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1.
Mar Pollut Bull ; 203: 116486, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38781801

RESUMEN

In recent years, plastic pollution in the environment has also increased due to the increasing production and consumption of plastics worldwide. The presence of microplastics (MPs) in the environment from different sources is observed almost everywhere, especially in aquatic environments. A standard method for sampling, identification, and quantification of MPs in wastewater has not yet been established. In this study, it was aimed to determine the MPs and their characteristics in the effluent of an advanced biological domestic wastewater treatment plant. The seasonal changes of MPs in a year were revealed. Pre-treatments suitable for the studied wastewater were developed for visual determination of MPs. Fibers are the dominant type of MPs, with numbers ranging between 32.0 and 95.5 particle/L. MPs in five different polymer structures were determined by FTIR analysis. These are Polyethylene, Polypropylene, Polyester, Polyurethane and Polyethylene terephthalate. The results were evaluated according to QA/QC and determined to meet the standards.

2.
Chemosphere ; 352: 141314, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38286307

RESUMEN

Currently, the vast majority of studies on microplastics (MPs) focus on determining the quantity and presence of these particles in various receiving environments and their treatment in domestic wastewater treatment plants. However, little research has been conducted on the treatment of microplastics in industrial effluent. Therefore, in this study, effluent samples from the cooling water tank of a local food packaging manufacturing company were analyzed to determine the presence and quantity of MPs for the first time. MPs removal from industrial wastewater using the electrocoagulation (EC) method was optimized using the Box Behnken Design (BBD). A second-order model was developed to estimate the microplastic removal efficiency, and the R2, adjusted R2, and predicted R2 of the model were 0.9994, 0.9985, and 0.9962, respectively. The optimal reaction parameters resulting in the maximum removal rate of microplastics (99 %) were determined to be pH 6.74, current density of 3.16 mA cm-2, and duration of 13.58 min. The cost of microplastic treatment per m3 of wastewater in the EC system, operated under optimal conditions, was calculated as 0.125 $. In this study, it was concluded that the EC process is a highly efficient technique for the removal of MPs from industrial wastewater at a low cost. Determining the most favorable conditions with BBD for the EC process at the feasibility stage of treatment plants will provide economic benefits and increase treatment efficiency during the installation of large-scale plants.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Microplásticos , Plásticos , Eliminación de Residuos Líquidos/métodos , Embalaje de Alimentos , Contaminantes Químicos del Agua/análisis , Electrocoagulación/métodos
3.
Int J Neurosci ; : 1-11, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38289414

RESUMEN

OBJECTIVE: The primary objective of this study is to address the challenge posed by the increasing number of variants of unknown clinical significance (VUS) within the GABRD gene, which encodes the δ subunit of γ-Aminobutyric acid type A receptors. The focus is on predicting the most pathogenic GABRD VUS to enhance precision medicine and improve our understanding of relevant pathophysiology. METHODS: The study employs a combination of in silico algorithms to analyze 82 variants of unknown clinical significance of GABRD gene sourced from the ClinVar database. Initially, separate algorithms based on sequence homology are utilized to assess this variant set. Subsequently, consensus variants predicted as pathogenic undergo further evaluation through a web server employing an algorithm based on structural homology. The resulting 11 variants are then validated using in silico tools that assess variant effects based on genetic and molecular data. The evaluation includes consideration of disease association and protein stability due to amino acid substitutions. RESULTS: The study identifies specific variants (L111R, R114C, D123N, G150S, and L243P) in the coding region of the GABRD gene, which are predicted as deleterious by multiple algorithms. These variants are evolutionarily conserved, mapped onto the extracellular domain of the δ subunit, and associated with idiopathic generalized epilepsy. CONCLUSIONS: The findings suggest structural or functional consequences that lead to pathogenicity, offering valuable insights for wet-lab experimentation. Besides, the findings contribute to the validation of clinically significant genetic variants in the GABRD gene, which is critical for epilepsy precision medicine.

4.
J Community Genet ; 15(2): 147-161, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38127180

RESUMEN

Wikipedia, the open crowdsourced encyclopedia that anyone can edit, ranks among the top ten most-visited websites globally. Its integration into university curriculum as an innovative educational tool is a slowly growing trend; however, many higher education institutions have yet to fully grasp its potential. In response, a specific optional module for Wikipedia editing, designed for the selected undergraduate science courses at the School of Advanced Studies, Russia, was implemented as an optional extra credit service-learning activity, a teaching methodology combining meaningful service to the community with curriculum-based learning. Students who chose to participate and those who preferred not to participate in the activity were invited to participate in a research project to explore their perspectives and experiences. In total, five sessions of focus group discussions were conducted with participants (12 females and 2 males) in one set and non-participants (5 females and 4 males) in another to identify students' perspectives on themes such as their interest in science, reasons for their choices, and their expectations before the activity while post-experience focus group discussions were used to identify the perspectives of participant students on themes, encompassing contribution of the service-learning activity, acquisition of new skills, and the development of prosocial behaviors. Students' opinions on integrating social responsibility topics into the curriculum were also explored. The results extracted from these focus group discussions, analyzed through consensual coding, revealed factors promoting student participation, like interest in the subject, novelty of the activity, and grade improvement opportunities, as well as factors deterring participation, such as concerns about academic benefits, workload, and time constraints. Furthermore, the results demonstrated that Wikipedia editing serves as a novel teaching methodology, promoting student learning and development in digital literacy and information literacy, which are among the twenty-first-century skills. Interestingly, at the same time, not all students could address the value of contributing to open, crowdsourced knowledge for public service or interpret this activity as an academic service-learning. These suggest that Wikipedia editing is an innovative teaching approach, fostering students' learning and development while also indicating its potential to enhance students' understanding of responsible citizenship and public service in the digital age.

5.
Heliyon ; 9(9): e20218, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809401

RESUMEN

Critical for brain development, neurodevelopmental and network disorders, the GABRA1 gene encodes for the α1 subunit, an abundantly and developmentally expressed subunit of heteropentameric gamma-aminobutyric acid A receptors (GABAARs) mediating primary inhibition in the brain. Mutations of the GABAAR subunit genes including GABRA1 gene are associated with epilepsy, a group of syndromes, characterized by unprovoked seizures and diagnosed by integrative approach, that involves genetic testing. Despite the diagnostic use of genetic testing, a large fraction of the GABAAR subunit gene variants including the variants of GABRA1 gene is not known in terms of their molecular consequence, a challenge for precision and personalized medicine. Addressing this, one hundred thirty-seven GABRA1 gene variants of unknown clinical significance have been extracted from the ClinVar database and computationally analyzed for pathogenicity. Eight variants (L49H, P59L, W97R, D99G, G152S, V270G, T294R, P305L) are predicted as pathogenic and mapped to the α1 subunit's extracellular domain (ECD), transmembrane domains (TMDs) and extracellular linker. This is followed by the integration with relevant data for cellular pathology and severity of the epilepsy syndromes retrieved from the literature. Our results suggest that the pathogenic variants in the ECD of GABRA1 (L49H, P59L, W97R, D99G, G152S) will probably manifest decreased surface expression and reduced current with mild epilepsy phenotypes while V270G, T294R in the TMDs and P305L in the linker between the second and the third TMDs will likely cause reduced cell current with severe epilepsy phenotypes. The results presented in this study provides insights for clinical genetics and wet lab experimentation.

6.
Med Oncol ; 40(1): 42, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36472705

RESUMEN

In this study, BALB/c mice with Ehrlich solid tumors were used to examine the effect of Achillea millefolium L. (AM) extract on the Ehrlich ascites tumor (EAT) model, which is one of the experimental cancer models. Also known as yarrow and plant, AM has antioxidant, anti-inflammatory, antibacterial and antitumor properties. In our study, 57 male BALB/c type mice, 8-10 weeks old, weighing 25-30 g, were used. Mice were divided into two groups. Ehrlich Solid Tumor group: Negative Control Group (ENC), Positive Control Group (EPC), and Treatment Group (TG) (TNCAM-200 mg/kg, TPCAM-400 mg/kg). EPC and TG were given to EAT cells. Each EAT contained 1 × 106 (will be 6 out of 10: so:000000) EAT cells, 0.1 ml of phosphate-buffered saline (PBS) was administered subcutaneously (s.c.) to the nape of mice. Then It was awaited for solid tumor formation. AM extract was administered intraperitoneally (i.p.) to TG for 17 days to mice. AM extract was found to have a curative effect on areas of inflammation, bleeding, and necrosis in treatment groups treated with AM extract alone. The treatment groups showed nearly normal histological results compared to the positive control group. According to the results, the TPCAM-400 mg/kg group had a more significant histological impact than the TNCAM-200 mg/kg group. In terms of tumor growth, tumor length, tumor volume, and tumor weight, AM extract did not show significant effects. However, in the light of histological findings, promising results of AM were observed in mice in which Ehrlich Solid Tumor was formed.


Asunto(s)
Neoplasias , Animales , Ratones
7.
Turk Neurosurg ; 32(4): 618-624, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35416258

RESUMEN

AIM: To evaluate the impact of carnosine on Purkinje neurons in rats exposed to a 900 Mhz electromagnetic field. MATERIAL AND METHODS: This study evaluated 24 rats divided into the following three different groups: a control group, a group exposed to the electromagnetic field, and a group that was injected with carnosine while being exposed to the electromagnetic field. The electromagnetic field group was exposed to a 900 Mhz electromagnetic field for an hour daily over 28 days. Thereafter, stereological analysis was performed histologically on cerebellar sections, and the number of Purkinje cells were counted. RESULTS: The electromagnetic field group had remarkably fewer Purkinje cell compared to control. The electromagnetic field group plus 20 mg of carnosine had significantly more total Purkinje cells compared to the electromagnetic field group (p < 0.05). CONCLUSION: The present study showed that electromagnetic field exposure decreases the number of Purkinje cell, whereas carnosine protected the cerebellum from neural damage induced by electromagnetic field exposure.


Asunto(s)
Carnosina , Células de Purkinje , Animales , Carnosina/farmacología , Recuento de Células , Cerebelo/patología , Campos Electromagnéticos , Células de Purkinje/efectos de los fármacos , Células de Purkinje/patología , Ratas
9.
Adv Exp Med Biol ; 1305: 203-230, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33834402

RESUMEN

The research of depression genetics has been occupied by historical candidate genes which were tested by candidate gene association studies. However, these studies were mostly not replicable. Thus, genetics of depression have remained elusive for a long time. As research moves from candidate gene association studies to GWAS, the hypothesis-free non-candidate gene association studies in genome-wide level, this trend will likely change. Despite the fact that the earlier GWAS of depression were not successful, the recent GWAS suggest robust findings for depression genetics. These altogether will catalyze a new wave of multidisciplinary research to pin down the neurobiology of depression.


Asunto(s)
Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Depresión/genética , Predisposición Genética a la Enfermedad/genética , Humanos , Polimorfismo de Nucleótido Simple
10.
J Integr Neurosci ; 20(1): 173-184, 2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33834705

RESUMEN

γ-Aminobutyric acid type A receptors (GABAARs) are GABA gated heteropentameric chloride channels responsible for the adult brain's primary inhibition. In specific brain cells, such as in the hippocampus, one of the subtypes of GABAARs, the δ subunit containing GABAARs (δ-GABAARs), is predominantly expressed and located in extrasynaptic or perisynaptic positions. δ-GABAARs mediate a slow constant inhibitory current called tonic inhibition. While δ-GABAARs and tonic inhibition is critical for the excitability of single neurons, accumulating data suggest that the function of δ-GABAARs are broader and includes an integrative role in the network oscillations. While these open new horizons on the neurobiology of δ-GABAARs, the complexity continues to challenge the analysis of GABAARs and their subtypes. This review will summarize the current knowledge of molecular, cellular and physiological characteristics of δ-GABAARs during health and disease.


Asunto(s)
Hipocampo/fisiología , Inhibición Neural/fisiología , Receptores de GABA-A/fisiología , Animales , Hipocampo/metabolismo , Humanos , Receptores de GABA-A/metabolismo
11.
Adv Exp Med Biol ; 1192: 159-195, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31705495

RESUMEN

This chapter presents an overview of accumulating neuroimaging data with emphasis on translational potential. The subject will be described in the context of three disease states, i.e., schizophrenia, bipolar disorder, and major depressive disorder, and for three clinical goals, i.e., disease risk assessment, subtyping, and treatment decision.


Asunto(s)
Trastorno Bipolar/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Trastorno Depresivo Mayor/diagnóstico por imagen , Neuroimagen , Psiquiatría , Esquizofrenia/diagnóstico por imagen , Biomarcadores , Toma de Decisiones Clínicas , Humanos , Imagen por Resonancia Magnética , Medición de Riesgo
12.
J Integr Neurosci ; 18(4): 341-350, 2019 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-31912692

RESUMEN

The γ-Aminobutyric acid type A receptors (GABAARs) are heteropentameric chloride channels responsible for primary inhibition in the mammalian brain. Studies have shown the expression of recombinant GABAAR subunits tagged with the green fluorescent protein (GFP), a 26.9 kDa protein that exhibits bright green fluorescence when exposed to light in the blue to ultraviolet range. This allows the formation of recombinant proteins essential for the development of relevant in-vitro and in-vivo methodologies. Among the GABAAR subunits, the δ subunit was never tagged in its cytoplasmic domain, an evolutionary conserved domain found in between the third and the fourth transmembrane domains. In this study, first, we have cloned the mouse cDNAs encoding for the δ, α1, ß2 subunits of GABAARs, and then developed two fusion proteins of δ subunit each tagged with the GFP variant, EGFP (enhanced GFP) at unique sites in the cytoplasmic domain. The recombinant proteins were expressed alone or in combination with α1 and/or ß2 subunits in neuroblastoma 2a cells. Live cell confocal microscopy indicated that the cytoplasmically tagged δ subunits were targeted to the cell membrane when expressed in the presence of α1 and ß2 subunits in neuroblastoma 2a cells. However, this was not observed when they were expressed alone or only with α1 or ß2 subunits in the same cell line. These results confirm the general oligomerization and targeting pattern of GABAAR subtypes described in the other in-vitro studies in the literature. Thus, our results suggest that the EGFP tagging in the ctoplasmic domain did not interfere with the oligomerization and cell surface expression of recombinant δ subunits. To our knowledge, this is the first study showing the generation, expression and preliminary analysis of the δ-GABAARs tagged in the cytoplasmic domain of the δ subunit which can be further elaborated to probe intracellular protein interactions of GABAARs via the δ subunit.


Asunto(s)
Membrana Celular/metabolismo , Receptores de Canales Iónicos con Asa de Cisteína Activados por Ligando/metabolismo , ADN Complementario/metabolismo , Receptores de GABA-A/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Animales , Línea Celular Tumoral , Proteínas Fluorescentes Verdes , Ratones , Ratones Endogámicos C57BL , Microscopía Confocal , Imagen Óptica
13.
Int J Mol Sci ; 19(1)2018 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-29324666

RESUMEN

Schizophrenia (SZ) is a heritable brain disease originating from a complex interaction of genetic and environmental factors. The genes underpinning the neurobiology of SZ are largely unknown but recent data suggest strong evidence for genetic variations, such as single nucleotide polymorphisms, making the brain vulnerable to the risk of SZ. Structural and functional brain mapping of these genetic variations are essential for the development of agents and tools for better diagnosis, treatment and prevention of SZ. Addressing this, neuroimaging methods in combination with genetic analysis have been increasingly used for almost 20 years. So-called imaging genetics, the opportunities of this approach along with its limitations for SZ research will be outlined in this invited paper. While the problems such as reproducibility, genetic effect size, specificity and sensitivity exist, opportunities such as multivariate analysis, development of multisite consortia for large-scale data collection, emergence of non-candidate gene (hypothesis-free) approach of neuroimaging genetics are likely to contribute to a rapid progress for gene discovery besides to gene validation studies that are related to SZ.


Asunto(s)
Mapeo Encefálico/métodos , Estudio de Asociación del Genoma Completo/métodos , Esquizofrenia/genética , Animales , Humanos , Imagen por Resonancia Magnética/métodos , Polimorfismo de Nucleótido Simple , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatología
14.
Prog Neuropsychopharmacol Biol Psychiatry ; 80(Pt B): 155-165, 2018 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-28645536

RESUMEN

Imaging genetics is a research methodology studying the effect of genetic variation on brain structure, function, behavior, and risk for psychopathology. Since the early 2000s, imaging genetics has been increasingly used in the research of schizophrenia (SZ). SZ is a severe mental disorder with no precise knowledge of its underlying neurobiology, however, new genetic and neurobiological data generate a climate for new avenues. The accumulating data of genome wide association studies (GWAS) continuously decode SZ risk genes. Global neuroimaging consortia produce collections of brain phenotypes from tens of thousands of people. In this context, imaging genetics will be strategically important both for the validation and discovery of SZ related findings. Thus, the study of GWAS supported risk variants as candidate genes to validate by neuroimaging is one trend. The study of epigenetic differences in relation to variations of brain phenotypes and the study of large scale multivariate analysis of genome wide and brain wide associations are other trends. While these studies hold a big potential for understanding the neurobiology of SZ, the problem of reproducibility appears as a major challenge, which requires standardizations in study designs and compensations of methodological limitations such as sensitivity and specificity. On the other hand, advancements of neuroimaging, optical and electron microscopy along with the use of genetically encoded fluorescent probes and robust statistical approaches will not only catalyze integrative methodologies but also will help better design the imaging genetics studies. In this invited paper, I will discuss the current perspective of imaging genetics and emerging opportunities of SZ research.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Biología Molecular , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/genética , Encéfalo/diagnóstico por imagen , Humanos
15.
Int. j. morphol ; 34(1): 189-196, Mar. 2016. ilus
Artículo en Inglés | LILACS | ID: lil-780493

RESUMEN

This study reports tympanic cavity (TC) volume in newborns, which was missing in the literature. Ex vivo histology and computerized tomography (CT) scans were performed on temporal bone and data were analyzed in part using software developed in house. CT images with a slice thickness of 0.5 mm were obtained from 5 newborn cadavers and analyzed independently by two expert researchers. The border of the TC was delineated manually and measurement of area of interest was calculated on masked images. Then, the area measurements from all sections were added to estimate the total volume. The agreements between the histological and CT findings were then compared for accuracy, repeatability and reliability. The Dice and Jaccard similarity coefficient measures were used as a statistical validation metric to evaluate the assessor's performance in manual volume segmentation. Good assessor agreement was observed with average Dice values above 0.8 indicating that consistent and reliable volume measurements were feasible. The proposed protocol was shown to be accurate in calculating the TC volume, and thus can be used for computer-assisted presurgical planning or for diagnosing structural alterations in TC.


El objetivo fue determinar el volumen de la cavidad timpánica (CT) en recién nacidos, información no encontrada en la literatura. Se realizaron escaners a través de tomografia computadorizada (TC) y estudios histológicos en el hueso temporal; los datos se analizaron utilizando un software desarrollado en nuestra institución. Se obtuvieron imágenes de secciones de TC, de 0,5 mm de grosor, a partir de 5 cadáveres de recién nacidos, los que fueron analizados de forma independiente por dos investigadores expertos. El margen de los cortes de TC fue delineado manualmente y la medición del área de interés se estimó sobre imágenes ocultas. Después, se añadieron las mediciones de área de todas las secciones para estimar el volumen total. Las concordancias entre el estudio histológico y los hallazgos de la TC se compararon en cuanto a precisión, repetibilidad y confiabilidad. Se utilizaron las medidas de coeficiente de similitud de Jaccard y Dice como métrica de validación estadística para evaluar el desempeño del asesor en la medición manual del volumen. Se observó una buena correlación del evaluador con los valores medios de Dice, por encima de 0,8 indicando que es factible obtener mediciones coherentes y confiables de volumen. El protocolo propuesto ha demostrado ser preciso para calcular el volumen de la CT, y por lo tanto se puede utilizar para la planificación prequirúrgica asistida o para el diagnóstico de alteraciones estructurales en la CT.


Asunto(s)
Humanos , Recién Nacido , Oído Medio/anatomía & histología , Oído Medio/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Cadáver
16.
J Neuropsychiatry Clin Neurosci ; 27(2): 81-92, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25751509

RESUMEN

The majority of neuropsychiatric disorders show a strong degree of heritability, yet little is known about molecular factors involved in the pathophysiology of diseases like schizophrenia. After a brief historical introduction into the current understanding of neuropsychiatric disorders, the aim of this study is to discuss imaging genetics as a strategy to explore the pathophysiology of neuropsychiatric disorders. The candidate gene approach of imaging genetics is used for validation/replication studies of genes, whereas the hypothesis-free, noncandidate gene approach appears to be a tool for gene discovery. Besides, integration of environmental factors into neuroimaging begins to converge on neuroimaging studies of genetic variation. In the light of data from other avenues such as animal experimentation, these developments show a model of interdisciplinary research, which may lead to identifying markers for neuropsychiatric disorders.


Asunto(s)
Conducta/fisiología , Encéfalo/patología , Predisposición Genética a la Enfermedad/genética , Trastornos Mentales , Animales , Endofenotipos , Interacción Gen-Ambiente , Estudios de Asociación Genética , Humanos , Trastornos Mentales/genética , Trastornos Mentales/patología , Trastornos Mentales/psicología , Neuroimagen
17.
J Integr Neurosci ; 13(4): 617-31, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25233879

RESUMEN

GABA(A) receptors (GABA(A)Rs) are hetero-pentameric chloride channels and the primary sites for fast synaptic inhibition. We have expressed recombinant γ2 and δ subunits of GABA(A)Rs in cultured hippocampal neurons to analyze the membrane targeting of synaptic and extra-synaptic GABA(A)Rs, a phenomenon not well understood. Our data demonstrate that the synaptic targeting of γ2-containing GABA(A)Rs (γ2-GABA(A)Rs) does not depend on the cytoplasmic loop of γ2 subunit, in parallel with previous findings, showing that the synaptic localization of γ2-GABA(A)Rs requires the TM4 domain of γ2 rather than the large cytoplasmic loop. On the other hand, we showed here that the extrasynaptic targeting of the δ-containing GABA(A)Rs (δ-GABA(A)Rs) depends on the cytoplasmic loop of δ subunit via an active or a passive mechanism. We also show that the amino acid sequences of δ loop is highly conserved across the whole span of vertebrate evolution suggesting an active role of δ loop in extra-synaptic targeting of corresponding receptor subtypes.


Asunto(s)
Citoplasma/metabolismo , Neuronas/citología , Receptores de GABA-A/metabolismo , Sinapsis/metabolismo , Animales , Células Cultivadas , Citoplasma/genética , Embrión de Mamíferos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Hipocampo/citología , Ratones , Modelos Moleculares , Estructura Terciaria de Proteína , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Transporte de Proteínas/fisiología , Receptores de GABA-A/genética , Transfección
18.
Water Sci Technol ; 62(10): 2286-93, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21076214

RESUMEN

Sulfide is present in wastewaters as well as in biogas and can be removed by several physicochemical and biotechnological processes. Nitrate is a potential electron acceptor, readily available in most wastewater treatment plants and it can replace oxygen under anoxic conditions. A lab-scale reactor was operated for treatment of sulfide containing wastewater with nitrate as an electron acceptor and is used to evaluate the effects of volumetric loading rates, hydraulic retention time (HRT) and substrate concentrations on the performance of the lithotrophic denitrification process for treating industrial fermentation wastewaters. Sulfide is removed more than 90% at the loading rates between 0.055 and 2.004 kg S(-2)/m(3) d, when the influent sulfide concentration is kept around 0.163 kg/m(3) and the HRT decreased from 86.4 to 2 h. Nitrogen removal differed between 23 and 99% with different influent NO(3)(-)-N concentration and loading rates of NO(3)(-)/S(-2) ratio. The stoichiometry of sulfide oxidation with nitrate is calculated assuming different end-products based on thermodynamic approach and compared with experimental yield values. The calculated maximum volumetric and specific sulfide oxidation rates reached 0.076 kg S(-2)/m(3) h and 0.11 kg S(-2)/kg VSS h, respectively. The results are obtained at industrially relevant conditions and can be easily adapted to either biogas cleaning process or to sulfide containing effluent streams.


Asunto(s)
Residuos Industriales/análisis , Nitratos/química , Sulfuros/química , Eliminación de Residuos Líquidos/métodos , Procesos Autotróficos , Reactores Biológicos , Electrones , Oxidación-Reducción , Aguas del Alcantarillado/química , Factores de Tiempo
19.
Environ Monit Assess ; 138(1-3): 191-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17566866

RESUMEN

We investigated conventional characterization of wastewaters of the "Kullar Domestic Wastewater Treatment Plant." In the study of conventional characterization; 23 composite samples, which were taken during 10 months, were used and analysed as COD, BOD5, TKN, NH3-N, SS, VSS, TP, RP, TS, Alkalinity, oil and grease, detergent, chloride parameters. For determine of the plant efficiency, 8 output grab samples were taken. The COD and BOD5 values of influent, respectively, ranging from 37 to 1,056 mg/L and 8 to 140 mg/L in total wastewater. The meanly BOD5/COD ratio was calculated as 0.34 in total wastewaters.


Asunto(s)
Aguas del Alcantarillado/análisis , Eliminación de Residuos Líquidos , Contaminantes del Agua/análisis , Amoníaco/análisis , Monitoreo del Ambiente , Nitrógeno/análisis , Fósforo/análisis , Turquía
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