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Poly ( l -lacticacid) (PLLA) is an FDA approved material for bone tissue engineering but its inherent brittleness and low melting ability are major challenges for its large-scale commercial applications. This challenge can be overcome by making its blends. This study reports blends of PLLA with a relatively new class of polymer i.e. cyclic olefinic copolymer and their miscibility, thermal behavior, morphology, crystallinity, degradability, and excellent biocompatibility is evaluated. Blends were prepared by taking 5–30 weight percent COC with PLLA matrix using solvent casting method. Scanning electron microscopy (SEM) images revealed that PLLA/COC form miscible blends up to 5–20 wt% of COC. FTIR, XRD, and differential scanning calorimetry (DSC) data showed that addition of COC to PLLA resulted in decrease in crystallinity along with formation of new α′-crystalline phase which coexists with inherent α-phase of PLLA in the blends. The transformation of α′-form is due to the presence of Van der Waals forces of interactions of the polymer chain moieties between PLLA and COC. Interestingly, PLLA/COC blends exhibited superior mechanical properties in relation to the pure PLLA. Compressive modulus values for PLLA/COC 10wt% increased 117% as compared to pure PLLA. PLLA/COC blends at 10 wt% have maximum ultimate tensile strength, modulus, and toughness ~ 123%, 67.8% and, 18.87% respectively. PLLA/COC blends showed increased swelling and degradation results as compared to PLLA. PLLA/COC blends exhibited excellent cytocompatibility over PLLA with preosteoblast (MC3T3-E1) and bone marrow stem cells (BMSc) cell lines suggesting possible candidate for Bone Tissue Engineering.

Bone whitlockite (WH) exists in the collagen matrix along with hydroxyapatite (HA) and plays a vital role during earlier stages of bone development. It is present in short-range order and is difficult to identify in the bone, as compared to HA mineral, that covers 80% of the bone inorganic phase. It has the same structural analogy with β-TCP, but detailed structural and crystallographic analyses of bone have shown that β-tricalcium phosphate (β-TCP) is merely a synthetic analog of bone whitlockite, having the same crystalline structure but different chemically. WH contains magnesium at Ca(IV), Ca(V) positions, and HPO42− on a threefold axis in a rhombohedral crystal lattice. Its biocompatibility, functionality, negative surface charge, mechanical strength, and stability in physiological solvents make it an ideal bone substitute as compared to hydroxyapatite (HA) and β-TCP. It has magnesium as a major component that has a strong affinity with integrin protein. Integrin protein plays a vital role in bone tissue integration. It is bioresorbable and biodegradable and the rate of degradation complements with regeneration. However, despite these excellent properties, this material has always been overshadowed by other calcium phosphates (CaPs), because it is difficult to synthesize. In this review article, we present a comprehensive study on the difference in the crystalline structure of bone whitlockite and β-TCP, its presence in the natural system, and conditions under which its nucleation occurs in native bone and at lab scale. Furthermore, the reaction conditions that favor homogenous precipitation of synthetic WH and the role of magnesium in the stabilization of different CaPs to obtain pure WH phase are also discussed. Finally, the applications of WH in biomedical and for heavy metal adsorption are summarized.

This analysis explores stagnation point in Jeffery liquid flow over a stretchable cylinder. Heat and mass transfer are investigated through Cattaneo–Christov model with double stratification, heat source and thermal relaxation. Moreover, the flow of liquid is caused by stretchable cylinder. Cylindrical coordinates are used for mathematical formulations. The acquired boundary layer problems for stretchable cylinder are dealt through homotopy analysis method. Results of variables appeared in governing equations are disclosed through graphs for flow, temperature, concentration and skin friction. The findings of the study show that higher values of ratio parameter and Deborah number in terms of relaxation time reduce magnitude of drag coefficient while reverse trend is noted for larger Deborah number in terms of retardation time and curvature parameter. Comparison of present work with previous published date is presented.

The multiple travelling salesman problem (MTSP), an extension of the well-known travelling salesman problem (TSP), is studied here. In MTSP, starting from a depot, multiple salesmen require to visit all cities so that each city is required to be visited only once by one salesman only. It is NP-hard and is more complex than the usual TSP. So, exact optimal solutions can be obtained for smaller sized problem instances only. For large-sized problem instances, it is essential to apply heuristic algorithms, and amongst them, genetic algorithm is identified to be successfully deal with such complex optimization problems. So, we propose a hybrid genetic algorithm (HGA) that uses sequential constructive crossover, a local search approach along with an immigration technique to find high-quality solution to the MTSP. Then our proposed HGA is compared against some state-of-the-art algorithms by solving some TSPLIB symmetric instances of several sizes with various number of salesmen. Our experimental investigation demonstrates that the HGA is one of the best algorithms.

This paper proposes a novel multi- objective planning framework to determine optimal capacity of battery energy storage system (BESS) for coordinated operation of large scale offshore wind farm (OWF) and BESS. Multiple objectives such as battery cost and lifetime, availability of wind turbines (WTs), expected energy not supplied (EENS), loss of load hour (LOLH) and curtailment of wind energy have been considered for determining optimal capacity of BESS for OWF. Wake effect loss in OWF and uncertainty of wind speed have been also incorporated the optimal BESS framework for determining aforementioned objectives. Moreover, as WTs are susceptible to random failure, availability of WTs is an important issue which has been also considered in the planning stage for determining optimal size of BESS in this study. One of the main features of the proposed approach is that it provides flexibility to decision makers in selecting best available alternative for BESS (among different types) to minimize mismatch between forecasted generation schedule and actual generation of OWF, while taking into account economical and operational reliability issues. The effectivene ss of the proposed planning strategy has been validated through different case studies conducted on Horns Rev- 1 OWF situated in Denmark.

A detailed analytical and numerical investigation of Krause and Robert (KR) flow is done in this article. KR flow is directly derived from magnetohydrodynamics (MHD) equations by using dynamo theory that describes the process through which a rotating, convecting and electrically conducting fluid acts to maintain a magnetic field. The present work focuses on describing complex behavior and symmetry in KR flow. The existence of symmetry has a profound and far-reaching impact on the properties of solution of chaotic dynamical systems. The relation between the KR chaotic attractor with twofold symmetry and its projected image without symmetry is shown in this article. Chaotic behavior of KR flow is studied through Lyapunov spectrum and boundedness to specify the chaotic region. Moreover, the computation of the Hamilton energy shows that KR flow depends on all its variables and, therefore, enough energy is critical to generate wings of KR flow.

Low-voltage ride-through (LVRT) compliance of wind energy conversion systems is one of the significant concerns for both the wind industry and the system operator. In this study, power electronic-assisted on load tap changer (OLTC) is proposed as a pragmatic solution to enhance LVRT performance of wind turbine generator (WTG). Furthermore, a coordinated control strategy between OLTC and WTG controller is proposed to mitigate post-fault over-voltage issues that are encountered due to the relatively slow dynamics of hybrid OLTC. The results suggest that employing hybrid OLTC does not only improve LVRT compliance of WTG but also significantly improve voltage dip-induced delayed active power recovery of WTG.

The degree of malnutrition is very high in India. Early detection of the possibility for a child to be affected by malnutrition can combat the situation to some extent. Birth weight prediction of n...

Large-scale renewable energy integration and consequent displacement of synchronous machines result in low system inertia. Low system inertia leads to high rate of change of frequency, higher frequency nadir, and potentially require higher primary frequency reserve to stabilise system frequency following a sudden generation shortfall. To address such frequency stability issue in wind energy integrated system, this paper has proposed a new and realistic control strategy for inertial and primary frequency support from HVDC connected Offshore Wind Farms (OWF). The proposed control strategy, which is based on offshore AC voltage control is not only addressing limitations of high rate of frequency change in the offshore grid, but also does not result in any frequency deviation in the offshore grid while providing frequency support to the main grid. The proposed control strategy is robust for any frequency deviation in the main grid, which utilises HVDC converters to map onshore frequency variation in to voltage variation in the offshore grid, thus enabling adequate inertial and primary frequency support from the OWF. The proposed control strategy has been tested on two test systems and the results are compared with conventional method to demonstrate the robustness, effectiveness and reliability of the proposed frequency support strategy.

This paper presents an improved method to estimate the available inertia in an islanded AC microgrid. Inertia estimation is carried out based on measured frequency response for any arbitrary disturbance that occurs in the system. Modifications are made to the conventional swing equation-based curve-fitting method to obtain an accurate estimate for a system with high penetration of renewable generations. A polynomial curve fit over the total power generation is introduced to estimate the size of the disturbance accurately. Additionally, a variable order polynomial fit is carried out over the measured frequency, which not only improves the estimate of inertia but also helps to refrain the influence of network topology and size/location of the disturbance. The test microgrid system considered is a modified Standard IEEE distribution network, which consists of radial feeders and distributed generations. Firstly, the proposed method is tested on a system with only synchronous generations to assess the accuracy of the estimate. This is followed by the integration of Type 3 and Type 4 wind turbines, and a PV array within the microgrid system. Virtual inertia control is then implemented in the wind turbines to obtain inertial support. Estimation study of the microgrid system with virtual inertia is then carried out. The developed estimation method can accurately estimate the inertia provided by the synchronous sources within the generation mix. Finally, from all the results and observations, the inertia estimation process in a microgrid system is segregated into synchronous and nonsynchronous inertia estimation.

The structure-properties relationships of novel cyclic olefinic copolymer (COC)/poly(L-lactic acid) (PLLA) polymer blends are investigated by varying the PLLA content from 5–20 wt % in COC matrix, forming an immiscible blends at all concentrations. Despite immiscibility, COC favors the formation of α- crystal form of PLLA in the blends, contrary to the α’- crystal form in neat PLLA due to non-covalent interactions of the chain moieties as evident from x-ray diffraction, Fourier transform infrared spectrometer and differential scanning calorimetry. The COC/PLLA blends revealed tunable superior mechanical and barrier properties as compared to the neat counterparts. The tensile modulus, strength and toughness of COC/PLLA blends at 15 wt% are significantly enhanced ∼ 89 %, 103 % and one order of magnitude, respectively. Such reinforcement and super toughening mechanisms are pertaining to the effective dissipation of loads across the interfaces, enabling them to delay the crack growth by avoiding stress concentration sites. Likewise, the water vapor permeation (WVP) of the blends is reduced ∼ 4 times than neat COC.

This article investigates the effect of powder metallurgy processing parameters on multi-responses: mass density and hardness of Al2O3/Cu composite based on Taguchi method coupled with Grey relational analysis. Based on Taguchi’s L18 orthogonal array, the experimental trial runs were conducted with four controllable powder processing parameters: milling time, compaction pressure, sintering temperature and holding time. The Grey relational analysis (GRA) was performed to find the optimal powder processing condition with Grey relational grade (GRG) as a measure of performance index. Analysis of variance (ANOVA), 3D surface plots and contour plots were used to express the most influential parameter that affects mass density and hardness of Al2O3/Cu composite. Confirmation tests were conducted to make sure the validity of test results. The scanning electron microscope (SEM) images show the presence of Al2O3 particle in the composite. The Energy Dispersive X-Ray (EDX) spectrum indicates the presence of chemical elements: Cu, Al, O in the composite. The results show that the optimal powder metallurgy parameter combination is A2B3C3D1. The mean Grey relational coefficient (GRC) analysis shows that the mass density was more easily influenced by factors considered compare to hardness. The mean GRG result shows that the compaction pressure has the strongest correlation to responses. The result of 3D surface plots, contour plots and ANOVA indicate that the compaction pressure has most influential parameter that affect GRG. The % contribution of parameters shows that the % contribution of compaction pressure is significant (80.22%) compare to other main effects and interaction effects. The confirmation tests revealed that the performance characteristic of Al2O3/Cu composite was improved by GRA based Taguchi technique. The Monte Carlo simulated model summery show that based on Taguchi L18 Orthogonal Array design, one can easily find the reality of what will be happening in a process. Therefore, optimization of processes parameter could be simplified by using the Grey-based Taguchi method.

The work focuses on the exact solution of the perturbative model for a plane-parallel flow of two immiscible fluids under constant transversal magnetic field (Hartmann flow). The special case of the perturbation’s symmetry is considered: it is supposed that perturbations intensity depends just on specified two parameters and time. Nevertheless, the considered case seems to be common enough and can be considered as one of the flow stability criteria. To receive exact solution, the governing equation system is analyzed. It is shown that in the considered case, it can be reduced to heat equations for the nontrivial components. The perturbations considered in this work are not necessary of harmonic type and the corresponding equations on the perturbations are not Orr-Sommerfeld equations.

In this article, the hydrodynamic stability of the Couette flow of an electrically conducting fluid flowing in a parallel-plate channel with a normal magnetic field is investigated through a porous medium. The transport phenomena in the porous medium have been of enduring interest from the last few decades. The linear perturbation theory of hydrodynamic stability along with the presumption of low magnetic Reynolds number is applied to the governing equations to derive the governing magnetohydrodynamic stability equation. A Chebyshev collocation method is operated to numerically elucidate the magnetohydrodynamic stability equation. A linearized velocity solution for developing flow is used in the stability calculations. The numerically determined neutral stability results for the fully developed Couette flow are in excellent agreement with those of the analytical solution. The results presented here for Hartmann flow are believed to be more accurate owing to the more exact nature of the numerical solution.

Cholera is deadly watery diarrhea caused by Vibro cholerae. Approximately 550,000 Pakistani children die each year due to waterborne illnesses including diarrhea. Vibro cholera bacterium strain O1eLtOR is a major cause of diarrhea in Pakistan. Since it is a waterborne bacteria, people relying on tap water (not filtered) are the most vulnerable to this disease. In current study, tap water was disinfected by using different concentrations of sodium dichloroisocyanurate (NADDC) to devise an effective and inexpensive method to make water safe for drinking. Different concentrations of NADDC were utilized to disinfect water and 1.2 mg of NADDC in 40 ml water was effective to disinfect water from bacterial colonies The experimental data is represented through the proposed mathematical model i.e. exponential decay model and statistical analysis of the generated data is also done. The graphical representation is also done to show the exponential decay of bacterial growth. The results of our study reveal that NADCC is an effective chemical agent to purify drinking water from Vibrio cholerae.

Mid-wave and long-wave infrared (MWIR and LWIR) detection play vital roles in applications that include health care, remote sensing, and thermal imaging. However, detectors in this spectral range often require complex fabrication processes and/or cryogenic cooling and are typically expensive, which motivates the development of simple alternatives. Here, we demonstrate broadband (0.43-10 μm) room-temperature photodetection based on copper tetracyanoquinodimethane (CuTCNQ), a metal-organic semiconductor, synthesized via a facile wet-chemical reaction. The CuTCNQ crystals are simply drop-cast onto interdigitated electrode chips to realize photoconductors. The photoresponse is governed by a combination of interband (0.43-3.35 μm) and midgap (3.35-10 μm) transitions. The devices show response times (∼365 μs) that would be sufficient for many infrared applications (e.g., video rate imaging), with a frequency cutoff point of 1 kHz.

Nanofluids are the diluted interruptions of nano-sized particles in base fluid such as oil, ethylene glycol, water etc. Nanofluids have wide applications in industries because of their enhanced thermal properties. In present article, the stability analysis of MHD (Magneto-hydro-dynamic) Poiseuille flow of thermocapillary liquid layers of shear thinning nanofluids with oxide nanoparticles in base fluid (water) by imposing transverse magnetic field are studied. The oxide nanoparticles of Aluminum oxide (Al2O3), copper oxide (CuO), graphene oxide (GO), Iron oxide (Fe3O4), and titanium oxide (TiO2) are used. Numerical method used in current work is “cheybeshev collocation method”. To finding the eigenvalues from generalized Orr-sommerfeld equations, an algorithm named “QZ (Qualitat and Zuverlassigkeit)” used. The stability of different oxide nanoparticles based water nanofluids are compared and discussed through graphs. It has been found that Iron oxide based water nanofluid flow has more destabilizing effect and graphene oxide based water nanofluid flow has more stabilizing effect as compared to other oxide nanoparticles.

The primary objective of the present paper has been to understand the revolutionary concept of e-learning and the role that it is playing in imparting education to start-up entrepreneurs. The paper has deliberated on certain key aspects relating to e-learning modules like the e-learning components, e-learning advantages, and strategies for e-learning along with e-learning technology. The deliberation will also attempt to highlight the improvisation in academic achievement by the means of e learning. The expansion of e-learning into lessons could even catalyze the step towards the application of a grown-up learning hypothesis, within which instructors will no longer function primarily as substance merchants but will transform out as being gradually concerned as learning facilitators as well as capacity assessors.

Background: : Iron Oxide nanoparticles have enormous applications in environmental remediation and catalysis. The synthesis of such nanoparticles through a green approach provides a significant advantage due to the non-toxic nature of the ingredients involved. Method: : In the present work, Diospyros lotus fruit extract was used for the synthesis of iron oxide nanoparticles (NPs). The plant biomolecules were extracted employing two different solvents, i.e. water and methanol. The effect of both the extracts on the reduction of metal salt as well as on the shape and size of the produced NPs was investigated. Results:: UV-Visible spectroscopy confirmed the synthesis of iron oxide NPs, Fourier Transform Infrared (FTIR) spectrum depicted the presence of biomolecules on the surface of NPs as capping agents, X-ray Diffraction (XRD) diffractogram confirmed the crystalline structure of mixed iron oxide NPs and Scanning Electron Microscopy (SEM) images showed the spherical shape of NPs. The synthesized NPs were exploited to catalyze the degradation of methylene blue dye in the Fenton type catalytic reaction. The degradation reaction was monitored using UV-Visible spectroscopy, which indicated that the percent degradation increased from 15% (without iron oxide NPs) to 91% in the presence of organic extract prepared iron oxide NPs and to 81% in the presence of aqueous extract prepared iron oxide NPs. The effect of the concentration of methylene blue and iron oxide NPs on the degradation process was also investigated. Conclusion: : The results indicated the potential of synthesized nanoparticles to promote catalytic reactions involved in environmental remediation.

A pharmacophoric motif decorated with supramolecular functionalities (TZT) was designed for potential interaction with biological targets. Main insights of this work include the correlation of supra functionalities of TZT with its binding ability to proteins leading to the modulation of their structure and bioactivity as a promising perspective in the field of cellular protection from oxidative stress. To investigate the role of TZT in obliterating oxidative stress at a molecular level, its binding propensity with bovine serum albumin (BSA) and bovine liver catalase (BLC) was characterized using various biophysical methods. The binding constants of TZT with BSA (Kb = 2.09 × 105 M-1) and BLC (Kb = 2.349 × 105 M-1) indicate its considerable interaction with these proteins. TZT efficiently triggers favourable structural changes in BLC, thereby enhancing its enzyme activity in a dose dependent manner. The enzyme kinetics parameters of TZT binding to BLC were quantified using the Michaelis-Menten model. Both in silico and experimental results suggest that an increased substrate availability could be the reason for enhanced BLC activity. Furthermore, physiological relevance of this interaction was demonstrated by investigating the ability of TZT to attenuate oxidative stress. Treatment with TZT was found to mitigate the inhibition of A549 cell proliferation in the presence of high concentrations of vitamin C. This finding was confirmed at a molecular level by PARP cleavage status, demonstrating that TZT inhibits apoptotic cell death induced by oxidative stress.

The present work focused here is a mixed convective MHD flow of cross fluid in the presence of heat generation/absorption and variable thermal conductivity over a bidirectional stretchable sheet. To elaborate the mechanism of heat transfer is analyzed in view of non-Fourier heat flux based upon Cattaneo–Christov theory. The influence of a simple isothermal model of homogeneous–heterogeneous reactions is further used for solute concentration. As a result, the relevant Buongiorno fluid model is utilized in mathematical modeling and then it is simplified through lubrication technique. By using appropriate transformations, the raised PDEs initially converted to ODEs. Convergent solutions of ODEs are obtained by the implementation of the numerical procedure bvp4c technique. However, the velocity, temperature and concentration profiles have been sketched by distinct physical flow parameter. Drag coefficients and heat transport are also computed numerically. Our results reveal that temperature profile has an inverse relation between the relaxation parameter and variable thermal conductivity.

This paper presents a bi-level planning approach to find an optimal layout for a large-scale wind farm (WF) from economic and reliability perspectives. The upper level of the planning approach is formulated as constrained multi-objective optimization (MOO) to obtain the optimal WF layout, where two conflicting objectives are optimized simultaneously. Two objectives for MOO are i) yearly gross energy production and ii) annual loan repayment (for cable and land area of the WF), where the first objective is maximized and the second objective is minimized. Jensen's wake model is used to calculate the wake effect, and to evaluate the multiple wake effect within a WF, a coordinate-transformation-based approach has been adopted in this study. An efficient hybrid multi-objective metaheuristic algorithm, which is based on nondominated sorting multi-objective particle swarm optimization and improved archive multi-objective simulated annealing, has been proposed to find the optimized WF layout. The superiority of the Pareto front obtained by the proposed algorithm for the large-scale WF layout is supported by its comparison with different powerful and well-established MOO algorithms. In the lower level of the proposed approach, economic and reliability analyses of the solutions (WF layout), obtained in the Pareto front by the proposed hybrid algorithm, have been done. In this context, two performance metrics, a) generation economy index and b) expected wind energy generation (EWEG), have been considered. A sequential Monte Carlo simulation has been developed to calculate the EWEG considering random failure of both wind turbines and cables in this paper. The most suitable WF layout is selected by trading off between economy and reliability using a fuzzy decision-making approach.

The current industrial revolution signifies the high-value of biocatalysis engineering. Over the past decade, multiple micro- and nanostructured materials have been attempted for immobilization of enzymes to improve their catalytic properties. Conventional immobilization strategies result in improved stability, while insolubilized enzymes generally lost their activity compared to free counterparts. Recently, a new generation organic-inorganic hybrid nanoflowers with unique properties have received great attention as a novel and incentive immobilization approach owing to their simple fabrication, high biocatalytic efficiency, and enzyme stabilizing capability. The hybrid nanoflowers biocatalytic system implicates metal ions and biomolecules (enzymes). In contrast to free or conventionally immobilized enzymes, single enzyme or multi enzyme-incorporated flowers-like hybrid nanoconstructs demonstrated elevated catalytic activities and stabilities over a very broader range of experimental conditions, i.e., pHs, temperatures and salt concentration. This review discusses the recent developments in the fabrication strategies to diversifying nanoflowers, types, characteristics, and applications of organic-inorganic hybrid nanoflowers as a host platform to engineer different kinds of enzymes with requisite functionalities for biocatalysis applications in different sectors of the modern world. Based on experimental and theoretical literature data, the review is wrapped up with concluding remarks and an outlook in terms of upcoming challenges and prospects for their scale-up applications.

Silver nanoparticles (NPs) were synthesized using Diospyros lotus fruit extract. Plant biomolecules were extracted through two solvents i.e. water and methanol. Effect of both solvents on the extraction process as well as effect of both extracts on the reduction of precursor salt to NPs has been studied and reported. Employing the synthesized Ag NPs as a component of nanocomposites, hydrogel membranes were prepared with starch and polyvinyl alcohol (PVA). Synthesized Ag NPs as well as prepared nanocomposites membranes were fully characterized through FTIR, XRD, SEM and UV–Visible spectroscopy. The ultimate tensile strength of the hydrogel membranes with 50 ppm Ag NPs was found to be highest among all the compositions while swelling tendency of the membranes was found to increase with increase in the NPs concentrations. Additionally, no significant decrease in gel fraction of the hydrogel membranes could be observed with the addition of NPs. However, addition of NPs resulted in reduced water evaporation from the membranes. Finally, anti-bacterial test of the Ag NPs as well as hydrogel membranes showed comparable results as shown for the ciprofloxacin, indicating the potential of such membranes to be used in wound dressing application.

Mathematical modeling of cerebral tumor growth is of great importance in clinics. It can help in understanding the physiology of tumor growth, future prognosis of tumor shape and volume, quantify tumor aggressiveness, and the response to therapy. This can be achieved at macroscopic level using medical imaging techniques (particularly, magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI)) and complex mathematical models which are either diffusive or biomechanical. We propose an optimized generic modeling framework that couples tumor diffusivity and infiltration with the induced mass effect. Tumor cell diffusivity and infiltration are captured using a modified reaction-diffusion model with logistic proliferation term. On the other hand, tumor mass effect is modeled using continuum mechanics formulation. In addition, we consider the treatment effects of both radiotherapy and chemotherapy. The efficacy of chemotherapy is included via an adaptively modified log-kill method to consider tissue heterogeneity while the efficacy of radiotherapy is considered using the linear quadratic model. Moreover, our model efficiently utilizes the diffusion tensor of the diffusion tensor imaging. Furthermore, we optimize the tumor growth parameters to be patient-specific using bio-inspired particle swarm optimization (PSO) algorithm. Our model is tested on an atlas and real MRI scans of 8 low grade gliomas subjects. Experimental results show that our model efficiently incorporates both treatment effects in the growth modelingprocess. In addition, simulated growths of our model have high accuracy in terms of Dice coefficient (average 87.1%) and Jaccard index (77.14%) when compared with the follow up scans (ground truth) and other models as well.

In this work the electrochemical oxidation of methanol is studied on NiO based MOFs and its composites with reduced graphene oxides. NiO-MOF and its composites were prepared through hydrothermal method. The as-prepared materials were characterized by SEM, EDX, XRD, FTIR and Raman IR for their morphological and structural properties. The activity of prepared catalyst for oxidation of methanol was tested via cyclic voltammetry (CV) in an alkaline media on glassy carbon electrode. The electrochemical performance shows the effect of rGO concentration on methanol oxidation. The electro oxidation catalyzed by NiO-MOF and NiO-MOF/rGO composites exhibits a magnificent peak current density of 275.85 mA/cm2 at 0.8 V potential with a scan rate 50 mV/s making them a potential candidate for electrocatalysis.

In this paper, a novel wind farm control strategy is proposed to mitigate voltage dip induced frequency excursion in wind integrated power systems. In the proposed control strategy, conventional fixed reactive/active current injection priority is replaced by an optimum adaptive priority based reactive and active current injection. The control problem is formulated as a binary integer optimization problem, which simultaneously minimizes active power shortfall from wind generation during fault and complies with grid code requirements. Detailed wind farm model and wake effect are taken into consideration to achieve realistic response from the wind farm, while IEC 61400-27-1 wind turbine generator model is adopted for wind turbine modeling. Dynamic model of the test system has been developed in DIgSILENT PowerFactory, while the static model is also developed in MATLAB, and cosimulation platform has been used to test and validate the proposed control strategy. The proposed control strategy is applicable to variable speed wind turbine-based wind farm.

In conventional power systems, synchronous generators have been the main source of dynamic reactive power. However, displacement of conventional power plants by non-synchronous generation resources, such as wind power plants (WPPs) and other renewable energy sources, result in diminished dynamic reactive power reserve at system level. System operators in various countries are planning to tackle this issue by introducing dynamic reactive power reserve as a new ancillary service product. In this paper, reactive power capability of Type-4 wind turbine based WPP considering practical constraints is explored. A new and effective centralized WPP capability based control strategy is proposed to supply dynamic reactive power from a WPP, particularly, beyond grid code requirement. An adaptive method to dispatch reactive power from wind turbine generators (WTGs) in a WPP, is also proposed. In the presented study, wake effect and detailed WPP model are taken into consideration. The proposed strategy is implemented on three wind integrated benchmark power systems developed in DIgSILENT PowerFactory platform using IEC 61400–27–1 standard model of WTG.

The solution-based synthesis of the coordination polymer, CuTCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane), which exists in two phases, has predominately used acetonitrile (MeCN) as the solvent. However, our knowledge on the growth and properties of CuTCNQ in other solvents remains limited. In this work, the synthesis of CuTCNQ on Cu foil in two protic (MeOH, EtOH) as well as four aprotic (MeCN, DMSO, DMF, THF) solvents has allowed us to obtain new insights into the important role of the reaction medium in the spontaneous crystallization of CuTCNQ in discrete morphologies and phases. A new electrochemical method for phase identification also has been developed to support this study. Findings reveal that (i) the solvents with higher dielectric constants favor CuTCNQ crystallization; (ii) irrespective of the solvent, use of high temperature (60 °C vs. 25 °C in conventional synthesis) promotes CuTCNQ crystallization and facilitate conversion of phase I to phase II; (iii) phase I CuTCNQ possess enhanced redox catalysis (ferricyanide reduction by thiosulfate) performance over phase II CuTCNQ; and (iv) the amount of catalyst is not necessarily the most important factor for driving catalytic reactions, and other factors, such as, morphology, redox characteristics and solvent in which the CuTCNQ is synthesized may dictate the overall catalytic performance. These findings emphasize the importance of understanding the influence of parameters, such as, solvent and temperature in CuTCNQ synthesis as a means of providing materials with improved catalytic activity.

The last few decades have seen renewable energy source (RES) integration growing at a rapid pace and this trend is likely to continue. The displacement of conventional synchronous plant, particularly at higher RES shares, is resulting in a ‘lighter’ system with low system inertia and reduced governor droop stiffness, leading to increased vulnerability to fast frequency stability. This paper presents a review of literature from the research and industry communities on possible sources of non-synchronous fast frequency reserve, considered as a potential solution to address diminishing synchronous reserve in RES integrated systems. The wide range of potential sources includes wind turbines, solar photovoltaic plant, energy storage, high voltage direct current (HVDC) systems, and demand response. The challenges and limitations associated with each approach are highlighted, and alternative strategies to maintain a minimum volume of security constrained fast frequency reserve are discussed based on the recent industry trends.

This paper presents an accurate and realistic estimation of reactive power capability of solar photovoltaic (PV) inverters considering ambient temperature, solar irradiance, and terminal voltage. Based on the accurate estimation of reactive power capability, a self-adaptive voltage controller is proposed to enable solar PV power plant participation in voltage control ancillary service. The proposed accurate and realistic estimation has revealed the possibility of solar PV power plant failing to comply with grid code requirements under extreme weather conditions. On the other hand, the proposed control strategy has shown significantly better effectiveness to utilise solar PV inverter capability, and provide better voltage control support service to the grid.

Surface protein gp-120 of HIV-1 virus plays an important role in the infection of HIV-1, but detection of gp-120 during the early stage of infection is very difficult. Herein, we report a binding bioassay based on an RNA aptamer B40t77, which binds specifically to gp-120. The bioassay is built upon a hydrophobic glass slide with surface immobilized gp-120. When the glass surface is incubated in a solution containing B40t77, the aptamer is able to bind to gp-120 specifically and remove it from the surface after a short incubation time of 30 min. The result of the binding event can be amplified by using liquid crystal (LC) into optical signals in the final step. By using this bioassay, we are able to detect as low as 1 μg/ml of gp-120 with high specificity within 30 min. No response is obtained when gp-120 is replaced by other protein such as bovine serum albumin (BSA). This is the first qualitative bioassay which provides a simple way for the detection of gp-120 with the naked eye. The assay is robust, low-cost and does not require additional labeling. Thus, the bioassay is potentially useful for the early detection of HIV-1 in resources-limited regions.

The aim of the current study is to disclose the results of shape factor analysis of the flow of a hybrid nanofluid over a curved sheet. The flow is caused by a stretchable curved sheet. Mathematical modeling and analyses have been performed in the presence of curvature, melting heat and heterogeneous-homogeneous reactions. Autocatalysis and the coefficients of the reactant are dealt with in a similar manner. The physical properties of the fluid, including the fluid velocity, the heat and mass transfer properties, the skin friction and the Nusselt number have been acquired and analyzed under the influences of the dimensionless curvature, melting and heterogeneous–homogeneous reaction variables. Boundary layer approximations are used in the mathematical formulation. Suitable transformations have been used to transform differential equations into nonlinear ordinary differential equations. The resulting nonlinear system of equations has been analyzed via the matlab bvp4c solver. Comparisons of nanoliquids with the hybrid nanoliquid are presented through graphs and tables. The results of this analysis show that the skin friction and the heat transfer rate in the hybrid nanofluid are seen more prominently than those of the nanofluid for larger values of the curvature parameter [Formula: see text].

The facility layout problem (FLP) is a very important class of NP-hard problems in operations research that deals with the optimal assignment of facilities to minimize transportation costs. The quadratic assignment problem (QAP) can model the FLP effectively. One of the FLPs is the hospital facility layout problem that aims to place comprehensive clinics, laboratories, and radiology units within predefined boundaries in a way that minimizes the cost of movement of patients and healthcare personnel. We are going to develop a hybrid method based on discrete differential evolution (DDE) algorithm for solving the QAP. In the existing DDE algorithms, certain issues such as premature convergence, stagnation, and exploitation mechanism have not been properly addressed. In this study, we first aim to discover the issues that make the current problem worse and to identify the best solution to the problem, and then we propose to develop a hybrid algorithm (HDDETS) by combining the DDE and tabu search (TS) algorithms to enhance the exploitation mechanism in the DDE algorithm. Then, the performance of the proposed HDDETS algorithm is evaluated by implementing on the benchmark instances from the QAPLIB website and by comparing with DDE and TS algorithms on the benchmark instances. It is found that the HDDETS algorithm has better performance than both the DDE and TS algorithms where the HDDETS has obtained 42 optimal and best-known solutions from 56 instances, while the DDE and TS algorithms have obtained 15 and 18 optimal and best-known solutions out of 56 instances, respectively. Finally, we propose to apply the proposed algorithm to find the optimal distributions of the advisory clinics inside the Azadi Hospital in Iraq that minimizes the total travel distance for patients when they move among these clinics. Our application shows that the proposed algorithm could find the best distribution of the hospital’s rooms, which are modeled as a QAP, with reduced total distance traveled by the patients.

The ongoing pandemic of COVID-19 has shut down almost everything and it has become troublesome for smooth running of social life. The infections are increasing day by day. It is important to predict and forecast upcoming increase in infections to plan better. Predicting the possible spread can alert the COVID-19 fighters fighting from the front end as well as the common people. This study is about forecasting possible spread of COVID-19 in India using Exponential Smoothing technique and estimated spread based on Basic Reproduction Number (\(R_0\)). \(R_0\) is a sign of transmissibility of a virus. It represents the average number of new infections produced by an infectious person in a completely naive population. Also, this study has focused on forecasting the number of future infections to occur in various states of India. The forecasting and estimation has been carried out for 12 (Twelve) days from August 18, 2020 to August 29, 2020. These forecasted and estimated values show that Maharashtra will experience highest number of confirmed cases followed by Tamil Nadu, Andhra Pradesh, Uttar Pradesh, Delhi and West Bengal. Mizoram will experience least number of cases. This study can help the government and concerned authorities to make good work plan and prepare them for executing the same as per the requirement of states.

The techniques of data mining are used widely in the healthcare sector to predict and diagnose various diseases. Diagnosis of heart disease is considered as one of the very important applications of these systems. Data is being collected today in a large amount where people need to rely on the device. In recent years, heart disease has increased excessively and heart disease has become one of the deadliest diseases in many countries. Most data sets often suffer from extreme values that reduce the accuracy percentage in classification. Extreme values are defined in terms of irrelevant or incorrect data, missing values, and the incorrect values of the dataset. Data conversion is another very important way to preconfigure the process of converting data into suitable mining models by acting assembly or assembly and filtering methods such as eliminating duplicate features by using the link and one of the wrap methods, and applying the repeated discrimination feature. This process is performed, dealing with lost values through the "Remove with values" methods and methods of estimating the layer. Classification methods like Naive Bayes (NB) and Random Forest (RF) are applied to the original datasets and data sets with the feature of selection methods too. All of these operations are implemented on three various sets of heart disease data for the analysis of pre-treatment effect in terms of accuracy.

Renewable energy-driven displacement of synchronous generators leads to low system inertia which creates frequency stability issues in power system, thus necessitating system inertia estimation for secure and stable grid operation. However, one of the main challenges in system inertia estimation is frequency monitoring owing to the high cost associated with placing adequate number of measurement devices across the system. In this backdrop, a new approach for system inertia estimation with reduced number of frequency monitoring, however, without compromising estimation accuracy has been proposed in this paper. The frequency control areas depending on modal analysis based generator coherency are formed and single frequency measurement at each area determine system frequency response during grid disturbance, which in turn is used for system inertia estimation. The proposed approach of system inertia estimation has been implemented and validated on IEEE 39 bus system and Gujarat State grid developed in DIgSILENT PowerFactory simulation platform.

This work presents the preparation of an efficient and sensitive glucose sensor for the detection of glucose in an alkaline media. The glucose sensor is composed of a metal organic framework (MOF) composite comprising Ag@TiO2 nanoparticles. The hybrid of Ag@TiO2 encapsulated in ZIF-67 was synthesized by the solvothermal method and applied onto a glassy carbon electrode (GCE) for the non-enzymatic sensing of glucose. The porosity of ZIF-67 was favorable for the unhindered diffusion and entrapment of glucose and its cavities served as reaction vessels. The electrochemical behavior of Ag@TiO2@ZIF-67 showed amplified results when compared with that of Ag@TiO2 and ZIF-67. Cyclic tests toward the oxidation of glucose has demonstrated excellent stability of a MOF-based hybrid sensor. The sensor based on Ag@TiO2@ZIF-67 showed high sensitivity of 0.788 μAμM−1cm−2 with a linear concentration range of 48 μM−1 mM and a response time of 5 s with an excellent detection limit of 0.99 μM (S/N = 3).

Large scale deployment of various Renewable Energy Sources (RES) due to climatic issues and depletion of fossil fuels has led to significant RES generation share in power systems especially from Solar Photovoltaic (PV). Among the various challenges of higher solar PV integration, voltage and frequency stability issues are of major concern to the system operator. Voltage dip induced frequency excursions due to delayed active power recovery from the solar PV systems following a network fault is one such critical issue that has not been investigated enough and reported in the literature. This paper examines potential impact of such delayed active power recovery from utility scale solar PV systems, and its effect on the system frequency stability under increasing PV penetration levels. The studies have been carried out on modified New England Benchmark system and Gujarat state power system in India for various system scenarios and cases.

Suaeda maritima is a halophyte that has been evolutionary adapted to cope with saline and heavy metal conditions. The aim of the present study was to examine the biochemical response of Suaeda maritima against phytoextracting heavy metals and salts from paper mill effluent. Suaeda maritima seedlings have been grown for 120 days with an irrigation solution of 250 ml of 75% raw paper mill effluent after four drenching. Analysis of biochemical parameters revealed that maximum synthesis of chlorophyll, protein, phenol, proline and glycinebetaine may be involved in their ability to cope with heavy metal and salt stress. The present study confirms that the accumulation and increase of biochemical constituents can be considered as an efficient ROS scavenger and also maintain cellular homeostasis and metabolic functions in photosynthetically active leaves in Suaeda maritima, during phytoextraction studies. Keywords: phytoextraction, paper mill effluent, Suaeda maritima, biochemical, heavy metal and salts

Green syntheses of nanoparticles using plant materials are of tremendous scope. Here we report advantageous green synthesis for silver nanoparticles (AgNPs) using aqueous-root extract of Jurinea dolomiaea and AgNO3. Color change of solution and UV-Vis absorption at 444 nm indicated the formation of AgNPs. XRD confirmed their face centered cubic structure (fcc) with average particle size of 24.58 nm. SEM analysis showed their spherical, cubic and triangular structures. FT-IR indicated the presence of functional groups of reducing and stabilizing phytochemicals. Methanol-root extract of J. dolomiaea revealed high flavonoid (445 mg RE/g) and phenolic contents (92 mg GAE/g). Methanol-extract showed high antioxidant potency (IC50 = 0.494 μg/mL), rationally due to its high phenolic and flavonoid contents. These AgNPs showed the highest and equal antimicrobial activities against Escherichia coli and Pseudomonas aeruginosa (Inhibition zone 11.0 mm) whereas, methanol-roots extract showed equal and intermediate activities (Inhibition zone 8.0 mm) against both pathogens but aqueous extract showed poor activities (Inhibition zone 6.0 mm) against these both pathogens. AgNPs are playing a major role in the field of nanotechnology and nanomedicine due to their antimicrobial and drug delivery efficacy as well as reasonable tolerance in human biology.

Present study deals with Darcy Forhheimer application to CNTs nanofluid flow due to a cylinder and flat sheet. Thermal conductivity of CNTs nanofluid is inspected under renovated Hamilton-Crosser and Xue models. The solute concentration is regulated through a simple isothermal model of homogeneous-heterogeneous reactions. Thermodynamics processes of reactant and autocatalyst analyze the impact of temperature phase changes like evaporation or convection. It is considered that the base fluid (water) is essentially composed of SWCNT-Water (base fluid with SWCNT) and MWCNT-Water (base fluid with MWCNT). The solution of the problem is obtained by using implicit finite difference method (Keller-Box). It is unconditionally convergent and the well-tested extensively validated method. Influence of physically involved parameters are illustrated through graphs. Darcy Forhheimer parameters decline the fluid flow. The fluid velocity and thermal boundary layer thickness in case of flat sheet is higher when compared with stretching cylinder. Interestingly reverse outcomes are preserved for concentration. Homogeneous reaction parameter and Schmidt number have opposite trend on nanoparticle concentration. Higher curvature parameter is accounted for drag coefficient and heat transfer at the cylinder. Renovated Hamilton-Crosser model have larger thermal conductivity when compared with Xue model. Comparison of current result with previous result is given. The outcomes are found in an excellent agreement. Keywords: Keller box method, CNTs (SWCNT and MWCNT), Stretching cylinder and flat sheet, Renovated Hamilton-Crosser model, Xue model, Darcy Forhheimer law

This paper presents a new approach to select a suitable wind turbine (WT) for a wind farm (WF) site. In this approach, economy, reliability, resilience, and environmental aspects have been taken into account, as all the four aspects have a great deal of impact on the selection of a WT for a given site. Six commercially available WTs have been considered for this study. The energy output from a WF is significantly affected by wake, hence, in the proposed approach, placement of WTs in a WF is optimized using particle swarm optimization to reduce wake effect while increasing the energy production. A new algorithm has been proposed to find the reliability indices of the WF considering forced outage of WTs. In this context, two important reliability indices, such as expected energy not supplied and availability have been adopted to study the reliable viability of the optimized WF with all the six types of WTs. Power system resilience study has been gaining great deal of importance in recent times, but individual WF resilience study has not been addressed till now. This paper incorporates resilience as one of the criteria to select a suitable WT for any site. A new approach has been described in this regard to quantify the WF operational resilience by proposing an ideal resilience pentagon. The impact of all the six WTs on environment in terms of reduction of greenhouse gas emission has also been considered. Two different shaped WFs (same area) with same wind profile have been considered to study the proposed approach. A priority table has been formulated according to the ranking of WTs for different indices. The results show that the choice of WTs for WFs of different geometrical shape, however, with the same wind profile and the area may be different and largely depend on the choice of decision maker.

A target synthesis of selected biocompatible chiral Thiazolidine-4-carboxylic acid derivatives was attempted to investigate the influence of number, type and position of hydrogen bonding functionalities and solvent molecules in the crystal lattice on the supramolecular aggregation behaviour leading to formation of molecular assemblies. The single crystal X-ray diffraction studies of (R)-thiazolidine-4-carboxylic acid (T4CA, zwitter ion form), 2-propionyl T4CA and (2S,4R)-3-(tert-butoxycarbonyl)-2-(4-methoxyphenyl)T4CA and other reported thiozolidine 4-carboxylic acid derivatives were used to establish the solid state aggregation behaviour. The 1D, 2D and 3D agregrational behaviour of synthesized thiozolidine-4-carboxylic acid derivatives was explored from their crystal packing diagrams and was further extended in light of some appropriate literature reported thiozolidine-4-carboxylic acid derivatives. The explored 1D, 2D and 3D supramolecular aggregrational behaviour in case of the thiazolidine-4-carboxylic acid derivatives can be explored for their further applications as biocompatible supramolecular assemblies towards gas storage, biosensing and template catalysis.

The development of the process which can mitigate the drawbacks of catalytic esterification and handles high free fatty acid (FFA) containing oils is the highly focused area in biodiesel production...

Bimetallic sulfides have particle rich surface due to which they possess novel electrical, optical and magnetic properties. Current research has undertaken the synthesis of Nickel and Manganese dithiocarbamate complexes and complexes were incorporated in bimetallic form by combine decomposition. Combined FTIR peaks confirmed the bimetallic complex formation of Nickel and Manganese. UV–Vis absorption spectra of C10H20NiN2S4 expressed peak at 290 nm and C10H20MnN2S4 expressed peak at 317 nm. Furthermore, The UV–Vis peak for bimetallic composites Ni3S2/MnS2 was obtained at 340 nm. SEM exhibited the cubic shaped crystal structure of NiS/MnS composites. SEM were performed with the results confirming the synthesis of crystalline bimetallic sulfides/composites Ni3S2 and MnS2. Composite was utilized to make thin film by PVD assisted technique and band gap was 1.69 eV. Hence, it is suggested that composites Ni3S2 and MnS2 reveals promising prospect in lithium-ion batteries, supercapacitors and as an anode or cathode material for future applications.

In the present study, highly efficient catalysts based on corncob were synthesized for the esterification process. The synthesized catalysts were characterized by BET, XRD, and FT-IR. The effect of catalyst impregnation, carbonation, and sulfonation was studied in detail. The highest conversion of oleic acid (∼94.4%) was observed using a catalyst synthesized at H3PO4 impregnation ratio = 1 and time = 5 h; carbonization temperature = 723 K and time = 8 h; sulfonation temperature = 393 K and time = 15 h. Further, the performance of the catalyst was studied for the esterification of fatty acids (FAs) and free fatty acids (FFAs) present in Karanja oil. The catalyst showed ∼90% conversion of FAs/FFAs within 2 h at 338 K using a molar ratio of 1:10 (FA to methanol)/1:20 (Karanja oil to methanol) and a catalyst loading of 10 wt %. Furthermore, the reusability test of the catalyst revealed that it can be used for 20 times in a batch reactor to give ∼90% conversion of the oleic acid.

A simple, sensitive, selective and real time detection protocol was developed for Pb2+ ions in water using liquid crystals (LCs). In this method, NiFe2O4 nanoparticles were synthesized using chemical co-precipitation method. Crystallite size, morphological, functional groups and magnetization studies were confirmed using X-ray diffraction, Scanning Electron Microscopy, and Fourier transform infrared spectroscopy techniques, respectively. The nanoparticles were mono dispersed with average particle size of 20 ± 2 nm. The surfactant stabilized magnetic nanoparticles were incubated in liquid crystal based sensor system for the detection of Pb+2 ions. The bright to dark transition of LC was observed through optical microscope. When this system was further immersed with a solution containing Pb2+ ions, it caused homeotropic to planar orientation of LC. This interaction is attributed to the presence of abundant hydroxyl groups in such as M-OH, Fe-OH on the surface of spinel ferrites nanoparticles. These groups interact with metal ions at aqueous interface, causing disruption in LCs orientation giving bright texture. This sensor showed higher selectivity towards Pb2+ ions. The detection limit was estimated to be 100 ppb. The cheap and effective protocol reported here should make promising development of LC based sensor for lead ion detection. Keywords: Chemical co-precipitation method, Fourier transform infrared spectroscopy, Liquid crystals, Nanoparticles, Sensor, X-ray diffraction

Herein, we evaluate Quince seed hydrogel (QH) for the development of sustained release tablets (theophylline (THP) and diclofenac sodium (DS)) and some biomedical applications. Drug excipient compatibility and superporous morphology was witnessed by FTIR and scanning electron microscopy (SEM), respectively. Swelling of tablets was carried out in different media and results depicted high swelling indices of all tablet formulations in DI water, pH 6.8 and 7.4 while minor swelling was noticed in acidic buffer of pH 1.2. Swelling of these formulations followed second order kinetics. Salt responsive swelling was noted in NaCl and KCl solutions and found concentration dependent. Swelling/de-swelling behavior (on-off switching) of tablets was also carried out in buffer of pH 7.4 and pH 1.2, DI water and ethanol, DI water and normal saline. Drug release study from DS and THP tablet formulations was performed in DI water, pH 6.8 and 7.4. Drug release from matrix tablets was inversely proportional to QH concentration which followed the zero order kinetics and super case II transport mechanism. Haemocompatiblity studies of QH was also performed and found it non-haemolytic and non-thrombogenic. The results justified QH utility as a stimuli responsive and sustained release biomaterial for targeted drug delivery systems.