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1.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1474-1484, 2024 Mar.
Artículo en Chino | MEDLINE | ID: mdl-38621931

RESUMEN

As a common medicinal and edible resource in China, Coicis Semen has a long history of cultivation and medicinal use. Traditional Chinese medicine(TCM) clinically believes that Coicis Semen has the effect of strengthening the spleen and tonifying the lungs, clearing heat and dampness, removing pus and paralysis, and stopping diarrhea. Therefore, it is used to treat edema, foot odor, spleen deficiency, diarrhea, and other symptoms. The above effects are closely related to the active ingredients of Coicis Semen, such as esters, fatty acids, polysaccharides, proteins, as well as phenolic acids, sterols, flavonoids, lactams, triterpenes, alkaloids, and adenosine. Modern research has found that Coicis Semen also has anti-cancer, anti-inflammatory, antioxidant, hypoglycemic, and hypotensive effects and other pharmacological activities, and it can improve immunity and regulate lipid metabolism. Coicis Semen is widely distributed in China, mainly produced in Guizhou, Yunnan, Fujian, Sichuan, and other places, and the quality of Coicis Semen from different origins varies. From ancient times to the present, Coicis Semen processing methods have experienced the process from simple to complex, and the types of auxiliary materials are more extensive, such as soil, bran, and river sand. These processing methods have been inherited from generation to generation. Nowadays, the commonly used methods are bran-fried, stir-fried, sand-fried, etc. In this paper, by reviewing the relevant literature in China and abroad in recent years, the main active ingredients and related pharmacological effects of Coicis Semen are sorted out, and the effects of different origins and processing methods on the chemical composition of Coicis Semen are summarized, with a view to providing references for the comprehensive development and utilization of Coicis Semen and the further study of its mechanism of action.


Asunto(s)
Coix , Medicamentos Herbarios Chinos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Arena , China , Medicina Tradicional China , Diarrea
2.
Environ Monit Assess ; 196(5): 455, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625667

RESUMEN

This study is to understand the fate and ecological consequences of pyroxasulfone in aridisols of Punjab, a detailed dissipation study in soil, its influence on soil enzymes, microbial count and succeeding crops was evaluated. Half-lives (DT50) increased with an increase in the application rate of pyroxasulfone. Dissipation of pyroxasulfone decreased with increase in organic matter content of soil and was slower in clay loam soil (DT50 12.50 to 24.89) followed by sandy loam (DT50 8.91 to 17.78) and loamy sand soil (DT50 6.45 to 14.89). Faster dissipation was observed under submerged conditions (DT50 2.9 to 20.99 days) than under field capacity conditions (DT50 6.45 to 24.89 days). Dissipation increased with increase in temperature with DT50 varying from 6.46 to 24.88, 4.87 to 22.89 and 2.97 to 20.99 days at 25 ± 2, 35 ± 2 and 45 ± 2 °C, respectively. Dissipation was slower under sterile conditions and about 23.87- to 33.74-fold increase in DT50 was observed under sterile conditions as compared to non-sterile conditions. The application of pyroxasulfone showed short-lived transitory effect on dehydrogenase, alkaline phosphatase and soil microbial activity while herbicide has non-significant effect on soil urease activity. PCA suggested that dehydrogenase and bacteria were most sensitive among enzymatic and microbial activities. In efficacy study, pyroxasulfone effectively controlled Phalaris minor germination, with higher efficacy in loamy sand soil (GR50 2.46 µg mL-1) as compared to clay loam soil (GR50 5.19 µg mL-1).


Asunto(s)
Isoxazoles , Arena , Suelo , Sulfonas , Arcilla , Monitoreo del Ambiente , Oxidorreductasas
3.
Sci Rep ; 14(1): 8752, 2024 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627410

RESUMEN

The main challenge in the large-scale application of MICP lies in its low efficiency and promoting biofilm growth can effectively address this problem. In the present study, a prediction model was proposed using the response surface method. With the prediction model, optimum concentrations of nutrients in the medium can be obtained. Moreover, the optimized medium was compared with other media via bio-cementation tests. The results show that this prediction model was accurate and effective, and the predicted results were close to the measured results. By using the prediction model, the optimized culture media was determined (20.0 g/l yeast extract, 10.0 g/l polypeptone, 5.0 g/l ammonium sulfate, and 10.0 g/l NaCl). Furthermore, the optimized medium significantly promoted the growth of biofilm compared to other media. In the medium, the effect of polypeptone on biofilm growth was smaller than the effect of yeast extract and increasing the concentration of polypeptone was not beneficial in promoting biofilm growth. In addition, the sand column solidified with the optimized medium had the highest strength and the largest calcium carbonate contents. The prediction model represents a platform technology that leverages culture medium to impart novel sensing, adjustive, and responsive multifunctionality to structural materials in the civil engineering and material engineering fields.


Asunto(s)
Carbonato de Calcio , Cementación , Carbonato de Calcio/química , Arena , Precipitación Química
4.
PLoS One ; 19(4): e0298720, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38630661

RESUMEN

Geological evidence, such as tsunami deposits, is crucial for studying the largest rupture zone of the Kuril Trench in Hokkaido, Japan, due to its poor historical record. Although 17th-century tsunami deposits are widely distributed across Hokkaido, the presence of multiple wave sources during that period, including the collapse of Mt. Komagatake, complicates the correlation with their wave sources. Understanding the regional distribution of these tsunami deposits can provide valuable data to estimate the magnitude of megathrust earthquakes in the Kuril Trench. The northern part of Hidaka, Hokkaido, where tsunamis from multiple wave sources are expected to overlap, is distant from the Kuril Trench. To clarify the depositional history of tsunami deposits in such distal areas, evaluating the influence of the depositional environments on the event layer preservation becomes even more critical. We conducted field surveys in Kabari, located in the northern Hidaka region, identifying three sand layers from the 10th to the 17th century and two layers dating beyond 2.3 thousand years ago. The depositional ages of most sand layers potentially correlate with tsunami deposits resulting from the Kuril Trench earthquakes. Utilizing reconstructed paleo-sea level data, we estimated that most sand layers reached approximately 2 m in height. However, it is noteworthy that the latest sand layer from the 17th century exhibited an unusual distribution, more than 3 m in height. This suggests a different wave source as the Mt. Komagatake collapse. The discovery of multiple sand layers and their distributions is crucial to constraining the maximum magnitude of giant earthquakes in the Kuril Trench and understanding the volcanic tsunami events related to Mt. Komagatake.


Asunto(s)
Terremotos , Tsunamis , Japón , Arena , Geología
5.
Curr Microbiol ; 81(5): 129, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587647

RESUMEN

Arbuscular mycorrhizal (AM) fungi are being used as a new generation of biofertilizers to increase plant growth by improving plant nutrition and bio-protection. However, because of the obligatory nature of the plant host, large-scale multiplication of AM propagules is challenging, which limits its applicability. This study evaluates the ability of Burkholderia arboris to increase AM production in soybean mill waste and vermicompost amended by soil-sand mixture planted with sorghum as a host plant. The experiment was conducted in a nursery using a completely randomized design with four inoculation treatments (B. arboris, AM fungi, B. arboris + AM fungi, and control) under sterilized and unsterilized conditions. AM production was investigated microscopically (spore density and root colonization), and biochemically (AM-specific lipid biomarker, 16:1ω5cis derived from neutral lipid fatty acid (NLFA), and phospholipid fatty acid (PLFA) fractions from both soil and roots). Integrating B. arboris with AM fungi in organically amended pots was found to increase AM fungal production by 62.16 spores g-1 soil and root colonization by 80.85%. Biochemical parameters also increased with B. arboris inoculation: 5.49 nmol PLFA g-1 soil and 692.68 nmol PLFA g-1 root and 36.72 nmol NLFA g-1 soil and 3147.57 nmol NLFA g-1 root. Co-inoculation also increased glomalin-related soil protein and root biomass. Principal component analysis (PCA) further supported the higher contribution of B. arboris to AM fungi production under unsterilized conditions. In conclusion, inoculation of AM plant host seeds with B. arboris prior to sowing into organic potting mix could be a promising and cost-effective approach for increasing AM inoculum density for commercial production. Furthermore, efforts need to be made for up-scaling the AM production with different plant hosts and soil-substrate types.


Asunto(s)
Complejo Burkholderia cepacia , Burkholderia , Sorghum , Arena , Suelo , Soja , Grano Comestible , Ácidos Grasos , Hongos
6.
PLoS One ; 19(4): e0301296, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38574046

RESUMEN

In this study, the complex interactions between soil types, compaction, and moisture on nitrogen (N) transformation processes such as ammonia (NH3) volatilization, ammonification, nitrification, and denitrification were examined over a 30-day period using a simulated column approach. Two soil types: loam, and sandy loam, were subjected to three compaction treatments-control, surface, and sub-surface compaction-and two moisture regimes, dry and wet. Liquid urea ammonium nitrate (32-0-0) was used as the N fertilizer source at a rate of 200 kg N ha-1. Key indicators of N transformations were measured, including residual concentrations of ammonium (NH4-N) and nitrate (NO3-N), NO3-N leaching, NH3 volatilization, and nitrous oxide (N2O) emissions. Findings revealed that compaction significantly increased residual NH4-N concentrations in deeper soil profiles, with the highest 190.80 mg kg-1 recorded in loam soil under sub-surface compaction and dry conditions. Nitrification rates decreased across both soil types due to compaction, evidenced by elevated residual NH4-N levels. Increased NO3-N leaching was observed in loam soil (178.06 mg L-1), greater than sandy loam (81.11 mg L-1), due to initial higher residual NO3- in loam soil. The interaction of compaction and moisture most affected N2O emissions, with the highest emissions in control treatments during dry weather at 2.88 kg ha -1. Additionally, higher NH3 volatilization was noted in moist sandy loam soil under control conditions at 19.64 kg ha -1. These results highlight the necessity of considering soil texture, moisture, and compaction in implementing sustainable N management strategies in agriculture and suggest recommendations such as avoiding broadcast application in moist sandy loam and loam soil to mitigate NH3 volatilization and enhance N use efficiency, as well as advocating for readjustment of fertilizer rate based on organic matter content to reduce potential NO3-N leaching and N2O emissions, particularly in loam soil.


Asunto(s)
Nitrógeno , Suelo , Fertilizantes/análisis , Agricultura , Amoníaco/análisis , Arena , Óxido Nitroso/análisis
7.
Ying Yong Sheng Tai Xue Bao ; 35(3): 687-694, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38646756

RESUMEN

Understanding land structure change and stability in the process of oasisization is particularly important for the desertification control in sandy land. Based on land use data of eight periods from 1980 to 2020, we extracted the spatial distribution information of oasis land in Mu Us Sandy Land, and analyzed the spatio-temporal variations of land transformation patterns and stability of oasis land with overlay analysis and grid analysis. The results showed that desertification in the Mu Us Sandy Land had reversed, with a significant process of oasis. The area of forest and grassland increased from 10.2% in 1980 to 73.7% in 2020, while the area of oasisization land increased from 32500 km2 in 1980 to 33900 km2 in 2020. The area of extremely severe, severe, and moderate desertification significantly decreased, while the area of non-desertification and mild desertification obviously increased. The four patterns of oasisization land transformation, including stability, fluctuation, expansion, and retreat, which accounted for 78.7%, 12.2%, 6.2%, and 2.9% of the oasisization land area in 2020, respectively. The oasisization land with low change intensity (the cumulative change intensity less than 0.12) in the Mu Us Sandy Land accounted for 82.7% of the total oasisization area, and the oasisization land in the sandy land was generally stable. Zoning management strategies should be applied according to the stability of sand belt and transformation pattern of oasisization land to achieve the goal of efficient system management and improvement, including eliminating sand hazards at desertification expansion areas with strong wind and sand activities, consolidating sand resources at oasisization areas where ecologically fragile desertification was frequent, and sustainably managing and utilizing sand resources at stable expansion of oases in forest- and grass-rich oasisization areas.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , China , Árboles/crecimiento & desarrollo , Dióxido de Silicio , Bosques , Pradera , Arena , Poaceae/crecimiento & desarrollo
8.
Huan Jing Ke Xue ; 45(5): 2806-2816, 2024 May 08.
Artículo en Chino | MEDLINE | ID: mdl-38629543

RESUMEN

Net ecosystem productivity (NEP) is an important index for the quantitative evaluation of carbon sources and sinks in terrestrial ecosystems. Based on MOD17A3 and meteorological data, the vegetation NEP was estimated from 2000 to 2021 in the Loess Plateau (LP) and its six ecological subregions of the LP (loess sorghum gully subregions:A1, A2; loess hilly and gully subregions:B1, B2; sandy land and agricultural irrigation subregion:C; and earth-rock mountain and river valley plain subregion:D). Combined with the terrain, remote sensing, and human activity data, Theil-Sen Median trend analysis, correlation analysis, multiple regression residual analysis, and geographic detector were used, respectively, to explore the spatio-temporal characteristics of NEP and its response mechanism to climate, terrain, and human activity. The results showed that:① On the temporal scale, from 2000 to 2021 the annual mean NEP of the LP region (in terms of C) was 104.62 g·(m2·a)-1. The annual mean NEP for both the whole LP and each of the ecological subregions showed a significant increase trend, and the NEP of the LP increased by 6.10 g·(m2·a)-1 during the study period. The highest growth rate of the NEP was 9.04 g·(m2·a)-1, occurring in the A2 subregion of the loess sorghum gully subregions. The subregion C had the lowest growth rate of 2.74 g·(m2·a)-1. Except for the C subregion, all other ecological subregions (A1, A2, B1, B2, and D) were carbon sinks. ② On the spatial scale, the spatial distribution of annual NEP on the LP was significantly different, with the higher NEP distribution in the southeast of the LP and the lower in the northwest of the LP. The high carbon sink area was mainly distributed in the southern part of the loess sorghum gully subregions, and the carbon source area was mainly distributed in the northern part of the loess sorghum gully subregions and most of the C subregion. The high growth rate was mainly distributed in the central and the southern part of the A2 subregion and the southwest part of the B2 subregion. ③ Human activities had the greatest influence on the temporal variation in NEP in the LP and all the ecological subregions, with the correlation coefficient between human activity data and NEP being above 0.80, and the relative contribution rates of human factors was greater than 50%. The spatial distribution was greatly affected by meteorological factors, among which the precipitation and solar radiation were the main factors affecting the spatial changes in the NEP of the LP. The temporal and spatial variations in the NEP in the LP were influenced by natural and human social factors. To some extent, these results can provide a reference for the terrestrial ecosystem in the LP to reduce emissions and increase sinks and to achieve the goal of double carbon.


Asunto(s)
Clima , Ecosistema , Humanos , Tecnología de Sensores Remotos , Arena , Carbono/análisis , China , Cambio Climático
9.
Huan Jing Ke Xue ; 45(5): 3016-3026, 2024 May 08.
Artículo en Chino | MEDLINE | ID: mdl-38629562

RESUMEN

Sweet sorghum has a large biomass and strong cadmium (Cd) absorption capacity, which has the potential for phytoremediation of Cd-contaminated soil. In order to study the Cd phytoremediation effect of sweet sorghum assisted with citric acid on the typical parent materials in southern China, a field experiment was carried out in two typical parent material farmland areas (neutral purple mud field and jute sand mud field) with Cd pollution in Hunan Province. The results showed that:① Citric acid had no inhibitory effect on the growth of sweet sorghum. After the application of citric acid, the aboveground biomass of sweet sorghum at the maturity stage increased by 10.1%-24.7%. ② Both sweet sorghum planting and citric acid application reduced the soil pH value, and the application of citric acid further reduced the soil pH value at each growth stage of sweet sorghum; this decrease was greater in the neutral purple mud field, which decreased by 0.24-0.72 units. ③ Both sweet sorghum planting and citric acid application reduced the total amount of soil Cd, and the decreases in the neutral purple mud field and jute sand mud field were 23.8%-52.2% and 17.1%-31.8%, respectively. The acid-extractable percentage of soil Cd in both places increased by 38.6%-147.7% and 4.8%-22.7%, respectively. ④ The application of citric acid could significantly increase the Cd content in various tissues of sweet sorghum. The Cd content in the aboveground part of the plant in the neutral purple mud field was higher than that in the jute sand mud field, and the Cd content in stems and leaves was 0.25-1.90 mg·kg-1 and 0.21-0.64 mg·kg-1, respectively. ⑤ After applying citric acid, the Cd extraction amount of sweet sorghum in neutral purple mud soil in the mature stage reached 47.56 g·hm-2. In summary, citric acid could enhance the efficiency of sweet sorghum in the phytoremediation of Cd-contaminated soil, and the effect was better in neutral purple mud fields. This technology has the potential for remediation coupled with agro-production for heavy metal-contaminated farmland.


Asunto(s)
Contaminantes del Suelo , Sorghum , Cadmio/análisis , Biodegradación Ambiental , Suelo , Arena , Ácido Cítrico , Contaminantes del Suelo/análisis , China , Grano Comestible/química
10.
J Environ Radioact ; 275: 107430, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38615506

RESUMEN

Clay colloids in the subsurface environment have a strong adsorption capacity for radionuclides, and the mobile colloids will carry the nuclides for migration, which would promote the movability of radionuclides in the groundwater environment and pose a threat to the ecosphere. The investigations of the adsorption/desorption behaviors of radionuclides in colloids and porous media are significant for the evaluation of the geological disposal of radioactive wastes. To illustrate the adsorption/desorption behaviors of 241Am(Ⅲ) in Na-montmorillonite colloid and/or quartz sand systems at different pH (5, 7 and 9), ionic strengths (0, 0.1 and 5 mM), colloid concentrations (300 and 900 mg/L), nuclide concentrations (500, 800, 1100 and 1400 Bq/mL) and grain sizes (40 and 60 mesh), a series of batch sorption-desorption experiments were conducted. Combining the analysis of the physical and chemical properties of Na-montmorillonite with the Freundlich model, the influencing mechanism of different controlling factors is discussed. The experimental results show that the adsorption/desorption behaviors of 241Am(Ⅲ) in Na-montmorillonite colloid and/or quartz sand strongly are influenced by the pH value and ionic strength of a solution, the colloid concentration as well as quartz sand grain size. The adsorption and desorption isotherms within all the experimental conditions could be well-fitted by the Freundlich model and the correlation coefficients (R2) are bigger than 0.9. With the increase in pH, the adsorption partition coefficient (Kd) at 241Am(Ⅲ)-Na-montmorillonite colloid two-phase system and 241Am(Ⅲ)-Na-montmorillonite colloid-quartz sand three-phase system presents a trend which increases firstly followed by decreasing, due to the changes in the morphology of Am with pH. The Kd of 241Am(Ⅲ) adsorption on montmorillonite colloid and quartz sand decreases with increasing in ionic strength, which is mainly attributed to the competitive adsorption, surface complexation and the reduction of surface zeta potential. Additionally, the Kd increases with increasing colloid concentrations because of the increase in adsorption sites. When the mean grain diameter changes from 0.45 to 0.3 mm, the adsorption variation trends of 241Am(Ⅲ) remain basically unchanged. The research results obtained in this work are meaningful and helpful in understanding the migration behaviors of radionuclides in the underground environment.


Asunto(s)
Americio , Bentonita , Coloides , Cuarzo , Bentonita/química , Concentración Osmolar , Adsorción , Concentración de Iones de Hidrógeno , Coloides/química , Cuarzo/química , Americio/química , Americio/análisis , Contaminantes Radiactivos del Agua/química , Contaminantes Radiactivos del Agua/análisis , Contaminantes Radiactivos del Suelo/análisis , Contaminantes Radiactivos del Suelo/química , Modelos Químicos , Tamaño de la Partícula , Arena/química
11.
PeerJ ; 12: e17207, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38618566

RESUMEN

Long-term microplastics (MPs) environmental pollution trends cannot be understood only by investigating their presence on beaches. Without estimating MPs for the entire beach, comparisons between multiple beaches cannot be made. In this study, Nagasaki Prefecture was selected as the study site, we measured MPs accumulation rate to express the MPs pollution trend and weighted the measurement results to enable comparison of MPs content among multiple sandy beaches. The MPs accumulation rate in the study site was measured by periodic investigation at fixed spots. The average in the supratidal zone was 1.5 ± 0.9 mg-MPs/(m2-sand⋅ d) (n = 15). The weighting of the MPs content in hot spots and non-hot spots by their respective areas enabled us to obtain the representative value and the dispersion of the MPs content in the entire study site. The MPs contents in the three beaches were 298 ± 144, 1,115 ± 518, and 4,084 ± 2,243 mg-MPs/(m2-sand), respectively. Using these values, it is possible to compare the MPs contents of multiple beaches.


Asunto(s)
Dermatitis , Microplásticos , Humanos , Plásticos , Contaminación Ambiental , Arena
12.
PLoS One ; 19(4): e0300622, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38603682

RESUMEN

Breast cancer is one of the most often diagnosed cancers in women, and identifying breast cancer histological images is an essential challenge in automated pathology analysis. According to research, the global BrC is around 12% of all cancer cases. Furthermore, around 25% of women suffer from BrC. Consequently, the prediction of BrC depends critically on the quick and precise processing of imaging data. The primary reason deep learning models are used in breast cancer detection is that they can produce findings more quickly and accurately than current machine learning-based techniques. Using a BreakHis dataset, we demonstrated in this work the viability of automatically identifying and classifying BrC. The first stage is pre-processing, which employs an Adaptive Switching Modified Decision Based Unsymmetrical Trimmed Median Filter (ASMDBUTMF) to remove high-density noise. After the image has been pre-processed, it is segmented using the Thresholding Level set approach. Next, we propose a hybrid chaotic sand cat optimization technique, together with the Remora Optimization Algorithm (ROA) for feature selection. The suggested strategy facilitates the acquisition of precise functionality attributes, hence simplifying the detection procedure. Additionally, it aids in resolving problems pertaining to global optimization. Following the selection, the best characteristics proceed to the categorization procedure. A DL classifier called the Conditional Variation Autoencoder is used to discriminate between cancerous and benign tumors while categorizing them. Consequently, a classification accuracy of 99.4%, Precision of 99.2%, Recall of 99.1%, F- score of 99%, Specificity of 99.14%, FDR of 0.54, FNR of 0.001, FPR of 0.002, MCC of 0.98 and NPV of 0.99 were obtained using the proposed approach. Furthermore, compared to other research using the current BreakHis dataset, the results of our research are more desirable.


Asunto(s)
Neoplasias de la Mama , Felis , Perciformes , Femenino , Humanos , Animales , Neoplasias de la Mama/diagnóstico por imagen , Arena , Mama , Peces , Algoritmos
13.
Environ Geochem Health ; 46(5): 153, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587707

RESUMEN

The environmental fate and risks of ciprofloxacin (CIP) in the subsurface have raised intensive concerns. Herein, the transport behaviors of CIP in both saturated quartz sand and sand/multi-walled carbon nanotubes (MWCNTs) mixtures under different solution ionic strength of the solution and coexisting cation types were investigated. Batch adsorption experiments highlighted growing adsorptive capacity for CIP with the increasing content of MWCNTs in the MWCNTs-quartz sand mixtures (from 0.5% to 1.5%, w/w). Breakthrough curves (BTCs) of CIP in the MWCNTs-quartz sand mixtures were well fitted by the two-site chemical nonequilibrium model (R2 > 0.833). The estimated retardation factors for CIP increased from 9.68 to 282 with growing content of MWCNTs in the sand column, suggesting the presence of MWCNTs significantly inhibited the transport of CIP in saturated porous media. Moreover, the values of retardation factors are negatively correlated with the ionic strength and higher ionic strength could facilitate the transport of CIP in the saturated porous media. Compared with monovalent cations (Na+), the presence of divalent cations (Ca2+) significantly facilitated the transport of CIP in the columns due to the complexation between CIP and Ca2+ as well as deposition of MWCNTs aggregates on the sand surface. Results regarding CIP retention in columns indicated that MWCNTs could enhance the accumulation of CIP in the layers close to the influent of sand columns, while they could hinder upward transport of CIP to the effluent. This study improves our understanding for transport behaviors and environmental risk assessments of CIP in the saturated porous media with MWCNTs.


Asunto(s)
Nanotubos de Carbono , Porosidad , Cuarzo , Arena , Cationes , Ciprofloxacina , Concentración Osmolar
14.
PeerJ ; 12: e17165, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38590706

RESUMEN

Background: Plastic waste is a global environmental issue that impacts the well-being of humans, animals, plants, and microorganisms. Microplastic contamination has been previously reported at Kung Wiman Beach, located in Chanthaburi province along with the Eastern Gulf of Thailand. Our research aimed to study the microbial population of the sand and plastisphere and isolate microorganisms with potential plastic degradation activity. Methods: Plastic and sand samples were collected from Kung Wiman Beach for microbial isolation on agar plates. The plastic samples were identified by Fourier-transform infrared spectroscopy. Plastic degradation properties were evaluated by observing the halo zone on mineral salts medium (MSM) supplemented with emulsified plastics, including polystyrene (PS), polylactic acid (PLA), polyvinyl chloride (PVC), and bis (2-hydroxyethyl) terephthalate (BHET). Bacteria and fungi were identified by analyzing nucleotide sequence analysis of the 16S rRNA and internal transcribed spacer (ITS) regions, respectively. 16S and ITS microbiomes analysis was conducted on the total DNA extracted from each sample to assess the microbial communities. Results: Of 16 plastic samples, five were identified as polypropylene (PP), four as polystyrene (PS), four as polyethylene terephthalate (PET), two as high-density polyethylene (HDPE), and one sample remained unidentified. Only 27 bacterial and 38 fungal isolates were found to have the ability to degrade PLA or BHET on MSM agar. However, none showed degradation capabilities for PS or PVC on MSM agar. Notably, Planococcus sp. PP5 showed the highest hydrolysis capacity of 1.64 ± 0.12. The 16S rRNA analysis revealed 13 bacterial genera, with seven showing plastic degradation abilities: Salipiger, Planococcus, Psychrobacter, Shewanella, Jonesia, Bacillus, and Kocuria. This study reports, for the first time of the BHET-degrading properties of the genera Planococcus and Jonesia. Additionally, The ITS analysis identified nine fungal genera, five of which demonstrated plastic degradation abilities: Aspergillus, Penicillium, Peacilomyces, Absidia, and Cochliobolus. Microbial community composition analysis and linear discriminant analysis effect size revealed certain dominant microbial groups in the plastic and sand samples that were absent under culture-dependent conditions. Furthermore, 16S and ITS amplicon microbiome analysis revealed microbial groups were significantly different in the plastic and sand samples collected. Conclusions: We reported on the microbial communities found on the plastisphere at Kung Wiman Beach and isolated and identified microbes with the capacity to degrade PLA and BHET.


Asunto(s)
Actinomycetales , Microbiota , Actinomycetales/genética , Agar/metabolismo , Bacterias/genética , Microbiota/genética , Plásticos/metabolismo , Poliésteres/metabolismo , Poliestirenos/metabolismo , ARN Ribosómico 16S/genética , Arena
15.
Curr Microbiol ; 81(6): 138, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609554

RESUMEN

A Gram-stain-negative bacterium with a rod-to-ovoid shape, named strain M216T, was isolated from sand sediment from the coastal intertidal zone of Huludao, Liaoning Province, China. Growth was observed at 8-40 °C (optimal, 30 °C), pH 5.5-9.5 (optimal, pH 6.5) and 0.5-14.0% (w/v) NaCl (optimal, 6%). Strain M216T possessed ubiquinone-9 as its sole respiratory quinone and phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, one unidentified aminophosphoglycolipid, one unidentified aminophospholipid, two unidentified phosphoglycolipids, three unidentified phospholipids and three unidentified glycolipids as the main polar lipids. C12:0, C16:0, C12:0 3-OH, C16:1 ω9c, C18:1 ω9c and summed features 3 (C16:1 ω7c and/or C16:1 ω6c) were the major fatty acids (> 5%). The 16S rRNA gene sequence of strain M216T exhibited high similarity to those of 'Marinobacter arenosus' CAU 1620T and Marinobacter adhaerens HP15T (99.3% and 98.5%, respectively) and less than 98.5% similarity to those of the other type strains. The ANI and dDDH values between the strain M216T and 'Marinobacter arenosus' CAU 1620T were 87.4% and 33.3%, respectively; these values were the highest among the other type strains but lower than the species threshold. The G+C content of strain M216T was 58.3%. Genomic analysis revealed that strain M216T harbors the major CAZymes of GH13, GH23, GH73, and PL5, which are responsible for polysaccharide degradation and the potential ability to reduce nitrate to ammonia. Through phenotypic, genotypic, and chemotaxonomic analyses, we proposed the name Marinobacter albus sp. nov., a novel species in the genus Marinobacter, with its type strain M216T (= MCCC 1K08600T = KCTC 82894T).


Asunto(s)
Marinobacter , Marinobacter/genética , ARN Ribosómico 16S/genética , Arena , Amoníaco , China
16.
Sci Rep ; 14(1): 5125, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429361

RESUMEN

Alien woody species are successful invaders, frequently used for afforestation in regions like semi-arid lands. Shrubs and trees create important microhabitats in arid areas. Understorey vegetation in these habitats has unique species composition and coexistence. However, the impact of solitary woody species on understorey vegetation is less understood. This study evaluated the effect of native (Juniperus communis) and invasive solitary conifers (Pinus nigra) on surrounding vegetation, where individuals were relatively isolated (referred to as solitary conifers). The field study conducted in Pannonic dry sand grassland in 2018 recorded plant and lichen species presence around six selected solitary conifers. Composition and pattern of understorey vegetation were assessed using 26 m belt transects with 520 units of 5 cm × 5 cm contiguous microquadrats. Compositional diversity (CD) and the number of realized species combinations (NRC) were calculated from the circular transects. Results showed native conifer J. communis created more complex, organized microhabitats compared to alien P. nigra. CD and NRC values were significantly higher under native conifers than invasive ones (p = 0.045 and p = 0.026, respectively). Native species also had more species with a homogeneous pattern than the alien species. Alien conifers negatively affected understorey vegetation composition and pattern: some species exhibited significant gaps and clusters of occurrences along the transects under P. nigra. Based on our study, the removal of invasive woody species is necessary to sustain habitat diversity.


Asunto(s)
Pinus , Tracheophyta , Humanos , Arena , Pradera , Ecosistema , Plantas , Especies Introducidas
17.
Huan Jing Ke Xue ; 45(3): 1665-1673, 2024 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-38471878

RESUMEN

Changes in soil nitrogen components in tea gardens affect the soil nitrogen supply capacity and nitrogen cycle. In this study, soil samples were collected from forest land, cultivated land, and tea gardens with different plantation ages (30, 50, and 70 years) to explore the changes in soil nitrogen components and their relationship with physicochemical properties and enzyme activities. The results showed that:① with the increase in tea plantation age, the silt, total phosphorus, and urease and catalase activities gradually increased, whereas the sand, clay, pH, electrical conductivity, soil organic carbon, and the activities of invertase gradually decreased. The alkaline phosphatase activity increased first and then decreased with the increase in tea plantation age, and no significant differences were observed in soil water content and acid phosphatase activity. ② With the increase in tea plantation age, the contents of acid ammonia nitrogen, amino acid nitrogen, and nitrate nitrogen (NO3--N) increased significantly, and the contents of total nitrogen, acid ammonia nitrogen, hydrolyzable unknown nitrogen, and non-hydrolyzable nitrogen in tea gardens were significantly higher than those in forest land. ③ The total phosphorus, alkaline phosphatase, and urease were the main factors affecting soil nitrogen components. Among them, organic nitrogen components were significantly correlated with total phosphorus and alkaline phosphatase, and inorganic nitrogen components were significantly correlated with alkaline phosphatase, whereas total nitrogen had significant correlations with sand, silt, total phosphorus, urease, and alkaline phosphatase.


Asunto(s)
Fosfatasa Alcalina , Suelo , Suelo/química , Arena , Nitrógeno/análisis , Carbono , Ureasa , Amoníaco , Fósforo/análisis , , Microbiología del Suelo , China
18.
Appl Environ Microbiol ; 90(4): e0225323, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38440988

RESUMEN

We evaluated a unique model in which four full-scale wastewater treatment plants (WWTPs) with the same treatment schematic and fed with similar influent wastewater were tracked over an 8-month period to determine whether the community assembly would differ in the activated sludge (AS) and sand filtration (SF) stages. For each WWTP, AS and SF achieved an average of 1-log10 (90%) and <0.02-log10 (5%) reduction of total cells, respectively. Despite the removal of cells, both AS and SF had a higher alpha and beta diversity compared to the influent microbial community. Using the Sloan neutral model, it was observed that AS and SF were individually dominated by different assembly processes. Specifically, microorganisms from influent to AS were predominantly determined by the selective niche process for all WWTPs, while the microbial community in the SF was relatively favored by a stochastic, random migration process, except two WWTPs. AS also contributed more to the final effluent microbial community compared with the SF. Given that each WWTP operates the AS independently and that there is a niche selection process driven mainly by the chemical oxygen demand concentration, operational taxonomic units unique to each of the WWTPs were also identified. The findings from this study indicate that each WWTP has its distinct microbial signature and could be used for source-tracking purposes.IMPORTANCEThis study provided a novel concept that microorganisms follow a niche assembly in the activated sludge (AS) tank and that the AS contributed more than the sand filtration process toward the final microbial signature that is unique to each treatment plant. This observation highlights the importance of understanding the microbial community selected by the AS stage, which could contribute toward source-tracking the effluent from different wastewater treatment plants.


Asunto(s)
Aguas del Alcantarillado , Purificación del Agua , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos , Arena , Ríos , Aguas Residuales
19.
Chemosphere ; 355: 141758, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38518922

RESUMEN

The unsaturated behavior of permeable reactive barriers (PRB) is a critical component in predicting the removal efficiency through the adsorption of contaminants. This study investigates the framework to estimate the soil water characteristic curve (SWCC) and hydraulic conductivity function (HCF) for iron oxide-coated sand (IOCS) and zeolite, which are common materials used in PRBs. A multistep outflow (MSO) experiment was performed and the results of the MSO experiment were used to optimize associated parameters in Kosugi's SWCC and HCF. In addition, three scenarios of optimization analysis were investigated to evaluate the best-fitting model for estimating SWCC and HCF. The low root mean square error (RMSE) of fitted parameters indicates the Kosugi model well described the observed suction profiles in MSO experiments. In addition, the lowest RMSE and coefficient of variation suggested the inclusion of the additional parameter ß provided the best estimation of the three materials (clean sand, IOCS, and zeolite). The physically reasonable estimation of SWCC and HCF of the three materials from the optimized parameters suggests the proposed framework is a reasonable model for the unsaturated behavior of PRBs.


Asunto(s)
Compuestos Férricos , Contaminantes Químicos del Agua , Zeolitas , Agua , Suelo , Arena , Contaminantes Químicos del Agua/análisis
20.
Chemosphere ; 354: 141714, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38521106

RESUMEN

The widespread use of nanomaterials has raised the threat of nanoparticles (NPs) infection of soils and groundwater resources. This research aims to investigate three parameters including flow velocity, ionic strength (IS), and initial particle concentration effects on transport behavior and retention mechanism of functionalization form of graphene oxide with polyvinylpyrrolidone (GO-PVP). The transport of GO-PVP was investigated in a laboratory-scale study through saturated/unsaturated (Saturation Degree = 0.91) sand columns. Experiments were conducted on flow velocity from 1.20 to 2.04 cm min-1, initial particle concentration from 10 to 50 mg L-1, and IS of 5-20 mM. The retention of GO-PVP was best described using the one-site kinetic attachment model in HYDRUS-1D, which accounted for the time and depth-dependent retention. According to breakthrough curves (BTCs), the lower transport related to the rate of mass recovery of GO-PVP was obtained by decreasing flow velocity and initial particle concentration and increasing IS through the sand columns. Increasing IS could improve the GO-PVP retention (based on katt and Smax) in saturated/unsaturated media; katt increases from 2.81 × 10-3 to 3.54 × 10-3 s-1 and Smax increases from 0.37 to 0.42 mg g-1 in saturated/unsaturated conditions, respectively. Our findings showed that the increasing retention of GO-PVP through the sand column under unsaturated condition could be recommended for the reduction of nanoparticles danger of ecosystem exposure.


Asunto(s)
Grafito , Nanopartículas , Arena , Porosidad , Ecosistema , Concentración Osmolar , Dióxido de Silicio
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