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Several studies have demonstrated low rates of local recurrence with brachytherapy-based accelerated partial breast irradiation (APBI). However, long-term outcomes on toxicity (e.g. telangiectasia) and cosmesis remain a major concern. The purpose of this study is to investigate the dosimetric feasibility of using targeted non-toxic radiosensitizing gold nanoparticles (GNPs) for localized dose enhancement to the planning target volume (PTV) during electronic brachytherapy APBI while reducing normal tissue toxicity. We propose to incorporate GNPs into a micrometer-thick polymer film on the surface of routinely used lumpectomy balloon applicators and provide subsequent treatment using a 50 kVp Xoft device. An experimentally determined diffusion coefficient was used to determine space-time customizable distribution of GNPs for feasible in-vivo concentrations of 7 mg/g and 43 mg/g. An analytical approach from previously published work was employed to estimate the dose enhancement due to GNPs as a function of distance up to 1 cm from the lumpectomy cavity surface. Clinically significant dose enhancement values of at least 1.2, due to 2 nm GNPs, were found at 1 cm away from the lumpectomy cavity wall when using electronic brachytherapy APBI. Higher customizable dose enhancement was also achieved at other distances as a function of nanoparticle size. Our preliminary results suggest that significant dose enhancement can be achieved to residual tumor cells targeted with GNPs during APBI with electronic brachytherapy. [ABSTRACT FROM AUTHOR]

Present work presents small signal stability analysis of an autonomous hybrid energy system with dish-Stirling solar thermal systems (DSTS) in integration with diesel engine generators (DEG), fuel cells (FC), battery energy storage system (BESS), and aqua electrolyzer (AE). The performance of Genetic algorithm (GA) optimized integral (I), proportional plus integral (PI), and proportional-integral-derivative (PID) controllers in containing the frequency deviation in the proposed system has been investigated. The dynamic performance of all three controllers, so optimized, is compared with manually tuned I controller. Simulation results revealed that the performance of the GA optimized PID controller is found to be the best amongst all three controllers. Further, sensitivity analysis is carried out to access the robustness of the controllers. [ABSTRACT FROM AUTHOR]

Abstract: Urea-succinic acid crystals have been grown at room temperature from aqueous solution in the presence of maleic acid by a slow evaporation technique. The structural parameters were determined using powder X-ray diffraction (XRD) and found to have monoclinic symmetry (space group P21/m) with a=9.902, b=17.510, c=5.555Å and α=γ=90°, β=96.46°. The transparency and optical analysis were carried out using UV–vis analysis. The optical band gap is found to be 4.71eV. The presence of various functional groups was confirmed by FTIR analysis. The samples have shown piezoelectric behavior with a fairly good piezoelectric charge coefficient (d 33) of 5pC/N, when it is poled at 7kV/cm. The hysteresis loop was plotted and the remnant polarization and coercive field were found to be 2.8μC/cm2 and 4kV/cm, respectively. The dielectric analysis was carried out as a function of temperature at various frequencies and the results were also discussed. [ABSTRACT FROM AUTHOR]

In this study, we have synthesized a new family of bioactive glass (BAG) comprising of SiO 2 , Na 2 O, CaO, K 2 O, P 2 O 5 and MgO via sol-gel route. The composition of these oxides has been selected in such a way that the BAG has a coefficient of thermal expansion close to the 316L stainless steel (SS). In vitro test by soaking the BAG in simulated body fluid (SBF) showed good bioactivity due to ion exchange between alkali ions from the BAG and the ions present in the SBF. The 316L SS substrates were textured using laser before application of BAG using sol-gel dip coating. Pull off test showed that the adhesion strength in case of textured and non-textured surfaces were 4.2 MPa and 2.46 MPa, respectively. This implies that texturing of the surface is helpful in increasing the adhesion strength of the coating. The bioactive glass-coated textured surface of 316L SS substrate showed better corrosion resistance in SBF than the bare substrate for which the respective corrosion current densities were 35 nA/cm2 and 353 nA/cm2, thereby indicating that the single layer sol-gel dip coating of bioactive glass improved the corrosion resistance of the 316L SS implants. The analysis of scanning electron microscopy (SEM) images of the coating after immersion in SBF shows the formation and growth of the apatite layer that will further inhibit the corrosion of the substrate. These results demonstrate the potential of the synthesized BAG as a coating material for 316L SS implants. [ABSTRACT FROM AUTHOR]

Abstract: Wind, Solar photovoltaic and solar thermal power systems are emerging renewable energy technologies and can be developed as viable options for electricity generation in future. In this paper, autonomous hybrid generation systems consisting of wind turbine generators (WTGs), solar thermal power system (STPS), solar photovoltaic (PV), diesel engine generators (DEGs), fuel cells (FCs), battery energy storage system (BESS), flywheel (FW), ultra capacitors (UCs) and aqua electrolyzer (AE) have been considered for simulation studies. The power system frequency deviates for sudden changes in load or generation or the both. The comparative performance of the controllers installed to alleviate this frequency deviation for different hybrid systems, is carried out using time domain simulation. In practice, controllers (PI or PID) are tuned manually which is difficult and time consuming. The computational intelligence has opened paths to a new generation of advanced process control. Here, GA is used for optimization of controllers’ gains of the proposed hybrid systems. The simulation results demonstrate the effectiveness of the GA based controllers in terms of reduced settling time, overshoot and oscillations. The results are compared with conventional controllers. [Copyright &y& Elsevier]

Abstract: Aflatoxin B1 (AFB1), is a food borne mycotoxin produced by fungal species of the genera Aspergillus. To elucidate the teratogenic effects, AFB1 was dissolved in corn oil and given orally to New Zealand White rabbits during 6–18 days of gestation with the dose levels of 0.025, 0.05 and 0.1mg/kg body weight. To assess pathomorphological features of the anomalies induced by AFB1, the fetal serial sections were histologically examined. There was no maternal mortality in any group. There was non-significant decrease in percent of live fetuses and increase in the percent resorptions and post-implantation losses at 0.1mg/kg dose group as compared with those of controls. The mean crown to rump lengths of 0.05 and 0.1mg/kg dose groups were significantly reduced than that of the control. The mean fetal weights were significantly reduced in 0.1mg/kg dose group than that of other treated groups. The gross anomalies observed included wrist drop and enlarged eye socket whereas, skeletal anomalies were agenesis of caudal vertebrae, incomplete ossification of skull bones and bent metacarpals. The visceral anomalies of microphthalmia and cardiac defects were seen at 0.1mg/kg dose group. The characteristic histological findings of fetal tissues were distortion of normal hepatic cord pattern and reduced megakaryocytes in liver, fusion of auriculo-ventricular valves, mild degenerative changes in myocardial fibers, microphthalmic eyes and lenticular degeneration. The results of this study indicated that AFB1 was found to be teratogenic in rabbits when given by oral route during gestation days 6–18 and the dose of 0.1mg/kg could be considered as the minimum oral teratogenic dose. The histological examination of the fetal tissues indicated its importance in identifying the visceral anomalies which were otherwise not visible. [Copyright &y& Elsevier]

Purpose Single lung transplantation is an acceptable therapeutic option. Here we use our single lung porcine allograft as a vehicle for stem cell transfer. We present our protocol for perfusion of porcine lungs with human stem cells using our ex-vivo machine. Methods Adult pigs underwent unilateral left pneumonectomy. The explanted lungs were removed from surgical field and connected to ex-vivo circuit. Porcine lungs were perfused with human albumin after explanation. Lungs were ventilated during perfusion. Total ex vivo perfusion <3 hours. 2 methods of BMC administration were compared: In group 1 CD133+ cells were only passed through the needle. In group2, MSCs were perfused into the pulmonary artery using the ex vivo machine Results 1. Human male somatic CD133+ Cells were passed through a Microlance needle (BD Gr.20, ∅ 0,8 × 40 mm, 26 Gauge)without injection into the lung. 750,000 human CD133+ cells (mobilized peripheral blood), purity (92.4-99.4%), frozen sample were used and different verification runs pump/syringe (n=10, flow rate up to 4mL/min, 30sec), viability was not unchanged (Table 1). 2. 100,000,000 human BMCs were perfused using the ex-vivo machine. The viability of the cells before and after lung perfusion did not show any significant in regard to viability rate, FACS and histological characteristics. Conclusion Both methods showed safe application route for pulmonary stem cell transfer. The viability of CD105+/45- cells is not as affected during ex vivo perfusion as rest of the cells. The Ex-Vivo mediated transfer is more practical for lung treatment. More histologic and cell culture studies are needed to confirm the feasibility. [ABSTRACT FROM AUTHOR]

Cancer is one of the leading causes of death all over the world. Among the strategies that are used for cancer treatment, the effectiveness of chemotherapy is often hindered by factors such as irregular and non-uniform uptake of drugs inside tumor. Thus, accurate prediction of drug transport and deposition inside tumor is crucial for increasing the effectiveness of chemotherapeutic treatment. In this study, a computational model of human brain tumor is developed that incorporates dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI) data into a voxelized porous media model. The model takes into account realistic transport and perfusion kinetics parameters together with realistic heterogeneous tumor vasculature and accurate arterial input function (AIF), which makes it patient specific. The computational results for interstitial fluid pressure (IFP), interstitial fluid velocity (IFV) and tracer concentration show good agreement with the experimental results. The computational model can be extended further for predicting the deposition of chemotherapeutic drugs in tumor environment as well as selection of the best chemotherapeutic drug for a specific patient. [ABSTRACT FROM AUTHOR]

Abstract: Lead free piezoelectric Bi0.5(Na0.5K0.5)0.5TiO3 (pure and 1wt.%, 2wt.%, 4wt.% Sb-doped) ceramics were synthesized away from its MPB. The crystalline nature of the BNKT ceramic was studied by XRD and SEM. Depolarization temperature (T d ) and transition temperature (T c ) were observed through phase transitions in dielectric studies which were found to increase after Sb-doping, thus increasing its usable temperature range. In the study of relaxation behavior, the activation energy for relaxation was found to be 0.33, 0.43, 0.57 and 0.56eV for pure and Sb-doped samples, respectively. All samples were found to exhibit normal Curie–Weiss law above their T c . Doping of Sb was found to restrain the diffused character of the pure sample. In P–E loop, Sb-doping was found to increase the ferroelectric properties. Pure and Sb-doped BNKT ceramics exhibited high values of piezoelectric charge coefficient (d 33) as 115, 121, 129 and 100pC/N, respectively. [Copyright &y& Elsevier]

Abstract: Background: Moderate alcohol consumption is known to be protective against coronary heart disease (CHD). However, the INTERHEART study, a case–control study of acute myocardial infarction (MI) patients, revealed that alcohol consumption in South Asians was not protective against CHD. We therefore planned to study cardiovascular risk factor and CHD prevalence among male alcohol users as compared to age matched lifetime abstainers. Methods: The subjects for this study were recruited from a cross-sectional survey carried out among employees and their family members aged 20–69 years in 10 medium-to-large industries from diverse sites in India, using a stratified random sampling technique. Information on education, behavioral, clinical and biochemical risk factors of CHD and alcohol use was obtained through standardized instruments. CHD diagnosis was based on Rose Questionnaire or a prior physician diagnosed CHD. Results: A total of 4465 subjects were present or past alcohol users. The mean age of alcohol users and lifetime abstainers was 42.8±11.0 years and 42.8±11.1 years, respectively (p =0.90). Systolic blood pressure and diastolic blood pressure were significantly higher in alcohol users (128.7±17.6mmHg/80.1±11.3mmHg) as compared to lifetime abstainers (126.9±15.9mmHg/79.5±10.3mmHg, p <0.01). Fasting blood sugar in alcohol users (98.7±30.5mg%) was also significantly higher than lifetime abstainers (96.6±26.0mg%, p <0.01). Total cholesterol was lower in alcohol users (179.1±41.1mg%) as compared to lifetime abstainers (182.7±38.2mg%, p <0.01). HDL cholesterol was higher in alcohol users (42.9±10.8mg%) as compared to lifetime abstainers (41.3±10.0mg%, p <0.01). Body mass index (BMI) was lower in alcohol users as compared to lifetime abstainers (22.7±4.1kg/m2 vs. 24.0±3.3kg/m2, p <0.001). Tobacco use was significantly higher in alcohol users (63.1% vs. 20.7%). The odds ratio (OR) of having CHD after adjusting for tobacco use, BMI and education was 1.4 (95%CI 1.0–1.9) in alcohol users as compared to controls. The OR was 1.2 (95%CI 0.8–1.6) in occasional alcohol users, 1.6 (95%CI 1.0–2.2) in regular alcohol users and 2.1 (95% CI 1.1–3.0) in past alcohol users as compared to controls. Conclusion: We did not observe an inverse (protective) association between alcohol intake and the prevalence of CHD. In contrast, our study indicated an association in the reverse direction, suggesting possible harm of alcohol for coronary risk in Indian men. This relationship needs to be further examined in large, prospective study. [Copyright &y& Elsevier]

Abstract: Background: Polymorphisms in genes coding for chemokine receptors, CCR2 and CCR5 have been studied as genetic markers of coronary artery disease (CAD). V64Ile polymorphism in CCR2 has been implicated in the manifestation of myocardial infarction in different populations, but data on association of the CCR5 deletion variant in etiology of CAD are conflicting. In the present study we tested genetic association between CCR5 Δ32 polymorphism and CAD among North Indians (Uttar Pradesh). Methods: Two hundred angiographically proven patients with coronary artery disease and two hundred age, sex and ethnically matched controls were genotyped for CCR5 Δ32 polymorphism by polymerase chain reaction. Genotype/allele frequencies were compared in patients and controls using the chi-square test. Results: The frequency of the heterozygote genotype in the population, including both patient and control group, was 3% and the frequency of the mutant allele Δ32 was 1.5%. CAD patients had a three times higher (4.6% vs. 1.5%) frequency of heterozygote genotype but the differences were statistically not significant. Association analysis did not achieve statistical significance, though odds ratio of 3.13 was observed for heterozygote genotype. Conclusions: The allele frequency of the CCR5 Δ32 polymorphism in CAD patients is 2.25% and 0.75% among controls but the differences were not significant. Overall this fits well with the pattern of CCR5 Δ32 allele frequency in Indian subcontinent where it varies from 1 to 3%. The heterozygote (+/ Δ32) genotype does not seem to have any protective role against development of CAD in this population. In fact, North Indian CAD had a higher frequency of CCR5 Δ32 allele suggesting a possible susceptibility trend (odds ratio 3.08, CI 0.83–11.46, chi-square 2.167, NS). [Copyright &y& Elsevier]

Langmuir supercells (LS) are full-depth Langmuir circulations in unstratified shallow shelves. A Reynolds-averaged Eulerian formulation is developed resolving LS as a secondary component to the wind-driven mean shear current. This formulation is combined with Lagrangian particle tracking to investigate oil droplet entrainment induced by LS as a function of wind stress. Two cases are simulated, one in which 500-μm oil droplets are released into a steady field of LS generated by a wind stress of 0.1 N m−2 and waves of intermediate wavelength λ = 6 H where H = 15 m is the water column depth, significant amplitude of 0.6 m and period of 8 s. In the second case, the 500-μm oil droplets are released into a steady field of LS generated by the same wave forcing but with a weaker wind stress of 0.025 N m−2. It is found that the greater wind stress leads to LS able to spread the droplets throughout upwelling and downwelling limbs of the cells within the first 80 minutes after release. The weaker wind leads to weaker LS that, within the same time after release, limit the dispersion of the droplets to the downwelling limbs of the cells forming Stommel retention zones for a prolonged time. • Langmuir supercells (LS) are wind/wave-driven Langmuir cells engulfing shallow water. • RANS simulation of LS with Lagrangian tracking is used to track 500-μm oil droplets. • LS is simulated for intermediate waves and wind stresses of 0.1 and 0.025 N/m2 • The 0.1 N/m2 LS homogenizes the oil along the up- and downwelling limbs of the cells. • The weaker wind LS accumulates the oil in Stommel retention zones for prolonged times. [ABSTRACT FROM AUTHOR]