Shape Control of Composite Structures with Optimally Placed Piezoelectric Patches

The problem of shape control of composite laminated smart structures with piezoelectric patches placed at optimal location is considered in this thesis. Laminated plate structures with piezoelectric patches for shape control applications are modeled using a shear deformable plate formulation by including the piezoelectric layers into the plate substrate. A composite plate finite element model is also developed for composite plates with self-sensing actuators. Non-linear hysteresis models for piezoelectric materials are presented and discussed. Numerical simulation of composite plate structures with piezoelectric actuators is conducted and presented. The optimization problem of finding the optimal location of actuators using a linear quadratic control algorithm is done and the results are discussed. Static shape control strategies are also discussed

Adding 6 months of androgen deprivation therapy to postoperative radiotherapy for prostate cancer: a comparison of short-course versus no androgen deprivation therapy in the RADICALS-HD randomised controlled trial

Background Previous evidence indicates that adjuvant, short-course androgen deprivation therapy (ADT) improves metastasis-free survival when given with primary radiotherapy for intermediate-risk and high-risk localised prostate cancer. However, the value of ADT with postoperative radiotherapy after radical prostatectomy is unclear. Methods RADICALS-HD was an international randomised controlled trial to test the efficacy of ADT used in combination with postoperative radiotherapy for prostate cancer. Key eligibility criteria were indication for radiotherapy after radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to radiotherapy alone (no ADT) or radiotherapy with 6 months of ADT (short-course ADT), using monthly subcutaneous gonadotropin-releasing hormone analogue injections, daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as distant metastasis arising from prostate cancer or death from any cause. Standard survival analysis methods were used, accounting for randomisation stratification factors. The trial had 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 80% to 86% (hazard ratio [HR] 0·67). Analyses followed the intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov, NCT00541047. Findings Between Nov 22, 2007, and June 29, 2015, 1480 patients (median age 66 years [IQR 61–69]) were randomly assigned to receive no ADT (n=737) or short-course ADT (n=743) in addition to postoperative radiotherapy at 121 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 9·0 years (IQR 7·1–10·1), metastasis-free survival events were reported for 268 participants (142 in the no ADT group and 126 in the short-course ADT group; HR 0·886 [95% CI 0·688–1·140], p=0·35). 10-year metastasis-free survival was 79·2% (95% CI 75·4–82·5) in the no ADT group and 80·4% (76·6–83·6) in the short-course ADT group. Toxicity of grade 3 or higher was reported for 121 (17%) of 737 participants in the no ADT group and 100 (14%) of 743 in the short-course ADT group (p=0·15), with no treatment-related deaths. Interpretation Metastatic disease is uncommon following postoperative bed radiotherapy after radical prostatectomy. Adding 6 months of ADT to this radiotherapy did not improve metastasis-free survival compared with no ADT. These findings do not support the use of short-course ADT with postoperative radiotherapy in this patient population

Duration of androgen deprivation therapy with postoperative radiotherapy for prostate cancer: a comparison of long-course versus short-course androgen deprivation therapy in the RADICALS-HD randomised trial

Background Previous evidence supports androgen deprivation therapy (ADT) with primary radiotherapy as initial treatment for intermediate-risk and high-risk localised prostate cancer. However, the use and optimal duration of ADT with postoperative radiotherapy after radical prostatectomy remains uncertain. Methods RADICALS-HD was a randomised controlled trial of ADT duration within the RADICALS protocol. Here, we report on the comparison of short-course versus long-course ADT. Key eligibility criteria were indication for radiotherapy after previous radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to add 6 months of ADT (short-course ADT) or 24 months of ADT (long-course ADT) to radiotherapy, using subcutaneous gonadotrophin-releasing hormone analogue (monthly in the short-course ADT group and 3-monthly in the long-course ADT group), daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as metastasis arising from prostate cancer or death from any cause. The comparison had more than 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 75% to 81% (hazard ratio [HR] 0·72). Standard time-to-event analyses were used. Analyses followed intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov , NCT00541047 . Findings Between Jan 30, 2008, and July 7, 2015, 1523 patients (median age 65 years, IQR 60–69) were randomly assigned to receive short-course ADT (n=761) or long-course ADT (n=762) in addition to postoperative radiotherapy at 138 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 8·9 years (7·0–10·0), 313 metastasis-free survival events were reported overall (174 in the short-course ADT group and 139 in the long-course ADT group; HR 0·773 [95% CI 0·612–0·975]; p=0·029). 10-year metastasis-free survival was 71·9% (95% CI 67·6–75·7) in the short-course ADT group and 78·1% (74·2–81·5) in the long-course ADT group. Toxicity of grade 3 or higher was reported for 105 (14%) of 753 participants in the short-course ADT group and 142 (19%) of 757 participants in the long-course ADT group (p=0·025), with no treatment-related deaths. Interpretation Compared with adding 6 months of ADT, adding 24 months of ADT improved metastasis-free survival in people receiving postoperative radiotherapy. For individuals who can accept the additional duration of adverse effects, long-course ADT should be offered with postoperative radiotherapy. Funding Cancer Research UK, UK Research and Innovation (formerly Medical Research Council), and Canadian Cancer Society

A case-control study of serum and tissue catalase among morphological variants of vitiligo

Background: Role of oxidative stress in the pathogenesis of vitiligo. Aim: Estimation of serum and tissue catalase levels in morphological variants of vitiligo. Settings and Design: A prospective case-control study was conducted in the outpatient department of Dermatology in Safdarjung hospital. Materials and Methods: We estimated levels of serum and tissue catalase in 30 vitiligo patients and 30 matched healthy controls. Statistical Analysis: The data analysis was done in Statistical Package for Social Sciences (SPSS) version 21.0. Normality of data was tested by Kolmogorov–Smirnov test. Results: Serum and tissue catalase was lower in vitiligo patients than controls. Serum catalase was lowest in vulgaris type, whereas in the acrofacial type had lowest tissue catalase levels. Conclusion: Vitiligo patients have a generalized oxidative stress functioning at a higher pace as seen with decreased serum and tissue CAT which can well be taken as a marker of active disease and they can be helped with topical pseudoCAT preparations

In vitro-microenvironment directs preconditioning of human chorion derived MSC promoting differentiation of OPC-like cells.

The loss of oligodendrocyte progenitor cells (OPC) is a hallmark of perinatal brain injury. Our aim was to develop an in vitro culture condition for human chorion-derived mesenchymal stem cells (MSC) that enhances their stem cell properties and their capability to differentiate towards OPC-like cells. MSC were grown either in serum replacement medium (SRM) or serum-containing medium (SM) and tested for their morphology, proliferation, secretome, migration, protein expression and differentiation into OPC-like cells. MSC cultured in SRM condition have distinct morphology/protein expression profile, increased cell proliferation/migration and capacity to differentiate into OPC-like cells

Corrosion protection of mild steel by a new phosphonate inhibitor system in aqueous solution

A protective film has been developed on the surface of the mild steel in low chloride aqueous environment using a synergistic mixture of an eco friendly inhibitor, imino dimethyl phosphonic acid (IDMPA) and Zn2+. The synergistic effect of IDMPA in controlling corrosion of the mild steel has been investigated by gravimetric and electrochemical studies in the presence of Zn2+. The formulation consisting of IDMPA and Zn2+ has excellent inhibition efficiency. The mixed mode of inhibition studied by potentiodynamic polarization and electrochemical impedance spectroscopy has shown that the changes in the impedance parameters like charge transfer resistance (Rct) and constant phase element (CPE) confirm the strong adsorption on the mild steel. Surface characterization inspection using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) is used to ascertain the nature of the protective film. The mechanistic aspects of corrosion inhibition are proposed

Perceptions About E-Learning Among Undergraduate Medical Students: A Cross Sectional Study

The COVID-19 pandemic times showed the need for blending e-learning in medical education. The current study aims to find the perceptions of undergraduate medical students on e-learning. A questionnaire-based cross-sectional study was conducted on 848 students on perceptions about e-learning. Private college students and Phase IV students significantly faced more data exhaustion. The government college students and phase IV students significantly felt that classes were more monotonous. The longer duration of e-learning caused health effects. Thus, to bring about a better learning environment e-learning can be integrated into the MBBS curriculum as a supplement to bedside and small group learning

Exploring the Electronic Properties of Ribonucleic Acids Integrated Within a Schottky-Like Junction

Deoxyribonucleic acid (DNA), being the main biomolecule of life, has been studied extensively in terms of its electronic properties, charge transport mechanisms and potential use in nano-electronic devices. The ability of DNA to self-replicate, self-assemble and mediate charge transfer has made it an interesting molecule to multidisciplinary researchers. However, not much attention has been given to ribonucleic acid (RNA), which is an equally important biomolecule that shares some common features with DNA. Elucidation of RNA’s electronic behavior could provide more information regarding its electronic properties, potentially offering a new biomolecule for application in bioelectronics. In this work, RNA samples integrated within two metal electrodes were subjected to positive and negative bias potentials and their resulting current profiles were investigated. Interestingly, current rectification similar to electric field-induced semi-conductive behavior of conventional Schottky junctions was observed for all RNA samples tested, indicating highly characteristic RNA-specific Schottky profiles. A non-linear profile was observed from the current–voltage (I–V) characteristics of gold (Au)-RNA-Au structures showing resemblance to metal-DNA structures investigated previously. Various solid-state parameters such as turn-on voltage, shunt resistance, series resistance and ideality factor were also calculated to further understand the biomaterial’s solid-state behavior. These results successfully demonstrated the exciting observation of the semi-conductive-like behavior of RNA which could be utilized as a tool in molecular electronics. © 2019, The Minerals, Metals & Materials Society

The Cytoprotective Effects of Human Endothelial Progenitor Cell-Conditioned Medium Against an Ischemic Insult Are Not Dependent on VEGF and IL-8.

Endothelial progenitor cells (EPCs) promote revascularization and tissue repair mainly by paracrine actions. In the present study, we investigated whether EPC-secreted factors in the form of conditioned medium (EPC-CM) can protect cultured brain microvascular endothelial cells against an ischemic insult. Furthermore, we addressed the type of factors that are involved in the EPC-CM-mediated functions. For that purpose, rat brain-derived endothelial cells (rBCEC4 cell line) were exposed to EPC-CM pretreated with proteolytic digestion, heat inactivation, and lipid extraction. Moreover, the involvement of VEGF and IL-8, as canonical angiogenic factors, was investigated by means of neutralizing antibodies. We demonstrated that EPC-CM significantly protected the rBCEC4 cells against an ischemic insult mimicked by induced oxygen-glucose deprivation followed by reoxygenation. The cytoprotective effect was displayed by higher viable cell numbers and reduced caspase 3/7 activity. Heat inactivation, proteolytic digestion, and lipid extraction resulted in a significantly reduced EPC-CM-dependent increase in rBCEC4 viability, tube formation, and survival following the ischemic challenge. Notably, VEGF and IL-8 neutralization did not affect the actions of EPC-CM on rBCEC4 under both standard and ischemic conditions. In summary, our findings show that paracrine factors released by EPCs activate an angiogenic and cytoprotective response on brain microvascular cells and that the activity of EPC-CM relies on the concerted action of nonproteinaceous and proteinaceous factors but do not directly involve VEGF and IL-8