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991.
Indrajit Ghosh Sayanti Kar Tamasha Chatterjee Nirjhar Bar Sudip Kumar Das 《Sustainable Chemistry and Pharmacy》2021
Coconut coir (Cocos nucifera L.), particle size 300–850 μm, has been identified as an adsorbent for safranin-O dye removal from aqueous solution. Bioadsorption efficiency is improved by modifying untreated coconut coir (UCC) with 1 N phosphoric acid (PCC) and 1 N sulphuric acid (SCC). The acid treatment enhances the surface area of adsorbents and accelerates more dye uptake. The adsorption process is optimized by varying the physicochemical conditions like initial pH, adsorbent amount, contact time, initial dye concentration, and temperatures. The adsorption process's optimum pH is 4, 6, and 6, respectively, using UCC, PCC, and SCC adsorbents.In contrast, more than 98% of dye removal has been observed at the lower concentration of dyes up to 200 mg/L at 303 K. Maximum dye removal is possible at 75 mg/L of dye concentration. UCC, PCC, and SCC adsorbents’ adsorption capacity is 80.32 mg/g, 96.81 mg/g, and 89.53 mg/g, respectively, at 303 K temperature. Langmuir and Tempkin model and the pseudo-second-order model are the best-fitted models for isotherm and kinetic study. Thermodynamic parameters indicate the adsorption process is viable, spontaneous, exothermic. 75% glacial acetic acid is the most potent solvent for safranin-O dye extraction from dye loaded biomass. The functional groups and different interactions are identified to establish the adsorption mechanism. The PCC adsorbent has been used for scale-up design. The multiple polynomial regression (MPR) successfully predicts the dye removal efficiency for individual adsorbents. The modeling of the Genetic Algorithm has also been done successfully. 相似文献
992.
S A Yoganathan K J Maria Das K Maria Midunvaleja D Gowtham Raj Arpita Agarwal J Velmurugan Shaleen Kumar 《The British journal of radiology》2015,88(1054)
Objective:
The aim of this work was to evaluate the quality of kilovoltage (kV) cone beam CT (CBCT) images acquired during arc delivery.Methods:
Arc plans were delivered on a Catphan® 600 phantom (The Phantom Laboratory Inc., Salem, NY), and kV CBCT images were acquired during the treatment. The megavoltage (MV) scatter effect on kV CBCT image quality was evaluated using parameters such as Hounsfield unit (HU) accuracy, spatial resolution, contrast-to-noise ratio (CNR) and spatial non-uniformity (SNU). These CBCT images were compared with reference scans acquired with the same acquisition parameters without MV “beam on”. This evaluation was carried out for different photon beams (6 and 15 MV), arc types (half vs full arc), static field sizes (10 × 10 and 25 × 25 cm2) and source-to-imager distances (SID) (150 and 170 cm).Results and Conclusion:
HU accuracy, CNR and SNU were considerably affected by MV scatter, and this effect was increased with increasing field size and decreasing photon energy, whereas the spatial resolution was almost unchanged. The MV scatter effect was observed to be more for full-rotation arc delivery than for half-arc delivery. In addition, increasing the SID resulted in decreased MV scatter effect and improved the image quality.Advances in knowledge:
Nowadays, volumetric modulated arc therapy (VMAT) is increasingly used in clinics, and this arc therapy enables us to acquire CBCT imaging simultaneously. But, the main issue of concurrent imaging is the “MV scatter” effect on CBCT imaging. This study aims to experimentally quantify the effect of MV scatter on CBCT image quality. 相似文献993.
994.
Medical Data Management (MDM) domain consists of various issues of medical information like authentication, security, privacy, retrieval and storage etc. Medical Image Watermarking (MIW) techniques have recently emerged as a leading technology to solve the problems associated with MDM. This paper proposes a blind, Contourlet Transform (CNT) based MIW scheme, robust to high JPEG and JPEG2000 compression and simultaneously capable of addressing a range of MDM issues like medical information security, content authentication, safe archiving and controlled access retrieval etc. It also provides a way for effective data communication along with automated medical personnel teaching. The original medical image is first decomposed by CNT. The Low pass subband is used to embed the watermark in such a way that enables the proposed method to extract the embedded watermark in a blind manner. Inverse CNT is then applied to get the watermarked image. Extensive experiments were carried out and the performance of the proposed scheme is evaluated through both subjective and quantitative measures. The experimental results and comparisons, confirm the effectiveness and efficiency of the proposed technique in the MDM paradigm. 相似文献
995.
Pranab Das Jagat Ram Gagandeep Singh Brar Mangat R Dogra 《Indian journal of ophthalmology》2009,57(6):431-436
Purpose:
To evaluate the outcome of intraocular lens (IOL) implantation using capsular tension ring (CTR) in subluxated crystalline or cataractous lenses in children.Setting:
Tertiary care settingMaterials and Methods:
We prospectively studied 18 eyes of 15 children with subluxation of crystalline or cataractous lenses between 90° up to 210° after phacoemulsification, CTR and IOL implantation. Each child was examined for IOL centration, zonular dehiscence and posterior capsular opacification (PCO).Results:
Age of the patient ranged between five to 15 years. Out of 18 eyes, seven had traumatic and 11 had spontaneous subluxation of crystalline or cataractous lens. Phacoemulsification was successfully performed with CTR implantation in the capsular bag. Intraoperative zonular dialysis occurred in two eyes. Anterior vitrectomy was performed in six eyes to manage vitreous prolapse. IOL implanted was polymethyl methacrylate (PMMA) in eight eyes, hydrophobic acrylic in seven and hydrophilic acrylic in three. Follow-up ranged from 24 months to 72 months. Sixteen eyes had a best corrected visual acuity of 20/40 or better. Nine eyes developed significant PCO and were managed with Neodymium Yttrium Aluminum Garnet (Nd:YAG) laser posterior capsulotomy. One eye with acrylic IOL in the capsular bag had IOL dislocation after two years which was managed with vitrectomy and secondary trans-scleral fixation of IOL.Conclusions:
Phacoaspiration with CTR implantation makes capsular bag IOL fixation possible in most of the eyes with subluxated crystalline or cataractous lenses. PCO still remains a challenge in children with successful phacoaspiration with CTR implantation 相似文献996.
997.
998.
999.
Aritra Das Roger Detels Abdelmonem A. Afifi Marjan Javanbakht Frank J. Sorvillo Samiran Panda 《Quality of life research》2017,26(8):2171-2180
Purpose
Helping children living with HIV (CLH) to attain an optimum quality of life is an important goal for HIV programs around the world. Our principal objectives were to determine the association of HIV infection with different domains of health-related quality of life (HRQoL) among 8- to 15-year-old CLH in India and to compare the HRQoL parameters between CLH and HIV-negative children born to HIV-infected parents (“HIV-affected”). We also assessed whether antiretroviral therapy (ART) and CD4 lymphocyte counts were associated with HRQoL among CLH.Methods
Using the “Quality of Life (health-related) of Children Living with HIV/AIDS in India” instrument, we interviewed 199 CLH and 194 HIV-affected children from three districts of West Bengal, India. Participants were asked to quantify the difficulties faced by them in six HRQoL domains: physical, emotional, social, school functioning, symptoms, and discrimination.Results
The mean age of the participants was 11.6 (SD?±?2.5) years. CLH, compared to HIV-affected children, had poorer scores on all HRQoL domains except ‘discrimination.’ Among CLH, there were no significant differences in HRQoL domain scores (except in the ‘discrimination’ domain) between ART-treated and -untreated groups. CD4 lymphocyte count was found to be a significant positive predictor of the ‘symptom’ scale score.Conclusions
In India, interventions for CLH mostly focus on biological disease. However, the current study revealed that HRQoL among CLH was much poorer than that of a socio-demographically comparable group. Culturally and developmentally appropriate psychosocial support measures for Indian CLH are urgently needed.1000.
Alison E. Willing Mahasweta Das Mark Howell Shyam S. Mohapatra Subhra Mohapatra 《CNS Neuroscience & Therapeutics》2020,26(6):616-627
Traumatic brain injury (TBI) causes death and disability in the United States and around the world. The traumatic insult causes the mechanical injury of the brain and primary cellular death. While a comprehensive pathological mechanism of TBI is still lacking, the focus of the TBI research is concentrated on understanding the pathophysiology and developing suitable therapeutic approaches. Given the complexities in pathophysiology involving interconnected immunologic, inflammatory, and neurological cascades occurring after TBI, the therapies directed to a single mechanism fail in the clinical trials. This has led to the development of the paradigm of a combination therapeutic approach against TBI. While there are no drugs available for the treatment of TBI, stem cell therapy has shown promising results in preclinical studies. But, the success of the therapy depends on the survival of the stem cells, which are limited by several factors including route of administration, health of the administered cells, and inflammatory microenvironment of the injured brain. Reducing the inflammation prior to cell administration may provide a better outcome of cell therapy following TBI. This review is focused on different therapeutic approaches of TBI and the present status of the clinical trials. 相似文献