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Harmful Algal Blooms (HAB) have the potential to impact human health primarily through their possible cyanotoxins production. While conventional water treatments can result in the removal of unlysed cyanobacterial cells and low levels of cyanotoxins, during severe HAB events, cyanotoxins can break through and can be present in the treated water due to a lack of adequate toxin treatment. The objectives of this study were to assess the HAB conditions in drinking water sources in New Jersey and investigate relationships between environmental variables and cyanobacterial communities in these drinking water sources. Source water samples were collected monthly from May to October 2019 and analyzed for phytoplankton and cyanobacterial cell densities, microcystins, cylindrospermopsin, Microcystis 16S rRNA gene, microcystin-producing mcyB gene, Raphidiopsis raciborskii-specific rpoC1 gene, and cylindrospermopsin-producing pks gene. Water quality parameters included water temperature, pH, dissolved oxygen, specific conductance, fluorescence of phycocyanin and chlorophyll, chlorophyll-a, total suspended solids, total dissolved solids, dissolved organic carbon, total nitrogen, ammonia, and total phosphorus. In addition to source waters, microcystins and cylindrospermopsin were analyzed for treated waters. The results showed all five selected New Jersey source waters had high total phosphorus concentrations that exceeded the established New Jersey Surface Water Quality Standards for lakes and rivers. Commonly found cyanobacteria were identified, such as Microcystis and Dolichospermum. Site E was the site most susceptible to HABs with significantly greater HAB variables, such as extracted phycocyanin, fluorescence of phycocyanin, cyanobacterial cell density, microcystins, and Microcystis 16S rRNA gene. All treated waters were undetected with microcystins, indicating treatment processes were effective at removing toxins from source waters. Results also showed that phycocyanin values had a significantly positive relationship with microcystin concentration, copies of Microcystis 16S rRNA and microcystin-producing mcyB genes, suggesting these values can be used as a proxy for HAB monitoring. This study suggests that drinking water sources in New Jersey are vulnerable to forthcoming HAB. Monitoring and management of source waters is crucial to help safeguard public health.
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Research learning engagement is the basic element of master's students' innovation output, and the supervisor is the first responsible body for master's students' cultivation. Exploring the influence of the supervisor-postgraduate relationship on master's students' research learning engagement, with a focus on the mediating role of academic aspiration, is of great significance for the improvement of master's students' cultivation quality. We surveyed 569 master's students at a university in Wuhan, China, using 3 measurement tools: the Supervisor-Postgraduate Relationship Scale, the Research Learning Engagement Scale, and the Academic Aspirations Scale. The results showed that: (1) The supervisor-postgraduate relationship positively and significantly predicted master's students' research learning engagement, and academic aspiration played a fully mediating role in the process. (2) There were differences in the effects of the three dimensions of the supervisor-postgraduate relationship on master's students' research learning engagement, with research collaboration having the greatest total effect on the impact of master's students' research learning engagement. This study emphasizes the importance of the supervisor-postgraduate relationship and academic aspirations and provides some implications for improving the research learning engagement of master's students.
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Background: Hypertension is a major risk factor for the global burden of disease, and nutrition is associated with an increased risk of mortality from multiple diseases. Few studies have explored the association of nutritional risk with all-cause mortality and cardiovascular mortality in hypertension, and our study aims to fill this knowledge gap. Method: We included data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2016 on a total of 10,037 elderly patients with hypertension. The nutritional status was evaluated using the Geriatric Nutrition Risk Index (GNRI). Kaplan-Meier survival analysis was performed to analyze the survival rates of different nutritional risk groups. COX proportional risk regression models were used to analyze the predictive effect of GNRI on all-cause mortality and cardiovascular mortality in hypertensive patients. Restricted cubic splines (RCS) were used to explore the nonlinear relationship between GNRI and mortality. Result: The mean age of the hypertensive patients was 70.7 years. A total of 4255 (42.3%) all-cause mortality and 1207 (17.2%) cardiovascular mortality occurred during a median follow-up period of 106 months. Kaplan-Meier showed a more significant reduction in survival for the moderate to severe malnutrition risk of GNRI. The adjusted COX proportional hazards model showed that the hazard ratios for all-cause mortality and cardiovascular mortality in the moderate to severe malnutrition risk group for GNRI were 2.112 (95% CI, 1.377,3.240) and 2.604 (95% CI, 1.603,4.229), respectively. The RCS showed that increased GNRI was associated with a reduced risk of all-cause mortality and cardiovascular mortality risk reduction. Conclusion: Malnutrition exposure assessed by GNRI effectively predicts the risk of all-cause mortality and cardiovascular mortality in the elderly with hypertension.
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Some urban areas have more litter than others. Understanding the reason for this is important not only for dealing with urban littering but also for marine water quality because approximately 80% of the world's marine litter originates on land. This study aimed to better understand the quality and quantity of litter on sidewalks along with the sampling site's socio-economic attributes to better discern why some areas have more/different litter than others and what, if any, are the implications for a more tailored waste management strategy. We surveyed twice each of the 35 sites we selected from the Lower Passaic River watershed and the related Harbor Estuary within New Jersey, U.S.A. A total of 28,431 litter items were recorded with a total mass and volume of 245.8 kg and 4.7 m3, respectively. Floatable items accounted for 66% of all objects collected. Cigarette butts were the most numerous among all items (28%) and represented 43% of the total floatable items, the remaining 57% being represented by potentially recyclable items such as plastic, rubber, and Styrofoam. Stepwise linear regression was used to explore the relationship between the litter collected and various predictors. Among others, the results suggest the importance of strategically placing collection bins around properties with relatively lower assessed values, outdoor smoking areas, close to schools, and places where people predominantly walk to their destination. Possible management strategies include prohibiting single use plastic bags, limiting foam food ware, public education, and outreach.
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Good water quality safeguards public health and provides economic benefits through recreational opportunities for people in urban and suburban environments. However, expanding impervious areas and poorly managed sanitary infrastructures result in elevated concentrations of fecal indicator bacteria and waterborne pathogens in adjacent waterways and increased waterborne illness risk. Watershed characteristics, such as urban land, are often associated with impaired microbial water quality. Within the proximity of the New York-New Jersey-Pennsylvania metropolitan area, the Musconetcong River has been listed in the Clean Water Act's 303 (d) List of Water Quality-Limited Waters due to high concentrations of fecal indicator bacteria (FIB). In this study, we aimed to apply spatial stream network (SSN) models to associate key land use variables with E. coli as an FIB in the suburban mixed-land-use Musconetcong River watershed in the northwestern New Jersey. The SSN models explicitly account for spatial autocorrelation in stream networks and have been widely utilized to identify watershed attributes linked to deteriorated water quality indicators. Surface water samples were collected from the five mainstem and six tributary sites along the middle section of the Musconetcong River from May to October 2018. The log10 geometric means of E. coli concentrations for all sampling dates and during storm events were derived as response variables for the SSN modeling, respectively. A nonspatial model based on an ordinary least square regression and two spatial models based on Euclidean and stream distance were constructed to incorporate four upstream watershed attributes as explanatory variables, including urban, pasture, forest, and wetland. The results indicate that upstream urban land was positively and significantly associated with the log10 geometric mean concentrations of E. coli for all sampling cases and during storm events, respectively (p < 0.05). Prediction of E. coli concentrations by SSN models identified potential hot spots prone to water quality deterioration. The results emphasize that anthropogenic sources were the main threats to microbial water quality in the suburban Musconetcong River watershed. The SSN modeling approaches from this study can serve as a novel microbial water quality modeling framework for other watersheds to identify key land use stressors to guide future urban and suburban water quality restoration directions in the USA and beyond.
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Escherichia coli , Rios , Humanos , Rios/microbiologia , New Jersey , Monitoramento Ambiental/métodos , Microbiologia da Água , Bactérias , Fezes/microbiologiaRESUMO
Objective: Osteoarthritis (OA) is a degenerative chronic disease that most often occurs in the knee joint. Studies have shown that some food supplements, such as curcumin and chondroitin sulfate, are effective in treating knee osteoarthritis (KOA) by exhibiting different protective effects. In this study, we further investigated the combined therapeutic effects of curcumin and chondroitin sulfate on cartilage injury in rats with arthritis. Methods: An experimental KOA model was induced by monosodium iodoacetate (MIA) in rats. All rats were randomly divided into five groups: Ctrl (control), model (saline), Cur (20 mg/kg curcumin in saline), CS (100 mg/kg chondroitin sulfate in saline), and CA (20 mg/kg curcumin and 100 mg/kg chondroitin sulfate in saline); drugs were given 2 weeks after MIA injection. The histomorphological changes of cartilage were observed by safranin fast green staining, H&E staining, and micro-CT scanning. Also, the levels of PGE2, TNF-α and IL-1ß in the arthral fluid and serum were determined by the ELISA kits. The activities of SOD, CAT, COMP, MMP-3, and type II collagen were detected by biochemical kits. The expressions of TLR4, p-NF-κB, NF-κB, and COX-2 in cartilage were detected by Western blot. Results: Data show that serum levels of IL-1ß (p < 0.05), SOD (p < 0.0001), and MMP-3 (p < 0.001) were downregulated significantly in the CA group when compared to those in the model group. Meanwhile, obvious repair of cartilage with higher contains collagen II (p < 0.0001) could be observed in the CA group than the ones in Cur or CS group. In addition, significant downregulation of the expression of p-p65/p65 (p < 0.05) was found in the CA group. Conclusion: Our findings showed that combined administration of curcumin and chondroitin sulfate could exert better repair for KOA in rat models. This may hold great promise for discovering potential drugs to treat KOA and may improve treatment options for it.
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Trace elements in aquatic environments pose a risk to biological communities; this study investigates the total concentrations of arsenic (As), silver (Ag), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), selenium (Se), lead (Pb), and zinc (Zn) within muscle, carapace, liver, and adipose tissues of diamondback terrapins and common snapping turtles in New Jersey. The effects of tissue type, sex, size, and location upon trace element accumulation were studied. The data obtained indicates that within diamondback terrapins and common snapping turtles, trace element accumulations displayed a significant difference among tissue types and sex (p < 0.005). The data indicates that Ag, Cd, Cu, and Hg can accumulate within the liver of diamondback terrapin. Se was found to accumulate in the livers of both diamondback terrapin and common snapping turtles. The highest mean concentrations of Co, Cr, Ni, and Pb were found in the carapace of both turtle species. Sex was found to have an impact on As, Hg, and Zn accumulation within different tissue types of diamondback terrapins. Diamondback terrapin males were found to have higher concentrations of As within the carapace. Diamondback terrapin females possessed higher concentrations of Hg in muscle tissues and Hg and Zn in the carapace. Turtle size and collection location land type and land cover did not display any correlation with trace element bioaccumulation for either species.
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Mercúrio , Oligoelementos , Tartarugas , Animais , Feminino , Masculino , New Jersey , Tartarugas/fisiologiaRESUMO
As contact with high concentrations of pathogens in a waterbody can cause waterborne diseases, Escherichia coli is commonly used as an indicator of water quality in routine public health monitoring of recreational freshwater ecosystems. However, traditional processes of detection and enumeration of pathogen indicators can be costly and are not time-sensitive enough to alarm recreational users. The predictive models developed to produce real-time predictions also have various methodological challenges, including arbitrary selection of explanatory variables, deterministic statistical approach, and heavy reliance on correlation instead of the more rigorous multivariate regression analyses, among others. The objective of this study is to address these challenges and develop a cost-effective and timely alternative for estimating pathogen indicators using real-time water quality and quantity data. As a case study we use New Jersey, where pathogens represent the most common cause of impairment for water quality, and Passaic and Pompton rivers, which are among the largest in the state and the country. We used Membrane Filtration Method and mColiblue24 media to enumerate Escherichia coli in a total of 69 water samples collected from April to November 2016 from the two rivers. We also collected data on environmental variables concurrently and performed stepwise and logistic regression analyses to address the said methodological challenges and determine the variables significantly predicting whether or not the Escherichia coli count was above prescribed levels for recreation activities. The results show that source water, higher specific conductance, lower pH, and cumulative rainfall for the 72 h antecedent the sampling significantly impacted the density of Escherichia coli. In addition to using the Bagging technique to validate the results, we also assessed Whole Model Tests, R2, Entropy R2, and Misclassification Rates. This approach improves the prediction of bacteria counts and their use in informing the potential safety/hazard of that waterbody for recreational activities.
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Escherichia coli , Rios , Ecossistema , Monitoramento Ambiental , New Jersey , Microbiologia da ÁguaRESUMO
Mercury contamination in consumed foods poses a significant threat to human health globally. The consumption of mercury-contaminated turtle meat is of special concern due to mercury's capability to bioaccumulate and biomagnify in organisms. Turtles are long-lived predators, allowing for a high degree of bioaccumulation and biomagnification of contaminants. In the U.S., diamondback terrapins (Malaclemys terrapin) are legally harvested in several states throughout their range. Harvested turtles are usually sold to both local and global markets mainly for human consumption, which results in a human consumption threat. The objective of this study was to analyze mercury concentrations to determine if the consumption of terrapins poses a threat to human health. Diamondback terrapins were collected from two study sites: Cape May and Hackensack Meadowlands, New Jersey, relatively pristine and contaminated estuaries, respectively. Turtle carapace, blood, and muscle samples were analyzed for total mercury concentrations. Results showed significant difference between study sites and females' and males' blood mercury concentrations. Similarly, results showed blood mercury correlated with carapace length. Results also showed that 50% of Cape May muscle samples and 72.7% Meadowlands muscles samples surpassed the New Jersey sensitive threshold of 0.18 ppm. Furthermore, 27.3% of Cape May muscle samples and 45.5% of Meadowlands muscles samples surpassed the U.S. Environmental Protection Agency's mercury threshold of 0.3 ppm for seafood consumption for the general public. Overall, the harvest of terrapins could pose a threat to consumers, and terrapins should be monitored closely or possibly banned for human consumption, especially in areas with known contamination history.
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Contaminação de Alimentos/análise , Carne/análise , Mercúrio/análise , Tartarugas/metabolismo , Poluentes Químicos da Água/análise , Animais , Estuários , Feminino , Humanos , Masculino , New Jersey , Tartarugas/fisiologiaRESUMO
In this study, soil samples were collected at 22 sites in Liberty State Park, New Jersey, in 2005, for metal enrichment and potential ecological risk assessment. The geoaccumulation index (I geo) showed that enrichment levels of trace metals followed an order of Cu > Pb > Zn > As > Cr > Hg while the potential ecological risk factor ([Formula: see text]) indicated that the potential ecological risk of the metals was in the order of Cu > Pb > As > Hg > Zn > Cr. Among these 22 sites, this investigation identified 9 sites at moderate ecological risk, 3 sites at considerable ecological risk, and 4 sites at high ecological risk according to the potential ecological risk index (RI). Hierarchical cluster analysis (CA) of soil metal concentrations separated the study sites into four groups, which are supported by the significant difference in RI values. Geographically, three regions in the Liberty State Park brownfield site were determined based on the CA results and RI values. Subarea 1 had low ecological risk while subareas 2 and 3 had a greater potential for ecological risk. Significant correlations of Pb with Cr and Zn were observed in subareas 2 and 3, respectively. This study shows that statistical approaches coupled with a risk assessment index provide a more comprehensive interpretation of land contamination than a single approach in support of planning land redevelopment.
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Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Ecologia , New Jersey , New York , Cidade de Nova Iorque , Medição de Risco , UrbanizaçãoRESUMO
Although ferrate(VI) has long been recognized as a multi-purpose treatment agent, previous investigations regarding ferrate(VI) for addressing harmful algal blooms (HABs) impacts in drinking water treatment only focused on a single HAB pollutant (e.g. algal cells or algal toxins). Moreover, the performance of ferrate(VI)-driven coagulation was poorly investigated in comparison with ferrate(VI) oxidation, though it has been widely acknowledged as a major ferrate(VI) treatment mechanism. We herein reported ferrate(VI) as an emerging agent for simultaneous and effective removal of algal cells and toxins in a simulated HAB-impacted water. Ferrate(VI)-driven oxidation enabled algal cell inactivation and toxin decomposition. Subsequently, Fe(III) from ferrate(VI) reduction initiated an in-situ coagulation for cell aggregation. Cell viability (initial 4.26 × 104 cells/mL at pH 5.5 and 5.16 × 104 cells/mL at pH 7.5) decreased to 0.0% at ≥ 7 mg/L Fe(VI) at pH 5.5 and 7.5, respectively. Cell density and turbidity were dramatically decreased at pH 5.5 once ferrate(VI) doses were beyond their respective threshold levels, which are defined as minimum effective iron doses (MEIDs). However, the particulate removal at pH 7.5 was poor, likely because the coagulation was principally driven by charge neutralization and a higher pH could not sufficiently lower the particle surface charge. Meanwhile, algal toxins (i.e., microcystins) of 3.98 µg/L could be substantially decomposed at either pH. And the greater degradation achieved at pH 5.5 was due to the higher reactivity of ferrate(VI) at the lower pH. This study represents the first step toward the ferrate(VI) application as a promising approach for addressing multiple HABs impacts for water treatment.
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Água Potável/química , Recuperação e Remediação Ambiental/métodos , Proliferação Nociva de Algas/efeitos dos fármacos , Ferro/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Compostos Férricos , Microcistinas , OxirreduçãoRESUMO
Understanding mechanisms that control plant root metal assimilation in soil is critical to the sustainable management of metal-contaminated land. With the assistance of the synchrotron X-ray fluorescence technique, this study investigated possible mechanisms that control the localization of Fe, Cu, Mn, Pb and Zn in the root tissues of Typha latifolia L. collected from a contaminated wetland. Metal localizations especially in the case of Fe and Pb in the dermal tissue and the vascular bundles were different. Cluster analysis was performed to divide the dermal tissue into iron-plaque-enriched dermal tissue and regular dermal tissue based on the spatial distribution of Pb and Fe. Factor analysis showed that Cu and Zn were closely correlated to each other in the dermal tissues. The association of Cu, Zn and Mn with Fe was strong in both regular dermal tissue and iron-plaque-enriched dermal tissue, while significant (p < 0.05) correlation of Fe with Pb was only observed in tissues enriched with iron plaque. In the vascular bundles, Zn, Mn and Cu showed strong association, suggesting that the localization of these three elements was controlled by a similar mechanism. Iron plaque in the peripheral dermal tissues acted as a barrier for Pb and a buffer for Zn, Cu and Mn. The Casparian strip regulated the transportation of metals from dermal tissues to the vascular bundles. The results suggested that the mechanisms controlling metal localization in root tissues varied with both tissue types and metals.
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Metais/farmacocinética , Raízes de Plantas/metabolismo , Poluentes do Solo/farmacocinética , Espectrometria por Raios X/métodos , Síncrotrons , Typhaceae/metabolismo , Metais/análise , Raízes de Plantas/química , Distribuição Tecidual , Typhaceae/químicaRESUMO
OBJECTIVE: To observe metabolomic changes in urine of chronic superficial gastritis (CSG) patients with Pi-qi deficiency syndrome (PQDS) or Pi-Wei dampness-heat syndrome (PWDHS), thereby providing scientific evidence for syndrome typing of them. METHODS: Urine samples were collected from CSG patients with PQDS/PWDHS and healthy volunteers, 10 in each group. Proton nuclear magnetic resonance spectroscopy (1H-NMR) based metabonomic analysis was performed on urine samples. Contents of related biomarkers were analyzed by principal component analysis (PCA), partial least square discriminant analysis (PLS-DA), and urivariate statistical analysis. RESULTS: PLS-DA analysis showed that metabolites among CSG patients with PQDS/PWDHS and healthy volunteers could be mutually distinguished. Seven differentially identified metabolites were screened from urines of CSG patients with PQDS and healthy volunteers included glutamate, methionine, α-oxoglutarate, dimethylglycine, creatinine, taurine, and glucose. Four differentially identified metabolites were screened from urines of CSG patients with PWDHS and healthy volunteers included 2-hydroxybutyric acid, trimethylamine oxide, taurine, and hippuric acid. Eleven differentially identified metabolites were screened from urines of CSG patients with PQDS and PWDHS included fucose, ß-hydroxybutyric acid, alanine, glutamate, methionine, succinic acid, citric acid, creatinine, glucose, hippuric acid, and lactic acid. CONCLUSION: The metabolic differences of CSG patients PQDS and PWDHS mainly manifested in glycometabolism, lipid metabolism, and amino acids catabolism, and 1H-NMR based metabonomics may be used in classified study of Chinese medical syndrome typing.
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Gastrite/urina , Medicina Tradicional Chinesa , Espectroscopia de Prótons por Ressonância Magnética , Biomarcadores/urina , Análise Discriminante , Temperatura Alta , Humanos , Hidroxibutiratos , Ácidos Cetoglutáricos , Análise dos Mínimos Quadrados , Metaboloma/fisiologia , Metabolômica , Análise de Componente Principal , Qi , SíndromeRESUMO
Two different methods are commonly used to delineate and characterize wetlands. The U.S. Army Corps of Engineers (ACOE) delineation method uses field observation of hydrology, soils, and vegetation. The U.S. Fish and Wildlife Service's National Wetland Inventory Program (NWI) relies on remote sensing and photointerpretation. This study compared designations of wetland status at selected study sites using both methods. Twenty wetlands from the Wetland Boundaries Map of the Ausable-Boquet River Basin (created using the revised NWI method) in the Ausable River watershed in Essex and Clinton Counties, NY, were selected for this study. Sampling sites within and beyond the NWI wetland boundaries were selected. During the summers of 2008 and 2009, wetland hydrology, soils, and vegetation were examined for wetland indicators following the methods described in the ACOE delineation manual. The study shows that the two methods agree at 78 % of the sampling sites and disagree at 22 % of the sites. Ninety percent of the sampling locations within the wetland boundaries on the NWI maps were categorized as ACOE wetlands with all three ACOE wetland indicators present. A binary linear logistic regression model analyzed the relationship between the designations of the two methods. The outcome of the model indicates that 83 % of the time, the two wetland designation methods agree. When discrepancies are found, it is the presence or absence of wetland hydrology and vegetation that causes the differences in delineation.
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Classificação/métodos , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Modelos Teóricos , Rios , Áreas Alagadas , Hidrologia/métodos , Modelos Logísticos , New York , Solo/química , Estados Unidos , United States Government AgenciesRESUMO
This study, conducted at a brownfield site in New Jersey, USA, investigated factors controlling V uptake and translocation in naturally assembled plant species. Six dominant species were collected from 22 stations in the study area. We found that V concentration in the plants decreased in a sequence of root>leaf>stem. No significant differences were found among the six dominant plant species in terms of root V uptake efficiency (V BCF) and V root to shoot translocation (V TF). Although soil pH and TOC did not show significant impact on V accumulation in the roots, soil labile V content showed significant positive linear correlation (p<0.05) with plant root V. Non-linear regression analysis indicates that V translocation efficiency decreases with increasing concentration in the soil, implying that excessive V in the soil might inhibit its absorption by the plant roots. Leaf V concentration was constant in all the plant species regardless of the variation in soil V concentration. The study shows that the six dominant plant species on site had limited amount of V translocated to the aerial part of the plant.
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Locais de Resíduos Perigosos , Plantas/química , Poluentes do Solo/análise , Vanádio/análise , Biodegradação Ambiental , New Jersey , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , SoloRESUMO
Synchrotron X-ray microfluorescence and X-ray absorption near-edge microstructure spectroscopy techniques were applied to Typha latifolia (cattail) root sections and rhizosphere soils collected from a brownfield site in New Jersey to investigate lead (Pb) accumulation in T. latifolia roots and the role of iron (Fe) plaque in controlling Pb uptake. We found that Pb and Fe spatial distribution patterns in the root tissues are similar with both metals present at high concentrations mainly in the epidermis and at low concentrations in the vascular tissue (xylem and phloem), and the major Pb and Fe species in T. latifolia root are Pb(II) and Fe(III) regardless of concentration levels. The sequestration of Pb by T. latifolia roots suggests a potential low-cost remediation method (phytostabilization) to manage Pb-contaminated sediments for brownfield remediation while performing wetland rehabilitation.
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Ferro/análise , Chumbo/análise , Raízes de Plantas/química , Poluentes do Solo/química , Typhaceae/química , Biodegradação Ambiental , New Jersey , Epiderme Vegetal/química , Solo/química , Áreas Alagadas , Espectroscopia por Absorção de Raios XRESUMO
Rhizosphere soil and dominant plant samples were collected at a brownfield site in New Jersey, USA, during summer 2005 to evaluate plant metal uptake from the contaminated soils. Metal concentrations varied from 4.25 to 978 µg g(-1) for As, 9.68-209 µg g(-1) for Cr, 23.9-1870 µg g(-1) for Cu, and 24.8-6502 µg g(-1) for Zn. A wide range of metal uptake efficiencies in the roots, stems and leaves was found in this study. Data showed that (1) Betula populifolia has high Zn, Cu and As accumulations in the root, and high concentrations of Cu and Zn in the stem and the leaf; (2) Rhus copallinum has high accumulation of Zn and Cr in the leaf and Cu in the stem; (3) Polygonum cuspidatum has high accumulations of Cu and As in the root; and (4) Artemisia vulgaris shows high Cu accumulation in the leaf and the stem.
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Metais/análise , Plantas/química , Poluentes do Solo/análise , Áreas Alagadas , Biodegradação Ambiental , Monitoramento Ambiental , Metais/metabolismo , Modelos Químicos , New Jersey , Plantas/metabolismo , Poluentes do Solo/metabolismoRESUMO
Water chestnut (Trapa natans L.), an annual aquatic plant with floating leaves was first introduced into North America in 1874. Since then, wild populations have quickly become established in many locations within Northeastern USA. Due to its detrimental effects on the overall health of aquatic ecosystems, millions of dollars have been spent to control the water chestnut infestations in the North America through mechanical harvesting and manual removal, with limited success. The potential for continued expansion of the infestations demonstrates an urgent need for an effective control method. This study examined the potential of ultrasound application as an alternative control strategy for water chestnut management. Various frequencies and amplitudes of ultrasound generated by submerged transducers were applied directly to water chestnuts harvested from Lake Champlain. Substantial damages on water chestnut cells as well as penetrated petitoles were observed at the following tested frequencies of ultrasound, 20 kHz, 187 kHz, 469 kHz, 519 kHz and 2.34 MHz. Among them, 20 kHz ultrasound of 1.9 MPa acoustic pressure amplitude demonstrated the most significant damages within 10 s of ultrasound exposure. The treated plants started to die within 72 h and the mortality rate of water chestnut plants treated with the ultrasound application was 100%.