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1.
Sci Total Environ ; 926: 172114, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38561127

RESUMO

The microbial hosts of antibiotic resistance genes (ARGs) found epiphytically on plant materials could grow and flourish during silage fermentation. This study employed metagenomic analysis and elucidated the occurrence and transmission mechanisms of ARGs and their microbial hosts in whole-crop corn silage inoculated with homofermentative strain Lactiplantibacillus plantarum or heterofermentative strain Lentilactobacillus buchneri ensiled under different temperature (20 and 30 °C). The results revealed that the corn silage was dominated by Lactobacillus, Leuconostoc, Lentilactobacillus, and Latilactobacillus. Both the ensiling temperature and inoculation had greatly modified the silage microbiota. However, regardless of the ensiling temperature, L. buchneri had significantly higher ARGs, while it only exhibited significantly higher mobile genetic elements (MGEs) in low temperature treatments. The microbial community of the corn silage hosted highly diverse form of ARGs, which were primarily MacB, RanA, bcrA, msbA, TetA (58), and TetT and mainly corresponded to macrolides and tetracyclines drug classes. Plasmids were identified as the most abundant MGEs with significant correlation with some high-risk ARGs (tetM, TolC, mdtH, and NorA), and their abundances have been reduced by ensiling process. Furthermore, higher temperature and L. buchneri reduced abundances of high-risk ARGs by modifying their hosts and reduced their transmission in the silage. Therefore, ensiling, L. buchneri inoculation and higher storage temperature could improve the biosafety of corn silage.


Assuntos
Lactobacillales , Silagem , Silagem/análise , Silagem/microbiologia , Zea mays/microbiologia , Lactobacillales/genética , Antibacterianos , Temperatura , Fermentação
2.
Sci Total Environ ; 926: 172146, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38569963

RESUMO

Anthropogenic activities have led to the emergence of pharmaceutical pollution in marine ecosystems, posing a significant threat to biodiversity in conjunction with global climate change. While the ecotoxicity of human drugs on aquatic organisms is increasingly recognized, their interactions with environmental factors, such as temperature, remain understudied. This research investigates the physiological effects of the selective serotonin reuptake inhibitor (SSRI), fluoxetine, on two diatom species, Phaeodactylum tricornutum and Thalassiosira weissflogii. Results demonstrate that fluoxetine significantly reduces growth rate and biomass production, concurrently affecting pigment contents and the thermal performance curve (TPC) of the diatoms. Fluoxetine reduces the synthesis of chlorophyll a (Chl a) and carotenoid (Car), indicating inhibition of photosynthesis and photoprotection. Furthermore, fluoxetine decreases the maximum growth rate (µmax) while increasing the optimum temperature (Topt) in both species, suggesting an altered thermal plasticity. This shift is attributed to the observed decrease in the inhibition rate of fluoxetine with rising temperatures. These findings emphasize the physiological impacts and ecological implications of fluoxetine on phytoplankton and underscore the significance of considering interactions between multiple environmental drivers when accessing the ecotoxicity of potential pollutants. The present study provides insights into crucial considerations for evaluating the impacts of pharmaceutical pollution on marine primary producers.


Assuntos
Diatomáceas , Humanos , Diatomáceas/fisiologia , Clorofila A , Fluoxetina/toxicidade , Temperatura , Ecossistema , Preparações Farmacêuticas
3.
Zhongguo Zhen Jiu ; 44(4): 423-427, 2024 Apr 12.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38621730

RESUMO

OBJECTIVES: To observe the body surface temperature of the lumbosacral region and relevant back-shu points in patients with lumbar disc herniation (LDH) induced low back pain utilizing infrared thermography, and to explore the functional attribute changes of acupoints under pathological conditions. METHODS: A total of 50 patients with LDH induced low back pain were included as the observation group, and 45 healthy subjects were included as the control group. Using infrared thermography, the body surface temperature of the lumbosacral region and bilateral Sanjiaoshu (BL 22), Shenshu (BL 23), Qihaishu (BL 24), Dachangshu (BL 25), Guanyuanshu (BL 26), Xiaochangshu (BL 27), and Pangguangshu (BL 28) was measured in both groups. The temperature difference values between the bilateral lumbosacral regions and back-shu points of the two groups were calculated. Additionally, the body surface temperature of the affected and healthy sides of the lumbosacral region and relevant back-shu points was compared in the observation group. RESULTS: Compared with the control group, the body surface temperature of the lumbosacral region and the bilateral temperature difference values of the lumbosacral regions were increased in the observation group (P<0.001). The body surface temperature difference values of bilateral Shenshu (BL 23), Qihaishu (BL 24), Dachangshu (BL 25), Guanyuanshu (BL 26) and Xiaochangshu (BL 27) in the observation group were higher than those in the control group (P<0.05, P<0.01, P<0.001). In the observation group, the body surface temperature of the affected side of the lumbosacral region as well as Shenshu (BL 23) and Dachangshu (BL 25) was elevated compared with that of healthy side (P<0.001). CONCLUSIONS: The patients with LDH induced low back pain have imbalanced and asymmetrical distribution of body surface temperature in the lumbosacral region and related back-shu points, Shenshu (BL 23) and Dachangshu (BL 25) have the relative specificity.


Assuntos
Deslocamento do Disco Intervertebral , Dor Lombar , Humanos , Deslocamento do Disco Intervertebral/terapia , Dor Lombar/etiologia , Dor Lombar/terapia , Região Lombossacral , Temperatura , Termografia , Pontos de Acupuntura
4.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1196-1205, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621966

RESUMO

Processing of Chinese medicinal materials is an important part in the Chinese medicine heritage, and the temperature control in the processing has a direct impact on the quality and efficacy of traditional Chinese medicines. However, the processing of Chinese medicinal materials has the problems of subjective temperature judgement, determination of the end point based on experience, unclear processing mechanism, unstable quality of products, and inconsistent processing standards. The temperature control in the processing is reflected in the appearance and internal quality of Chinese medicinal materials. The theory of quality evaluation through morphological identification is developed based on the comprehensive evaluation of the shape, color, taste, and components, which is associated with the temperature control in the processing. To solve the problems above, this paper puts forward the following solutions. The first is literature mining. By review of the ancient medical works and pharmaceutical experience, the temperature control in processing and the evolution of processing methods can be revealed. Second, according to the ancient method, the processing principle can be explored, on the basis of which the processing technology can be innovated. Third, the standard operating procedure(SOP) should be established to quantify the fire temperature, providing a theoretical basis for the formulation of Chinese medicinal material processing standards. Moreover, it provides a basis for improving the quality of processed products and increasing the safety and effectiveness of traditional Chinese medicines.


Assuntos
Medicamentos de Ervas Chinesas , Humanos , Temperatura , Medicina Tradicional Chinesa , Padrões de Referência , Tecnologia
5.
Environ Health ; 23(1): 40, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622704

RESUMO

BACKGROUND: Western Montana, USA, experiences complex air pollution patterns with predominant exposure sources from summer wildfire smoke and winter wood smoke. In addition, climate change related temperatures events are becoming more extreme and expected to contribute to increases in hospital admissions for a range of health outcomes. Evaluating while accounting for these exposures (air pollution and temperature) that often occur simultaneously and may act synergistically on health is becoming more important. METHODS: We explored short-term exposure to air pollution on children's respiratory health outcomes and how extreme temperature or seasonal period modify the risk of air pollution-associated healthcare events. The main outcome measure included individual-based address located respiratory-related healthcare visits for three categories: asthma, lower respiratory tract infections (LRTI), and upper respiratory tract infections (URTI) across western Montana for ages 0-17 from 2017-2020. We used a time-stratified, case-crossover analysis with distributed lag models to identify sensitive exposure windows of fine particulate matter (PM2.5) lagged from 0 (same-day) to 14 prior-days modified by temperature or season. RESULTS: For asthma, increases of 1 µg/m3 in PM2.5 exposure 7-13 days prior a healthcare visit date was associated with increased odds that were magnified during median to colder temperatures and winter periods. For LRTIs, 1 µg/m3 increases during 12 days of cumulative PM2.5 with peak exposure periods between 6-12 days before healthcare visit date was associated with elevated LRTI events, also heightened in median to colder temperatures but no seasonal effect was observed. For URTIs, 1 unit increases during 13 days of cumulative PM2.5 with peak exposure periods between 4-10 days prior event date was associated with greater risk for URTIs visits that were intensified during median to hotter temperatures and spring to summer periods. CONCLUSIONS: Delayed, short-term exposure increases of PM2.5 were associated with elevated odds of all three pediatric respiratory healthcare visit categories in a sparsely population area of the inter-Rocky Mountains, USA. PM2.5 in colder temperatures tended to increase instances of asthma and LRTIs, while PM2.5 during hotter periods increased URTIs.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Asma , Infecções Respiratórias , Criança , Humanos , Estados Unidos/epidemiologia , Material Particulado/efeitos adversos , Material Particulado/análise , Temperatura , Estações do Ano , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Fumaça/efeitos adversos , Asma/epidemiologia , Montana/epidemiologia , Exposição Ambiental/análise
6.
Ecol Lett ; 27(4): e14405, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38623056

RESUMO

Local adaptation is commonly cited to explain species distribution, but how fitness varies along continuous geographical gradients is not well understood. Here, we combine thermal biology and life-history theory to demonstrate that Drosophila populations along a 2500 km latitudinal cline are adapted to local conditions. We measured how heat tolerance and viability rate across eight populations varied with temperature in the laboratory and then simulated their expected cumulative Darwinian fitness employing high-resolution temperature data from their eight collection sites. Simulations indicate a trade-off between annual survival and cumulative viability, as both mortality and the recruitment of new flies are predicted to increase in warmer regions. Importantly, populations are locally adapted and exhibit the optimal combination of both traits to maximize fitness where they live. In conclusion, our method is able to reconstruct fitness surfaces employing empirical life-history estimates and reconstructs peaks representing locally adapted populations, allowing us to study geographic adaptation in silico.


Assuntos
Adaptação Fisiológica , Drosophila , Animais , Aclimatação , Temperatura , Aptidão Genética
7.
J Mol Model ; 30(5): 134, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625615

RESUMO

CONTENT: Ubiquitin, a ubiquitous small protein found in all living organisms, is crucial for tagging proteins earmarked for degradation and holds pivotal importance in biomedicine. Protein functionality is intricately linked to its structure. To comprehend the impact of diverse temperatures on ubiquitin protein structure, our study delved into the energy landscape, hydrogen bonding, and overall structural stability of ubiquitin protein at varying temperatures. Through meticulous analysis of root mean square deviation and root mean square fluctuation, we validated the robustness of the simulation conditions employed. Within our simulated system, the bonding energy and electrostatic potential energy exhibited linear augmentation, while the van der Waals energy demonstrated a linear decline. Additionally, our findings highlighted that the α-Helix secondary structure of the ubiquitin protein gradually transitions toward helix destabilization under high-temperature conditions. The secondary structure of ubiquitin protein experiences distinct changes under varying temperatures. The outcomes of our molecular simulations offer a theoretical framework that enhances our comprehension of how temperature impacts the structural stability of ubiquitin protein. These insights contribute not only to a deeper understanding of iniquity's behavior but also hold broader implications in the realm of biomedicine and beyond. METHODS: All the MD simulations were performed using the GROMACS software with GROMOS96 force field and SPC for water. The ubiquitin protein was put in the center of a cubic box with a length of 8 nm, a setting that allowed > 0.8 nm in the minimal distance between the protein surface and the box wall. To remove the possible coordinate collision of the configurations, in the beginning, the steepest descent method was used until the maximum force between atoms was under 100 kJ/mol·nm with a 0.01 nm step size. Minimization was followed by 30 ps of position-restrained MD simulation. The protein was restrained to its initial position, and the solvent was freely equilibrated. The product phase was obtained with the whole system simulated for 10 ns without any restraint using an integral time step of 1 fs with different temperatures. The cutoff for short-range electronic interaction was set to 1.5 nm. The long-range interactions were treated with a particle-mesh Ewald (PME) method with a grid width of 1.2 nm.


Assuntos
Simulação de Dinâmica Molecular , Ubiquitina , Temperatura , Proteínas de Membrana , Conformação Molecular
8.
Proc Natl Acad Sci U S A ; 121(15): e2309087121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557184

RESUMO

Africa carries a disproportionately high share of the global malaria burden, accounting for 94% of malaria cases and deaths worldwide in 2019. It is also a politically unstable region and the most vulnerable continent to climate change in recent decades. Knowledge about the modifying impacts of violent conflict on climate-malaria relationships remains limited. Here, we quantify the associations between violent conflict, climate variability, and malaria risk in sub-Saharan Africa using health surveys from 128,326 individuals, historical climate data, and 17,429 recorded violent conflicts from 2006 to 2017. We observe that spatial spillovers of violent conflict (SSVCs) have spatially distant effects on malaria risk. Malaria risk induced by SSVCs within 50 to 100 km from the households gradually increases from 0.1% (not significant, P>0.05) to 6.5% (95% CI: 0 to 13.0%). SSVCs significantly promote malaria risk within the average 20.1 to 26.9 °C range. At the 12-mo mean temperature of 22.5 °C, conflict deaths have the largest impact on malaria risk, with an approximately 5.8% increase (95% CI: 1.0 to 11.0%). Additionally, a pronounced association between SSVCs and malaria risk exists in the regions with 9.2 wet days per month. The results reveal that SSVCs increase population exposure to harsh environments, amplifying the effect of warm temperature and persistent precipitation on malaria transmission. Violent conflict therefore poses a substantial barrier to mosquito control and malaria elimination efforts in sub-Saharan Africa. Our findings support effective targeting of treatment programs and vector control activities in conflict-affected regions with a high malaria risk.


Assuntos
Exposição à Violência , Malária , Humanos , Malária/epidemiologia , África Subsaariana/epidemiologia , Temperatura
9.
Sci Rep ; 14(1): 8773, 2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627532

RESUMO

Previous studies have primarily focused on the influence of temperature and precipitation on phenology. It is unclear if the easily ignored climate factors with drivers of vegetation growth can effect on vegetation phenology. In this research, we conducted an analysis of the start (SOS) and end (EOS) of the growing seasons in the northern region of China above 30°N from 1982 to 2014, focusing on two-season vegetation phenology. We examined the response of vegetation phenology of different vegetation types to preseason climatic factors, including relative humidity (RH), shortwave radiation (SR), maximum temperature (Tmax), and minimum temperature (Tmin). Our findings reveal that the optimal preseason influencing vegetation phenology length fell within the range of 0-60 days in most areas. Specifically, SOS exhibited a significant negative correlation with Tmax and Tmin in 44.15% and 42.25% of the areas, respectively, while EOS displayed a significant negative correlation with SR in 49.03% of the areas. Additionally, we identified that RH emerged as the dominant climatic factor influencing the phenology of savanna (SA), whereas temperature strongly controlled the SOS of deciduous needleleaf forest (DNF) and deciduous broadleaf forest (DBF). Meanwhile, the EOS of DNF was primarily influenced by Tmax. In conclusion, this study provides valuable insights into how various vegetation types adapt to climate change, offering a scientific basis for implementing effective vegetation adaptation measures.


Assuntos
Florestas , Desenvolvimento Vegetal , China , Mudança Climática , Estações do Ano , Temperatura , Ecossistema
10.
BMC Genomics ; 25(1): 370, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627628

RESUMO

BACKGROUND: Quinoa (Chenopodium quinoa Willd.) is valued for its nutritional richness. However, pre-harvest sprouting poses a significant threat to yield and grain quality. This study aims to enhance our understanding of pre-harvest sprouting mitigation strategies, specifically through delayed sowing and avoiding rainy seasons during quinoa maturation. The overarching goal is to identify cold-resistant varieties and unravel the molecular mechanisms behind the low-temperature response of quinoa. We employed bioinformatics and genomics tools for a comprehensive genome-wide analysis of polyamines (PAs) and ethylene synthesis gene families in quinoa under low-temperature stress. RESULTS: This involved the identification of 37 PA biosynthesis and 30 PA catabolism genes, alongside 227 ethylene synthesis. Structural and phylogenetic analyses showcased conserved patterns, and subcellular localization predictions indicated diverse cellular distributions. The results indicate that the PA metabolism of quinoa is closely linked to ethylene synthesis, with multiple genes showing an upregulation in response to cold stress. However, differential expression within gene families suggests a nuanced regulatory network. CONCLUSIONS: Overall, this study contributes valuable insights for the functional characterization of the PA metabolism and ethylene synthesis of quinoa, which emphasize their roles in plant low-temperature tolerance and providing a foundation for future research in this domain.


Assuntos
Chenopodium quinoa , Chenopodium quinoa/genética , Chenopodium quinoa/metabolismo , Filogenia , Temperatura , Poliaminas/metabolismo , Etilenos/metabolismo
11.
Platelets ; 35(1): 2337255, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38630028

RESUMO

Exosomes carry large cargo of proteins, lipids, and nucleic acids, serving as versatile biomarkers for disease diagnosis and vehicles for drug delivery. However, up to date, no well recognized standard procedures for exosome storage were available for clinical application. This study aimed to determine the optimal storage conditions and the anticoagulants for plasma-derived exosome isolation. Fresh whole blood samples were collected from healthy participants and preserved in four different anticoagulants including sodium citrate (SC1/4), sodium citrate (SC1/9), lithium heparin (LH), or Ethylenediamine tetraacetic acid (EDTA), respectively. Exosomes were extracted from the plasma by differential ultracentrifugation and stored at three different temperatures, 4°C, -20°C or - 80°C for a duration ranging from one week to six months. All plasma samples for storage conditions comparison were pretreated with LH anticoagulant. Exosome features including morphological characteristics, pariticles size diameter, and surface protein profiles (TSG101, CD63, CD81, CD9, CALNEXIN) were assessed by transmission electron microscopy, Nanoparticle Tracking Analysis, and Western Blotting, respectively. Exosomes preserved in LH and SC1/4 group tended to remain intact microstructure with highly abundant protein biomarkers. Exosomes stored at 4°C for short time were prone to be more stable compared to thos at -80°C. Exosomes stored in plasma were superior in terms of ultrastructure, size diameter and surface protein expression to those stored in PBS. In conclusion, plasma-dervied exosome characteristics strictly depend on the anticoagulants and storage temperature and duration.


What is the context? Effective isolation of exosomes is a prerequisite for subsequent investigation into its involvemnt in disease development as well as potentialtherapeutic applications.Anticoagulants, storage temperature and durations might change the microscopical structure, integrity and also the stability of plasma-derived exosomes. However, no internationally recognized standard of exosome storage procedure was available for clinical use.What is new? Our finding evaluated the effect of anticoagulants and storage on plasma exosome characteristics.Exosomes isolated from plasma preserved with Li-heparin and sodium citrate (1/4) showed better physical properties and surface marker protein expression.Isolated exosomes appeared more stable in a short time for 4°C compared to −80°C. Storage of exosomes in plasma showed better physical properties and surface marker protein expression than in PBS.What is the impact? Our findings inform the significance of standardizing procedure of exosome isolation and preservation.


Assuntos
Exossomos , Humanos , Citrato de Sódio , Temperatura , Anticoagulantes/farmacologia , Anticoagulantes/uso terapêutico , Heparina , Proteínas de Membrana , Biomarcadores
12.
Plant Mol Biol ; 114(3): 44, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630172

RESUMO

Albino tea cultivars have high economic value because their young leaves contain enhanced free amino acids that improve the quality and properties of tea. Zhonghuang 1 (ZH1) and Zhonghuang 2 (ZH2) are two such cultivars widely planted in China; however, the environmental factors and molecular mechanisms regulating their yellow-leaf phenotype remain unclear. In this study, we demonstrated that both ZH1 and ZH2 are light- and temperature-sensitive. Under natural sunlight and low-temperature conditions, their young shoots were yellow with decreased chlorophyll and an abnormal chloroplast ultrastructure. Conversely, young shoots were green with increased chlorophyll and a normal chloroplast ultrastructure under shading and high-temperature conditions. RNA-seq analysis was performed for high light and low light conditions, and pairwise comparisons identified genes exhibiting different light responses between albino and green-leaf cultivars, including transcription factors, cytochrome P450 genes, and heat shock proteins. Weighted gene coexpression network analyses of RNA-seq data identified the modules related to chlorophyll differences between cultivars. Genes involved in chloroplast biogenesis and development, light signaling, and JA biosynthesis and signaling were typically downregulated in albino cultivars, accompanied by a decrease in JA-ILE content in ZH2 during the albino period. Furthermore, we identified the hub genes that may regulate the yellow-leaf phenotype of ZH1 and ZH2, including CsGDC1, CsALB4, CsGUN4, and a TPR gene (TEA010575.1), which were related to chloroplast biogenesis. This study provides new insights into the molecular mechanisms underlying leaf color formation in albino tea cultivars.


Assuntos
Albinismo , Perfilação da Expressão Gênica , Temperatura , Temperatura Baixa , Clorofila
13.
World J Microbiol Biotechnol ; 40(6): 169, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630389

RESUMO

Mannan is a predominant constituent of cork hemicellulose and is widely distributed in various plant tissues. ß-Mannanase is the principal mannan-degrading enzyme, which breaks down the ß-1,4-linked mannosidic bonds in mannans in an endo-acting manner. Microorganisms are a valuable source of ß-mannanase, which exhibits catalytic activity in a wide range of pH and temperature, making it highly versatile and applicable in pharmaceuticals, feed, paper pulping, biorefinery, and other industries. Here, the origin, classification, enzymatic properties, molecular modification, immobilization, and practical applications of microbial ß-mannanases are reviewed, the future research directions for microbial ß-mannanases are also outlined.


Assuntos
Mananas , beta-Manosidase , beta-Manosidase/genética , Temperatura
14.
Int J Biol Macromol ; 265(Pt 2): 131260, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38599904

RESUMO

Preconditioning processes in proteins play a crucial role in enhancing their functional properties as surface active agents. Whey protein isolate (WPI, 20 wt%) was preconditioned via temperature (WPIT, 90 °C) or ultrasound (WPIUS, 20 kHz, 80 % amplitude). FTIR and zeta potential analysis demonstrated the effect of the preconditioning process on the secondary structure and surface properties of WPI. WPI-Alginate:Inulin (AI) complex coacervates (CCWPI:AI) were formed at pH 3.0 using WPIT and WPIUS, and the associative electrostatic interactions between WPI-AI led to coacervation yields >90 %, influenced by the preconditioning process employed. Viscoelastic properties outlined a predominantly solid-like behavior (G´ > G"). The CCWPI:AI system based on WPIT showed enhanced strength and gel-like structure compared to the WPIUS-based system. Oil-in-water (O/W) emulgels were formed and stabilized with the CCWPI:AI complexes, exhibiting spherical droplets (93.3-292.8 µm), whereas texture and rheological properties highlighted the formation of gel-like systems. The centrifugation STEP technology was used to evaluate the physical stability of emulgels, WPIT-based emulgels displayed superior stability against creaming than untreated WPI and WPIUS-based emulgels. These findings provide a basis for developing emulgels with prolonged stability and tunable functional properties, tailoring enhanced viscoelastic and texture attributes to meet specific needs for industrial applications where gel-like properties are pursued.


Assuntos
Inulina , Proteínas do Soro do Leite/química , Temperatura , Emulsões/química
15.
Nat Commun ; 15(1): 3219, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622143

RESUMO

Diverse aerobic bacteria use atmospheric hydrogen (H2) and carbon monoxide (CO) as energy sources to support growth and survival. Such trace gas oxidation is recognised as a globally significant process that serves as the main sink in the biogeochemical H2 cycle and sustains microbial biodiversity in oligotrophic ecosystems. However, it is unclear whether archaea can also use atmospheric H2. Here we show that a thermoacidophilic archaeon, Acidianus brierleyi (Thermoproteota), constitutively consumes H2 and CO to sub-atmospheric levels. Oxidation occurs across a wide range of temperatures (10 to 70 °C) and enhances ATP production during starvation-induced persistence under temperate conditions. The genome of A. brierleyi encodes a canonical CO dehydrogenase and four distinct [NiFe]-hydrogenases, which are differentially produced in response to electron donor and acceptor availability. Another archaeon, Metallosphaera sedula, can also oxidize atmospheric H2. Our results suggest that trace gas oxidation is a common trait of Sulfolobales archaea and may play a role in their survival and niche expansion, including during dispersal through temperate environments.


Assuntos
Acidianus , Archaea , Temperatura , Ecossistema , Oxirredução , Hidrogênio
16.
PLoS One ; 19(4): e0299468, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625873

RESUMO

In this paper, a daily gridded observation data across China from 1961 to 2022 were used to calculate daily potential evapotranspiration (PET). The observed variables included daily temperature, sunshine hours, average wind speed, and average relative humidity. PET was determined using the Penman-Monteith method recommended by the Food and Agriculture Organization (FAO). The long-term trend of PET was investigated in six regions of China during different seasons. To further compressed the influence of various meteorological factors on the PET trend, the contribution of each meteorological element to the long-term trend of PET was analyzed. The results indicate the following: (1) PET reaches its peak during summer which values from 145 to 640 mm, while it is lowest during winter from 21 to 244 mm. (2) The spatial patterns of PET trend changes are relatively similar across the four seasons, characterized by a decrease in the eastern regions and an increase in the western regions. The reduction is most significant during the summer and the range of trend is from -2.04 to 1.48 mm/day, while the increase becomes more pronounced in the winter which trend is from -0.34 to 0.53 mm/day. (3) The contribution of factors varies significantly across different regions. In spring and autumn, RH and U have little difference in contribution from other factors. But tsun is varies different from regions, the contribution value is largest in the northwest and smallest in the northeast. However, during summer, tsun become the most significant contributor in the YZ and SE regions, while in winter, Tm emerges as the most significant contributor to the PET trend in all six subregions. In SW, the contribution from U2 is the smallest in all seasons, with RH and Tm being the two crucial factors determining the PET trend in this region.


Assuntos
Produtos Agrícolas , Vento , Estações do Ano , Temperatura , China
17.
PLoS One ; 19(4): e0297750, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625921

RESUMO

High-voltage dry-type bushings, serving as the crucial junctions in DC power transmission, represent equipment with the highest failure rate on the DC primary side, underscoring the critical importance of monitoring their condition. Presently, numerical simulation methods are commonly employed to assess the internal state of bushings. However, due to limitations in the efficiency of multi-physics field computations, the guidance provided by numerical simulation results in the field of power equipment condition assessment is relatively weak. This paper focuses on solving the electrical-thermal coupling in high-voltage dry-type bushings. Addressing the most widely used tetrahedral mesh in numerical computations, we propose an efficient solution method based on the concept of "smooth domains." This method involves partitioning the volume centroids of the elements into multiple smooth domains within the computational domain. Electric and thermal conduction matrix calculations occur within these smooth domains, rather than within the grid or element interiors. This approach eliminates the need for traditional element mapping and complex volume integration. To demonstrate the effectiveness of this method, we use high-voltage dry-type bushings as a case study, comparing the performance of our approach with traditional finite element algorithms. We verify the algorithm's computational efficiency and apply it to the analysis of typical temperature anomalies in bushings, further illustrating its suitability for electrical equipment condition assessment.


Assuntos
Algoritmos , Eletricidade , Simulação por Computador , Temperatura , Sistemas Computacionais , Análise de Elementos Finitos
18.
Proc Natl Acad Sci U S A ; 121(17): e2316646121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38625943

RESUMO

Circadian regulation and temperature dependency are important orchestrators of molecular pathways. How the integration between these two drivers is achieved, is not understood. We monitored circadian- and temperature-dependent effects on transcription dynamics of cold-response protein RNA Binding Motif 3 (Rbm3). Temperature changes in the mammalian master circadian pacemaker, the suprachiasmatic nucleus (SCN), induced Rbm3 transcription and regulated its circadian periodicity, whereas the core clock gene Per2 was unaffected. Rbm3 induction depended on a full Brain And Muscle ARNT-Like Protein 1 (Bmal1) complement: reduced Bmal1 erased Rbm3 responses and weakened SCN circuit resilience to temperature changes. By focusing on circadian and temperature dependency, we highlight weakened transmission between core clock and downstream pathways as a potential route for reduced circadian resilience.


Assuntos
Ritmo Circadiano , Proteínas Circadianas Period , Animais , Ritmo Circadiano/fisiologia , Temperatura , Proteínas Circadianas Period/metabolismo , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , RNA/metabolismo , Núcleo Supraquiasmático/metabolismo , Mamíferos/genética
19.
Sci Rep ; 14(1): 8237, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589450

RESUMO

Coffee professionals have long known that the "roast profile," i.e., the temperature versus time inside the roaster, strongly affects the flavor and quality of the coffee. A particularly important attribute of brewed coffee is the perceived sourness, which is known to be strongly correlated to the total titratable acidity (TA). Most prior work has focused on laboratory-scale roasters with little control over the roast profile, so the relationship between roast profile in a commercial-scale roaster and the corresponding development of TA to date remains unclear. Here we investigate roast profiles of the same total duration but very different dynamics inside a 5-kg commercial drum roaster, and we show that the TA invariably peaks during first crack and then decays to its original value by second crack. Although the dynamics of the TA development varied with roast profile, the peak TA surprisingly exhibited almost no statistically significant differences among roast profiles. Our results provide insight on how to manipulate and achieve desired sourness during roasting.


Assuntos
Coffea , Temperatura Alta , Temperatura , Tempo
20.
Sci Rep ; 14(1): 8235, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589665

RESUMO

This study investigated the germination capacity (endogenous factor) of Petagnaea gussonei (Spreng.) Rauschert, an endemic monospecific plant considered as a relict species of the ancient Mediterranean Tertiary flora. This investigation focused also on the temporal trends of soil-use, climate and desertification (exogenous factors) across the natural range of P. gussonei. The final germination percentage showed low values between 14 and 32%, the latter obtained with GA3 and agar at 10 °C. The rising temperatures in the study area will further increase the dormancy of P. gussonei, whose germination capacity was lower and slower at temperatures higher than 10 °C. A further limiting factor of P. gussonei is its dormancy, which seems to be morpho-physiological. Regarding climate trends, in the period 1931-2020, the average temperature increased by 0.5 °C, from 15.4 to 15.9 °C, in line with the projected climate changes throughout the twenty-first century across the Mediterranean region. The average annual rainfall showed a relatively constant value of c. 900 mm, but extreme events grew considerably in the period 1991-2020. Similarly, the land affected by desertification expanded in an alarming way, by increasing from 21.2% in 2000 to 47.3% in 2020. Soil-use changes created also a complex impacting mosaic where c. 40% are agricultural areas. The effective conservation of P. gussonei should be multilateral by relying on germplasm banks, improving landscape connectivity and vegetation cover, and promoting climate policies.


Assuntos
Apiaceae , Dormência de Plantas , Dormência de Plantas/fisiologia , Solo , Conservação dos Recursos Naturais , Mudança Climática , Sementes/fisiologia , Germinação/fisiologia , Plantas , Temperatura
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