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1.
Environ Sci Pollut Res Int ; 30(28): 71714-71725, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34318426

RESUMO

This present investigation emphasizes on pros and cons of humic acid (HA) on electrosorption behaviour and performance efficiency of capacitive deionization (CDI) process. Electrosorptive removal of HA was examined by lab scale CDI flow cell under 100 ppm Na2SO4 as a supporting electrolyte. In addition, the electrosorption capacitance and desalination performances were also evaluated through cyclic voltammetry studies. In this perspective, we employed the carbon-based electrodes such as chemically treated activated carbon cloth (ACC), carbon aerogel electrodes grade-I (CA-I) and carbon aerogel electrode grade-II (CA-II) with active surface area for 1 cm2 and 24 cm2 respectively. The specific capacitance values of 30, 23 and 10 F g-1 were achieved for ACC, CA-1 and CA-II with 100 ppm Na2SO4 and 10 ppm HA electrolyte solution. The experimental results substantiated that ACC electrode exhibited higher removal efficiency compared to other two carbon electrodes (CA-I and CA-II). Eventually, the electrosorption removal of natural organic matter HA was observed as 15% for CA-I, 30% for CA-II and 58% for ACC electrodes in a CDI flow cell.


Assuntos
Substâncias Húmicas , Purificação da Água , Sódio , Cloreto de Sódio , Íons , Carvão Vegetal , Eletrodos , Purificação da Água/métodos
2.
Health Phys ; 119(1): 52-58, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32483043

RESUMO

The objective of this study was to establish radiation dose-response calibration curves using automated dicentric scoring to support rapid and accurate cytogenetic triage dose-assessment. Blood was drawn from healthy human volunteers and exposed to Co gamma rays at several dose rates (i.e., 1.0, 0.6, and 0.1 Gy min). After radiation, the blood was placed for 2 h in a 37 °C incubator for repair. Blood was then cultured in complete media to which a mitogen (i.e., phytoghemagglutinin, concentration 4%) was added for 48 h. Colcemid was added to the culture at a final concentration of 0.2 µg mL after 24 h for the purpose of arresting first-division metaphase mitotics. Cells were harvested at the end of 48 h. Samples were processed using an automated metaphase harvester and automated microscope metaphase finder equipped with a suite of software including a specialized automated dicentric scoring application. The data obtained were used to create dose-response tables of dicentric yields. The null hypothesis that the data is Poisson-distributed could not be rejected at the significance level of α = 0.05 using results from a Shiny R Studio application (goodness-of-fit Poisson). Calibration curves based on linear-quadratic fits for Co gamma rays at the three different dose rates were generated using these data. The calibration curves were used to detect blind test cases. In conclusion, using the automated harvester and automated microscope metaphase finder with associated automated dicentric scoring software demonstrates high-throughput with suitable accuracy for triage radiation dose assessment.


Assuntos
Radioisótopos de Cobalto/efeitos adversos , Raios gama/efeitos adversos , Exposição à Radiação/efeitos adversos , Triagem/métodos , Automação , Sangue/efeitos da radiação , Células Sanguíneas/efeitos da radiação , Calibragem , Aberrações Cromossômicas , Demecolcina/química , Relação Dose-Resposta à Radiação , Humanos , Mitógenos/química , Distribuição de Poisson , Doses de Radiação , Proteção Radiológica , Radiometria , Software , Fatores de Tempo
3.
J Voice ; 29(5): 603-10, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25795372

RESUMO

UNLABELLED: Vibrato, a small, nevertheless an important component in the singing voice is known to enrich the overall singing voice quality. However, in the perception of overall performance, it is often neglected. Singing performance is often appreciated by a mixed audience of those who love music, but not necessarily sing and other singers who may or may not be teachers of singing. OBJECTIVES: The objectives of the present study were aimed at investigating singers' and nonsingers' perception of vocal vibrato and its effect on the ratings of singer's overall performance. METHOD: Prerecorded audio samples of the chorus of a hymn (How Great Thou Art) as sung by 10 singers (both men and women) were played via a speaker to two groups of judges which consisted of three experienced singers and three experienced nonsingers. The singer judges (SJs) were vocal instructors in Western classical, music theater, pop, and contemporary styles. Seven parameters (presence of vibrato, rate, extent, conspicuousness, quality, periodicity, and type) related to vibrato were evaluated through auditory perception by these two groups of judges on a rating scale developed specifically for the study, and one parameter evaluated singer's overall performance. RESULTS: Cohen's Kappa statistical analysis was used for inter-rater reliability within groups. Nonsinger judges (NSJs) within the group showed varied ratings as did SJs, yet SJs did have higher agreement than NSJs. Chi-square analysis was used across groups. Both groups were distinct from each other in their perception of vibrato. Ratings of singer's overall performance were not affected for NSJs, but certainly affected for SJ. CONCLUSION: It could not be concluded that ratings on singer's overall performance was affected as a result of vibrato. Since vibrato is often over-ridden by the singer's voice. But a rare occasion can arise where a vibrato may not sound pleasant and can affect the listener's perception of the singer's performance. Often a feedback from listeners would help monitor singers' performance.


Assuntos
Percepção Auditiva , Ocupações , Canto , Qualidade da Voz , Estimulação Acústica , Feminino , Humanos , Julgamento , Percepção Sonora , Masculino , Variações Dependentes do Observador , Percepção da Altura Sonora , Prazer
4.
Artigo em Inglês | MEDLINE | ID: mdl-26520383

RESUMO

High-throughput individual diagnostic dose assessment is essential for medical management of radiation-exposed subjects after a mass casualty. Cytogenetic assays such as the Dicentric Chromosome Assay (DCA) are recognized as the gold standard by international regulatory authorities. DCA is a multi-step and multi-day bioassay. DCA, as described in the IAEA manual, can be used to assess dose up to 4-6 weeks post-exposure quite accurately but throughput is still a major issue and automation is very essential. The throughput is limited, both in terms of sample preparation as well as analysis of chromosome aberrations. Thus, there is a need to design and develop novel solutions that could utilize extensive laboratory automation for sample preparation, and bioinformatics approaches for chromosome-aberration analysis to overcome throughput issues. We have transitioned the bench-based cytogenetic DCA to a coherent process performing high-throughput automated biodosimetry for individual dose assessment ensuring quality control (QC) and quality assurance (QA) aspects in accordance with international harmonized protocols. A Laboratory Information Management System (LIMS) is designed, implemented and adapted to manage increased sample processing capacity, develop and maintain standard operating procedures (SOP) for robotic instruments, avoid data transcription errors during processing, and automate analysis of chromosome-aberrations using an image analysis platform. Our efforts described in this paper intend to bridge the current technological gaps and enhance the potential application of DCA for a dose-based stratification of subjects following a mass casualty. This paper describes one such potential integrated automated laboratory system and functional evolution of the classical DCA towards increasing critically needed throughput.


Assuntos
Automação Laboratorial/normas , Análise Citogenética/métodos , Ensaios de Triagem em Larga Escala/instrumentação , Radiometria/métodos , Aberrações Cromossômicas , Cromossomos Humanos/genética , Cromossomos Humanos/efeitos da radiação , Análise Citogenética/instrumentação , Ensaios de Triagem em Larga Escala/métodos , Humanos , Radiometria/instrumentação
5.
BMC Med Phys ; 9: 6, 2009 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-19531236

RESUMO

BACKGROUND: Radiation-induced chromosome aberrations lead to a plethora of detrimental effects at cellular level. Chromosome aberrations provide broad spectrum of information ranging from probability of malignant transformation to assessment of absorbed dose. Studies mapping differences in radiation sensitivities between human chromosomes are seldom undertaken. Consequently, health risk assessment based on radio-sensitivities of individual chromosomes may be erroneous. Our efforts in this article, attempt to demonstrate differences in radio-sensitivities of human chromosome-1 and/or -2, both in interphase and metaphase spreads. METHODS: Upon blood collection, dosimetry and irradiation were performed. Lymphocytes were isolated after whole-blood irradiation with 60Co gamma-rays in the dose range of 0-5 Gy for both interphase, and metaphase aberration studies. Induction of premature chromosome condensation in interphase cells was accomplished using a phosphatase inhibitor, calyculin-A. Metaphase spreads were harvested from short-term peripheral blood lymphocyte cultures following colcemid arrest and using an automated metaphase harvester and spreader. Aberration analysis in both interphase and metaphase spreads were done using FISH. RESULTS: In interphase, aberrant cell and aberration frequency involving chromosome 1 and/or 2 increased linearly with radiation dose. In metaphase, aberrations increased in a linear-quadratic manner with dose. Our studies ascertain that chromosome-2 is more radio-sensitive than chromosome-1 in both interphase and metaphase stages, albeit the DNA content of chromosome-2 is lesser than chromosome-1 by almost 10 million base pairs. CONCLUSION: Differences in radio-sensitivities of chromosomes have implications in genetic damage, chromosome organization, and chromosome function. Designing research experiments based on our vital findings may bring benefit to radiation-induced risk assessment, therapeutics and development of chromosome specific biomarkers.

6.
Pediatr Nephrol ; 17(8): 609-11, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12185466

RESUMO

A 10-week-old female infant developed hypertension. The elevated blood pressure was associated with metabolic alkalosis and urinary chloride wastage. The family history was unremarkable. Her urinalysis, blood urea nitrogen (BUN), and serum creatinine concentrations were all normal. A renal ultrasound was normal. A technetium-99m diethylenetriaminopentoacetic acid (DTPA) renal scan with captopril showed normal blood flow bilaterally. The head ultrasound and echocardiogram were normal. Blood epinephrine, norepinephrine, catecholamines, thyroxine, and steroid levels were also normal. Treatment with various combinations of labetalol, hydralazine, captopril, methyldopa, nifedipine, and spironolactone, all at high doses, failed to control the elevated blood pressure. Serum aldosterone level and peripheral plasma renin activity were low. The lack of therapeutic response to spironolactone, with a good response to amiloride and recurrence of hypertension and metabolic alkalosis after amiloride cessation that was subsequently treated with amiloride, established the diagnosis of Liddle syndrome. To our knowledge, this is the youngest patient with Liddle syndrome that has been reported in the literature.


Assuntos
Alcalose/patologia , Insuficiência de Crescimento/patologia , Hipertensão/patologia , Hipopotassemia/patologia , Nefropatias/patologia , Alcalose/tratamento farmacológico , Amilorida/uso terapêutico , Pressão Sanguínea/fisiologia , Diuréticos/uso terapêutico , Eletrólitos/metabolismo , Insuficiência de Crescimento/tratamento farmacológico , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipopotassemia/tratamento farmacológico , Recém-Nascido , Nefropatias/diagnóstico por imagem , Nefropatias/tratamento farmacológico , Testes de Função Renal , Compostos Radiofarmacêuticos/uso terapêutico , Espironolactona/uso terapêutico , Síndrome , Pentetato de Tecnécio Tc 99m/uso terapêutico , Ultrassonografia
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