28 research outputs found

    Corrosion Control of Mg-Zn Implant Alloys in Simulated Body Fluid

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    Magnesium alloys have recently attracted the attention as a new biodegradable material.  In this study, Mg-Zn alloys (1-4wt.% Zn) were fabricated with high purity raw materials using a clean melting process (fluxless method) and a protective atmosphere of CO2 + 0.4 SF6. The as-cast microstructures of the investigated alloys were characterized by optical and scanning electron microscopes, EDS and XRD. Corrosion properties of the prepared alloys were examined in simulated body fluid (SBF) by electrochemical techniques and immersion test (hydrogen evolution method).  Surface modification of the prepared alloys was performed using micro arc oxidation (MAO) treatment and hydroxiapatite (HA) coating. The results of the as-cast microstructure showed that Zn up to 2 wt% was completely dissolved in a-Mg matrix. On increasing Zn content (> 2wt%) the grain size decreased and a second MgZn2 phase was observed. Corrosion testing results revealed that Mg-1,2,3 wt% Zn have almost the same corrosion rates (0.025 mm/y) whereas Mg-4Zn has the highest degradation rate. Hydroxiapatite (HA) coating on micro-arc oxidation (MAO) treated magnesium alloys formed a dense and compact layer on the surface of magnesium alloys which had greatly improved surface properties and enhanced corrosion resistance of the prepared alloys. Keywords: Mg alloys, implants, biodegradable, corrosion, surface modificatio

    Novel Graphene‐Based Foam Composite As a Highly Reactive Filter Medium for the Efficient Removal of Gemfibrozil from (Waste)Water

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    This is the final version. Available on open access from Wiley via the DOI in this recordData Availability Statement; The data that support the findings of this study are available in the supplementary material of this article.Graphene-based materials have emerged as alternative adsorbents, but their success in removing pharmaceutical contaminants has been limited due to degradation caused by restacking and limited control over their sizes and porosities. Driven by this issue, in the current study, to counteract the restacking behavior, graphene sheets are supported on a thread/rod-like matrix structure in a boron nitride foam material, and a novel porous composite foam-supported graphene is synthesized. The as-prepared novel composite offers extraordinary features, such as high absorption kinetics, large available surface area, high porosity (>98%), ecofriendliness and cost-effective synthesis, and excellent affinity to emerging pharmaceutical contaminants. When batch-testing graphene-based foam material and porous graphene nanosheets to remove gemfibrozil (GEM) from wastewater samples, rapid adsorption kinetics (<5 min) are exhibited by the graphene-based foam. Column filter studies are conducted for both materials to test their performance in removing GEM from distilled water, synthetic graywater, and actual wastewater. Overall, the foam composite-based filter marginally outperforms the sand-supported graphene filter and significantly outperforms the unsupported graphene filter. A numerical MATLAB model is developed to simulate the reactive solute transport of GEM influent through the foam filter. Also, a formal sensitivity analysis is conducted to identify the key parameters influencing the model results.Department of Science and Technology, Government of IndiaNatural Environment Research Council (NERC

    Novel anticancer drug delivery system based on zeolite encapsulating Hamelia patens leaf and flower extracts

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    Nanotechnology had placed an impact in improving the antiproliferative activity of crude leaf (CL) and flower (CF) extracts of Hamelia patens on the liver (HEPG2) and breast (MCF7) carcinoma cell lines, after their encapsulation onto zeolite (ZSM-5) nanopores, which acts as a drug delivery system (DDS). The cytotoxicity of the new formulas showed remarkable improvement in the activities on HEPG2. CL had low activity on HEPG2, at the tested concentrations, but the ZSM-5 loaded one (CLZ) showed enhanced action with IC50=42 ÎŒg/mL. Also, the cytotoxicity of CF improved after Zeolite incorporation, where the IC50 has been changed from 48 ÎŒg/mL for CF to 25 ÎŒg/mL for CFZ. Moreover, the polar fraction of leaves extracted by methanol (Me.L) showed improvement on the cytotoxicity on MCF7 for zeolite loaded formula (Me.Z) (IC50 had changed from 65 to 44.4 ÎŒg/mL). Quantitative estimations for polyphenolic contents as well as the phenolic profiles for CF and CL extracts were inspected using HPLC-DAD to explore the bioactive phytochemical compounds. Acute toxicity test showed that LD50 was 1500 and 2333 mg/kg b.wt. for CL and CF, respectively. The cytogenetic study was also done to detect the chromosome aberrations in somatic and germ cells after CL and CF administration to mice. DPPH antioxidant capacity assay revealed that CL has high redox-active effect than CF. This study is a contribution to the development of a creative new DDS that help in cancer treatment

    Unmet supportive care needs and desire for assistance in patients receiving radiation treatment: Implications for oncology nursing

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    Unmet supportive care needs can contribute to emotional distress and reduced quality of life for cancer patients. We undertook a supportive care needs assessment for patients undergoing radiation therapy to provide a basis for program planning. A self-report supportive care needs survey was completed by a convenience sample of 115 patients on days five, seven and 16 during their course of radiation. The most frequently identified physical unmet needs at all three times were fatigue (33%–49%), dry and itchy skin (24%–37%), and sleep difficulties (23%–30%). The number of patients citing these unmet needs increased significantly over the study time period. Within the emotional domain, worry (34.5%) was cited most frequently on day five. The number of individuals expressing worry did not decrease significantly by day 16. Across all domains and individual items, there was wide variation in the percentage of individuals who had an unmet need and also indicated they wanted help with that unmet need. This pattern remained consistent over time. This study emphasizes the need for a defined or intentional process to assess supportive care needs and patient desire for assistance or help with unmet needs. Note: The management of the peer review for this manuscript was undertaken by the former Editor in Chief for CONJ

    Besoins en soins de soutien non comblĂ©s et dĂ©sir de recevoir de l’aide de patients recevant de la radiothĂ©rapie : rĂ©percussions sur l’infirmiĂšre en oncologie

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    Les besoins en soins de soutien non comblĂ©s peuvent contribuer Ă  la dĂ©tresse psychologique et rĂ©duire la qualitĂ© de vie des patients atteints de cancer. Nous avons effectuĂ© une Ă©valuation des besoins en soins de soutien chez les patients qui recevaient de la radiothĂ©rapie pour la planification d’un programme. Un questionnaire d’auto-Ă©valuation des besoins en soins de soutien a Ă©tĂ© rempli par un Ă©chantillon de convenance de 115 patients les jours 5, 7 et 16 de leur radiothĂ©rapie. Les besoins physiques non comblĂ©s les plus nommĂ©s les trois fois Ă©taient la fatigue (33–49 %), une peau sĂšche prurigineuse (24–37 %) et les troubles du sommeil (23–30 %). Le nombre de patients mentionnant ces besoins non comblĂ©s a considĂ©rablement augmentĂ© au cours de l’étude. Sur le plan psychologique, l’inquiĂ©tude (34,5 %) arrivait en tĂȘte le jour 5. Le nombre de personnes exprimant de l’inquiĂ©tude n’a pas vraiment diminuĂ© avant le jour 16. Dans tous les domaines et pour tous les Ă©lĂ©ments individuels, il y avait une grande variation du pourcentage de patients qui avaient des besoins non comblĂ©s et qui ont indiquĂ© vouloir de l’aide concernant ces mĂȘmes besoins. Ce modĂšle est restĂ© cohĂ©rent au fil du temps. Cette Ă©tude fait ressortir le besoin de se doter d’un processus dĂ©fini ou intentionnel pour Ă©valuer les besoins en soins de soutien et le dĂ©sir du patient d’obtenir de l’assistance ou de l’aide pour combler ses besoins

    Removal of Cesium from Contaminated Waters by Employing Iron-Based Nanoparticles and Nanocomposites

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    Investigating the design parameters for a permeable reactive barrier consisting of nanoscale zero-valent iron and bimetallic iron/copper for phosphate removal

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    There is a growing interest in deploying nanoscale zero valent iron (NZVI) in permeable reactive barriers (PRBs) for groundwater remediation. In the present study a series of packed-column experiments were conducted in order to investigate the effectiveness of phosphorus removal from groundwater using NZVI and bimetallic NZVI/Cu as reactive materials within PRBs. Seven sets of packed-column experiments were conducted in order to study the effect of different design parameters for PRB; including delivery approach of NZVI into porous media, PRB's configuration, coexisting groundwater ions and change in flowrate. Results implied that doping NZVI surface with copper had an anti-aggregation effect and enhanced its performance in terms of phosphorus removal 2.2 times higher than bare NZVI. Moreover, the lower flowrate (10 ml/min) demonstrated improved phosphorus removal by 22% compared with higher flowrate (60 ml/min). Additionally, groundwater ions barely interfered phosphorus removal process with only ±6%. Overall, geochemical properties and characteristics of the supporting materials were key parameters in the removal process of phosphorus by NZVI/Cu

    Multi-functional magnesium hydroxide coating for iron nanoparticles towards prolonged reactivity in Cr(VI) removal from aqueous solutions

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    In this study, the reactive performance of magnesium hydroxide-coated iron nanoparticles (Fe @Mg(OH)2) was investigated for the removal of hexavalent chromium (Cr(VI)) from aqueous solutions. Short-and long-term progressive-release of Fe @Mg(OH)2 reactivity was evaluated through several batch tests. The Multi-functional effect of the environmentally-friendly Mg(OH)2 coating shell was represented by the progressive shell-dissolution in water and preventing the rapid corrosion of Fe-core, which resulted in a controlled release of Fe reactivity towards Cr(VI). Fe @Mg(OH)2 showed good performance in preserving Fe long-term reactivity within a wide range of pH (3.0-9.0) and temperature (15-55 oC). The long-term investigation of Fe @Mg(OH)2 performance towards Cr(VI) removal confirmed the progressive and maintained reactivity, represented by the continuous release of Fe electrons, to achieve 100% removal efficiency of 40 mg/L initial Cr(VI) concentration over 50 days reaction time, to be reported for the first time in the literature. Fe @Mg(OH)2 showed high regeneration abilities up to 5 cycles with 1.36 times average enhancement in Cr(VI) removal efficiency compared to that of Fe. Moreover, Fe @Mg(OH)2 achieved an increase in the shelf-live longevity performance up to 30 days without any storing solution with 90% final Cr(VI) removal efficiency after 180 min reaction time

    Does liver diffusion tensor imaging (L-DTI) has a role in differentiation of hepatic focal lesions? Analytic study for assessment of the value of L-DTI in differentiating hepatic focal lesions according to LI-RADS

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    Abstract Background Magnetic resonance imaging (MRI) plays an important role in the differentiation of hepatic focal lesions and diagnosis of hepatic malignancy, especially hepatocellular carcinoma which is a major health problem worldwide. Diffusion imaging is a functional MRI technique that became an essential part of MRI study of the liver. Recently, diffusion tensor imaging (DTI) is diffusion variant that can provide more information than conventional diffusion imaging based on the tissue anisotropy. The aim of this study was to present the role of DTI in the assessment and differentiation between hepatic focal lesions. Results Fifty-one patients having 95 hepatic focal lesions who underwent dynamic MRI with conventional diffusion imaging and DTI acquisition were included in the study. A positive moderate significant correlation was found between Fractional anisotropy (FA) values and Liver Imaging Reporting and Data System (LI-RADS) category while substantial negative significant correlation and moderate negative significant correlation were found between DTI-ADC and DWI-ADC values, respectively, with the LI-RADS category. There was a significant negative correlation between DTI-ADC and FA values. DTI-ADC showed a significant role in differentiation of benign from malignant lesions with cut-off value 0.905 × 10−3 having 88.7% sensitivity and 88.3% specificity compared to 78.5% and 68.7% for DWI-ADC, respectively. Also, it was found that FA value had a significant role in differentiation between benign and malignant lesions with cut-off value 0.34 having 87.1% sensitivity and 73.9% specificity. Conclusions DTI can be included in liver MRI studies for better tissue characterization as it may perform better than conventional DWI with higher sensitivity and specificity of DTI-ADC and FA values than conventional DWI-ADC
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