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1.
Anal Chem ; 95(37): 13941-13948, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37653711

RESUMO

Isoelectric focusing (IEF) is a powerful tool for resolving complex protein samples, which generates IEF patterns consisting of multiplex analyte bands. However, the interpretation of IEF patterns requires the careful selection of isoelectric point (pI) markers for profiling the pH gradient and a trivial process of pI labeling, resulting in low IEF efficiency. Here, we for the first time proposed a marker-free IEF method for the efficient and accurate classification of IEF patterns by using a convolutional neural network (CNN) model. To verify our method, we identified 21 meat samples whose IEF patterns comprised different bands of meat hemoglobin, myoglobin, and their oxygen-binding variants but no pI marker. Thanks to the high throughput and short assay time of the microstrip IEF, we efficiently collected 1449 IEF patterns to construct the data set for model training. Despite the absence of pI markers, we experimentally introduced the severe pH gradient drift into 189 IEF patterns in the data set, thereby omitting the need for profiling the pH gradient. To enhance the model robustness, we further employed data augmentation during the model training to mimic pH gradient drift. With the advantages of simple preprocessing, a rapid inference of 50 ms, and a high accuracy of 97.1%, the CNN model outperformed the traditional algorithm for simultaneously identifying meat species and cuts of meat of 105 IEF patterns, suggesting its great potential of being combined with microstrip IEF for large-scale IEF analyses of complicated protein samples.


Assuntos
Aprendizado Profundo , Focalização Isoelétrica , Ponto Isoelétrico , Algoritmos , Carne
2.
Mol Cell Biochem ; 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37594629

RESUMO

Looking at the development status of Nigeria and other developing nations, most low-income and rural households often use coal as a source of energy which necessitates its trade very close to the communities. Moreover, the effects of exposure to coal mining activities are rarely explored or yet to be studied, not to mention the numerous street coal vendors in Nigeria. This study investigated the oxidative stress levels in serum and urine through the biomarker 8-OHdG and DNA damage via single cell gel electrophoresis (alkaline comet assay). Blood and urine levels of 8-OHdG from 130 coal vendors and 130 population-based controls were determined by ELISA. Alkaline comet assay was also performed on white blood cells for DNA damage. The average values of 8-OHdG in serum and urine of coal vendors were 22.82 and 16.03 ng/ml respectively, which were significantly greater than those detected in controls (p < 0.001; 15.46 and 10.40 ng/ml of 8-OHdG in serum and urine respectively). The average tail length, % DNA in tail and olive tail moment were 25.06 µm, 18.71% and 4.42 respectively for coal vendors. However, for controls, the average values were 4.72 µm, 3.63% and 1.50 for tail length, % DNA in tail and olive tail moment respectively which were much lower than coal vendors (p < 0.001). Therefore, prolonged exposure to coal dusts could lead to higher serum and urinary 8-OHdG and significant DNA damage in coal vendors observed in tail length, % DNA in tail, and olive tail moment by single cell gel electrophoresis. It is therefore established that coal vendors exhibit a huge risk from oxidative stress and assessment of 8-OHdG with single cell gel electrophoresis has proven to be a feasible tool as biomarkers of DNA damage.

3.
Saudi Pharm J ; 31(12): 101832, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125951

RESUMO

In the current work, cytotoxicity and genotoxicity of different organoselenium compounds were examined using Trypan blue exclusion and alkaline comet assays with silver staining respectively. Leukocytes were subjected to a 3-hour incubation with organoselenium compounds at concentrations of 1, 5, 10, 25, 50, and 75 µM, or with the control vehicle (DMSO), at a temperature of 37 °C. The viability of the cells was evaluated using the Trypan blue exclusion method, while DNA damage was analyzed through the alkaline comet assay with silver staining. The exposure of leukocytes to different organoselenium compounds including i.e. (Z)-N-(pyridin-2-ylmethylene)-1-(2-((2-(1-((E)-pyridin-2-ylmethyleneamino)ethyl)phenyl)diselanyl)phenyl)ethanamine (C1), 2,2'(1Z,1'E)-(1,1'-(2,2'-diselanediylbis(2,1-phenylene))bis(ethane-1,1-diyl)) bis(azan-1-yl-1-ylidene)bis -methan-1-yl-1-ylidene)diphenol (C2), and dinaphthyl diselenide (NapSe)2, At concentrations ranging from 1 to 5 µM, no significant DNA damage was observed, as indicated by the absence of a noteworthy increase in the Damage Index (DI). Our results suggest that the organoselenium selenium compounds tested were not genotoxic and cytotoxic to human leukocytes in vitro at lower concentration. This study offers further insights into the genotoxicity profile of these organochalcogens in human leukocytes. Their genotoxicity and cytotoxicity effects at higher concentration are probably mediated through reactive oxygen species generation and their ability to catalyze thiol oxidation.

4.
Pak J Med Sci ; 38(4Part-II): 888-892, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634589

RESUMO

Background & Objectives: Traumatic Spinal cord injury (SCI) is a devastating condition that results in life long disability. Impairments associated with traumatic SCI such as sensory, motor, and autonomic dysfunctions lead to an array of secondary SCI-specific complications. Neuropathic pain is one of the most common medical complications of traumatic SCI which significantly affects motor function and activities of daily living (ADL) in people with traumatic SCI. Neuropathic pain is one of the main factors for dependency, decreased quality of life (QOL), poor rehabilitation outcomes, and depression in traumatic SCI individuals. The main aim of the current study was to determine the frequency of neuropathic pain and its effects on rehabilitation outcomes, balance function, and QOL in people with traumatic SCI. Methods: A cross-sectional survey was carried out at PCP from March to August 2020. Overall, 123 participants were added to the study using a non-probability convenience sampling technique. Information was collected using an adapted, validated questionnaire. Both male and female traumatic SCI patients with age between 18-60 years who received at least two weeks of rehabilitation, 42 days after diagnosis of traumatic SCI were included in current study while patients with Acute SCI, SCI patients with any other condition which can affect neuropathic pain such as traumatic brain injury, diabetic neuropathy, amputation, etc. and progressive neurological diseases such as multiple sclerosis and Guillain barre syndromes were excluded. Patients who have received at least two weeks of rehabilitation, 42 days after diagnosis of traumatic SCI. Patients with traumatic SCI. Results: Overall, 123 traumatic SCI patients were included in the study. The majority of the (n=101, 82%) participants were male and 83 (67.5%) were from urban areas. Eighty-Seven (70.73%) participants had neuropathic pain. Neuropathic pain was significantly associated (P-value <0.005) with rehabilitation outcomes, balance function, and quality of life. Conclusion: It can be concluded that more than two-third of SCI patients suffer from neuropathic pain. Moreover, neuropathic pain is significantly associated with rehabilitation outcomes, balance function, and quality of life.

5.
Water Sci Technol ; 83(7): 1739-1752, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33843756

RESUMO

An exceedingly facile green approach that produces a reliable adsorbent based on a transition metal such as Iron (Fe) using Mangifera indica leaf extract at room temperature is described. A single pot method was used for synthesis with no capping agents, surfactants or other templates. The main intention of this study is to synthesize iron nanoparticles from leaf extract (Mangifera indica) and examine its degradation potential for photo-catalytic removal of dyes (Congo red and brilliant green) from wastewater. Characterization of synthesized nanoparticles was executed by pHpzc, scanning electron microscopy and Fourier transform infrared spectroscopy studies and results confirm the presence of iron nano-sheets with biomolecules. All photo-catalytic experimental results were assessed by sum of squared estimate of errors and simple linear regression R2 with dye concentration, pH, contact time and dose rate as dependent and independent variables. Adsorption experimental data was verified by kinetics and isothermal models. Results showed that Langmuir and pseudo second order models give best fitness towards the photo-catalytic adsorption procedure. Thermodynamics revealed that adsorption mechanism is endothermic, described by the values of changes in Gibbs free energy, enthalpy and entropy, and is chemisorption in nature, with spontaneous processes. Overall photo-catalytic adsorption execution with synthesized iron nanoparticles and simple biomass of Mangifera indica gives satisfactory results for treating dye wastewater.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Adsorção , Corantes , Concentração de Íons de Hidrogênio , Cinética , Mangifera , Extratos Vegetais , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
6.
J Pak Med Assoc ; 71(3): 966-976, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34057956

RESUMO

OBJECTIVE: The accreditation standards developed by the World Federation of Medical Education (WFME) are acknowledged as regulatory mechanism for quality assurance of medical education programmes. The scoping review was planned to collect all the literature for identification of the barriers affecting the implementation of quality curriculum defined by WFME. METHODS: The literature was searched in electronic databases for relevant peer-reviewed studies over the last ten years. The search terms used were, `challenges of WFME accreditation', `barriers to accreditation', `challenges to accreditation in healthcare system', `hindrances to WFME accreditation standards', and `barriers to WFME standards', in PubMed, ERIC, PsycINFO databases, and in Google Scholar for grey literature. After screening and assessing for eligibility, 922 publications were retrieved and only 19 articles were included in study. The QualSyst appraisal tool was used to appraise the quality of studies. Data was synthsized to present the findings. RESULTS: The themes identified after data synthesis broadly described the barriers to implementation in various domains of WFME standards. The themes were social and political support, process of curriculum development, involvement of students in curricular planning, organizational setup, infrastructure, technical issues/ management of curriculum. The social and political support referred to leadership and governance, a prime barrier to address. Similarly, organizational setup, infrastructure and technical issues should also be looked for apart from students and curriculum. CONCLUSIONS: The scoping review will inform and lay the foundation for more empirical studies on quality improvement in health professional education, particularly in low and middle-income countries.


Assuntos
Países em Desenvolvimento , Educação Médica , Acreditação , Currículo , Ocupações em Saúde , Humanos
7.
Electrophoresis ; 41(16-17): 1529-1538, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32529672

RESUMO

As an effective separation tool, free-flow electrophoresis has not been used for purification of low-abundance protein in complex sample matrix. Herein, lysozyme in complex egg white matrix was chosen as the model protein for demonstrating the purification of low-content peptide via an FFE coupled with gel fitration chromatography (GFC). The crude lysozyme in egg while was first separated via free-flow zone electrophoresis (FFZE). After that, the fractions with lysozyme activity were condensed via lyophilization. Thereafter, the condensed fractions were further purified via a GFC of Sephadex G50. In all of the experiments, a special poly(acrylamide- co-acrylic acid) (P(AM-co-AA)) gel electrophoresis and a mass spectrometry were used for identification of lysozyme. The conditions of FFZE were optimized as follows: 130 µL/min sample flow rate, 4.9 mL/min background buffer of 20 mM pH 5.5 Tris-Acetic acid, 350 V, and 14 °C as well as 2 mg/mL protein content of crude sample. It was found that the purified lysozyme had the purity of 80% and high activity as compared with its crude sample with only 1.4% content and undetectable activity. The recoveries in the first and second separative steps were 65% and 82%, respectively, and the total recovery was about 53.3%. The reasons of low recovery might be induced by diffusion of lysozyme out off P(AM-co-AA) gel and co-removing of high-abundance egg ovalbumin. All these results indicated FFE could be used as alternative tool for purification of target solute with low abundance.


Assuntos
Cromatografia em Gel/métodos , Clara de Ovo/química , Eletroforese/métodos , Muramidase/isolamento & purificação , Animais , Antibacterianos/análise , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Galinhas , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Muramidase/análise , Muramidase/química , Muramidase/farmacologia
8.
Pak J Med Sci ; 36(3): 310-315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32292425

RESUMO

OBJECTIVE: To determine the morphological variations and location of pterion in Pakistani male population. METHODS: This retrospective observational study was carried out in the Department of Radiology, Shifa International Hospital from December 2018 to June 2019. The sample size was calculated by Open Epi web-based calculator. Fifty-three cranial CT scans with slice thickness of 0.5mm; consecutive scans of males were randomly selected. The patients with no craniofacial fracture and ages from 25 to 45 years were included. The dataset was obtained from Toshiba Aquilion One, 360-slice MDCT. The images were imported into the imaging software PACS (WFM), and analyzed in maximum intensity projection mode with three dimensional multiplanar reconstruction viewers. Measurements were taken in lateral projections of skull in Frankfurt plane, as horizontal and vertical distance from the posterolateral margin of frontozygomatic suture to center of pterion. Vertical distance from the superior border of zygomaticotemporal arch to the center of pterion. The morphological types were also recognized. RESULTS: The type of pterion on right side was 94.3% sphenoparietal 5.6% epipteric whereas left side was (90.5%) sphenoparietal (3.7%) epipteric, (3.7%) stellate type, (1.8%) frontotemporal type. The mean horizontal and vertical frontozygomatic measurements on right side were 2.23 ± 0.22cm and 1.25±0.219 cm respectively. The same measurements on the left side were 2.27-±0.25 cm and 1.226-±0.22 cm respectively. The mean zygomaticotemporal measurements on the right and left sides were 3.45 ±0.29cm and 3.44 ±0.25 cm respectively. The mean distance on right and left side of skull was statistically insignificant. CONCLUSION: The study provides useful data for position and location of pterion for safe neurosurgical procedures via pterion. Moreover, the knowledge about different morphological types of pterion help the radiologist to differentiate between a fracture line and normal morphological variety.

9.
Anal Chem ; 91(12): 7500-7504, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31132248

RESUMO

Absolute quantification of ligand capped on the surface of nanoparticles (NPs) has faced a great challenge without the use of complex inner standards (CIS). Herein, we proposed a facile electrophoresis titration (ET) model, designed an ET device, and developed a relevant method for counting the ligand on NPs without the use of CIS, based on moving reaction boundary (MRB). Furthermore, we conducted the relevant ET runs by using 3-mercaptopropionic acid (MPA) and quantum dots (QDs) as the model ligand and NPs, respectively. The experiments revealed that the ligand content of 1518 ± 295 obtained via an ET was close to the one of 1408 ± 117 determined via NMR, validating the ET model. Moreover, the experiments showed fair stability (RSD < 5.62%) and simplicity of ET without the use of CIS. Evidently, the ET model opens a window for facile assay of ligand capped on NPs.

10.
Electrophoresis ; 40(20): 2767-2774, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31172555

RESUMO

A novel analytical protocol was developed for general quality screening of chicken meat based on IEF and protein extraction. To demonstrate the developed protocol, 24 chickens were divided into three groups; each had eight chickens. The chickens in Group 1 were slaughtered by exsanguination, Group 2 asphyxiated in water, and that in Group 3 were infected by new castle disease virus. Proteins were extracted from the meat samples by using pure water as an extractant, separated by IEF, verified by western blot, and quantified via imaging analysis. The relevant experiments demonstrated that two myoglobin (Mb) bands were detected at pI 6.8 and 7.04 for all samples of Groups 1, 2, and 3, but there were additional hemoglobin (Hb) bands at pI 7.09 and 7.13 (P < 0.05) for the samples of Groups 2 and 3. The results implied that Hb bands might be a potential biomarker for the screening of chicken meat quality. The RSD values of two Mb bands (pI 6.8 and 7.04) in Group 1 were respectively 4.08 and 3.63%, the ones of two Hb bands (pI 7.09 and 7.13) in Group 2 were 3.66 and 2.10%, and those in Group 3 were 2.17% and 2.77%, respectively. All the RSD values indicated high stability and reliability of the developed protocol. Additionally, the protocol had a direct readout of protein bands in IEF without staining. However, it was time-consuming and had high cost. Even so, the relevant general method and finding have potential for screening of chicken meat quality.


Assuntos
Hemoglobinas/análise , Focalização Isoelétrica/métodos , Carne/análise , Carne/normas , Mioglobina/análise , Animais , Biomarcadores , Western Blotting , Galinhas , Reprodutibilidade dos Testes
11.
BMC Complement Altern Med ; 19(1): 80, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30943970

RESUMO

BACKGROUND: Organochalcogen compounds have attracted the interest of a multitude of studies for their promising Pharmacological and biological activities. The antioxidant activity and acute toxicity of an organoselenium compound, 1-(2-(2-(2-(1-aminoethyl)phenyl)diselanyl)phenyl)ethanamine (APDP) was determined in mice. METHODS: Mice were randomly divided into four groups, with each group comprising of seven animals. Canola oil (1ml/kg of body weight) was administered to 1st group, while 2nd, 3rd & 4th groups were administered with 10 mg/kg, 30 mg/kg & 350 mg/kg of APDP respectively. APDP was administered by Intragastric gavage as a single oral dose. RESULTS: The APDP oral administration was found to be safe up to 350 mg/kg of body weight and no deaths of animals were recorded. The lethal dose 50 (LD50) for APDP was determined at 72 h and was estimated to be > 350 mg/kg. After acute treatment, all mice were sacrificed by decapitation to determine the antioxidant enzymes and lipid peroxidation values for the treated mice liver. No fluctuation in lipid peroxidation, vitamin C and non protein thiol (NPSH) levels was observed due to the administration of APDP. hepatic α-ALA-D activity, catalase (CAT), superoxide dismutase (SOD) and the biochemical parameters were evaluated. Experimental observation demonstrated that APDP protected Fe(II) induced thiobarbituric acid reactive substances (TBARS) production in liver homogenate significantly (p < 0.05). The administration of APDP (an amine-based diselenide) both in vitro and in vivo clearly demonstrated that this potential compound has no acute toxicity towards mice among all the tested parameter. CONCLUSION: On the basis of experimental results, it is concluded that APDP is a potential candidate as an antioxidant compound for studying pharmacological properties.


Assuntos
Compostos Organosselênicos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fenetilaminas/toxicidade , Administração Oral , Animais , Antioxidantes/análise , Dose Letal Mediana , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/química , Fígado/efeitos dos fármacos , Masculino , Camundongos , Compostos Organosselênicos/administração & dosagem , Fenetilaminas/administração & dosagem
12.
J Sci Food Agric ; 99(15): 6911-6921, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31393604

RESUMO

BACKGROUND: This study aimed to evaluate the possibility of cotton waste enrichment with glycine betaine (GB) for production of two strains (P9, P10) of king oyster (Pleurotus eryngii). Cotton waste was used as (100%) control (T0 = cotton waste) and augmented with various combinations of GB, (T1 = 2 mmol L-1 , T2 = 4 mmol L-1 , T3 = 6 mmol L-1 , T4 = 8 mmol L-1 and T5 = 10 mmol L-1 ). The response of king oyster to GB was evaluated by earliness, yield, biological efficiency (BE), minerals (nitrogen, phosphorus, potassium, zinc (Zn), copper (Cu), magnesium (Mg), manganese (Mn), iron (Fe), sodium (Na), calcium (Ca)), total sugars, total soluble solids, reducing sugars, non-reducing sugars, ascorbic acid, proximate (crude protein, carbohydrates, crude fibers, ash, fats) content of fruiting body and Fourier-transform infrared (FTIR) spectroscopy analysis compared with the control substrate (cotton waste). RESULTS: The earliness, yield, and BE were higher as compared to control substrate and increased with an augmentation in the concentration of GB within the cotton waste. Two strains showed (on dry weight basis) 33.9-54.9 mg g-1 nitrogen, 6.8-12.5 mg g-1 phosphorus, 16.9-25.1 mg g-1 potassium, 40.5-64.2 mg kg-1 Zn, 17.1-37.3 mg kg-1 Cu, 1174-1325 mg kg-1 Mg, 20.1-29.1 mg kg-1 Mn, 129-265 mg kg-1 Fe, 779-835 mg kg-1 Ca), 6.3%-11.3% total sugars, 7.3-14.9 °Brix total soluble solids, 2.1-7.3% reducing sugars, 10.4-18.1% crude protein, 3.6-4.4% crude fiber and 5.6-16.7 mg (100 g)-1 on various concentration of GB enrich cotton waste. Cotton waste enriched with GB significantly affected nutritional profile of king oyster mushroom. CONCLUSION: The results revealed that GB enriched cotton waste can be used as an innovative substrate to enhance the yield and quality of king oyster mushroom. © 2019 Society of Chemical Industry.


Assuntos
Betaína/metabolismo , Meios de Cultura/metabolismo , Glicina/metabolismo , Gossypium/microbiologia , Pleurotus/química , Pleurotus/metabolismo , Resíduos/análise , Betaína/análise , Meios de Cultura/química , Glicina/análise , Gossypium/metabolismo , Minerais/metabolismo , Nitrogênio/análise , Nitrogênio/metabolismo , Fósforo/análise , Fósforo/metabolismo , Pleurotus/genética , Pleurotus/crescimento & desenvolvimento
13.
Entropy (Basel) ; 21(3)2019 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33266955

RESUMO

In this article, the entropy generation characteristics of a laminar unsteady MHD boundary layer flow are analysed numerically for an incompressible, electrically conducting and dissipative fluid. The Ohmic heating and energy dissipation effects are added to the energy equation. The modelled dimensional transport equations are altered into dimensionless self-similar partial differential equations (PDEs) through suitable transformations. The reduced momentum and energy equations are then worked out numerically by employing a new hybrid method called the Gear-Generalized Differential Quadrature Method (GGDQM). The obtained numerical results are incorporated in the calculation of the Bejan number and dimensionless entropy generation. Quantities of physical interest, like velocity, temperature, shear stress and heat transfer rate, are illustrated graphically as well as in tabular form. Impacts of involved parameters are examined and discussed thoroughly in this investigation. Exact and GGDQM solutions are compared for special cases of initial unsteady flow and final steady state flow. Furthermore, a good harmony is observed between the results of GGDQM and those given previously by the Spectral Relaxation Method (SRM), Spectral Quasilinearization Method (SQLM) and Spectral Perturbation Method (SPM).

14.
Anal Chem ; 90(11): 6710-6717, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29696971

RESUMO

Melamine was sometimes adulterated to dairy products for false protein content increase in developing countries. However, a portable sensor has not been developed for on-spot determination of melamine in dairy products yet. Herein, a distance-based sensor was advanced for the quantification of melamine in dairy products based on chip electrophoretic titration (ET) of moving neutralization boundary (NB) and EDTA photocatalysis. In the chip sensor, EDTA, H2O2, and leucomalachite green (LMG) were added in the anode well. Under UV light, EDTA photocatalyzes H2O2 and colorless LMG as H2O and color malachite green (MG) with one positive charge. When applying an electric field, the MG in the anode well migrated into the channel and was neutralized with the base in the channel, resulting in colorless MG-OH and NB. If the melamine-content dairy sample was added into the EDTA-H2O2-LMG system, H2O2 reacts with melamine, leading to the decrease of MG. Thus, the higher the melamine content in dairy products, the shorter the distance of NB migration under the given time, implying a distance-based sensor of melamine. A series of experiments manifested the validity of ET-NB sensor for detection of melamine. Moreover, the results revealed the numerous merits of ET-NB sensor, such as good selectivity, high sensitivity (LOD down to 0.20 µM for milk and 0.10 µM for infant formula vs the FDA safety limits of 20 µM for milk and 8.0 µM for infant formula), good repeatability and recoveries (87-108% for milk, 90-107% for formula). Particularly, the cell phone-like sensor was portable, simple (no any pretreatment), rapid (within 15 min), as well as low cost, to evaluate the quality of dairy products. The developed sensor has great potential in on-spot detection of melamine in dairy products as well as other analytes, at which we are testing in our lab.


Assuntos
Laticínios/análise , Ácido Edético/química , Triazinas/análise , Catálise , Eletroforese Capilar , Peróxido de Hidrogênio/química , Técnicas Analíticas Microfluídicas , Estrutura Molecular , Processos Fotoquímicos , Corantes de Rosanilina/química
15.
Entropy (Basel) ; 20(8)2018 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-33265704

RESUMO

In this article, we investigated entropy generation and heat transfer analysis in a viscous flow induced by a horizontally moving Riga plate in the presence of strong suction. The viscosity and thermal conductivity of the fluid are taken to be temperature dependent. The frictional heating function and non-linear radiation terms are also incorporated in the entropy generation and energy equation. The partial differential equations which model the flow are converted into dimensionless form by using proper transformations. Further, the dimensionless equations are reduced by imposing the conditions of strong suction. Numerical solutions are obtained using MATLAB boundary value solver bvp4c and used to evaluate the entropy generation number. The influences of physical flow parameters arise in the mathematical modeling are demonstrated through various graphs. The analysis reveals that velocity decays whereas entropy generation increases with rising values of variable viscosity parameter. Furthermore, entropy generation decays with increasing variable thermal conductivity parameter.

16.
Entropy (Basel) ; 20(9)2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-33265757

RESUMO

The present research work explores the effects of suction/injection and viscous dissipation on entropy generation in the boundary layer flow of a hybrid nanofluid (Cu-Al2O3-H2O) over a nonlinear radially stretching porous disk. The energy dissipation function is added in the energy equation in order to incorporate the effects of viscous dissipation. The Tiwari and Das model is used in this work. The flow, heat transfer, and entropy generation analysis have been performed using a modified form of the Maxwell Garnett (MG) and Brinkman nanofluid model for effective thermal conductivity and dynamic viscosity, respectively. Suitable transformations are utilized to obtain a set of self-similar ordinary differential equations. Numerical solutions are obtained using shooting and bvp4c Matlab solver. The comparison of solutions shows excellent agreement. To examine the effects of principal flow parameters like suction/injection, the Eckert number, and solid volume fraction, different graphs are plotted and discussed. It is concluded that entropy generation inside the boundary layer of a hybrid nanofluid is high compared to a convectional nanofluid.

17.
Entropy (Basel) ; 20(12)2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33266667

RESUMO

The effects of variable thermal conductivity on heat transfer and entropy generation in a flow over a curved surface are investigated in the present study. In addition, the effects of energy dissipation and Ohmic heating are also incorporated in the modelling of the energy equation. Appropriate transformations are used to develop the self-similar equations from the governing equations of momentum and energy. The resulting self-similar equations are then solved by the Generalized Differential Quadrature Method (GDQM). For the validation and precision of the developed numerical solution, the resulting equations are also solved numerically using the Runge-Kutta-Fehlberg method (RKFM). An excellent agreement is found between the numerical results of the two methods. To examine the impacts of emerging physical parameters on velocity, temperature distribution and entropy generation, the numerical results are plotted against the various values of physical flow parameters and discussed physically in detail.

18.
Microb Pathog ; 110: 262-274, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28688981

RESUMO

The various aspects of MDR-TB, type of pathogen, different drug sensitive methods and mutation (s) in specific genes were determined. The histone-like protein (hupB) gene of M. tuberculosis was targeted by using primer sets: N & S and M & S (produced 645 bp & 318 bp fragment respectively). The most significant risk factors were the poverty and male gender of ages 11-25 years. All samples were detected as M. tuberculosis. By Drug Proportion method, the highest percentage (37%) was found resistant to only Rifampin. By MGIT method, the highest percentage (82.2%) was found resistant with the triple combination (Rifampin-RIF + Isoniazid-INH + Ethambutol-EMB) of the drugs. The highest mutations (76.92%) were found in gene rpoB (codon 531) in MDR TB patients. By, MAS-PCR, the highest percentage (34%) were found resistant to combination (INH + RIF) of the drugs. Minimum samples were resistant to RIF and RIF + INH drugs by MGIT, while proportionate results were observed from MAS-PCR and DP. Moreover, by MAS-PCR mutation in gene embB (306) caused EMB resistance (51.64%). We found that M. tuberculosis was the main cause of MDR-TB. Our findings may further be used for an early diagnosis of multi-drug resistant tuberculosis.


Assuntos
Etambutol/farmacologia , Isoniazida/farmacologia , Mycobacterium bovis/genética , Mycobacterium tuberculosis/genética , Patologia Molecular , Rifampina/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Adolescente , Adulto , Idoso , Proteínas de Bactérias/genética , Criança , DNA Bacteriano/genética , RNA Polimerases Dirigidas por DNA/genética , Genes Bacterianos , Histonas/genética , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem Molecular/métodos , Mutação , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium bovis/isolamento & purificação , Mycobacterium bovis/patogenicidade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Mycobacterium tuberculosis/patogenicidade , Paquistão , Pentosiltransferases/genética , Fatores de Risco , Tuberculose Resistente a Múltiplos Medicamentos/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adulto Jovem
19.
Ergonomics ; 60(8): 1064-1073, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27780437

RESUMO

Whole body vibration is a significant physical risk factor associated with low back pain. This study assessed farmers' exposure to whole body vibration on the Canadian prairies according to ISO 2631-1. Eighty-seven vibration measurements were collected with a triaxial accelerometer embedded in a rubber seat pad at the operator-seat interface of agricultural machinery, including tractors, combines, pickup trucks, grain trucks, sprayers, swathers, all-terrain vehicles, and skid steers. Whole body vibration was highest in the vertical axis, with a mean (range) frequency-weighted root mean squared acceleration of 0.43 m/s2 (0.19-1.06 m/s2). Mean crest factors exceeded 9 in all 3 axes, indicating high mechanical shock content. The vertical axis vibration dose value was 7.55 m/s1.75 (2.18-37.59 m/s1.75), with 41.4% of measurements within or above the health guidance caution zone. These high exposures in addition to an ageing agricultural workforce may increase health risks even further, particularly for the low back. Practitioner Summary: Agricultural workers are frequently exposed to whole body vibration while operating farm equipment, presenting a substantial risk to musculoskeletal health including the low back. Assessing vibration exposure is critical in promoting a safe occupational environment, and may inform interventions to reduce farmer's exposure to vibration.


Assuntos
Fazendeiros , Exposição Ocupacional/análise , Vibração , Acelerometria , Adulto , Doenças dos Trabalhadores Agrícolas/etiologia , Canadá , Pradaria , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Saskatchewan , Análise e Desempenho de Tarefas
20.
J Pak Med Assoc ; 67(7): 1045-1049, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28770884

RESUMO

OBJECTIVE: To determine the outcome of application of amniotic graft in ocular surface disorders. METHODS: This cross-sectional study was conducted at Dow University of Health Sciences, Karachi, from January 2010 to December 2012, and comprised patients with ocular surface disorders. Patients' presenting symptoms and signs were recorded. Previously harvested and frozen amniotic graft was applied in different types of ocular surface disorders, such as corneal ulcers, pterygium, keratomalacia, Steven-Johnson syndrome, etc. Following the surgery, patients were assessed for improvement in symptoms and signs related to epithelialisation in corneal ulcers.. RESULTS: Of the 50 patients, 30(60%) were male and 20(40%) female. The overall mean age was 40±19.3 years (range: 9 months to 80 years). Out of the 18(36%) cases of pterygium, there was recurrence in 5(27.7%) cases. There were 26(52%) patients of corneal ulcers, of whom re-epithelialisation occurred in 21(80.7%) patients. CONCLUSIONS: Amniotic membrane grafting was found to be a safe procedure for ocular surface disorders.


Assuntos
Âmnio/transplante , Doenças da Túnica Conjuntiva/cirurgia , Doenças da Córnea/cirurgia , Doenças da Esclera/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Úlcera da Córnea/cirurgia , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos , Paquistão , Pterígio/cirurgia , Reepitelização , Síndrome de Stevens-Johnson/cirurgia , Resultado do Tratamento , Deficiência de Vitamina A/cirurgia , Adulto Jovem
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