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1.
Environ Pollut ; 349: 123903, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38599272

ABSTRACT

To investigate watershed remediation within a Total Maximum Daily Load program, this study examined the field-scale filtration performance of two specialty absorbents. The goal was to simultaneously remove nutrients and biological pollutants along Canal 23 (C-23) in the St. Lucie River Basin, Florida. The filtration system installed in the C-23 river corridor was equipped with either clay-perlite with sand sorption media (CPS) or zero-valent iron and perlite green environmental media (ZIPGEM). Both media were formulated with varying combinations of sand, clay, perlite, and/or recycled iron based on distinct recipes. In comparison with CPS, ZIPGEM exhibited higher average removal percentages for nutrients. Findings indicated that ZIPGEM could remove total nitrogen up to 49.3%, total Kjeldahl nitrogen up to 67.1%, dissolved organic nitrogen (DON) up to 72.9%, total phosphorus up to 79.6%, and orthophosphate up to 73.2%. Both ZIPGEM and CPS demonstrated similar efficiency in eliminating biological pollutants, such as E. coli (both media exhibiting an 80% removal percentage) and chlorophyll a (both media achieving approximately 95% removal). Seasonality effects were also evident in nutrient removal efficiencies, particularly in the case of ammonia nitrogen; the negative removal efficiency of ammonia nitrogen from the fifth sampling event could be attributed to processes such as photochemical ammonification, microbial transformation, and mineralization of DON in wet seasons. Overall, ZIPGEM demonstrated a more stable nutrient removal efficiency than CPS in the phase of seasonal changes.


Subject(s)
Environmental Restoration and Remediation , Filtration , Nitrogen , Phosphorus , Silicon Dioxide , Water Pollutants, Chemical , Filtration/methods , Water Pollutants, Chemical/analysis , Environmental Restoration and Remediation/methods , Environmental Restoration and Remediation/instrumentation , Florida , Water Purification/methods , Rivers/chemistry , Aluminum Oxide/chemistry , Escherichia coli , Chlorophyll A , Clay/chemistry , Iron/chemistry
2.
Environ Res ; 212(Pt A): 113208, 2022 09.
Article in English | MEDLINE | ID: mdl-35367430

ABSTRACT

The increasing needs of drinking water due to population growth requires seeking for new tap water sources. However, these large-scale tap water sources are oftentimes abundant with dissolved natural organic matter (NOM), such as tannic acid issue causing color in water. If not removed at the source locations beforehand, NOM would impact coagulation and flocculation unit, and/or become precursors to prompt the production of disinfectant by-products after chlorination in drinking water treatment. This study focuses on developing and testing a suite of cost-effective, scalable, adaptable, and sustainable sorption media that can be implemented near the source locations of tap water as a pretreatment option to remove color for a long-distance interbasin transfer. Within the five tested sorption media, a media recipe of Zero-valent-Iron and Perlite based Green Sorption Media (ZIPGEM) with ingredients of 85% sand, 5% clay, 6% zero-valent-iron (ZVI) and 4% perlite by volume stood out as the best option for color removal. Findings showed that ZIPGEM can maintain a color removal of ∼77% for about 14,080 min, maintaining the effluent concentration below 40 Pt-Co units given the influent condition of 175 ± 10 Pt-Co units. A recovery on the adsorption capacity of ZIPGEM was observed around 40,000 min due to synergetic effects among several different ingredients of recycled ZVI, clay, sand, and perlites. ZIPGEM can be applied to industrial wastewater treatment for dye removal as well.


Subject(s)
Drinking Water , Water Pollutants, Chemical , Water Purification , Clay , Iron , Sand , Water Pollutants, Chemical/analysis
3.
Sci Total Environ ; 819: 152886, 2022 May 01.
Article in English | MEDLINE | ID: mdl-34998770

ABSTRACT

This study investigated the removal of selected per- and polyfluoroalkyl substances (PFAS) from water via two green sorption media (IFGEM-7 and AGEM-2). Both selected green sorption media recipes contain sand (85-91%) and clay (3-4%), in addition to recycled iron (Fe) (5-7.5%) or aluminum (Al) (4.5% in AGEM-2 only). Batch and column studies were integrated and performed using the prescribed green sorption media recipes to determine their efficiencies in removing two most targeted PFAS, including perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). In the batch test, while the removal efficiencies of PFOS ranged from 27 to 46% and 23 to 42%, those for PFOA ranged from 6 to 16% and 5 to 18% when using IFGEM-7 and AGEM-2, respectively. The higher removal of PFOS than PFOA observed in both IFGEM-7 and AGEM-2 batch tests could be attributed to higher media affinity for sulfonate groups of PFOS when compared to the carboxylate groups of PFOA. In the column study, the initial removal (within 1 h) by IFGEM-7 was greater than 99% for PFOS and 28% for PFOA. When comparing different dynamic adsorption models, it appears that the non-linear equations could better describe the trend of experimental data compared to the linear forms of the Modified Dose Response model. Life expectancy calculations, performed for demonstration purposes of field applications, suggested that if IFGEM-7 were to be applied in a downflow filter box to treat a hypothetical volume of 60,000 L of water during an emergency response, and it may last for 1506 h (62.8 d) and 4.2 h for a target removal of 80% of PFOS and PFOA, respectively.


Subject(s)
Alkanesulfonic Acids , Fluorocarbons , Caprylates , Water
4.
Sci Rep ; 10(1): 21118, 2020 12 03.
Article in English | MEDLINE | ID: mdl-33273510

ABSTRACT

This study aimed to determine ANGPTL3 serum levels in healthy young lean and obese non-diabetic men during an oral glucose tolerance test (OGTT) and correlate them with anthropometric, biochemical and hormonal parameters. A case-control study was carried out and 30 young obese non-diabetic (23.90 ± 3.84 years and BMI 37.92 ± 4.85 kg/m2) and 28 age-matched healthy lean (24.56 ± 3.50 years and BMI of 22.10 ± 1.72 kg/m2) men were included in this study. The primary outcome measures were serum basal ANGPTL3 and ANGPTL3-area under the curve (AUC) levels. The percentage of body fat was measured by dual-energy X-ray absorptiometry and biochemical, hormonal and insulin resistance indices were determined. Basal ANGPTL3 and ANGPTL3-AUC levels were significantly elevated (p < 0.05) in young obese subjects compared with lean subjects and were positively and significantly associated with different anthropometric measurements. Fasting ANGPTL3 serum levels were positively correlated with fasting insulin, leptin, Leptin/Adiponectin index and triglyceride-glucose index. Moreover, ANGPTL3-AUC was negatively correlated with Matsuda index. In this regard, chronically high ANGPTL3 levels in young obese subjects might favor triglyceride-rich lipoprotein clearance to replenish triglyceride stores by white adipose tissue rather than oxidative tissues.


Subject(s)
Angiopoietin-like Proteins/blood , Diabetes Mellitus/blood , Obesity/blood , Angiopoietin-Like Protein 3 , Blood Glucose/metabolism , Fasting/blood , Glucose Tolerance Test , Humans , Insulin/blood , Insulin Resistance , Male , Obesity/complications , Young Adult
5.
Environ Pollut ; 266(Pt 1): 115172, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32712480

ABSTRACT

Recycled materials were used in three types of green sorption media for nutrient removal and possible recovery in high nutrient-laden agricultural discharge and stormwater runoff. The three types of green sorption media included in this comparative study were two new aluminum-based green environmental media (AGEM) and one existing iron-filings based green environmental media (IFGEM). The corresponding adsorption isotherm, thermodynamics, and kinetics models were simulated based on isotherm studies to determine their removal efficiency and potential for recovery of nitrate, phosphate, and ammonia when used as a soil amendment in crop fields or in a filter for water treatment. AGEM-2 exhibited the shortest contact time required to achieve nutrient removal above 80% with an average of 7 h, followed by AGEM-1 and IFGEM with 10.6 and 28 h, respectively. Natural soil was included as a control and exhibited minimal nutrient removal. Ammonia, which may be recovered as fertilizer for drop fields in a soil-water-waste nexus, was generated by all three green sorption media mixes, therefore indicating their potential for use as soil amendments in agricultural and forested land after engineering filter applications. The kinetics analysis indicated that nitrate adsorption follows pseudo-first-order kinetics, while phosphate adsorption follows pseudo-second-order kinetics. The Gibbs free energy indicated that most of the adsorption reactions proceeded as exothermic. Lastly, a few equilibrium models, including the Langmuir, Freundlich, First Modified Langmuir, Temkin, Jovanovic, and Elovich models, were ranked and three were selected for use with IFGEM, AGEM-1, and AGEM-2, respectively, as below: (1) Langmuir, (2) Freundlich, and (3) First Modified Langmuir, according to three indices.


Subject(s)
Water Pollutants, Chemical/analysis , Adsorption , Hydrogen-Ion Concentration , Kinetics , Nutrients , Thermodynamics
6.
Environ Res ; 188: 109815, 2020 09.
Article in English | MEDLINE | ID: mdl-32592942

ABSTRACT

Nonpoint sources pollution from agricultural crop fields and urbanized regions oftentimes have elevated concentrations of dissolved organic nitrogen (DON) in stormwater runoff, which are difficult for microbial communities to decompose. The impact of elevated DON can be circumvented through the use of green sorption media, such as Biosorption Activated Media (BAM) and Iron-Filing Green Environmental Media (IFGEM), which, as integral parts of microbial ecology, can contribute to the decomposition of DON. To compare the fate, transport, and transformation of DON in green sorption media relative to natural soil (control), a series of fixed-bed columns, which contain natural soil, BAM, and two types of IFGEM, respectively, were constructed to compare nutrient removal efficiency under three distinct stormwater influent conditions containing nitrogen and phosphorus. The interactions among six microbial species, including ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, complete ammonia oxidation (comammox) bacteria, anaerobic ammonium oxidation (anammox) bacteria, dissimilatory nitrate reduction to ammonium bacteria, and iron-reducing bacteria, were further analyzed from microbial ecology perspectives to determine the DON impact on nutrient removal in BAM and IFGEM. Natural soil was only able to achieve adequate DON transformation at the influent condition of lower nutrient concentration. However, the two types of IFGEM showed satisfactory nutrient removals and achieved greater transformation of DON relative to BAM when treating stormwater in all three influent conditions.


Subject(s)
Denitrification , Water Purification , Filing , Iron , Nitrogen , Oxidation-Reduction , Rain , Water Supply
7.
G3 (Bethesda) ; 10(5): 1585-1597, 2020 05 04.
Article in English | MEDLINE | ID: mdl-32265286

ABSTRACT

N-Glycanase 1 (NGLY1) deficiency is an ultra-rare, complex and devastating neuromuscular disease. Patients display multi-organ symptoms including developmental delays, movement disorders, seizures, constipation and lack of tear production. NGLY1 is a deglycosylating protein involved in the degradation of misfolded proteins retrotranslocated from the endoplasmic reticulum (ER). NGLY1-deficient cells have been reported to exhibit decreased deglycosylation activity and an increased sensitivity to proteasome inhibitors. We show that the loss of NGLY1 causes substantial changes in the RNA and protein landscape of K562 cells and results in downregulation of proteasomal subunits, consistent with its processing of the transcription factor NFE2L1. We employed the CMap database to predict compounds that can modulate NGLY1 activity. Utilizing our robust K562 screening system, we demonstrate that the compound NVP-BEZ235 (Dactosilib) promotes degradation of NGLY1-dependent substrates, concurrent with increased autophagic flux, suggesting that stimulating autophagy may assist in clearing aberrant substrates during NGLY1 deficiency.


Subject(s)
Endoplasmic Reticulum , Gene Expression Regulation , Endoplasmic Reticulum/metabolism , Humans , K562 Cells , Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase/genetics , Proteasome Endopeptidase Complex/metabolism
8.
Environ Res ; 184: 109338, 2020 05.
Article in English | MEDLINE | ID: mdl-32172072

ABSTRACT

In this study, a rapid infiltration basin (RIB) designed as green infrastructure for co-disposal of wastewater effluent and stormwater runoff was retrofitted for sustainable groundwater recharge after nitrogen removal. For comparison of nitrogen removal efficiency via different filtration media, the RIB was divided into two sub-basins for different filtration processes. One sub-basin was filled with a native sandy soil with about 2-4% clay (Control RIB), and the other sub-basin was modified with Biosorption Activated Media (BAM) (BAM RIB), for the enhancement of microbial nitrogen removal. The two sub-basins accept an equal amount of excess reclaimed wastewater in non-storm periods, and stormwater during periodic storm events. The infiltrate in both the BAM RIB and the Control RIB eventually reaches the Upper Floridan Aquifer. The seven microbial species involved in this microbial ecology study are nitrite oxidizing bacteria (NOB), ammonia oxidizing bacteria (AOB), anaerobic oxidation of ammonium (anammox) bacteria, complete ammonia oxidizer (Comammox) bacteria, denitrifiers, dissimilatory nitrate reduction to ammonium (DNRA) and ammonia-oxidizing archaea (AOA). The population dynamics study was conducted with the aid of the quantitative polymerase chain reaction (qPCR) for the quantification of the microbial gene population in support of microbial ecology discovery. The qPCR results demonstrated the competition effect between AOA, AOB, and Comammox, the inhibition effect between NOB and DNRA with the presence of anammox, and the complementary effect due to an abundance of NOB and AOB in the microbial ecology. Although, competition between denitrifiers and DNRA was expected to impact population dynamics, both microbial species were found to be the most predominant in both control and BAM RIBs. Research findings indicate that the use of BAM RIB achieves significantly efficient nitrogen removal driven by complementary effects in the microbial ecology.


Subject(s)
Nitrogen , Wastewater , Ammonia , Denitrification , Oxidation-Reduction , Soil
9.
Chemosphere ; 243: 125399, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31995869

ABSTRACT

Nutrient removal efficiency in green sorption media such as biosorption activated media (BAM) for treating stormwater runoff can be heavily influenced either on a short- or long-term basis by varying field conditions of linear ditches due to the presence of copper in stormwater runoff. It is also noticeable that the linear ditch undergoes physical or mechanical impacts from the traffic compaction, chemical impact of carbon sources from the nearby farmland, and biological impact from potential animal activities (such as gopher tortoises, moles, and ants). In the nitrogen cycle, two denitrification pathways, the dissimilatory nitrate reduction to ammonia and common denitrification, are deemed critical for such assessment. A fixed-bed column study was set up to mimic different linear ditch field conditions for BAM applications and measure the effect of short-and long-term copper addition on microbial dynamics given the varying decomposition of dissolved organic nitrogen (DON). The findings confirm that, as the denitrifiers (in the second pathway) were the dominant species, their population continued to grow and maintain small-sized cells for extracellular sequestration under long-term copper impact. Furthermore, the study indicated that the ammonia oxidizer comammox was found in higher quantities than ammonia oxidizing bacteria or archaea. An enormous amount of DON was released during this process to bind the copper ion and reduce its toxicity as the enzymatic cascade effect appeared. In addition, the long-term copper exposure posed salient inhibitory effects on the microbial community regardless of varying field conditions in BAM. Short-term copper toxicity exerted an important but varying role in the enzymatic cascade effect over different linear ditch field conditions in BAM.


Subject(s)
Copper/chemistry , Enzymes/metabolism , Nitrogen/isolation & purification , Water Purification/methods , Ammonia/metabolism , Carbon , Copper/metabolism , Denitrification , Enzymes/chemistry , Microbial Consortia/drug effects , Nitrates/metabolism
10.
Environ Res ; 181: 108915, 2020 02.
Article in English | MEDLINE | ID: mdl-31759643

ABSTRACT

Roadside drainage networks can result in changes to watershed hydrology and water quality. By acting as hydrological links between urban development, agricultural fields, and natural streams, roadside ditches may be modified by filling in some green sorption media to control nitrogen pollution. Biosorption activated media (BAM), one of the green sorption media, are composed of sand, tire crumb, and clay, which can remove nitrogen from stormwater and groundwater through integrated hydrological, chemophysical, and microbial processes. The fate and transport processes of interest are complicated by internal microbial processes including ammonification, nitrification, denitrification, and dissimilatory nitrate reduction to ammonium (DNRA), each of which is controlled by different microbial species in addition to some varying field conditions. In this study, BAM was tested in a suite of columns to address site-specific physical, chemical and biological concerns driven by in situ traffic compaction, carbon availability, and animal impact (such as gopher turtles, moles, and ants) all of which impose different impacts on nitrogen fate and transport processes that may be signified by changing dissolved organic nitrogen species (DONs). The traffic compaction condition resulted in the most suitable hydraulic retention time in the hydrological process, which is beneficial for the assimilation of DONs in a long-term carbon rich environment due to biofilm expansion. Denitrifiers were the most predominant microbial population and the microbial species of DNRA were the second most predominant one in all three field conditions. However, the relationship of denitrifiers and DNRA in BAM can be shifted from commensalism to competition or even inhibition after carbon addition in microbial ecology.


Subject(s)
Nitrogen , Rain , Waste Disposal, Fluid/methods , Groundwater , Nitrates , Water Purification , Water Supply
11.
Sci Total Environ ; 719: 134826, 2020 Jun 01.
Article in English | MEDLINE | ID: mdl-31879034

ABSTRACT

Removing excess nutrient from stormwater runoffs is necessary to protect the water quality of receiving water bodies such as rivers, lakes, springs, and groundwater aquifers. Silver Springs Springshed, located in the vicinity of Ocala, Florida, has received widespread attention from the local government and residents due to its long-term nutrient impact, which has resulted in eutrophication. Blanket filters containing Bio-sorption Activated Media (BAM) were implemented with different depths of the vadose zone in a stormwater retention basin. The design combined the interaction with groundwater as an innovative Best Management Practice can potentially boost the performance of nutrient removal. Selected storm runoffs were collected at multiple points that cover the runoff timeframe to determine the pollutant load. Infiltrating water samples were collected at various depths within BAM using lysimeters to validate the treatment effectiveness. Significant pollutant load reduction of nutrients was confirmed with highest 99% and 91% removal of nitrate and nitrite (NOx) and total nitrogen (TN) at the deep blanket filter (with more groundwater intrusion impacts) due to more effective denitrification and longer contact time. Yet the highest pollutant load reduction of 93% and 84% removal of NOx and TN was also observed at the shallow blanket filter (with less groundwater intrusion impacts). On the other hand, better pollutant load reduction of ammonia in the BAM layer was found at the shallow blanket filter presumably due to more available oxygen for nitrification.

12.
Rev. ecuat. neurol ; 27(3): 44-50, sep.-dic. 2018. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1004044

ABSTRACT

Resumen Introducción: La llegada en periodo de ventana terapéutica de un paciente con ictus isquémico al hospital depende de la identificación de las manifestaciones clínicas y el reconocimiento de que se trata de una urgencia médica. Métodos: Se realizó un estudio prospectivo, longitudinal, de corte transversal para el cual se diseñó una entrevista estructurada con preguntas cerradas. Objetivo. Evaluar el grado de conocimiento de la población acerca del infarto cerebral. Resultados: Se entrevistaron 135 sujetos sin diagnóstico de ictus, seleccionados al azar entre los familiares de pacientes. La edad media de fue de 42,6 años, predominaron las mujeres (92/68,1%) y el grado de instrucción medio. El 95,5% (129 sujetos) admitió tener poco conocimiento sobre el ictus. Solo el 11,1% señaló de forma correcta las manifestaciones clínicas; el síntoma más reconocido fue el amortiguamiento (59,3%) seguido de los trastornos del habla. El 80,9% identifican el ictus como una condición prevenible. Menos de la mitad de los participantes nombraron adecuadamente los factores de riesgo (66/48,9%). El 88,2% toma una actitud correcta ante los síntomas. Conclusiones: En el grupo de personas entrevistadas el conocimiento acerca de las manifestaciones y los factores de riesgo vascular es deficiente. Es necesario realizar campañas informativas dirigidas a mejorar el conocimiento de la enfermedad.


Summary Introduction: The arrival of patients with ischemic stroke to the hospital in the period of the therapeutic window, depends to a great extent on the identification of their clinical signs and the recognition that it is a medical emergency. Methods: A prospective, longitudinal, cross-sectional study was carried out, based on a structured interview with closed questions. The aim was to access the degree of the population's knowledge about the ischemic stroke. Results: A total of 135 subjects without a diagnosis of stroke were interviewed, randomly selected from the relatives of patients. The average age was 42.6 years, women predominated (92 / 68.1%), with an average level of education. 95.5% (129 subjects) admitted having little knowledge about stroke. Only 11.1% correctly indicated the clinical manifestations; The most recognized symptom was damping (59.3%) followed by speech disorders. 80.9% (109 respondents) identify stroke as a preventable condition. Less than half of the participants adequately named the risk factors (66 / 48.9%). 88.2% take a correct attitude to the symptoms. Conclusions: In the group of people interviewed there is a perception of risk regarding stroke, but knowledge about the manifestations and vascular risk factors is poor. It is necessary to carry out information campaigns aimed to improve knowledge of the disease.

13.
Med. UIS ; 22(3): 270-262, sept.-dic. 2009. graf, ilus
Article in Spanish | LILACS | ID: lil-606205

ABSTRACT

La necrólisis epidérmica tóxica es una patología de escasa ocurrencia, que se acompaña de mortalidad elevada y se caracteriza por lesiones cutáneas vesículo ampollosas que con frecuencia afecta la mucosa respiratoria, digestiva y ocular. Se presenta un caso de la enfermedad atendido en el Hospital Universitario de Santander en octubre del año 2007 desencadenado por el tratamiento con fenitoína – ácido valproico como terapia anticonvulsiva, con desenlace fatal y al cual se le practicó autopsia médico científica. Se pretende con este trabajo presentar una revisión del tema y analizar los factores relacionados con esta grave condición clínica...


Toxic epidermal necrolysis is an infrequent pathology, accompanied of high mortality risk in concordance with extension of comprised skin characterized for blisters. Frequently these are present in respiratory, digestive and ocular mucous. An autopsy case is presented occurred in Hospital Universitario de Santander in October 2007 of toxic epidermal necrolysis secondary to treatment with phenytoin associated with valproic acid as anticonvulsivant therapy for messial hippocampal sclerosis. It pretends with this work show a review and to analyze related factors with this condition...


Subject(s)
Autopsy , Phenytoin , Sclerosis , Stevens-Johnson Syndrome , Anticonvulsants , Blister
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