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1.
Skin Res Technol ; 30(4): e13675, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38558144

RESUMO

AIMS: This research assessed the safety of aqueous ozone (AO) on human skin after multiple exposures for up to 40 hours. METHODS AND RESULTS: Full thickness recombinant human skin (EpiDerm FT, EFT-400) was exposed to AO for 7 seconds per minute for the first 6 minutes of each hour, repeated hourly over four time periods (4, 10, 20 and 40 hours). An MTT assay assessed viability of skin cells after exposure, compared to incubator control, negative control and vehicle control (distilled water). No significant difference in tissue viability was found between the AO condition and any of the control conditions through 20 hours of exposures. At 40 hours of exposure, tissue viability was lower in the AO group when compared with negative control (p = 0.030) but not the other controls. CONCLUSIONS: The current study supports further consideration of repeated application of AO on human skin, such as for hand hygiene. IMPACT STATEMENT: The present research is the first well-controlled in vitro study assessing the cytotoxicity of repeated exposures of AO on a full-thickness human skin model. This information helps to inform the evaluation of AO as a potential alternative for hand and wound antisepsis.


Assuntos
Higiene das Mãos , Ozônio , Humanos , Ozônio/toxicidade , Pele , Epiderme , Água
2.
PeerJ ; 12: e17190, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560461

RESUMO

Maize production and productivity are affected by drought stress in tropical and subtropical ecologies, as the majority of the area under maize cultivation in these ecologies is rain-fed. The present investigation was conducted to study the physiological and biochemical effects of 24-Epibrassinolide (EBR) as a plant hormone on drought tolerance in maize. Two maize hybrids, Vivek hybrid 9 and Bio 9637, were grown under three different conditions: (i) irrigated, (ii) drought, and (iii) drought+EBR. A total of 2 weeks before the anthesis, irrigation was discontinued to produce a drought-like condition. In the drought+EBR treatment group, irrigation was also stopped, and in addition, EBR was applied as a foliar spray on the same day in the drought plots. It was observed that drought had a major influence on the photosynthesis rate, membrane stability index, leaf area index, relative water content, and leaf water potential; this effect was more pronounced in Bio 9637. Conversely, the activities of antioxidant enzymes such as catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) increased in both hybrids under drought conditions. Specifically, Vivek hybrid 9 showed 74% higher CAT activity under drought conditions as compared to the control. Additionally, EBR application further enhanced the activity of this enzyme by 23% compared to plants under drought conditions. Both hybrids experienced a significant reduction in plant girth due to drought stress. However, it was found that exogenously applying EBR reduced the detrimental effects of drought stress on the plant, and this effect was more pronounced in Bio 9637. In fact, Bio 9637 treated with EBR showed an 86% increase in proline content and a 70% increase in glycine betaine content compared to untreated plants under drought conditions. Taken together, our results suggested EBR enhanced tolerance to drought in maize hybrids. Hence, pre-anthesis foliar application of EBR might partly overcome the adverse effects of flowering stage drought in maize.


Assuntos
Brassinosteroides , Esteroides Heterocíclicos , Estresse Fisiológico , Zea mays , Secas , Antioxidantes/farmacologia , Água/farmacologia
3.
Sci Rep ; 14(1): 7653, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561458

RESUMO

Freshwater mussels preserve valuable information about hydrology, climate, and population dynamics, but developing seasonal chronologies can be problematic. Using clumped isotope thermometry, we produced high-resolution reconstructions of modern and historic (~ 1900) temperatures and δ18Owater from mussel shells collected from an impounded river, the Brazos in Texas, before and after damming. We also performed high-resolution growth band analyses to investigate relationships between mussel growth rate, rainfall, and seasonal temperature. Reconstructed δ18Owater and temperature vary little between the modern (3R5) and historic shell (H3R). However, a positive relationship between reconstructed δ18Owater and growth rate in H3R indicates that aside from diminished growth in winter, precipitation and flow rate are the strongest controls on mussel growth in both modern and pre-dam times. Overall, our results demonstrate (1) the impact, both positive and negative, of environmental factors such as flow alteration and temperature on mussel growth and (2) the potential for clumped isotopes in freshwater mussels as a paleohydrology and paleoclimate proxies in terrestrial environments.


Assuntos
Bivalves , Rios , Animais , Clima , Isótopos de Oxigênio/análise , Água
4.
Environ Monit Assess ; 196(5): 409, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564102

RESUMO

The amount of information available on the microplastic (MP) contamination in Goa's riverine water systems is currently limited. The abundance, size, colour, and polymer composition of microplastics in Chapora River surface water were investigated in this study. MPs in Chapora River surface water ranged from 0.1 particles/L (station 13) to 0.47 particles/L (station 5). The mean (± standard deviation) MP concentration was 0.25 (± 0.13) particles/L. Fibre was the dominant shape (77.15%), followed by fragments (12.36%), films (9.36%), and foam (1.12%). Most MPs were found in the 0.1-0.3 mm size range, then in the 0.3-1 mm and 1-5 mm. The dominant type of polymer studied was polyethylene terephthalate (PET; 46%), followed by high-density polyethylene (HDPE; 14%), polypropylene (PP; 5%), and polystyrene (PS; 1%). The risk assessment study indicated high risk with respect to PHI, while PLI shows low risk in the area. The source of MPs was mostly anthropogenic in nature in the region. When compared with other tropical rivers, MP pollution was relatively lower in the Chapora River. Nevertheless, the baseline data will help the local administration take mitigation measures to reduce the impact of MP pollution in the region.


Assuntos
Microplásticos , Rios , Plásticos , Monitoramento Ambiental , Medição de Risco , Índia , Polietileno , Polímeros , Água
5.
Physiol Plant ; 176(2): e14265, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556740

RESUMO

Plant species distribution across ecosystems is influenced by multiple environmental factors, and recurrent seasonal stress events can act as natural selection agents for specific plant traits and limit species distribution. For that, studies aiming at understanding how environmental constraints affect adaptive mechanisms of taxonomically closely related species are of great interest. We chose two Scabiosa species inhabiting contrasting environments: the coastal scabious S. atropurpurea, typically coping with hot-dry summers in a Mediterranean climate, and the mountain scabious S. columbaria facing cold winters in an oceanic climate. A set of functional traits was examined to assess plant performance in these congeneric species from contrasting natural habitats. Both S. atropurpurea and S. columbaria appeared to be perfectly adapted to their environment in terms of adjustments in stomatal closure, CO2 assimilation rate and water use efficiency over the seasons. However, an unexpected dry period during winter followed by the typical Mediterranean hot-dry summer forced S. atropurpurea plants to deploy a set of photoprotective responses during summer. Aside from reductions in leaf water content and Fv/Fm, photoprotective molecules (carotenoids, α-tocopherol and anthocyanins) per unit of chlorophyll increased, mostly as a consequence of a severe chlorophyll loss. The profiling of stress-related hormones (ABA, salicylic acid and jasmonates) revealed associations between ABA and the bioactive jasmonoyl-isoleucine with the underlying photoprotective response to recurrent seasonal stress in S. atropurpurea. We conclude that jasmonates may be used together with ABA as a functional trait that may, at least in part, help understand plant responses to recurrent seasonal stress in the current frame of global climate change.


Assuntos
Antocianinas , Ciclopentanos , Ecossistema , Oxilipinas , Estações do Ano , Clorofila , Folhas de Planta/fisiologia , Água
6.
Amino Acids ; 56(1): 27, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564019

RESUMO

We investigated the bioavailability of the calcium salt (HMB-Ca) and the free acid (HMB-FA) forms of ß-hydroxy-ß-methylbutyrate (HMB). Sixteen young individuals received the following treatments on three different occasions in a counterbalanced crossover fashion: (1) HMB-FA in clear capsules; (2) HMB-Ca in gelatine capsules; (3) HMB-Ca dissolved in water. All treatments provided 1 g of HMB. Blood samples were taken before and on multiple time points following ingestion. The following parameters were calculated: peak plasma (Cmax), time to peak (Tmax), slope of HMB appearance in blood, area under the curve (AUC), half-life time (t1/2) and relative bioavailability (HMB-Ca in water set as reference). All treatments led to rapid and large increases in plasma HMB. HMB-Ca in capsules and in water showed similar plasma HMB values across time (p = 0.438). HMB-FA resulted in lower concentrations vs. the other treatments (both p < 0.001). AUC (HMB-Ca in capsules: 50,078 ± 10,507; HMB-Ca in water: 47,871 ± 10,783; HMB-FA: 29,130 ± 12,946 µmol L-1 × 720 min), Cmax (HMB-Ca in capsules: 229.2 ± 65.9; HMB-Ca in water: 249.7 ± 49.7; HMB-FA: 139.1 ± 67.2 µmol L-1) and relative bioavailability (HMB-Ca in capsules: 104.8 ± 14.9%; HMB-FA: 61.5 ± 17.0%) were lower in HMB-FA vs. HMB-Ca (all p < 0.001). HMB-Ca in water resulted in the fastest Tmax (43 ± 22 min) compared to HMB-Ca in capsules (79 ± 40 min) and HMB-FA (78 ± 21 min) (all p < 0.05), while t1/2 was similar between treatments. To conclude, HMB-Ca exhibited superior bioavailability compared to HMB-FA, with HMB-Ca in water showing faster absorption. Elimination kinetics were similar across all forms, suggesting that the pharmaceutical form of HMB affects the absorption rates, but not its distribution or elimination.


Assuntos
Cálcio , Valeratos , Água , Humanos , Disponibilidade Biológica , Preparações Farmacêuticas
7.
Sci Rep ; 14(1): 7762, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565529

RESUMO

Groundwater is an excellent alternative to freshwater for drinking, irrigation, and developing arid regions. Agricultural, commercial, industrial, residential, and municipal activities may affect groundwater quantity and quality. Therefore, we aimed to use advanced methods/techniques to monitor the piezometric levels and collect groundwater samples to test their physicochemical and biological characteristics. Our results using software programs showed two main types of groundwater: the most prevalent was the Na-Cl type, which accounts for 94% of the groundwater samples, whereas the Mg-Cl type was found in 6% of samples only. In general, the hydraulic gradient values, ranging from medium to low, could be attributed to the slow movement of groundwater. Salinity distribution in groundwater maps varied between 238 and 1350 mg L-1. Although lower salinity values were observed in northwestern wells, higher values were recorded in southern ones. The collected seventeen water samples exhibited brackish characteristics and were subjected to microbial growth monitoring. Sample WD12 had the lowest total bacterial count (TBC) of 4.8 ± 0.9 colony forming unit (CFU mg L-1), while WD14 had the highest TBC (7.5 ± 0.5 CFU mg L-1). None of the tested water samples, however, contained pathogenic microorganisms. In conclusion, the current simulation models for groundwater drawdown of the Quaternary aquifer system predict a considerable drawdown of water levels over the next 10, 20, and 30 years with the continuous development of the region.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Água Subterrânea/química , Poços de Água , Água , Qualidade da Água , Poluentes Químicos da Água/análise
8.
Sci Rep ; 14(1): 7774, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565877

RESUMO

Human microbiota mainly resides on the skin and in the gut. Human gut microbiota can produce a variety of short chain fatty acids (SCFAs) that affect many physiological functions and most importantly modulate brain functions through the bidirectional gut-brain axis. Similarly, skin microorganisms also have identical metabolites of SCFAs reported to be involved in maintaining skin homeostasis. However, it remains unclear whether these SCFAs produced by skin bacteria can affect brain cognitive functions. In this study, we hypothesize that the brain's functional activities are associated with the skin bacterial population and examine the influence of local skin-bacterial growth on event-related potentials (ERPs) during an oddball task using EEG. Additionally, five machine learning (ML) methods were employed to discern the relationship between skin microbiota and cognitive functions. Twenty healthy subjects underwent three rounds of tests under different conditions-alcohol, glycerol, and water. Statistical tests confirmed a significant increase in bacterial population under water and glycerol conditions when compared to the alcohol condition. The metabolites of bacteria can turn phenol red from red-orange to yellow, confirming an increase in acidity. P3 amplitudes were significantly enhanced in response to only oddball stimulus at four channels (Fz, FCz, and Cz) and were observed after the removal of bacteria when compared with that under the water and glycerol manipulations. By using machine learning methods, we demonstrated that EEG features could be separated with a good accuracy (> 88%) after experimental manipulations. Our results suggest a relationship between skin microbiota and brain functions. We hope our findings motivate further study into the underlying mechanism. Ultimately, an understanding of the relationship between skin microbiota and brain functions can contribute to the treatment and intervention of diseases that link with this pathway.


Assuntos
Glicerol , Microbiota , Humanos , Encéfalo/metabolismo , Ácidos Graxos Voláteis/metabolismo , Cognição , Eletroencefalografia , Água
9.
BMC Public Health ; 24(1): 952, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566137

RESUMO

BACKGROUND: Urogenital schistosomiasis (UgS) remains a persistent health challenge among adolescents in Anambra State, Nigeria, despite ongoing control efforts. Mass praziquantel treatment programs, initiated in 2013, primarily target primary school-aged children (5-14 years old), leaving adolescents (10-19 years old) enrolled in secondary schools vulnerable to urogenital schistosomiaisis. Additionally, the extent of female genital schistosomiasis (FGS), a neglected gynaecological manifestation of UgS remains unclear. METHODOLOGY: To address these gaps, a cross-sectional study was conducted in Anaocha Local Government Area from February to May 2023. Four hundred and seventy consenting adolescents aged 10-19 years were enrolled. Urinalysis including urine filtration was employed to confirm haematuria and detect urogenital schistosomiasis (UGS) among the participants. For females with heavy infections (≥ 50 eggs/10 ml urine), a gynaecologist performed colposcopy examinations, complemented by acetic acid and Lugol's iodine staining to assess for female genital schistosomiasis (FGS) lesions or other related reproductive health conditions. Socio-demographic data, including information on potential risk factors, were systematically collected using the Kobo ToolBox software, following gender-sensitive data collection guidelines. Data were analysed using SPSS version 25, incorporating descriptive statistics, multinomial logistic regression, odds ratios, and significance testing. RESULTS: Among the 470 adolescents (52.8% females, 47.2% males) examined, an overall UgS prevalence of 14.5% was observed, with an average of 5.25 eggs per 10 ml of urine. Females had a slightly higher prevalence (16.1%), and 7.5% had heavy infections. Although gender differences in infection rates were not statistically significant, males had slightly higher odds of infection (OR: 1.332; 95% CI: 0.791-2.244; p-value: 0.280). Adolescents aged 10-14 had the highest prevalence, with significantly increased odds of infection (OR: 1.720; 95% CI: 1.012-2.923; p-value: 0.045). Colposcopy examinations of females with heavy infections revealed FGS lesions and co-infections with Trichomonas vaginalis. Haematuria, though prevalent (24.6%), was not the sole indicator, as those without it faced significantly higher odds of infection (OR: 2.924; 95% CI: 1.731-4.941; p-value: 0.000). Dysuria and genital itching/burning sensation were other UgS and FGS associated symptoms. Direct water contact was associated with higher infection odds (OR: 2.601; 95% CI: 1.007-6.716; p-value: 0.048). Various risk factors were associated with UgS. CONCLUSION: The study highlights the need for a comprehensive Urogenital Schistosomiasis (UGS) control strategy that includes secondary school adolescents, emphasizes risk factor management, promotes safe water practices, and raises awareness about UGS and Female Genital Schistosomiasis (FGS) among adolescents, thus improving control efforts and mitigating this health challenge in the region.


Assuntos
Esquistossomose Urinária , Masculino , Criança , Humanos , Feminino , Adolescente , Pré-Escolar , Adulto Jovem , Adulto , Animais , Esquistossomose Urinária/diagnóstico , Esquistossomose Urinária/epidemiologia , Estudos Transversais , Hematúria/epidemiologia , Nigéria/epidemiologia , Genitália Feminina , Prevalência , Água , Schistosoma haematobium
10.
Environ Monit Assess ; 196(5): 420, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570413

RESUMO

Monitoring and protecting freshwater habitats are paramount for a sustainable water management perspective. This study investigated potentially toxic elements (PTEs) in the potamic water of the Anday Stream Basin (Türkiye), Black Sea Region, for a hydrological year (from May 2020 to April 2021). Among PTEs, the highest average values were recorded for sodium (Na) at 41.3 mg/L and the lowest for mercury (Hg) at 0.009 µg/L and noted under quality guidelines. The stream was found to be at the level of "Low Heavy Metal Pollution" and "Low Contamination" based on the ecotoxicological risk indices. The highest calculated hazard quotient (HQ) value of 1.21E-02 for Cd was noted in the children via the dermal pathway and the lowest of 6.91E-06 for Fe in adults via the ingestion pathway. Results revealed a higher hazard index (HI) value of 1.50E-02 for Cd to children and the lowest of 1.98E-05 for Fe to adults. As a result of applying agricultural risk indices, the stream showed sodium adsorption ratio values less than 6 and was found to be "Excellent" for agriculture. However, the sodium percentage values were less than 20 and found "Permissible" and the magnesium hazard > 50 and noted as "Unsuitable" for agriculture. Statistical analysis revealed that natural factors mainly attributed to PTE contamination of the Anday Stream Basin.


Assuntos
Mercúrio , Metais Pesados , Criança , Adulto , Humanos , Monitoramento Ambiental/métodos , Água/análise , Rios , Mar Negro , Turquia , Metais Pesados/análise , Mercúrio/análise , Medição de Risco , Sódio/análise , Cádmio/análise
11.
Opt Express ; 32(7): 12141-12159, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571046

RESUMO

It is important to determine the relationship between the concentration of chlorophyll a (Chla) and the inherent optical properties (IOPs) of ocean water to develop optical models and algorithms that characterize the biogeochemical properties and estimate biological pumping and carbon flux in this environment. However, previous studies reported relatively large variations in the particulate backscattering coefficient (bbp(λ)) and Chla from more eutrophic high-latitude waters to clear oligotrophic waters, especially in oligotrophic oceanic areas where these two variables have little covariation. In this study, we examined the variability of bbp(λ) and Chla in the euphotic layer in oligotrophic areas of the tropical Western Pacific Ocean and determined the sources of these variations by reassessment of in-situ measurements and the biogeochemical-argo (BGC-Argo) database. Our findings identified covariation of bbp(λ) and Chla in the water column below the deep Chla maximum (DCM) layer, and indicated that there was no significant correlation relationship between bbp(λ) and Chla in the upper layer of the DCM. Particles smaller than 3.2 µm that were in the water column above the DCM layer had a large effect on the bbp(λ) in the vertical profile, but particles larger than 3.2 µm and smaller than 10 µm had the largest effect on the bbp(λ) in the water column below the DCM layer. The contribution of non-algal particles (NAPs) to backscattering is up to 50%, which occurs in the water depth of 50 m and not consistent with the distribution of Chla. Phytoplankton and NAPs were modeled as coated spheres and homogeneous spherical particles to simulate the bbp(λ) of the vertical profile by Aden-Kerker method and Mie theory, and the results also indicated that the backscattering caused by particles less than 20 µm were closer to the measured data when they were below and above the DCM layer, respectively. This relationship also reflects the bbp(λ) of particles in the upper water was significantly affected particle size, but bbp(λ) in the lower water was significantly affected by Chla concentration. This effect may have relationship with phytoplankton photoacclimation and the relationship of a phytoplankton biomass maximum with particle size distribution in the water column according to the previous relevant studies. These characteristics also had spatial and seasonal variations due to changes of Chla concentration at the surface and at different depths. There was mostly a linear relationship between Chla and bbp(700) during winter. During other seasons, the relationship between these two variables was better characterized by a power function (or a logarithmic function) in the lower layer of the DCM. The spatial and vertical relationships between the bbp(λ) and Chla and the corresponding variations in the types of particles described in this study provide parameters that can be used for accurate estimation of regional geochemical processes.


Assuntos
Clorofila , Água , Clorofila A , Oceano Pacífico , Oceanos e Mares , Biomassa , Fitoplâncton/química
12.
Environ Monit Assess ; 196(5): 425, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573498

RESUMO

The remediation of polluted soil and water stands as a paramount task in safeguarding environmental sustainability and ensuring a dependable water source. Biochar, celebrated for its capacity to enhance soil quality, stimulate plant growth, and adsorb a wide spectrum of contaminants, including organic and inorganic pollutants, within constructed wetlands, emerges as a promising solution. This review article is dedicated to examining the effects of biochar amendments on the efficiency of wastewater purification within constructed wetlands. This comprehensive review entails an extensive investigation of biochar's feedstock selection, production processes, characterization methods, and its application within constructed wetlands. It also encompasses an exploration of the design criteria necessary for the integration of biochar into constructed wetland systems. Moreover, a comprehensive analysis of recent research findings pertains to the role of biochar-based wetlands in the removal of both organic and inorganic pollutants. The principal objectives of this review are to provide novel and thorough perspectives on the conceptualization and implementation of biochar-based constructed wetlands for the treatment of organic and inorganic pollutants. Additionally, it seeks to identify potential directions for future research and application while addressing prevailing gaps in knowledge and limitations. Furthermore, the study delves into the potential limitations and risks associated with employing biochar in environmental remediation. Nevertheless, it is crucial to highlight that there is a significant paucity of data regarding the influence of biochar on the efficiency of wastewater treatment in constructed wetlands, with particular regard to its impact on the removal of both organic and inorganic pollutants.


Assuntos
Carvão Vegetal , Poluentes Ambientais , Áreas Alagadas , Monitoramento Ambiental , Biodegradação Ambiental , Solo , Água
13.
Ann Hum Biol ; 51(1): 2310724, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38594936

RESUMO

BACKGROUND: Pastoralists live in challenging environments, which may be accompanied by unique activity, energy, and water requirements. AIM: Few studies have examined whether the demands of pastoralism contribute to differences in total energy expenditure (TEE) and water turnover (WT) compared to other lifestyles. SUBJECTS AND METHODS: Accelerometer-derived physical activity, doubly labelled water-derived TEE and WT, and anthropometric data were collected for 34 semi-nomadic Daasanach adults from three northern Kenyan communities with different levels of pastoralist activity. Daasanach TEEs and WTs were compared to those of other small-scale and industrialised populations. RESULTS: When modelled as a function of fat-free-mass, fat-mass, age, and sex, TEE did not differ between Daasanach communities. Daasanach TEE (1564-4172 kcal/day) was not significantly correlated with activity and 91% of TEEs were within the range expected for individuals from comparison populations. Mean WT did not differ between Daasanach communities; Daasanach absolute (7.54 litres/day men; 7.46 litres/day women), mass-adjusted, and TEE-adjusted WT was higher than most populations worldwide. CONCLUSIONS: The similar mass-adjusted TEE of Daasanach and industrialised populations supports the hypothesis that habitual TEE is constrained, with physically demanding lifestyles necessitating trade-offs in energy allocation. Elevated WT in the absence of elevated TEE likely reflects a demanding active lifestyle in a hot, arid climate.


Assuntos
Metabolismo Energético , Água , Adulto , Masculino , Humanos , Feminino , Quênia , Exercício Físico , Antropometria
14.
An Acad Bras Cienc ; 96(1): e20231088, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597494

RESUMO

The thorough redox alteration of a lava flow is an undescribed feature in intraplate basaltic provinces. The Early Cretaceous (134.5 Ma) Paraná Province displays that alteration in the major Muralha Flow. This oxidized and reduced flow from the southern part of the province was studied with satellite images, field surveying, petrography, and published whole rock geochemistry. The 100 x 100 km flow from the Cuesta de Haedo presents two hydrothermal tiers - lower Tier 1 is gray to white, upper Tier 2 is red. Iron oxyhydroxides characterize Tier 2. Tier 1 contains clay minerals, zeolites, pyrite and calcite, and agate (possibly amethyst) geodes. In a first event, the upper Tier 2 was oxidized by hot water from the underlying Guarani Paleoaquifer. The high water/rock ratio decreased due to porosity clogging by precipitation of secondary minerals, and the fluid became reducing. Lowering of Eh and pH was caused by reaction of water with reducing particles (calcite, organic molecules) present in the paleoerg sandstones and with fresh rock surfaces. A lower Tier 1 was then formed during slow, hot water percolation. Reduction was interrupted below 30 °C (calcite formation). Large scale, similar alteration occurred in all studied oceanic ridges and only rarely in continental environments.


Assuntos
Carbonato de Cálcio , Minerais , Água/química , Oxirredução , Brasil
15.
Physiol Plant ; 176(2): e14282, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38591354

RESUMO

In nature, drought and salt stresses often occur simultaneously and affect plant growth at multiple levels. However, the mechanisms underlying plant responses to drought and salt stresses and their interactions are still not fully understood. We performed a meta-analysis to compare the effects of drought, salt, and combined stresses on plant physiological, biochemical, morphological and growth traits, analyze the different responses of C3 and C4 plants, as well as halophytes and non-halophytes, and identify the interactive effects on plants. There were numerous similarities in plant responses to drought, salt, and combined stresses. C4 plants had a more effective antioxidant defense system, and could better maintain above-ground growth. Halophytes could better maintain photosynthetic rate (Pn) and relative water content (RWC), and reduce growth as an adaptation strategy. The responses of most traits (Pn, RWC, chlorophyll content, soluble sugar content, H2O2 content, plant dry weight, etc.) to combined stress were less-than-additive, indicating cross-resistance rather than cross-sensitivity of plants to drought and salt stresses. These results are important to improve our understanding of drought and salt cross-resistance mechanisms and further induce resistance or screen-resistant varieties under stress combination.


Assuntos
Secas , Peróxido de Hidrogênio , Peróxido de Hidrogênio/farmacologia , Cloreto de Sódio/farmacologia , Plantas , Água , Estresse Salino , Estresse Fisiológico
16.
Environ Geochem Health ; 46(5): 160, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592564

RESUMO

As a notable toxic substance, metalloid arsenic (As) widely exists in water body and drinking As-contaminated water for an extended period of time can result in serious health concerns. Here, the performance of nanoscale zero-valent iron (nZVI) modified N-doped biochar (NBC) composites (nZVI@NBC) activated peroxydisulfate (PDS) for As(III) removal was investigated. The removal efficiencies of As(III) with initial concentration ranging from 50 to 1000 µg/L were above 99% (the residual total arsenic below 10 µg/L, satisfying the contaminant limit for arsenic in drinking water) within 10 min by nZVI@NBC (0.2 g/L)/PDS (100 µM). As(III) removal efficiency influenced by reaction time, PDS dosage, initial concentration, pH, co-existing ions, and natural organic matter in nZVI@NBC/PDS system were investigated. The nZVI@NBC composite is magnetic and could be conveniently collected from aqueous solutions. In practical applications, nZVI@NBC/PDS has more than 99% As(III) removal efficiency in various water bodies (such as deionized water, piped water, river water, and lake water) under optimized operation parameters. Radical quenching and EPR analysis revealed that SO4·- and ·OH play important roles in nZVI@NBC/PDS system, and the possible reaction mechanism was further proposed. These results suggest that nZVI@NBC activated peroxydisulfate may be an efficient and fast approach for the removal of water contaminated with As(III).


Assuntos
Arsênio , Metaloides , Água , Água Doce , Ferro
17.
Environ Monit Assess ; 196(5): 438, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592580

RESUMO

Advanced sensor technology, especially those that incorporate artificial intelligence (AI), has been recognized as increasingly important in various contemporary applications, including navigation, automation, water under imaging, environmental monitoring, and robotics. Data-driven decision-making and higher efficiency have enabled more excellent infrastructure thanks to integrating AI with sensors. The agricultural sector is one such area that has seen significant promise from this technology using the Internet of Things (IoT) capabilities. This paper describes an intelligent system for monitoring and analyzing agricultural environmental conditions, including weather, soil, and crop health, that uses internet-connected sensors and equipment. This work makes two significant contributions. It first makes it possible to use sensors linked to the IoT to accurately monitor the environment remotely. Gathering and analyzing data over time may give us valuable insights into daily fluctuations and long-term patterns. The second benefit of AI integration is the remote control; it provides for essential activities like irrigation, pest management, and disease detection. The technology can optimize water usage by tracking plant development and health and adjusting watering schedules accordingly. Intelligent Control Systems (Matlab/Simulink Ver. 2022b) use a hybrid controller that combines fuzzy logic with standard PID control to get high-efficiency performance from water pumps. In addition to monitoring crops, smart cameras allow farmers to make real-time adjustments based on soil moisture and plant needs. Potentially revolutionizing contemporary agriculture, this revolutionary approach might boost production, sustainability, and efficiency.


Assuntos
Inteligência Artificial , Internet das Coisas , Computação em Nuvem , Monitoramento Ambiental , Agricultura , Inteligência , Solo , Água , Abastecimento de Água
18.
Se Pu ; 42(4): 345-351, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38566423

RESUMO

A method based on ultra performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-MS/MS) was developed and validated for the rapid and accurate determination of adenosine (Ado) in cardiac tissues with high sensitivity and specificity. The samples were dissolved in 1 mL of ultrapure water containing 10 µmol/L 2-hydroxy-3-nonyladenine hydrochloride (EHNA) as a stabilizer, ground at low temperature for 2 min, and then ultrasonically extracted at 60 Hz in an ice-water bath for 40 min. Methanol and 5 mmol/L ammonium acetate solution were used as the mobile phases under a flow rate of 0.4 mL/min, a column temperature of 40 ℃ and an injection volume of 3 µL. The Ado in cardiac tissue was qualitatively and quantitatively analyzed by electrospray ionization (ESI) positive-ion-switching in multiple reaction monitoring (MRM) mode. A solvent standard curve and the external standard method were used for the accurate quantification of Ado. The results showed that the matrix effect of Ado in cardiac tissue was very low. A good linear relationship was obtained in the range of 0.1-160 ng/mL, and the correlation coefficient (r2) was 0.9930. The limits of detection (LOD) and quantification (LOQ) were 0.03 and 0.1 ng/mL, respectively. The spiked recoveries of Ado in murine cardiac tissue were 113.6%, 96.3%, and 102.9% at three spiked levels of low, medium, and high, respectively. The intra-day repeatability (RSDs) were 1.7%-8.4%, and the inter-day reproducibility (RSDs) were 2.6%-7.4%. Based on the correlation and consistency results, a positive bias was observed between the proposed UPLC-MS/MS method and the double-antibody sandwich method. Moreover, the Ado contents detected by these two methods were significantly positively correlated (P<0.0001). Cardiac tissue samples were collected from 17 mice and 17 rats and detected in our laboratory. The content ranges of Ado in the cardiac tissues of mice and rats determined by the developed UPLC-MS/MS method were 3.25-8.78 mg/kg and 10.24-15.19 mg/kg, respectively (average adenosine contents: 5.37 and 12.60 mg/kg, respectively). The developed method is simple, accurate, sensitive, and it is suitable for the determination of Ado in cardiac tissues. It also provides important technical support for cardiac clinical research and disease diagnosis.


Assuntos
Espectrometria de Massas em Tandem , Água , Camundongos , Animais , Ratos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Cromatografia Líquida de Alta Pressão , Reprodutibilidade dos Testes
19.
J Physiol Pharmacol ; 75(1)2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38583435

RESUMO

Endothelins and renal dopamine contribute to control of renal function and arterial pressure in health and various forms of experimental hypertension, the action is mediated by tonic activity of specific receptors. We determined the action mediated by endothelin type B and by dopamine D3 receptors (ETB-R, D3-R) in anaesthetized spontaneously hypertensive (SHR) and in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. In rats of both hypertension models infused during 60 min into the interstitium of in situ kidney were either ETB-R antagonist, BQ788 (0.67 mg kg-1 BW h-1) or D3-R antagonist, GR103691 (0.2 mg kg-1 BW h-1). Arterial pressure (MAP), renal artery blood flow (RBF, transonic probe) and renal medullary blood flow (MBF, laser-Doppler) were measured along with sodium, water and total solute excretion (UNaV, V, UosmV). Experiments with ETB-R blockade confirmed their tonic vasodilator action in the whole kidney (RBF) and medulla (MBF) in both hypertension models. In SHR only, the first evidence was provided that ETB-R specifically increases transtubular backflux of non-electrolyte solutes. In DOCA-salt rats ETB-R blockade caused an early decrease in water and salt transport whereas an increase was often reported from many previous studies. The most striking effect of D3-R blockade in SHR was a selective increase in MBF, which strongly suggested tonic vasoconstrictor action of these receptors in the renal medulla; this speaks against prevailing opinion that D3 receptors are virtually inactive in SHR. In our model variant of DOCA-salt rats of D3-R blockade clearly caused a rapid major increase in MAP in parallel with depression of renal haemodynamics.


Assuntos
Acetato de Desoxicorticosterona , Hipertensão , Ratos , Animais , Receptores de Dopamina D3 , Acetato de Desoxicorticosterona/farmacologia , Antagonistas dos Receptores de Endotelina/farmacologia , Ratos Endogâmicos SHR , Hipertensão/induzido quimicamente , Endotelinas/farmacologia , Água , Acetatos/farmacologia , Pressão Sanguínea , Endotelina-1
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