exposure to these potential influencing factors remained uncertain. Wider implications of the findings This is the first study with a large sample size comparing ANM between ethnic Han and Tibetan Chinese women. Notably, the age at the time of survey and ethnicity have independently contributed to variation in ANM, and significant interaction effects on ANM are found between age of survey and ethnicity. Trial registration number not applicable

AGE, SEX, AND TYPES OF OCCUPATION WITH HISTOPATHOLOGICAL TYPES IN PATIENTS WITH OCULAR SURFACE SQUAMOUS NEOPLASIA (OSSN) IN A TERTIARY HOSPITAL IN SURABAYA, INDONESIA

Highlights The histopathological types of OSSN were significantly associated with age and occupation. The study's findings enhance the understanding of OSSN in Indonesia and emphasize the importance of UV exposure, occupation, and age in its development. Abstract Background: Ocular Surface Squamous Neoplasia (OSSN) is a spectrum of tumors affecting the conjunctiva and cornea, in which a more invasive type of OSSN has a higher recurrence rate. As a tropical country, Indonesia is constantly exposed to intense ultraviolet (UV) radiation, the main risk factor for OSSN. Despite this, there are very few studies regarding OSSN in Indonesia. Objective: This study aimed to analyze the association between sociodemographic characteristics such as age, sex, and types of occupation (outdoor and indoor) and histopathological types of OSSN to fill the gap in research and contribute to early diagnostic strategies. Material and Method: Sociodemographic and histopathological data were extracted from the medical records of patients who were histopathologically diagnosed with OSSN at Dr. Soetomo General Hospital from 2017 to 2021. Data from 88 samples that met the inclusion and exclusion criteria were classified and analyzed with descriptive statistics and a two-sided Fisher's exact test using SPSS version 27.0 (IBM Corp., Armonk, N.Y., USA). Result: The exact test results of the two-sided fisher revealed a statistically significant relationship between age (p = 0.0004) and occupation type (p = 0.049) with histopathological types of OSSN. However, no significant association was found between sex and histopathological types of OSSN (p = 0.130). Conclusion: Age and occupation were found to have a significant association with the histopathological types of OSSN, reinforcing the need for further exploration of its strength and nature to be considered by future researchers.

Coupled effects of UV radiation and freeze–thaw cycles on the fracture behavior of asphalt concrete

The Qinghai-Tibet Plateau in China is characterized by extreme climate conditions, including intense ultraviolet (UV) radiation, frequent freeze–thaw cycles (FTCs), and significant temperature fluctuations. These conditions contribute to severe cracking in asphalt pavements. This study aims to investigate the impact of coupled damage from UV radiation and FTCs on the fracture behavior of asphalt concrete. To simulate the coupled environmental damage (CED) experienced by asphalt pavement in the field, an alternating two-factor laboratory procedure was developed. This procedure reflects the climatic conditions of the Qinghai-Tibet Plateau. The semi-circular bending test, combined with digital image correlation technology, was employed to evaluate the effects of temperature and CED cycles on fracture-related parameters of asphalt concrete. These parameters include the load–displacement curve, fracture toughness, and fracture energy. Fracture behavioral characteristics such as horizontal strain, crack length, crack propagation path, and crack mouth opening displacement were also analyzed. The results indicate that coupled damage from UV radiation and FTCs significantly weakened the fracture resistance of asphalt concrete. Compared with other fracture-related indicators, the most significant reduction observed was the fracture energy of 68.1%. The two environmental factors exhibited a mutually reinforcing effect on the fracture properties of asphalt concrete, with low temperatures further intensifying their influence. CED cycles delayed the initiation of cracks in asphalt concrete but accelerated crack propagation. This led to a reduction in time to failure by up to 57.6% and a maximum reduction in horizontal strain of 24%. Additionally, the cracking propagation path of asphalt concrete became more linear with increased crack mouth opening displacement. Future research should focus on the evolution of damage accumulation in asphalt concrete under CED cycles, with the goal of establishing predictive models for long-term service life.

UV radiation-induced peptides in frog skin confer protection against cutaneous photodamage through suppressing MAPK signaling.

Overexposure to ultraviolet light (UV) has become a major dermatological problem since the intensity of ultraviolet radiation is increasing. As an adaption to outside environments, amphibians gained an excellent peptide-based defense system in their naked skin from secular evolution. Here, we first determined the adaptation and resistance of the dark-spotted frogs (Pelophylax nigromaculatus) to constant ultraviolet B (UVB) exposure. Subsequently, peptidomics of frog skin identified a series of novel peptides in response to UVB. These UV-induced frog skin peptides (UIFSPs) conferred significant protection against UVB-induced death and senescence in skin cells. Moreover, the protective effects of UIFSPs were boosted by coupling with the transcription trans-activating (TAT) protein transduction domain. In vivo, TAT-conjugated UIFSPs mitigated skin photodamage and accelerated wound healing. Transcriptomic profiling revealed that multiple pathways were modulated by TAT-conjugated UIFSPs, including small GTPase/Ras signaling and MAPK signaling. Importantly, pharmacological activation of MAPK kinases counteracted UIFSP-induced decrease in cell death after UVB exposure. Taken together, our findings provide evidence for the potential preventive and therapeutic significance of UIFSPs in UV-induced skin damage by antagonizing MAPK signaling pathways. In addition, these results suggest a practicable alternative in which potential therapeutic agents can be mined from organisms with a fascinating ability to adapt.

Laboratory-accelerated simulation and calibration method for ultraviolet aging of asphalt binders based on radiation equivalent conversion

Ultraviolet (UV) radiation is a significant environmental factor that accelerates the aging of asphalt pavements. To address the gap in the equivalence conversion relationship between laboratory simulation parameters and field environmental factors for asphalt pavement aging in the Tibet area of China, this study investigates the relationship between laboratory simulations and field service for asphalt aging. The results indicate that using macroscopic rheological parameters (rutting factor (G*/sin δ), average recovery rate (R), and average non-recoverable creep compliance (Jnr)) and microscopic parameters (sulfoxide index (SI) and glass transition temperature (Tg)) as quantitative indicators can evaluate the equivalent degrees of laboratory and field aging. Furthermore, this study introduces a correction coefficient for laboratory-accelerated simulated aging to improve the accuracy of the equivalent radiation conversion formula. The correction coefficient range for 90# matrix asphalt is 1.36–2.05, while the range for SBS modified asphalt is 0.82–1.64. This study provides a valuable database for establishing the relationship between laboratory simulations and field service for asphalt aging and offers a parameter basis and technical support for designing durable asphalt pavements in areas with intense UV radiation.

PRESOLRE: study protocol for a primary school-based, cluster randomised controlled trial of three sun exposure risk prevention strategies on Reunion Island

IntroductionReunion Island, a French overseas department, is located in the southern hemisphere, close to the Capricorn tropic. This island has a multicultural and multiethnic population of 860 000 inhabitants, a...

Facile fabrication of multifunctional aramid fibers for excellent UV resistance in extreme environments

Aramid fibers (AFs) are widely applied as structural material, cordage, and versatile protection in many harsh environments, including space and deep sea. However, intense ultraviolet (UV)/ irradiation, high/low temperatures, and/or chemical solvent with strong acid/alkali/corrosion feature seriously affect their mechanical properties, thus severely shorten the life cycle of AF-based products. Inspiration by the principle of multiple refractions and partly reflections, an innovative strategy by depositing of laminated Al2O3/TiO2 composite onto the surface of poly(m-phenylene isophthalamide) (PMIA) via atomic layer deposition (ALD) technique was presented. The tenacity of ALD-coated PMIA only decreases by ∼ 8 %, and the yellowness index (YI) only increasing to 129.24 %, far lower than 321.63 % of pristine PMIA fabric under the combination of intense UV irradiation (4260 W/m2) and high temperature (200 °C + ) for 6 h, which equals to continuous strong sunlight exposure for approximately 7.5 years. Meanwhile, ultraviolet protection factor (UPF) value increased to 126.4, which is double that of the pristine PMIA fabric, exhibiting an impressive UV-resistance property. Furthermore, the ALD-coated PMIAs also shows a significant enhancement in both chemical and thermal stabilities. In all, this work not only forge a new route for the functionalization of fibrous materials, but also exhibits great promise for next generation advanced composite material and cutting-edge equipment in harsh environment.

Metagenomic profiling of halites from the Atacama Desert: an extreme environment with natural perchlorate does not promote high diversity of perchlorate reducing microorganisms.

We surveyed the presence of perchlorate-reducing microorganisms in available metagenomic data of halite environments from the Atacama Desert, an extreme environment characterized by high perchlorate concentrations, intense ultraviolet radiation, saline and oxidizing soils, and severe desiccation. While the presence of perchlorate might suggest a broad community of perchlorate reducers or a high abundance of a dominant taxa, our search reveals a scarce presence. In fact, we identified only one halophilic species, Salinibacter sp003022435, carrying the pcrA and pcrC genes, represented in low abundance. Moreover, we also discovered some napA genes and organisms carrying the nitrate reductase nasB gene, which hints at the possibility of cryptic perchlorate reduction occurring in these ecosystems. Our findings contribute with the knowledge of perchlorate reduction metabolism potentially occurring in halites from Atacama Desert and point towards promising future research into the perchlorate-reducing mechanism in Salinibacter, a common halophilic bacterium found in hypersaline ecosystems, whose metabolic potential remains largely unknown.

Natural weathering effects of nonwoven geotextile exposed to different climate conditions

Humidity, air temperature, rainfall and solar radiation all contribute to the weathering of geosynthetics. Over time, the useful life can be affected and changes in properties can be observed, which affects the performance of these materials. As geosynthetics durability analyses must encompass each work condition, assessing the climate effects is essential for design purposes. This study exposed a nonwoven needle-punched poly(ethylene) terephthalate geotextile to natural weathering in three Brazilian cities (different exogenous environments) for 18 months. Mechanical tests were conducted to evaluate the geotextile changes due to weathering. This was demonstrated by the results: exposure to weather leads to the deterioration of the geotextile mechanical properties and increased stiffness. After four months, the tensile strength fell by half, while the deformation needed more than twelve months to have this same reduction; ultraviolet radiation intensity was the most effective weathering condition in the field; humidity and rainfall can affect the stiffness of geotextiles; the impact of accumulated climate factors gradually showed a convergence in the response of geotextile to weathering. Thus, this work highlights the need to evaluate the climate conditions in each location to understand the material's behavior on the exposure time.

Comparative skin histological and transcriptomic analysis of Rana kukunoris with two different skin colors

This study compares the skin structures of Rana kukunoris with two different skin colors living in the same area of Haibei in the Northeastern Qinghai-Tibet Plateau. The skin thickness of the khaki R. kukunoris was significantly greater than that of the brown R. kukunoris (P < 0.01), and significantly more mucous and granular glands were present on the dorsal skin of the khaki frog (P < 0.05). Meanwhile, the melanocytes on the dorsal skin of the brown frog were significantly larger than those on the khaki one (P < 0.05). Morphological changes in the expansion and aggregation of melanocytes seemed to deepen the skin color of R. kukunoris. Moreover, transcriptome sequencing identified tyrosine metabolism, melanogenesis, and riboflavin metabolism as the main pathways involved in melanin formation and metabolism in brown R. kukunoris. TYR, MC1R was upregulated as the skin color of R. kukunoris was deepened and contributed to melanin production and metabolism. In contrast, the khaki frog had significantly more upregulated genes and metabolic pathways related to autoimmunity. The khaki frog appeared to defend against ultraviolet (UV) radiation-induced damage by secreting mucus and small molecular peptides, whereas the brown frog protected itself by distributing a large amount of melanin. Hence, the different skin colors of R. kukunoris might represent different adaptation strategies for survival in the intense UV radiation environment of the Qinghai-Tibet Plateau.