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1.
BMC Pregnancy Childbirth ; 24(1): 454, 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38951765

RÉSUMÉ

OBJECTIVE: The Moon has a noticeable influence on the Earth due to its gravity, the most visible manifestation of which are tides. We aimed to see if the Moon's daily cycle, like the Sun's, affects the prevalence and incidence of childbirth. METHODS: In this retrospective cohort study, we examined all deliveries at the Academic Hospital of Udine between 2001 and 2019. All consecutive singleton pregnancies with spontaneous labor and vaginal delivery were included. RESULTS: During the period, 13,349 singleton pregnancies with spontaneous labor and vaginal delivery were delivered in 6939 days. A significantly higher prevalence of deliveries was found with the Moon above the horizon (50.63% vs. 49.37%, p < 0.05). Moreover, during the day, there was a significantly higher prevalence of deliveries than during nighttime (53.74% vs. 45.79%, p < 0.05). Combining the Moon and Sun altitude, the majority of deliveries were registered when both were above the horizon (27.39% vs. 26.13%, 23.25%, or 23.24%, p < 0.05). These findings were confirmed in multivariate analysis after adjusting for parity, gestational age, or season. We found no correlation between birth and the Moon phase. CONCLUSIONS: Our data support the interaction of the Moon and the Sun in determining the time of birth. More research is needed to understand these phenomena and improve our understanding of labor initiation mechanisms.


Sujet(s)
Taux de natalité , Lune , Humains , Femelle , Études rétrospectives , Grossesse , Adulte , Taux de natalité/tendances , Lumière du soleil , Accouchement (procédure)/statistiques et données numériques , Accouchement (procédure)/méthodes , Parturition
2.
J Drugs Dermatol ; 23(7): 571-574, 2024 07 01.
Article de Anglais | MEDLINE | ID: mdl-38954614

RÉSUMÉ

Despite the widespread interest in dermatology on TikTok, studies have shown most related videos are not produced by board-certified dermatologists (BCDs) or other health professionals. To see if this trend extended to sun protection, we examined TikTok videos associated with sun safety to determine the proportion produced by BCDs. From August 25, 2023, to August 27, 2023, investigators input the following hashtags into the TikTok search bar: #sunscreen, #sunprotection, #spf, #skincancer, and #skinprotection. The top 100 videos in each category were analyzed and categorized based on the content creator. Additionally, we assessed whether videos explicitly addressed skin of color (SOC). Of the analyzed videos, only 16.6% originated from BCDs. Beauty bloggers/bloggers were the most prevalent creators in this category (38.7%), followed by patients/consumers (33.7%). Only 2.8% of the videos pertained to SOC patients. This highlights a gap in the type of educational content generated by dermatologists on TikTok, with sun safety being a potential subject to target within social media. Additionally, the small representation of videos addressing SOC patients underscores the need for more diverse and inclusive educational skincare content on TikTok.J Drugs Dermatol. 2024;23(7):571-574. doi:10.36849/JDD.8179.


Sujet(s)
Médias sociaux , Produits antisolaires , Humains , Études transversales , Produits antisolaires/administration et posologie , Médias sociaux/statistiques et données numériques , Coup de soleil/prévention et contrôle , Dermatologie , Enregistrement sur magnétoscope , Lumière du soleil/effets indésirables , Pigmentation de la peau/effets des radiations , Dermatologues/statistiques et données numériques , Tumeurs cutanées/prévention et contrôle , Éducation du patient comme sujet/méthodes
3.
Nutrients ; 16(13)2024 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-38999763

RÉSUMÉ

Vitamin D3 deficiency and insufficiency are becoming a common global issue for us, especially in the most industrially developed countries. The only acknowledged activity of vitamin D3 in vertebrates is to promote the absorption of calcium and, therefore, allow for the mineralization of bones. Accordingly, its deficiency is associated with diseases such as rickets. Other numerous vital functions associated with vitamin D3 are yet to be considered, and the function of vitamin D2 in plants is unknown. Thus, 100 years after its discovery, the importance of vitamin D still seems to be unacknowledged (except for rickets), with little attention given to its decrease throughout the world. In this review, I suggest that vitamin D deficiency and insufficiency may be linked to the westernized lifestyle in more developed countries. Furthermore, I suggest that, rather than the calcemic activity, the main function of vitamin D is, in general, that of strengthening living organisms. I conclude with the hypothesis that vitamin D deficiency may represent a marker for a greater risk of chronic inflammatory diseases and a shorter life expectancy.


Sujet(s)
Carence en vitamine D , Vitamine D , Carence en vitamine D/épidémiologie , Humains , Vitamine D/sang , Lumière du soleil , Rachitisme/étiologie , Rachitisme/épidémiologie , Rachitisme/prévention et contrôle , Mode de vie , Santé mondiale
4.
Nutrients ; 16(13)2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38999866

RÉSUMÉ

The purpose of this study was to evaluate the vitamin D status and determine the factors influencing it in the Drâa-Tafilalet community (southeastern Morocco). Sociodemographic factors, health, cognitive status, sun exposure, and nutritional conditions were examined to help us understand their association with vitamin D status. Vitamin D data were gathered through laboratory testing, while demographic and health information was collected through interviews with participants in 2023. The study involved 100 participants aged 60 and above, most of whom were women (85%) rather than men (15%). The majority of participants were Arabs (90%), with a minority being Amazigh (10%). The average vitamin D level was 31.83 ± 10.55 ng/mL, varying based on participants' age, education, and gender. Sun-exposed individuals exhibited significantly higher mean vitamin D levels (33.56 ± 11.99 ng/mL) compared to those with limited sun exposure (28.97 ± 9.28 ng/mL). Moreover, the time spent outdoors, seasonal changes, and the duration of sun exposure affected the levels of vitamin D. These findings depict the vitamin D status of the elderly population of Drâa-Tafilalet, recognized as one of Morocco's poorest regions, shedding light on the significant influencers. Nonetheless, additional research is necessary to explore the correlation between dietary habits, sunlight exposure, and vitamin D levels in both young and elderly populations.


Sujet(s)
État nutritionnel , Carence en vitamine D , Vitamine D , Humains , Maroc , Mâle , Femelle , Adulte d'âge moyen , Vitamine D/sang , Sujet âgé , Carence en vitamine D/épidémiologie , Carence en vitamine D/sang , Lumière du soleil , Facteurs sociodémographiques , Facteurs socioéconomiques , État de santé , Sujet âgé de 80 ans ou plus
6.
Cutis ; 113(5): E15-E21, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-39042130

RÉSUMÉ

Understanding the genetic adaptations that occurred as humans migrated out of Africa to higher latitudes helps explain on a population-wide level how UV radiation (UVR) exposure will have varying consequences and benefits in patients of different skin pigmentations. It has been hypothesized that the need for efficient vitamin D synthesis was the primary driver for the skin-lightening process that evolutionarily occurred as humans migrated to higher latitudes. This review analyzes the level of support for the hypothesis that skin lightening occurred to enable adequate vitamin D synthesis in populations that migrated to areas with less UVR. Our literature search supported the hypothesis that through natural selection and intricate genetic adaptations, humans who migrated to areas with lower levels of UVR underwent a skin-lightening process to avoid the consequences of vitamin D deficiency. Our review includes an analysis of migration patterns out of Africa and how these affected pigmentation genes that are found in certain ethnic populations can be used to better understand this critical adaptation process when counseling patients on the need for sun protection.


Sujet(s)
Adaptation physiologique , Pigmentation de la peau , Rayons ultraviolets , Vitamine D , Humains , Migration humaine , Sélection génétique , Lumière du soleil/effets indésirables , Rayons ultraviolets/effets indésirables , Vitamine D/métabolisme , Carence en vitamine D
7.
Am J Bot ; 111(7): e16371, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39001583

RÉSUMÉ

PREMISE: Light is essential for plants, and local populations exhibit adaptive photosynthetic traits depending on their habitats. Although plastic responses in morphological and/or physiological characteristics to different light intensities are well known, adaptive divergence with genetic variation remains to be explored. This study focused on Saxifraga fortunei (Saxifragaceae) growing in sun-exposed and shaded habitats. METHODS: We measured the leaf anatomical structure and photosynthetic rate of plants grown in their natural habitats and in a common greenhouse (high- and low-intensity light experimental sites). To assess differences in ecophysiological tolerance to high-intensity light between the sun and shade types, we evaluated the level of photoinhibition of photosystem II and the leaf mortality rate under high-intensity light conditions. In addition, population genetic analysis was conducted to investigate phylogenetic origins. RESULTS: Clear phenotypic differences were found between the sun and shade types despite their recent phylogenetic origin. The leaf anatomical structure and photosynthetic rate showed plastic changes in response to growing conditions. Moreover, the sun type had a well-developed palisade parenchyma and a higher photosynthetic rate, which were genetically fixed, and a lower level of photoinhibition under high-intensity light. CONCLUSIONS: Our findings demonstrate that light intensity is a selective pressure that can rapidly promote phenotypic divergence between the sun and shade types. While phenotypic changes in multiple photosynthetic traits were plastic, genetic divergence in specific traits related to adaptation to high-intensity light would be fundamental for ecotypic divergence to different light regimes.


Sujet(s)
Adaptation physiologique , Photosynthèse , Feuilles de plante , Saxifragaceae , Lumière du soleil , Feuilles de plante/anatomie et histologie , Feuilles de plante/physiologie , Feuilles de plante/effets des radiations , Feuilles de plante/génétique , Saxifragaceae/génétique , Saxifragaceae/physiologie , Saxifragaceae/anatomie et histologie , Lumière , Phylogenèse , Phénotype , Variation génétique , Écosystème , Complexe protéique du photosystème II/génétique
8.
J Environ Sci Health B ; 59(8): 540-549, 2024.
Article de Anglais | MEDLINE | ID: mdl-39034761

RÉSUMÉ

The variation in light within the environment triggers morphophysiological changes in plants and can lead to distinct responses in sun-exposed or shaded plants to glyphosate. The response of Urochloa genotypes subjected to desiccation with 2160, 1622.4, 1080, 524.4, 273.6, and 0.0 g ha-1 of glyphosate was evaluated in full sun and shade conditions. Cayana grass, mulato II grass, and sabiá grass - hybrids recently launched on the market, in addition to palisade grass and congo grass were evaluated. Under full sun, we achieved control of congo grass using 1080 g ha-1 of glyphosate, while the other grasses required 2160 g ha-1. In the low-light environment, sabiá grass was effectively controlled with 524.4 g ha-1 of glyphosate, but the other grasses needed 273.6 g ha-1. In shading, compared to full sun, the savings with glyphosate were 75 and 76% for the control of congo grass and sabiá grass, respectively, and 87% for palisade grass, mulato II grass and cayana grass. Increasing glyphosate doses leads to a decline in the quantum efficiency of photosystem II and in the electron transport rate, especially in the shade. Urochloa genotypes are more sensitive to glyphosate in the shade, which must be considered when determining the herbicide dose.


Sujet(s)
Glycine , , Herbicides , Poaceae , Glycine/analogues et dérivés , Glycine/pharmacologie , Herbicides/pharmacologie , Poaceae/effets des médicaments et des substances chimiques , Poaceae/effets des radiations , Poaceae/génétique , Poaceae/métabolisme , Lumière , Lumière du soleil
9.
Chemosphere ; 361: 142534, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38849097

RÉSUMÉ

This study aims the characterization of several tianeptine transformation products in ultrapure water by simulated sunlight irradiation. Tianeptine was completely degraded after 106 h of exposition following pseudo-first-order kinetics (half-life time = 12.0 ± 2.4 h). Furthermore, an ultra-high-performance liquid chromatography coupled with a high-resolution quadrupole time-of-flight-mass spectrometry method was developed and fully validated taking into account different method performance parameters for the quantification of tianeptine in river water up to a concentration of 400 pg L-1. Following a non-targeted approach based on mass data-independent acquisition, eight different transformation products not previously reported in the literature were identified and accordingly elucidated, proposing a photodegradation mechanism based on the accurate tandem mass spectrometry information acquired. Irradiation experiments were replicated for a tianeptine solution prepared in a blank river water sample, resulting in the formation of the same transformation products and similar degradation kinetics. In addition, a toxicity assessment of the photoproducts was performed by in silico method, being generally all TPs of comparable toxicity to the precursor except for TP1, and showing a similar persistence in the environment except for TP2 and TP6, while TP4 was the only TP predicted as mutagenic. The developed method was applied for the analysis of four river water samples.


Sujet(s)
Photolyse , Spectrométrie de masse en tandem , Thiazépines , Polluants chimiques de l'eau , Polluants chimiques de l'eau/analyse , Polluants chimiques de l'eau/composition chimique , Chromatographie en phase liquide à haute performance , Thiazépines/composition chimique , Thiazépines/analyse , Rivières/composition chimique , Cinétique , Lumière du soleil
10.
Chemosphere ; 361: 142484, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38830465

RÉSUMÉ

The natural phototransformation of organic pollutants in the environment depends on several water constituents, including inorganic ions, humic substances, and pH. However, the literature information concerning the influence of various water components on the amount of phototransformation and their impact on the development of various transformation products (TPs) is minimal. This study investigated the phototransformation of ofloxacin (OFL), a fluoroquinolone antibiotic, in the presence of various water components such as cations (K+, Na+, Ca2+, NH4+, Mg2+), anions (NO3-, SO42-, HCO3-, CO32-, PO43-), pH, and humic substances when exposed to natural sunlight. The study reveals that neutral pH levels (0.39374 min⁻1) enhance the phototransformation of OFL in aquatic environments. Carbonate, among anions, shows the highest rate constant (2.89966 min⁻1), significantly influencing OFL phototransformation, while all anions exhibit a notable impact. In aquatic environments, indirect phototransformation of OFL, driven by increased reactive oxygen species, expedites light-induced reactions, potentially enhancing OFL phototransformation. A clear difference was visible in the type of transformation products (TPs) formed during direct and indirect photolysis. The impact of indirect photolysis in the product profile was evaluated by examining the unique properties of TPs in direct and indirect photolysis. The primary transformation products were generated by oxidation and cleavage processes directed towards the ofloxacin piperazinyl, oxazine, and carboxyl groups. The toxicity assessment of TPs derived from OFL revealed that among the 26 identified TPs, TP3 (demethylated product), TP7 and TP8 (decarboxylated products), and TP15 (piperazine ring cleaved product) could potentially have some toxicological effects. These findings suggest that the phototransformation of OFL in the presence of various water components is necessary when assessing this antibiotic's environmental fate.


Sujet(s)
Ofloxacine , Photolyse , Polluants chimiques de l'eau , Ofloxacine/composition chimique , Polluants chimiques de l'eau/composition chimique , Substances humiques/analyse , Lumière du soleil , Concentration en ions d'hydrogène , Antibactériens/composition chimique , Espèces réactives de l'oxygène/composition chimique
11.
PLoS One ; 19(6): e0306023, 2024.
Article de Anglais | MEDLINE | ID: mdl-38924003

RÉSUMÉ

Global warming is leading understory and canopy plant communities of temperate deciduous forests to grow leaves earlier in spring and drop them later in autumn. If understory species extend their leafy seasons less than canopy trees, they will intercept less light. We look for mismatched phenological shifts between canopy and understory in 28 years (1995-2022) of weekly data from Trelease Woods, Urbana, IL, USA. The observations cover 31 herb species of contrasting seasonality (for 1995-2017), three sapling species, and the 15 most dominant canopy tree species for all years, combined with solar radiation, temperature and canopy light transmittance data. We estimate how understory phenology, cold temperatures, canopy phenology, and solar radiation have individually limited understory plants' potential light interception over >2 decades. Understory and canopy phenology were the two factors most limiting to understory light availability, but which was more limiting varied greatly among species and among/within seasonality groups; solar radiation ranked third and cold fourth. Understory and canopy phenology shifts usually occurred in the same direction; either both strata were early or both were late, offsetting each other's effects. The four light-limiting factors combined showed significant temporal trends for six understory species, five toward less light interception. Warmer springs were significantly associated with shifts toward more light interception in three sapling species and 19 herb species. Canopy phenology became more limiting in warmer years for all three saplings species and 31 herb species. However, in aggregate, these variables mostly offset one another; only one sapling and seven herb species showed overall significant (and negative) relationships between light interception and spring temperature. The few understory species mismatched with canopy phenology due to changing climate are likely to intercept less light in future warmer years. The few species with data for carbon assimilation show broadly similar patterns to light interception.


Sujet(s)
Forêts , Saisons , Arbres , Arbres/croissance et développement , Arbres/physiologie , Changement climatique , Feuilles de plante/croissance et développement , Feuilles de plante/physiologie , Température , Lumière du soleil , Lumière , Climat
12.
Environ Monit Assess ; 196(7): 674, 2024 Jun 28.
Article de Anglais | MEDLINE | ID: mdl-38942963

RÉSUMÉ

Solar Fenton is an important and extensively used advanced oxidation process (AOP) to degrade pharmaceutical pollutants. The objective of this study was to evaluate the performance of simultaneous degradation of the mixed pollutants (amoxicillin, acetaminophen, and ciprofloxacin) for an aqueous solution using the solar Fenton process. Operating parameters such as pH, iron doses, H2O2 doses, pollutant concentrations, and time were studied. From the experimental results, the ideal conditions were obtained for the removal of mixed pollutants such as pH 3, Fe2+ 0.04 mM, H2O2 4 mM, the concentration of the mixed pollutants 5 mg/L, solar radiation 400 W/m2, and time 10 min, respectively. The pseudo-first-order kinetics were utilized to investigate the degradation efficacy of the mixed pollutants. The result of the study indicates that the degradation efficiency was > 99% for the mixed pollutants. A maximum of 63% mineralization was observed, and hydroxyl radical scavenger effects were studied. The best optimal conditions were applied to assess the spiked wastewater (municipal wastewater (MWW) and hospital wastewater (HWW)). The highest elimination rates for AMX, ACET, and CIP were observed as 65%, 89%, and 85% for MWW and 76%, 92%, and 80% for HWW, respectively. The degraded by-products were detected by LC-ESI-MS in the water matrix (aqueous solution and spiked wastewater), and ECOSAR analysis was performed for the transformed products. The study concluded that the solar Fenton technique is promising and effective for the removal of mixed pollutants from the water matrix.


Sujet(s)
Peroxyde d'hydrogène , Fer , Lumière du soleil , Élimination des déchets liquides , Polluants chimiques de l'eau , Polluants chimiques de l'eau/analyse , Polluants chimiques de l'eau/composition chimique , Peroxyde d'hydrogène/composition chimique , Cinétique , Fer/composition chimique , Élimination des déchets liquides/méthodes , Eaux usées/composition chimique , Oxydoréduction , Ciprofloxacine/composition chimique , Ciprofloxacine/analyse , Acétaminophène/composition chimique , Acétaminophène/analyse , Amoxicilline/composition chimique , Amoxicilline/analyse
14.
Dermatologie (Heidelb) ; 75(7): 518-527, 2024 Jul.
Article de Allemand | MEDLINE | ID: mdl-38864900

RÉSUMÉ

Solar urticaria is a rare idiopathic photodermatosis. According to the current knowledge its pathogenesis is most likely based on an allergic type I reaction to an autoantigen activated by ultraviolet (UV) radiation or visible light. As many of the patients suffer from severe forms of the disease, it may therefore severely impair the quality of life of those affected. In contrast, polymorphous light eruption is a very common disease, which, according to the current data, can be interpreted as a type IV allergic reaction to a photoallergen induced by UV radiation. As the skin lesions heal despite continued sun exposure, the patients' quality of life is generally not significantly impaired. These two clinically and pathogenetically very different light dermatoses have shared diagnostics by means of light provocation and an important therapeutic option (light hardening). Herein, we present an overview of the clinical picture, pathogenesis, diagnosis and available treatment options for the above-mentioned diseases.


Sujet(s)
Photodermatoses , Urticaire , Humains , Urticaire/étiologie , Urticaire/immunologie , Urticaire/diagnostic , Photodermatoses/diagnostic , Photodermatoses/étiologie , Photodermatoses/thérapie , Photodermatoses/immunologie , Lumière du soleil/effets indésirables , Rayons ultraviolets/effets indésirables , Dermatite photoallergique/diagnostic , Dermatite photoallergique/étiologie , Diagnostic différentiel , Urticaire solaire
15.
Environ Sci Pollut Res Int ; 31(29): 42034-42048, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38856854

RÉSUMÉ

The Red Sea is a hotspot of biodiversity susceptible to oil pollution. Besides, it is one of the warmest seas on the Earth with highly transparent waters. In this study, we estimated the oil dissolution rates under natural sunlight spectra and temperature conditions using coastal oil slicks collected after the 2019 Sabiti oil spill in the Red Sea. Optical analyses revealed the significant interactive effect of sunlight and temperature in enhancing the dissolution of oil into dissolved organic matter (DOM). The highest oil dissolution rate (38.68 g C m-3 d-1) was observed in full-spectrum sunlight. Oil dissolution significantly enhanced total organic carbon (TOC) and polycyclic aromatic hydrocarbons (PAHs) in seawater. High nucleic acid (HNA) bacteria, likely the oil degraders, proliferated from 30 to 70 - 90% after 4 days. The heavier stable carbon isotopic composition of methane (δ13C-CH4) and lighter stable carbon isotopic composition of carbon dioxide (δ13C-CO2) indicate the putative role of bacterial processes in the natural degradation of crude oil. The results indicated that the combined effect of temperature and solar radiation enhanced the biological and photochemical dissolution of oil on the Red Sea surface.


Sujet(s)
Pétrole , Lumière du soleil , Océan Indien , Pollution pétrolière , Température élevée , Eau de mer/composition chimique , Hydrocarbures aromatiques polycycliques/composition chimique , Polluants chimiques de l'eau/composition chimique
16.
Nature ; 631(8019): 111-117, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38898277

RÉSUMÉ

Amazonia contains the most extensive tropical forests on Earth, but Amazon carbon sinks of atmospheric CO2 are declining, as deforestation and climate-change-associated droughts1-4 threaten to push these forests past a tipping point towards collapse5-8. Forests exhibit complex drought responses, indicating both resilience (photosynthetic greening) and vulnerability (browning and tree mortality), that are difficult to explain by climate variation alone9-17. Here we combine remotely sensed photosynthetic indices with ground-measured tree demography to identify mechanisms underlying drought resilience/vulnerability in different intact forest ecotopes18,19 (defined by water-table depth, soil fertility and texture, and vegetation characteristics). In higher-fertility southern Amazonia, drought response was structured by water-table depth, with resilient greening in shallow-water-table forests (where greater water availability heightened response to excess sunlight), contrasting with vulnerability (browning and excess tree mortality) over deeper water tables. Notably, the resilience of shallow-water-table forest weakened as drought lengthened. By contrast, lower-fertility northern Amazonia, with slower-growing but hardier trees (or, alternatively, tall forests, with deep-rooted water access), supported more-drought-resilient forests independent of water-table depth. This functional biogeography of drought response provides a framework for conservation decisions and improved predictions of heterogeneous forest responses to future climate changes, warning that Amazonia's most productive forests are also at greatest risk, and that longer/more frequent droughts are undermining multiple ecohydrological strategies and capacities for Amazon forest resilience.


Sujet(s)
Résistance à la sécheresse , Sécheresses , Forêts , Nappe phréatique , Photosynthèse , Sol , Lumière du soleil , Arbres , Brésil , Séquestration du carbone , Sécheresses/statistiques et données numériques , Nappe phréatique/analyse , Sol/composition chimique , Arbres/classification , Arbres/métabolisme , Arbres/physiologie , Climat tropical , Résistance à la sécheresse/physiologie , Phylogéographie , Conservation des ressources naturelles
17.
Physiol Plant ; 176(4): e14410, 2024.
Article de Anglais | MEDLINE | ID: mdl-38945685

RÉSUMÉ

Maximal sunlight intensity varies diurnally due to the earth's rotation. Whether this slow diurnal pattern influences the photoprotective capacity of plants throughout the day is unknown. We investigated diurnal variation in NPQ, along with NPQ capacity, induction, and relaxation kinetics after transitions to high light, in tomato plants grown under diurnal parabolic (DP) or constant (DC) light intensity regimes. DP light intensity peaked at midday (470 µmol m-2 s-1) while DC stayed constant at 300 µmol m-2 s-1 at a similar 12-hour photoperiod and daily light integral. NPQs were higher in the morning and afternoon at lower light intensities in DP compared to DC, except shortly after dawn. NPQ capacity increased from midday to the end of the day, with higher values in DP than in DC. At high light ΦPSII did not vary throughout the day, while ΦNPQ varied consistently with NPQ capacity. Reduced ΦNO suggested less susceptibility to photodamage at the end of the day. NPQ induction was faster at midday than at the start of the day and in DC than in DP, with overshoot occurring in the morning and midday but not at the end of the day. NPQ relaxation was faster in DP than in DC. The xanthophyll de-epoxidation state and reduced demand for photochemistry could not explain the observed diurnal variations in photoprotective capacity. In conclusion, this study showed diurnal variation in regulated photoprotective capacity at moderate growth light intensity, which was not explained by instantaneous light intensity or increasing photoinhibition over the day and was influenced by acclimation to constant light intensity.


Sujet(s)
Rythme circadien , Lumière , Solanum lycopersicum , Solanum lycopersicum/effets des radiations , Solanum lycopersicum/physiologie , Solanum lycopersicum/métabolisme , Rythme circadien/physiologie , Rythme circadien/effets des radiations , Photosynthèse/effets des radiations , Photosynthèse/physiologie , Photopériode , Xanthophylles/métabolisme , Lumière du soleil , Chlorophylle/métabolisme , Complexe protéique du photosystème II/métabolisme , Cinétique , Feuilles de plante/effets des radiations , Feuilles de plante/physiologie , Feuilles de plante/métabolisme
18.
Nature ; 631(8020): 344-349, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38926575

RÉSUMÉ

Many threats to biodiversity cannot be eliminated; for example, invasive pathogens may be ubiquitous. Chytridiomycosis is a fungal disease that has spread worldwide, driving at least 90 amphibian species to extinction, and severely affecting hundreds of others1-4. Once the disease spreads to a new environment, it is likely to become a permanent part of that ecosystem. To enable coexistence with chytridiomycosis in the field, we devised an intervention that exploits host defences and pathogen vulnerabilities. Here we show that sunlight-heated artificial refugia attract endangered frogs and enable body temperatures high enough to clear infections, and that having recovered in this way, frogs are subsequently resistant to chytridiomycosis even under cool conditions that are optimal for fungal growth. Our results provide a simple, inexpensive and widely applicable strategy to buffer frogs against chytridiomycosis in nature. The refugia are immediately useful for the endangered species we tested and will have broader utility for amphibian species with similar ecologies. Furthermore, our concept could be applied to other wildlife diseases in which differences in host and pathogen physiologies can be exploited. The refugia are made from cheap and readily available materials and therefore could be rapidly adopted by wildlife managers and the public. In summary, habitat protection alone cannot protect species that are affected by invasive diseases, but simple manipulations to microhabitat structure could spell the difference between the extinction and the persistence of endangered amphibians.


Sujet(s)
Anura , Chytridiomycota , Résistance à la maladie , Espèce en voie de disparition , Mycoses , Refuge , Animaux , Anura/immunologie , Anura/microbiologie , Anura/physiologie , Température du corps/immunologie , Température du corps/physiologie , Température du corps/effets des radiations , Chytridiomycota/immunologie , Chytridiomycota/pathogénicité , Chytridiomycota/physiologie , Résistance à la maladie/immunologie , Résistance à la maladie/physiologie , Résistance à la maladie/effets des radiations , Écosystème , Mycoses/médecine vétérinaire , Mycoses/microbiologie , Mycoses/immunologie , Lumière du soleil , Animaux sauvages/immunologie , Animaux sauvages/microbiologie , Animaux sauvages/physiologie , Espèce introduite
19.
Environ Sci Pollut Res Int ; 31(30): 43211-43237, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38890253

RÉSUMÉ

Today's many giant sectors including energy, industry, tourism, and agriculture should closely track the variation trends of solar radiation to take more benefit from the sun. However, the scarcity of solar radiation measuring stations represents a significant obstacle. This has prompted research into the estimation of global solar radiation (GSR) for various regions using existing climatic and atmospheric parameters. While prediction methods cannot supplant the precision of direct measurements, they are invaluable for studying and utilizing solar energy on a global scale. From this point of view, this paper has focused on predicting daily GSR data in three provinces (Afyonkarahisar, Rize, and Agri) which exhibit disparate solar radiation distributions in Türkiye. In this context, Gradient-Based Optimizer (GBO), Harris Hawks Optimization (HHO), Barnacles Mating Optimizer (BMO), Sine Cosine Algorithm (SCA), and Henry Gas Solubility Optimization (HGSO) have been employed to model the daily GSR data. The algorithms were calibrated with daily historical data of five input variables including sunshine duration, actual pressure, moisture, wind speed, and ambient temperature between 2010 and 2017 years. Then, they were tested with daily data for the 2018 year. In the study, a series of statistical metrics (R2, MABE, RMSE, and MBE) were employed to elucidate the algorithm that predicts solar radiation data with higher accuracy. The prediction results demonstrated that all algorithms achieved the highest R2 value in Rize province. It has been found that SCA (MABE of 0.7023 MJ/m2, RMSE of 0.9121 MJ/m2, and MBE of 0.2430 MJ/m2) for Afyonkarahisar province and GBO (RMSE of 0.8432 MJ/m2, MABE of 0.6703 MJ/m2, and R2 of 0.8810) for Agri province are the most effective algorithms for estimating GSR data. The findings indicate that each of the metaheuristic algorithms tested in this paper has the potential to predict daily GSR data within a satisfactory error range. However, the GBO and SCA algorithms provided the most accurate predictions of daily GSR data.


Sujet(s)
Algorithmes , Climat , Lumière du soleil , Énergie solaire , Température
20.
Environ Geochem Health ; 46(7): 229, 2024 Jun 07.
Article de Anglais | MEDLINE | ID: mdl-38849639

RÉSUMÉ

Pesticide micropollutants like 4-chlorophenol (4CP) and E. coli bacteria represent a substantial hazard, impacting both the environment and human health. This study delves into the effectiveness of Ag-doped TiO2 (Ag@TiO2) in removing both 4CP and E. coli. Ag@TiO2 has demonstrated remarkable effectiveness in removing 4CP under both solar and visible light conditions, earning degradation efficiencies of 91.3% and 72.8%, respectively. Additionally, it demonstrates outstanding photodegradation efficiency for 4CP (98.8%) at an initial concentration of 1 mg L-1. Moreover, Ag@TiO2 exhibited substantially higher removal performance for 4CP (81.6%) compared to TiO2 (27.6%) in wastewater. Analysis of the radicals present during the photodegradation process revealed that ·O2- primarily drives the decomposition of 4CP, with h+ and ·OH also playing significant roles in the oxidation reactions of the pollutant. Interestingly, even under dark conditions, Ag@TiO2 exhibited the capability to eliminate approximately 20% of E. coli, a percentage that increased to over 96% under solar light. In addition, the prospects for environmental and health impacts of utilizing Ag@TiO2 for pesticide micropollutant removal and bacteria were discussed.


Sujet(s)
Chlorophénols , Escherichia coli , Pesticides , Argent , Lumière du soleil , Titane , Polluants chimiques de l'eau , Titane/composition chimique , Pesticides/composition chimique , Argent/composition chimique , Chlorophénols/composition chimique , Polluants chimiques de l'eau/composition chimique , Photolyse , Eaux usées/composition chimique
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