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1.
Lancet Planet Health ; 8 Suppl 1: S1, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38632904

RESUMEN

BACKGROUND: Affective processes play an important role in physical and mental health and in adaptation responses to the global environmental crisis. Eco-emotions-emotions that are substantially associated with the environment and anthropogenic changes happening within it-are complex and culturally varied. Despite the disproportionate impact of the global environmental crisis on low-income and middle-income countries, most psychological research to date has been conducted in high-income countries and has focused on climate change and negative climate emotions (eg, climate anxiety). The absence of diverse, globally representative evidence about emotions associated with the global environmental crisis beyond climate change hinders evidence-based action on psychological adaptation and the development of contextually and culturally appropriate coping strategies toward the wider range of negative anthropogenic effects. To account for this wider range of anthropogenic effects, we previously introduced an eco-emotions framework built on the planetary boundaries concept. We aimed to apply this framework to the current research on eco-emotional responses to identify remaining gaps that hinder evidence-based action. METHODS: We conducted a literature review of peer-reviewed studies assessing core affect (ie, emotional valence and arousal) and emotions with emphasis on study populations from low-income and middle-income countries and on the eight non-climate change planetary boundaries (biodiversity loss, freshwater use, ocean acidification, chemical pollution, air pollution, land system change, ozone depletion, and nitrogen and phosphorus perturbation). We searched Web of Science from database inception to Oct 31, 2023, for observational empirical studies of adults, using planetary boundary-specific (eg, freshwater use) or wider, newer, or overarching emotional concept (eg, solastalgia, environmental change) search terms. FINDINGS: In contrast to previous climate emotions work, our preliminary results of 135 peer reviewed studies identified a significant body of literature beyond climate change concerning emotional responses to the planetary boundaries of biodiversity loss, freshwater scarcity, and chemical pollution as well as emerging evidence of emotional responses to the other five planetary boundaries. INTERPRETATION: We found that the spectrum of eco-emotional responses ranged from being specific to a single planetary boundary to encompassing all planetary boundaries. Our findings underscore the importance of and urgent need for more holistic and diverse psychological intervention strategies targeting the wider range of anthropogenic effects during the rapidly intensifying global environmental crisis. FUNDING: Emmett Interdisciplinary Program in Environment and Resources; McGee and Levorsen Research Grant Program; and Center on Philanthropy and Civil Society at Stanford University.


Asunto(s)
Contaminación Ambiental , Agua de Mar , Adulto , Humanos , Concentración de Iones de Hidrógeno , Emociones , Biodiversidad
2.
Ying Yong Sheng Tai Xue Bao ; 35(3): 817-826, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38646770

RESUMEN

To explore the causes of red tides in Qinhuangdao coastal water, we conducted surveys on both water quality and red tides during April to September of 2022 and analyzed the relationships between main environmental factors and red tide organisms through the factor analysis and canonical correspondence analysis. The results showed that there were eight red tides along the coast of Qinhuangdao in 2022, with a cumulative blooming area of 716.1 km2. The red tides could be divided into three kinds based on the major blooming organisms and occurrence time, Noctiluca scintillans bloom, diatom-euglena (Skeletonema costatum, Eutreptiella gymnastica, Pseudo-nitzschia spp.) bloom, and dinoflagellate (Scrippsiella trochoidea and Ceratium furca) bloom. Seasonal factor played roles mainly during July to September, while inorganic nutrients including nitrogen and phosphorus influenced the blooms mainly in April and July. The canonical correspondence analysis suggested that N. scintillans preferred low temperature, and often bloomed with high concentrations of ammonium nitrogen and dissolved inorganic phosphorus. S. costatum, E. gymnastica, and Pseudo-nitzschia spp. could tolerate broad ranges of various environmental factors, but favored high temperature and nitrogen-rich seawater. C. furca and S. trochoidea had higher survival rate and competitiveness in phosphate-poor waters. Combined the results from both analyses, we concluded that the causes for the three kinds of red tide processes in Qinhuangdao coastal areas in 2022 were different. Adequate diet algae and appropriate water temperature were important factors triggering and maintaining the N. scintillans bloom. Suitable temperature, salinity and eutrophication were the main reasons for the diatom-euglena bloom. The abundant nutrients and seawater disturbance promoted the germination of S. trochoidea cysts, while phosphorus limitation caused the blooming organism switched to C. furca and maintained the bloom hereafter.


Asunto(s)
Diatomeas , Dinoflagelados , Monitoreo del Ambiente , Floraciones de Algas Nocivas , Agua de Mar , China , Dinoflagelados/crecimiento & desarrollo , Agua de Mar/análisis , Agua de Mar/química , Diatomeas/crecimiento & desarrollo , Océanos y Mares , Fósforo/análisis , Nitrógeno/análisis , Estaciones del Año
3.
Methods ; 226: 28-34, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38608850

RESUMEN

It is generally accepted that mineral deficiencies, including magnesium and calcium, are widespread globally. Dietary supplementation may be an effective approach to combat such deficiencies. However, challenges associated with limited mineral solubility in the digestive system can impede effective dissolution and hinder absorption, leading to deficiency, and undesirable gastrointestinal disturbances including diarrhoea. Seawater is considered to be a rich source of bioactive magnesium, calcium, and 72 other trace minerals. In this study, we examine two different marine-derived multimineral products as potential dietary supplements. Aquamin-Mg, sourced from seawater is rich in magnesium (12%), and Aquamin F, a seaweed-derived multimineral is rich in calcium (32%). Both products also contain a diverse array of over 72 minerals, characteristic of their oceanic origin. Our study comprises two experiments. The first experiment evaluates and compares the solubility of Aquamin-Mg, commercially available magnesium bisglycinate, and Pure Magnesium Bisglycinate (PrizMAG) during in vitro digestion using the INFOGEST method. Results demonstrate that Aquamin-Mg exhibits superior solubility than the other magnesium sources during the gastric and intestinal phases, particularly when administered alongside food materials. The second experiment is a randomized, double-blind, placebo-controlled study in a small cohort of healthy older aged adults to assess the tolerability of a combined Aquamin-Mg/Aquamin-F supplement over a 12-week period. The findings indicate that this combination supplement is well-tolerated, with no significant adverse events reported, emphasizing its potential as a means of addressing mineral deficiencies.


Asunto(s)
Calcio , Suplementos Dietéticos , Magnesio , Humanos , Magnesio/química , Suplementos Dietéticos/análisis , Calcio/química , Calcio/metabolismo , Femenino , Masculino , Anciano , Método Doble Ciego , Solubilidad , Agua de Mar/química , Digestión , Persona de Mediana Edad , Disponibilidad Biológica , Algas Marinas/química , Adulto , Minerales
4.
Mar Environ Res ; 196: 106441, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38484650

RESUMEN

Scyphozoan jellyfish, known for their evolutionary position and ecological significance, are thought to exhibit relatively notable resilience to ocean acidification. However, knowledge regarding the molecular mechanisms underlying the scyphozoan jellyfish response to acidified seawater conditions is currently lacking. In this study, two independent experiments were conducted to determine the physiological and molecular responses of moon jellyfish (Aurelia coerulea) polyps to within- and trans-generational exposure to two reduced pH treatments (pH 7.8 and pH 7.6). The results revealed that the asexual reproduction of A. coerulea polyps significantly declined under acute exposure to pH 7.6 compared with that of polyps at ambient pH conditions. Transcriptomics revealed a notable upregulation of genes involved in immunity and cytoskeleton components. In contrast, genes associated with metabolism were downregulated in response to reduced pH treatments after 6 weeks of within-generational acidified conditions. However, reduced pH treatments had no significant influence on the asexual reproduction of A. coerulea polyps after exposure to acidified conditions over a total of five generations, suggesting that A. coerulea polyps may acclimate to low pH levels. Transcriptomics revealed distinct gene expression profiles between within- and trans-generational exposure groups to two reduced pH treatments. The offspring polyps of A. coerulea subjected to trans-generational acidified conditions exhibited both upregulated and downregulated expression of genes associated with metabolism. These physiological and transcriptomic characteristics of A. coerulea polyps in response to elevated CO2 levels suggest that polyps produced asexually under acidified conditions may be resilient to such conditions in the future.


Asunto(s)
Cnidarios , Escifozoos , Animales , Agua de Mar , Transcriptoma , Concentración de Iones de Hidrógeno , Escifozoos/fisiología , Perfilación de la Expresión Génica
5.
Bioresour Technol ; 398: 130512, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38437960

RESUMEN

The reuse of wastewater after seawater cultivation is critically important. In this study, a phosphorus-supplemented seawater-wastewater cyclic system (PSSWCS) based on Chlorella pyrenoidosa SDEC-35 was developed. With the addition of phosphorus, the algal biomass and the ability to assimilate nitrogen and carbon were improved. At the nitrogen to phosphorus ratio of 20:1, the biomass productivity per mass of nitrogen reached 3.6 g g-1 (N) day-1 in the second cycle. After the third cycle the protein content reached 35.7% of dry mass, and the major metabolic substances in PSSWCS reached the highest content level of 89.5% (35.7% protein, 38.3% lipid, and 15.5% carbohydrate). After the fourth cycle the lipid content maintained at 40.1%. Furthermore, 100.0% recovery of wastewater in PSSWCS increased the nitrogen and carbon absorption to 15.0 and 396.8 g per tonne of seawater. This study achieved seawater-wastewater recycle and produced high-lipid and high-protein algae by phosphorus addition.


Asunto(s)
Chlorella , Microalgas , Aguas Residuales , Chlorella/metabolismo , Microalgas/metabolismo , Biomasa , Nitrógeno/metabolismo , Agua de Mar , Fósforo/metabolismo , Lípidos , Carbono/metabolismo
6.
Environ Toxicol Chem ; 43(5): 1012-1029, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38415986

RESUMEN

The use of novel high-throughput sequencing (HTS) technologies to examine the responses of natural multidomain microbial communities to scrubber effluent discharges to the marine environment is still limited. Thus, we applied metabarcoding sequencing targeting the planktonic unicellular eukaryotic and prokaryotic fraction (phytoplankton, bacterioplankton, and protozooplankton) in mesocosm experiments with natural microbial communities from a polluted and an unpolluted site. Furthermore, metagenomic analysis revealed changes in the taxonomic and functional dominance of multidomain marine microbial communities after scrubber effluent additions. The results indicated a clear shift in the microbial communities after such additions, which favored bacterial taxa with known oil and polycyclic aromatic hydrocarbons (PAHs) biodegradation capacities. These bacteria exhibited high connectedness with planktonic unicellular eukaryotes employing variable trophic strategies, suggesting that environmentally relevant bacteria can influence eukaryotic community structure. Furthermore, Clusters of Orthologous Genes associated with pathways of PAHs and monocyclic hydrocarbon degradation increased in numbers at treatments with high scrubber effluent additions acutely. These genes are known to express enzymes acting at various substrates including PAHs. These indications, in combination with the abrupt decrease in the most abundant PAHs in the scrubber effluent below the limit of detection-much faster than their known half-lives-could point toward a bacterioplankton-initiated rapid ultimate biodegradation of the most abundant toxic contaminants of the scrubber effluent. The implementation of HTS could be a valuable tool to develop multilevel biodiversity indicators of the scrubber effluent impacts on the marine environment, which could lead to improved impact assessment. Environ Toxicol Chem 2024;43:1012-1029. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Asunto(s)
Microbiota , Contaminantes Químicos del Agua , Microbiota/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Hidrocarburos Policíclicos Aromáticos , Bacterias/genética , Biodegradación Ambiental , Agua de Mar/microbiología , Petróleo , Plancton/genética
7.
Sci Total Environ ; 914: 169751, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38176548

RESUMEN

Considering the impact of the high salinity and high turbidity of coastal seawater on phosphorus forms, a new method was proposed to determine bioavailable inorganic phosphorus (BIP). The phosphorus most relevant to eutrophication is BIP, and traditional analysis methods may underestimate the degree of eutrophication. In this study, a microelectrode of multigold (AuµE) was fabricated for direct voltammetric determination of BIP without filtration, and BIP environmental characteristics including distribution and correlation relationships with environmental factors in typical coastal seawater of Northern China were analyzed. The proposed AuµE showed a low detection limit of 0.03 µM. The surface and bottom BIP concentrations ranged from 1.00 to 2.13 and from 0.88 to 2.05 µM, respectively. BIP dominated the total P (TP) accounting for 48.5-67.5 % in the surface layer samples, and 32.6-92.7 % in the bottom layer samples, respectively. The concentrations of BIP were obviously higher than those of DIP, indicating that DIP may underestimate the probability of eutrophication occurring. And BIP was positively correlated with dissolved oxygen (DO) (P < 0.05). BIP may be a promising indicator of eutrophication potential in coastal areas with high salinity and high turbidity. The proposed reliable voltammetry method provides a new indicator for environmental assessment and represents a significant step in the comprehensive analysis of P species.


Asunto(s)
Eutrofización , Agua de Mar , Agua de Mar/análisis , Fósforo/análisis , China , Salinidad , Monitoreo del Ambiente/métodos , Nitrógeno/análisis
8.
Chemosphere ; 350: 141049, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38182083

RESUMEN

From the available thermodynamic data in the literature, a review of the impact of the formation of complexes between triscarbonatoactinyl(VI) and alkaline earth(II) (Ae) is estimated under varying conditions. First, after analyzing the literature data and using the ascertained thermodynamic data available from the commissioned reviews from the Nuclear Energy Agency (Organization for the Economic Cooperation and Development) Thermochemical DataBank Project on actinides (An) U, Np, and Pu, and from recently determined AenUO2(CO3)3(4-2n)- thermodynamic functions, the formation of AenAnO2(CO3)3(4-2n)- complexes for Pu(VI) and Np(VI) are estimated using linear free energy relationships (LFERs). The data are in good agreement with the sole determination of AePuO2(CO3)32- from Jo et al. (Dalton Trans. 49, 11605), which gives a relative confidence in the LFERs, and allows the application to actual situations. From existing uranium data, first, the impact of the origin of the data on the calculated predominance is addressed under 0.1 M NaCl and atmospheric CO2(g); second, the influence of ionic strength and salinity on predominance is estimated; and finally, the influence of temperature up to 50 °C on the solubility of uraninite in a deep geological radioactive waste storage or disposal site is calculated. For neptunium and plutonium, the impact of the potential log10ß°(AenAnO2(CO3)3(4-2n)-) on Pourbaix diagrams of Pu and Np in Mg-Ca-CO3 media are estimated from Jo et al. (Dalton Trans. 49, 11605) and LFERs. Finally, the application to the speciation of Pu and Np in seawater is proposed.


Asunto(s)
Neptunio , Plutonio , Uranio , Uranio/química , Plutonio/química , Agua de Mar
9.
Mar Environ Res ; 195: 106369, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38262135

RESUMEN

Seawater temperature change is an important concern for seed production and pond culture of sea cucumbers. The present study found that tentacle activity frequency was significantly lower in sea cucumbers exposed to continuous and rapid temperature increases than that of those at ambient temperature. Feeding behavior directly determines food intake, and further affects physiology and growth efficiency of sea cucumbers. This means that the decline in feeding caused by continuous and rapid temperature increases needs to be addressed in sea cucumber aquaculture. However, a sudden temperature change of 5 °C had no significant effect on behaviors of sea cucumbers. This indicates that continuous temperature increases, rather than a sudden increase, result in behavioral impacts on sea cucumbers. Therefore, we recommend aqua-farmers reduce the feeding amount for sea cucumbers during continuous and rapid temperature increases. In the present study, feeding behavior was significantly higher in sea cucumbers fed with 3% dietary tryptophan than that of those fed with 0% and 5% dietary tryptophan. This indicates that 3% dietary tryptophan increases the food intake of sea cucumbers, and mitigates the feeding decline caused by continuous and rapid temperature increase. This indicates that tryptophan has the potential to promote the feeding of sea cucumbers in seed production and pond culture. Adhesion capacity of sea cucumbers fed with 5% dietary tryptophan was significantly higher than that of individuals fed with 0% and 3% dietary tryptophan. This suggests that dietary tryptophan increases the feeding of sea cucumbers exposed to continuous and rapid temperature increases in pond culture and seed production. In addition, this study found that sea cucumbers fed with 3% dietary tryptophan had higher intestinal colony richness under the continuously rapid temperature change. The present study provides an effective method to improve adhesion behavior and to alleviate the impacts on feeding behavior for seed production and pond culture of sea cucumbers exposed to continuous and rapid temperature increases.


Asunto(s)
Pepinos de Mar , Stichopus , Humanos , Animales , Stichopus/fisiología , Suplementos Dietéticos/análisis , Triptófano , Temperatura , Inmunidad Innata , Agua de Mar
10.
Chemosphere ; 351: 141191, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38218238

RESUMEN

Seawater reserves about 4.5 billion tons of uranium, if properly extracted, could be a sustainable green energy resource for hundreds of years, alternating its limited terrestrial ore and reducing the CO2 emitted from fossil fuels. The current seawater uranium adsorbents suffer neither economically viable nor adsorption efficiency, requiring more development to harvest satisfactorily uranium from seawater. Amidoxime-based fibrous adsorbents are the most promising adsorbents of seawater uranium due to abundant chelating sites. However, they suffer from severe shrinkage and stiffness once they dry, losing porous architecture and mechanical properties. Herein, an economical and scalable two-nozzle electrospinning technology was applied to produce poly amidoxime nanofibers (PAO NFs) supported by Poly acrylonitrile nanofibers (PAN NFs) as composite PAO/PAN nanofibrous mats with high structure stability. These PAO/PAN mats, with rapid wettability and excellent mechanical strength, show promising uranium adsorption capacities of 369.8 mg/g at seawater pH level, much higher than PAO and PAN NFs. The uranium adsorption capacity of the PAO/PAN mat reached 5.16 mg/g after 7 days of circulating (10 ppm uranium) spiked natural seawater. Importantly, the composite mat maintained its fibrous structure after five adsorption-desorption cycles with more than 80 % of its adsorption capacity, confirming its recyclability and stability. Therefore, the composite PAO/PAN mat fulfills the basic requirements for effectively and economically trapping uranium from seawater, which could be a matrix for further development.


Asunto(s)
Acrilonitrilo , Nanofibras , Oximas , Uranio , Uranio/química , Nanofibras/química , Agua de Mar/química , Adsorción
11.
J Environ Manage ; 353: 120196, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38290259

RESUMEN

The introduction of EPS recovered from waste sludge may have an impact on the process of microbial remediation of oil-contaminated seawater. This study investigated the effect of EPS on the self-remediation capacity of diesel-polluted seawater in Jiaozhou Bay. Hydrocarbon attenuation and microbial activity were monitored in seawater collected from five islands after diesel and N, P addition, with and without EPS, incubated under aerobic conditions. Compared to seawater without EPS, degradation of TPH (total petroleum hydrocarbon) doubled and improved degradation of non-volatile (C16-C24) hydrocarbons to some extent in EPS-added seawater. The introduction of EPS led to changes in microbiota richness and diversity, significantly stimulating the growth of Proteobacteria and Firmicutes phyla or Bacillus and Pseudomonas genera. RT-qPCR analysis indicated EPS caused higher increases in cytochrome P450 gene copies than alkB. Prediction of alkane decay genes from 16S rRNA sequencing data revealed that EPS addition obviously promoted genes related to ethanol dehydrogenation function in the microbial community. Additionally, EPS enhanced the enzymatic activities of alkane hydroxylase, ethanol dehydrogenase, phosphatase and lipase, but increased protease and catalase inconspicuously. The above outlook that environmental sustainability of EPS from waste sludge for diesel-contaminated seawater remediation may provide new perspectives for oil spill bioremediation.


Asunto(s)
Petróleo , Contaminantes del Suelo , Aguas del Alcantarillado , Matriz Extracelular de Sustancias Poliméricas/química , Matriz Extracelular de Sustancias Poliméricas/metabolismo , ARN Ribosómico 16S/genética , Bahías , Agua de Mar/química , Agua de Mar/microbiología , Biodegradación Ambiental , Hidrocarburos/análisis , Etanol/análisis , Petróleo/análisis , Microbiología del Suelo , Contaminantes del Suelo/análisis
12.
Ecotoxicol Environ Saf ; 271: 115981, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38242046

RESUMEN

To better understand the fate and assess the ingestible fraction of microplastics (by aquatic organisms), it is essential to quantify and characterize of their released from larger items under environmental realistic conditions. However, the current information on the fragmentation and size-based characteristics of released microplastics, for example from bio-based thermoplastics, is largely unknown. The goal of our work was to assess the fragmentation and release of microplastics, under ultraviolet (UV) radiation and in seawater, from polylactic acid (PLA) items, a bio-based polymer, and from polypropylene (PP) items, a petroleum-based polymer. To do so, we exposed pristine items of PLA and PP, immersed in filtered natural seawater, to accelerated UV radiation for 57 and 76 days, simulating 18 and 24 months of mean natural solar irradiance in Europe. Our results indicated that 76-day UV radiation induced the fragmentation of parent plastic items and the microplastics (50 - 5000 µm) formation from both PP and PLA items. The PP samples (48 ± 26 microplastics / cm2) released up to nine times more microplastics than PLA samples (5 ± 2 microplastics / cm2) after a 76-day UV exposure, implying that the PLA tested items had a lower fragmentation rate than PP. The particles' length of released microplastics was parameterized using a power law exponent (α), to assess their size distribution. The obtained α values were 3.04 ± 0.11 and 2.54 ± 0.06 (-) for 76-day UV weathered PP and PLA, respectively, meaning that PLA microplastics had a larger sized microplastics fraction than PP particles. With respect to their two-dimensional shape, PLA microplastics also had lower width-to-length ratio (0.51 ± 0.17) and greater fiber-shaped fractions (16%) than PP microplastics (0.57 ± 0.17% and 11%, respectively). Overall, the bio-based PLA items under study were more resistant to fragmentation and release of microplastics than the petroleum-based PP tested items, and the parameterized characteristics of released microplastics were polymer-dependent. Our work indicates that even though bio-based plastics may have a slower release of fragmented particles under UV radiation compared to conventional polymer types, they still have the potential to act as a source of microplastics in the marine environment, with particles being available to biota within ingestible size fractions, if not removed before major fragmentation processes.


Asunto(s)
Petróleo , Contaminantes Químicos del Agua , Polipropilenos , Microplásticos , Plásticos , Rayos Ultravioleta , Inmersión , Poliésteres , Agua de Mar , Polímeros , Contaminantes Químicos del Agua/análisis
13.
J Fish Dis ; 47(2): e13881, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37886898

RESUMEN

Cryptocaryoniasis remains a major parasitic disease and economic challenge for marine aquaculture. Cryptocaryoniasis in marine fish is caused by Cryptocaryon irritans (Ciliata). A theront is a motile, free-swimming stage in the life cycle of C. irritans, which is typically the infective stage that actively seeks out a host to initiate infection. Population density and growth rate of theronts were investigated in Nile tilapia, Oreochromis niloticus fed with citric acid-supplemented feed. The experiment involved feeding three diets with graded levels of citric acid (0, control diet, 0.5, 1 and 1.5 g kg-1 diet), to seawater-adapted Nile tilapia (O. niloticus) juveniles for 21 days. The results showed that citric acid in the fish feed had an impact on the theront number of C. irritans in a manner of dose-dependent. In the experimental cohort administered a diet supplemented with 1.5 g kg-1 citric acid, the population density of theronts was observed to be significantly reduced, measured at 29 ± 3.34, as opposed to 473.34 ± 16.48 in the control group at the culmination of the experiment. The observed population growth rate of theronts was significantly higher in the control group than in the group administered the citric acid feed (p < .005). The growth rate (r d-1 ) was 0.12 in control, 0.05 in 0.5 g kg-1 , 0.031 in 1 g kg-1 , and - 0.031 in 1.5 g kg-1 citric acid-supplemented groups. Fish growth and feed conversion ratio were not affected by the citric acid in the feed. In conclusion, the findings of this investigation provide a valuable addition to our understanding of the potential protective effects of citric acid supplementation for fish against the C. irritans parasite. This is evidenced by the observed reduction in theronts present in the water.


Asunto(s)
Cíclidos , Cilióforos , Enfermedades de los Peces , Gadiformes , Hymenostomatida , Tilapia , Humanos , Animales , Enfermedades de los Peces/prevención & control , Enfermedades de los Peces/parasitología , Dieta/veterinaria , Suplementos Dietéticos , Agua de Mar , Alimentación Animal/análisis
14.
Sci Total Environ ; 912: 168870, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38040377

RESUMEN

This work investigates the biodegradation of polyethylene (PE) and low-density polyethylene (LDPE) and the leaching of their harmful additives. Micro/macro-plastics of both types were subjected to different laboratory-controlled conditions for 3 months. Gas Chromatography-Mass Spectroscopy (GC-MS) results revealed that leachate concentrations ranged from 0.40 ± 0.07 µg/L to 96.36 ± 0.11 µg/L. It was concluded that the additives' leaching process was promoted by light. However, light was not the only factor examined; microorganisms, pH, salinity, aeration/mixing and temperature influenced the biodegradation process, too. GC-MS results showed a prodigious impact on the biodegradation process when Pseudomonas aeruginosa was added to the artificial seawater compared to plastics exposed to light/air only. Scanning Electron Microscopy (SEM) micrographs demonstrated a significant alteration in the plastics' morphologies. Similarly, Fourier-Transform Infrared Spectroscopy (FTIR) spectra showed obvious changes in plastics characteristic peaks, especially microplastics. Furthermore, it was shown that PE was more susceptible to degradation/biodegradation than LDPE. Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) findings showed that some toxic metals were present in water samples after experiments, with concentrations above the permissible limits. For instance, bio-augmentation/bio-stimulation experiments showed that the concentrations of Pb, Sr, and Zn were 0.59 mg/L, 70.09 mg/L, and 0.17 mg/L, respectively; values above the permissible limits. It is crucial to emphasise that plastics must be meticulously engineered to avoid environmental and human impacts, originated from their degradation by-products. Furthermore, a holistic approach engaging stakeholders, researchers, policymakers, industries and consumers, is essential to effectively tackle the global challenge of marine plastic pollution.


Asunto(s)
Plásticos , Polietileno , Humanos , Polietileno/metabolismo , Plásticos/química , Agua de Mar/química , Microscopía Electrónica de Rastreo , Biodegradación Ambiental
15.
Int J Biol Macromol ; 258(Pt 1): 128751, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38101661

RESUMEN

A novel polyvinyl alcohol-carbon nanotube containing an imidazolyl ionic liquid/chitosan composite hydrogel (termed CBCS) was prepared for highly selective uranium adsorption from seawater. The results show that CBCS has good adsorption properties for uranium within the pH range of 5.0-8.0. Kinetics and thermodynamics experiments show that the theoretical maximum adsorption capacity of CBCS to U(VI) is 496.049 mg/g (288 K, pH = 6.0), indicating a spontaneous exothermic reaction. Mechanism analysis shows that the hydroxyl group, amino group, and CN bond on the surface of CBCS directly participate in uranium adsorption and that the dense pores on the surface of CBCS play an important role in uranium adsorption. The competitive adsorption experiment shows that CBCS has excellent uranium adsorption selectivity. In addition, CBCS exhibits good reusability. After five adsorption-desorption cycles, the uranium adsorption rate of CBCS can still reach >98 %. Hence, CBCS has excellent potential for uranium extraction from seawater.


Asunto(s)
Quitosano , Líquidos Iónicos , Nanotubos de Carbono , Uranio , Alcohol Polivinílico , Uranio/química , Quitosano/química , Hidrogeles/química , Agua de Mar/química , Adsorción , Cinética , Concentración de Iones de Hidrógeno
16.
Mar Pollut Bull ; 199: 115919, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38134872

RESUMEN

Marine oil spills have devastating environmental impacts and extrapolation of experimental fate and impact data from the lab to the field remains challenging due to the lack of comparable field data. In this work we compared two field systems used to study in situ oil depletion with emphasis on biodegradation and associated microbial communities. The systems were based on (i) oil impregnated clay beads and (ii) hydrophobic Fluortex adsorbents coated with thin oil films. The bacterial communities associated with the two systems displayed similar compositions of dominant bacterial taxa. Initial abundances of Oceanospirillales were observed in both systems with later emergences of Flavobacteriales, Alteromonadales and Rhodobacterales. Depletion of oil compounds was significantly faster in the Fluortex system and most likely related to the greater bioavailability of oil compounds as compared to the clay bead system.


Asunto(s)
Gammaproteobacteria , Contaminación por Petróleo , Petróleo , Petróleo/metabolismo , Arcilla , Agua de Mar/química , Biodegradación Ambiental , Bacterias/metabolismo , Hidrocarburos/metabolismo
17.
Sci Total Environ ; 911: 168583, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-37981157

RESUMEN

Aeolian dust is an essential source of growth-limiting nutrients for marine phytoplankton. Despite being at the core of the Global Dust Belt, the response of the Arabian Gulf ecosystem to such atmospheric forcing is rarely documented. Here, the hydro-biological effect of mineral dust was studied in the northern Arabian Gulf (NAG) off Kuwait through monthly water sampling (December 2020 to December 2021), dust-storm follow-up sampling, and mineral dust and nutrient addition in-situ experiments. The multivariate analysis of oceanographic data revealed pronounced hydro-biological seasonality. The mineral dust deposition during two severe dust storm events in March and June 2021 showed a spatially varying effect of dust on coastal waters. The dust storms elevated the surface dissolved iron levels by several magnitudes, increased the dissolved inorganic nitrogen and phosphorous levels, changed their stoichiometry, and offset the hydrobiological seasonality. In the microcosms, dust input temporarily reduced phytoplankton phosphorous limitation in a dose-dependent manner when mesozooplankton (copepods) grazing was minimal. The microphytoplankton response to mineral dust inputs was comparable to that with nitrogen and phosphorous treatment. While Both treatments increased diatom size structure and biomass, the abundance of single-celled diatoms was comparatively higher in dust treatment. Multivariate analysis indicated that dust deposition alters the hydrographical properties of the surface ocean during dust storm events. The effects, though transient, were traceable for 3-16 days post-storm in coastal waters. The response of the summer phytoplankton to these changes, if delayed or muted, should be interpreted with caution given the summer water column stratification, the high nitrogen: phosphorous ratio and the low phosphorous solubility of aerosol dust, and the complex pelagic microbial food web interactions in the NAG. This study thus underlines the importance of a multivariate approach in documenting the ecological implications of Aeolian dust storms on marine environments closer to the dust source regions.


Asunto(s)
Diatomeas , Fitoplancton , Fitoplancton/fisiología , Ecosistema , Polvo/análisis , Diatomeas/fisiología , Fósforo , Agua , Minerales , Nitrógeno/análisis , Agua de Mar/química
18.
Environ Sci Technol ; 57(51): 21908-21916, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38085070

RESUMEN

Improving the adsorption selectivity, enhancing the extraction capacity, and ensuring the structural stability of the adsorbent are the key to realize the high efficiency recovery of uranium. In this work, we utilized the strong Lewis acid-base interaction between S2- and U(VI)O22+ coupling rapid electron transfer at the MnS/U(VI)O22+ solid-liquid interface to achieve excellent selectivity, high adsorption capacity, and rapid extraction of uranium. The as-synthesized MnS adsorbent exhibited an ultrahigh uranium extraction capacity (2457.05 mg g-1) and a rapid rate constant (K = 9.11 × 10-4 g h-1 mg-1) in seawater with 100.7 ppm of UO2(NO3)2 electrolyte. The kinetic simulation reveals that this adsorption process is a chemical adsorption process and conforms to a pseudo-second-order kinetic model, indicating electron transfer at the MnS/U(VI)O22+ solid-liquid interface. The relevant (quasi) in situ spectroscopic characterization and theoretical calculation results further revealed that the outstanding uranium extraction property of MnS could be attributed to the highly selective UO22+ adsorption of MnS with lower adsorption energy as a result of the strong interaction between S2- and UO22+ and the rapid mass transfer and interface electron transfer from S2- and low-valent Mn(II) to U(VI)O22+.


Asunto(s)
Uranio , Uranio/química , Electrones , Transporte de Electrón , Azufre , Adsorción , Agua de Mar
19.
Bull Environ Contam Toxicol ; 112(1): 21, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38150047

RESUMEN

Increased anthropogenic emissions of carbon dioxide (CO2) have resulted in ocean acidification (OA) that is intertwined with enhanced ocean stratification. Diatoms are assumed to suffer from a more nutrient-limited condition in the future ocean. This study aimed to explore how OA affects the diatom dynamics under nutrient-poor conditions and the ability of diatoms to perceive nutrients (nitrogen, phosphorus, silicon, and trace metals) and cadmium (Cd) stimuli and assimilate nitrogen when receiving nutrients or Cd supplementation. Our study observed that diatom population grown under OA condition declined faster than those grown under ambient condition. Ocean acidification greatly lower intracellular Ca2+ concentration in diatom cells. Intracellular Ca2+ burst was involved in phosphorus accumulation but not in nitrogen, silicon, essential metals, and cadmium uptake. Our data demonstrate slower NO3- assimilation rates of diatoms grown in acidified seawater. Our study also indicates that diatoms have a poor perception of phosphorus availability under OA condition.


Asunto(s)
Cadmio , Diatomeas , Cadmio/toxicidad , Concentración de Iones de Hidrógeno , Acidificación de los Océanos , Agua de Mar , Silicio , Nitrógeno , Nutrientes , Fósforo
20.
Int J Mol Sci ; 24(24)2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38139257

RESUMEN

Gastric ulcers are often exacerbated by factors such as nonsteroidal anti-inflammatory drugs (NSAIDs) and inflammation, and they have a substantial impact on a significant portion of the population. Notably, indomethacin is recognized as a prominent contributor to ulcers. This study investigated this potential method, with normalization to the anti-inflammatory and antiulcer properties of deep-sea water (DSW)-derived mineral water, using an indomethacin-induced gastric ulcer model in rats. The study involved four groups (n = 6 rats/group): normal control group (CON), indomethacin-only group (IND), indomethacin with trace mineral water group (TM), and indomethacin with high magnesium low sodium water group (HMLS). For three weeks, the CON and IND groups consumed tap water, while the TM and HMLS groups had access to mineral water. Gastric ulcers were induced on the final day using indomethacin, for all groups except the CON group. The results demonstrated that HMLS intake significantly improved gastric mucosal damage, preserved mucin stability, and increased gastric thickness, indicating its potential to prevent and alleviate indomethacin-induced gastric ulcers. Furthermore, HMLS consumption led to the upregulation of key genes associated with inflammation and a reduction in inflammatory cytokines. These findings suggest that DSW-derived mineral water, and particularly its high Mg2+ content, may offer promising health benefits including anti-inflammatory and anti-ulcer properties.


Asunto(s)
Antiulcerosos , Aguas Minerales , Úlcera Gástrica , Ratas , Animales , Indometacina/farmacología , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/prevención & control , Ratas Wistar , Antiulcerosos/farmacología , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios/efectos adversos , Mucosa Gástrica , Agua de Mar , Inflamación/tratamiento farmacológico
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