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1.
J Cancer Res Ther ; 19(3): 793-800, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37470613

RESUMO

Aim: The present study was undertaken to evaluate the performance of different algorithms for flattening filter-free (FFF) and flattened (FF) photon beams in three different in-homogeneities. Materials and Method: Computed tomography (CT) image sets of the CIRS phantom maintained in the SAD setup by placing the ionization chamber in the lung, bone, and tissue regions, respectively, were acquired. The treatment planning system (TPS) calculated and the ionization chamber measured the doses at the center of the chamber (in the three mediums) were recorded for the flattened and non-flattened photon beams. Results: The results were reported for photon energies of 6 MV, 10 MV, 15 MV, 6 FFF, and 10 FFF of field sizes 5 × 5 cm2, 10 × 10 cm2, and 15 × 15 cm2. In the bone inhomogeneity, the pencil beam algorithm predicted that the maximum dose variation was 4.88% of measured chamber dose in 10-MV photon energy for the field size 10 × 10 cm2. In water inhomogeneity, both the collapsed cone and Monte Carlo algorithm predicted that the maximum dose variation was ± 3% of measured chamber dose in 10-MV photon energy for the field size 10 × 10 cm2 and in 10-MV FFF photon energy for the field size 5 × 5 cm2, whereas in lung inhomogeneity, the pencil beam algorithm predicted that the highest dose variation was - 6.9% of measured chamber dose in 10-MV FFF photon energy for the field size 5 × 5 cm2. Conclusion: FF and FFF beams performed differently in lung, water, and bone mediums. The assessment of algorithms was conducted using the anthropomorphic phantom; therefore, these findings may help in the selection of appropriate algorithms for particular clinical settings in radiation delivery.


Assuntos
Aceleradores de Partículas , Radiometria , Humanos , Dosagem Radioterapêutica , Mônaco , Radiometria/métodos , Fótons/uso terapêutico , Planejamento da Radioterapia Assistida por Computador/métodos , Imagens de Fantasmas , Água
2.
Sci Total Environ ; 872: 161960, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36739026

RESUMO

Nanostructured oxides and oxyhydroxides of iron are imperative constituents of the Earth's geological and biological processes i.e. biogeochemical cycles. So, the characteristic applications of iron oxide nanoparticles (FeONps) are closely linked to their surroundings and biological sinks. This work reports a low-cost green approach to promote 'waste-to-wealth' ideology by the direct and self-catalysis of iron rust into its nanoparticles (N-FeONps). A comparison is drawn based on the properties, morphologies, and applications after synthesizing FeONps by chemical precipitation method (C-FeONps). Spherical nanoparticles with vibrational properties are obtained in the size domain of 32 nm (N-FeONps) and 23 nm (C-FeONps). The application of Uniform deformation model, Uniform stress deformation model, Uniform deformation energy density model, and Size-strain plot models reveal comparatively greater defects in the crystal structures of C-FeONps. The biosafety profiling of natural and chemically designed nano-units performed on the species of bacteria, fungus, algae, and plants have shown enhanced safety terms associated with N-FeONps. The performance of N-FeONps has surpassed its chemical counterpart in medical applications such as antioxidant activity and anti-inflammatory activity with approximate percentages of 26 % and 51 % respectively. The findings of this piece of work favors the naturally obtained FeONps (N-FeONps), as they are economically viable, non-toxic, and have a greater antioxidant and anti-inflammatory arena. Hence, this waste-to-wealth ideology should be promoted for maintaining waste and designing solutions for the medical industries in one go.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Compostos Férricos/química , Monitoramento Biológico , Nanopartículas Metálicas/química , Ferro/química , Antioxidantes , Óxidos , Medição de Risco
3.
Biomed Phys Eng Express ; 8(2)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35144251

RESUMO

Purpose: In radiotherapy, accuracy in dose estimation of dose calculation methods is critical. The influence of deformity on radiation dose calculations derived by planning system is evaluated in present study. The goal of study was to create a low-cost inhomogeneous phantom for measuring absorbed dose using an Ionisation chamber and Gafchromic film, which was validated using treatment planning system (TPS) dose outcome.Methods:and Materials: The central axis dose calculations were computed using Pencil Beam Convolution algorithm (PBC), Collapsed Cone Convolution (CCC) and Monte Carlo (MC) algorithm in the Monaco treatment planning system using an In-house phantom (20 × 20 × 20cm3) made up of acrylic sheet containing water and inhomogeneous material wooden powder equivalent to lung. Phantom was scanned in Computed Tomography (CT) scanner and image set was sent to the planning workstation. The depth dose evaluations were performed using ionization chamber and Gafchromic film with same beam settings and monitor units in every setup. Following that, the calculated doses obtained from TPS and measured depth doses were compared.Results: The results was reported for photon energies 6MV, 10MV, 15MV, 6FFF and 10FFF at varying field sizes of 4 × 4 cm2, 5 × 5 cm2, 10 × 10 cm2, and 15 × 15 cm2. MC maximum dose variation predicted was 2.06% in 15MV of measured chamber dose and -2.06% of measured gafchromic film dose in 6MVFFF. CCC maximum dose variation predicted was 2.68% of measured chamber dose in 6MV and 3.31% of measured gafchromic film dose in 6MV whereas PB maximum dose variation predicted was -5.94% in 15MV of measured chamber dose and -11.6% of measured gafchromic film dose in 6MVFFF.Conclusion: Low-cost in-house phantoms can be utilised to assess point and planar doses during patient-specific quality assurance in centres that don't have accessibility to phantoms due to the high cost of commercially available tools.


Assuntos
Fótons , Planejamento da Radioterapia Assistida por Computador , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Fótons/uso terapêutico , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
4.
Prep Biochem Biotechnol ; 47(1): 8-18, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-26914524

RESUMO

Simultaneous production of xylanase and pectinase by Bacillus pumilus AJK under submerged fermentation was investigated in this study. Under optimized conditions, it produced 315 ± 16 IU/mL acidic xylanase, 290 ± 20 IU/mL alkaline xylanase, and 88 ± 9 IU/mL pectinase. The production of xylano-pectinolytic enzymes was the highest after inoculating media (containing 2% each of wheat bran and Citrus limetta peel, 0.5% peptone, 10 mM MgSO4, pH 7.0) with 2% of 21-hr-old culture and incubated at 37°C for 60 hr at 200 rpm. Xylanase retained 100% activity from pH 6.0 to10.0 after 3 hr of incubation, while pectinase showed 100% stability from pH 6.0 to 9.0 even after 6 hr of incubation. Cost-effective and concurrent production of xylanase and pectinase by a bacterial isolate in the same production media suggests its potential for various biotechnological applications. This is the first report of simultaneous production of industrially important extracellular xylano-pectinolytic enzymes by B. pumilus.


Assuntos
Análise Custo-Benefício , Endo-1,4-beta-Xilanases/biossíntese , Pectinas/metabolismo , Poligalacturonase/biossíntese , Xilanos/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática , Fermentação , Concentração de Íons de Hidrogênio , Poligalacturonase/metabolismo , Especificidade por Substrato , Temperatura
5.
Vet World ; 8(3): 320-5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27047091

RESUMO

AIM: The aim of the present study was to assess the influence of temperature and humidity prevalent under subtropical climate on the breeding values for fertility traits viz. service period (SP), pregnancy rate (PR) and conception rate (CR) of Murrah buffaloes in National Dairy Research Institute (NDRI) herd. MATERIALS AND METHODS: Fertility data on 1379 records of 581 Murrah buffaloes spread over four lactations and climatic parameters viz. dry bulb temperature and relative humidity (RH) spanned over 20 years (1993-2012) were collected from NDRI and Central Soil and Salinity Research Institute, Karnal, India. Monthly average temperature humidity index (THI) values were estimated. Threshold THI value affecting fertility traits was identified by fixed least-squares model analysis. Three zones of non-heat stress, heat stress and critical heat stress zones were developed in a year. The genetic parameters heritability (h(2)) and repeatability (r) of each fertility trait were estimated. Genetic evaluation of Murrah buffaloes was performed in each zone with respect to their expected breeding values (EBV) for fertility traits. RESULTS: Effect of THI was found significant (p<0.001) on all fertility traits with threshold THI value identified as 75. Based on THI values, a year was classified into three zones: Non heat stress zone(THI 56.71-73.21), HSZ (THI 75.39-81.60) and critical HSZ (THI 80.27-81.60). The EBVfor SP, PR, CR were estimated as 138.57 days, 0.362 and 69.02% in non-HSZ while in HSZ EBV were found as 139.62 days, 0.358 and 68.81%, respectively. EBV for SP was increased to 140.92 days and for PR and CR, it was declined to 0.357 and 68.71% in critical HSZ. CONCLUSION: The negative effect of THI was observed on EBV of fertility traits under the non-HSZ and critical HSZ Thus, the influence of THI should be adjusted before estimating the breeding values for fertility traits in Murrah buffaloes.

6.
Bioresour Technol ; 120: 322-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22796145

RESUMO

Efficiency of xylano-pectinolytic enzymes in deinking of school waste paper for its reuse has been investigated in the present study. Enzymatic deinked pulp decreased the requirement of chemicals to nearly 50% and gave same optical properties of pulp as obtained by conventional deinking process. This biodeinking plus chemical deinking approach resulted in a decrease of 20.15% and 22.64% in BOD and COD values of effluents and a gain of 10.71% in viscosity, 7.49% in breaking length, 10.52% in burst factor and 6.25% in tear factor as compared to conventional chemical deinking. This is the first report mentioning the use of xylanase and pectinase produced from a cellulase free alkalo-thermotolerant bacterial strain in the same cost effective agricultural residues based production medium for deinking and will help in making the process ecofriendly with 50% reduction in chemicals, commercially viable with better paper quality.


Assuntos
Endo-1,4-beta-Xilanases/metabolismo , Química Verde/economia , Química Verde/métodos , Tinta , Papel , Poligalacturonase/metabolismo , Resíduos/análise , Análise Custo-Benefício , Concentração de Íons de Hidrogênio , Instituições Acadêmicas , Tensoativos/química , Temperatura , Fatores de Tempo , Eliminação de Resíduos Líquidos
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