Saxena, Deepak Kumar

Data collection in resource-constrained environments, particularly in the Global South, is challenging for a variety of philosophical, theoretical, methodological, and ethical reasons. Challenges may involve using research approaches designed in the Global North that are not appropriate when using data from the social and cultural contexts in the Global South. Adopting a reflective approach, this paper examines research projects in Bangladesh, Malawi, Sierra Leone, and Rwanda and highlights the challenges encountered on these projects. Along with the problems, attempted ameliorations are discussed, and insights are offered on how the authors overcame these challenges. The paper posits that these challenges can be mitigated by adopting contextualist methodology resulting in theories that are based on local social and cultural processes. The paper proposes that a critical realist-philosophical approach and methodology are appropriate because of contextual specificity and the innate ability to alleviate problems associated with the Global North methodology and generalisable theory.

The present study aims to investigate the motional dynamics of risperidone within polylactic co-glycolic acid (PLGA) microsphere by employing solution state 1H and 19F nuclear magnetic resonance (NMR) measurements. Risperidone, a second-generation fluorinated antipsychotic drug used for the treatment of schizophrenia is commercially marketed as PLGA microsphere formulation resulting in prolonged release of the drug in solution. Although the current trend in the pharmaceutical market is to develop drug formulation with long-acting release (LAR) products, complete physicochemical characterization of such formulations are scarce. Especially the effects of microsphere encapsulation on the motional properties and diffusion behavior of the drugs are not discussed adequately in any of the earlier reports. We therefore, have employed NMR relaxation and diffusion measurements to decipher the interaction of PLGA cavity water with risperidone. A detailed analysis of NMR relaxation rates confirmed the event of encapsulation and the presence of local motion in the non-fluorinated end of risperidone. Further, the relaxation data indicated a significant alteration in 19F chemical shift anisotropy (CSA) and CSA/dipole-dipole (DD) cross-correlated relaxation mechanism and decreased effect of solvent relaxation pointing out reduced water concentration within the microsphere cavity. 1H and 19F diffusion coefficients of risperidone led to the information about hydrodynamic radius of risperidone in free and encapsulated states. Measurement of hydrodynamic radius supported the presence of limited water in PLGA cavity allowing higher translational mobility of risperidone after the encapsulation.

In order to get the nanocomposite of silver-doped resin, we treated aniline with dil. HCl and formaldehyde solution (40%) with constant stirring and got polymer metal complex, then we calcinated this complex at 9000 C in Muffle furnace for 45 min. The structure and chemical properties of Ag-doped resin were confirmed byIH NMR and IR spectroscopic techniques. The morphological study of this decomposed polymer metal nanocomposite had been done by SEM, AFM and TEM. Polymer nanocomposites of metals represent an important field for fundamental studies which offer a wide range of engineering and biomedical applications. The prepared polymer Ag-doped aniline formaldehyde nanocomposites are widely used as photosensitive components, catalysts, photo-catalyst and in surface enhanced Raman spectroscopy as well as chemical analysis.

Emeraldine Hydrochloride salt is coated on copper substrate and studied for hydrogen storage and hydrogen evolution reaction in 1 M NaOH. Phenomenological thermodynamic approach demonstrated elsewhere in conjunction with the cyclic voltammetry data is employed to calculate the solvent modified work function for polyaniline coated copper in alkaline medium as −0.65 eV. The solvated work function is in satisfactory agreement with the band gap difference of π−π* transition in emeraldine base and π- polaron transition in emeraldine salt ca −0.6 eV as reported in the literature. 13C and 1H NMR studies revealed that polyaniline undergoes switching between emeraldine salt and emeraldine base, before and after hydrogen evolution respectively. The volume of hydrogen evolved on polyaniline coated copper is 1.64 times than that on copper as demonstrated by Gas chromatography. Thus emeraldine salt, when stored in NaOH act as hydrogen storage medium and upon electrochemical perturbation can release hydrogen at controlled rate depending on the scan rate employed.

This work presents the dynamic modeling and analysis of a particle-reinforced and prestressed electro-magneto-viscoelastic plate actuator. The actuator belongs to a smart actuator category and is made of an electro-magneto-Active polymer filled with a particular volume fraction of suitable fillers. An energy-based electro-magneto-viscoelastic model is developed to predict the actuator response and interrogate the impact of particle reinforcement on the dynamic oscillations of a pre-stressed condition of the actuator. An Euler-Lagrange equation of motion is implemented to deduce the governing dynamic equation of the actuator. The findings of the model solutions provide preliminary insights on the alteration of the nonlinear behavior of the actuator driven by DC and AC dynamic modes of actuation. It is observed that the enrichment in the particle reinforcement characterized by the amount of fillers strengthens the polymer and depleted the associated level ofdeformation. Also, the depletion in the intensity of oscillation and enhancement in the frequency of excitation is perceived with an increase in the particle reinforcement. In addition, the time-history response, Poincare plots, and phase diagrams are also plotted to assess the stability, periodicity, beating phenomenon, and resonant behavior of the actuator. In general, the current study provides initial steps toward the modern actuator designs for various futuristic applications in the engineering and medical field. [DOI: 10.1115/1.4051911].

Digital transformation (DT) has presented tremendous opportunities and challenges to organisations. By leveraging continuously emerging digital technologies, organisations are increasingly pursuing to make their business models efficient and smart. Consequently, research on DT has gained significant momentum in academia and practice. Although many studies present insights about DT as a phenomenon, the underlying factors encouraging such transformations are not frequently evaluated and discussed, and less so in Indian context. This study addresses this research gap by conducting a multiple case study of six organisations engaged in DT and identifying primary reasons driving the organisations towards DT. These factors are broadly classified into four categories – business innovation and process improvement, business sustainability, internal digital aspirations, and unplanned external exigencies. The study empirically identifies the drivers of DT that beginner organisations can use to address ‘where to start for DT’. The well-established organisations can use these drivers as a baseline to assess, contextualise and strategise their DT efforts to improve the success rates of their DT endeavours.

In this report, our main focus is to introduce a set of one-dimensional (1D) NMR methods based on chemical shift, relaxation, and magnetization transfer, namely, NOE and chemical exchange involving selective pulse excitation to study the solution dynamics of drug in free and encapsulated state within polymeric microsphere. In this regard 5-fluorouracil (5-FU) loaded poly lactic-co-glycolic acid (PLGA) microspheres are prepared as model system via standard water-in-oil-in-water emulsification method. One-dimensional 1H and 19F nuclear magnetic resonance (NMR) spectra of 5-FU in presence of PLGA microspheres presented a significant change in linewidth and relaxation rates compared with free 5-FU confirming encapsulation. Furthermore, loss of coupling pattern in 1H and 19F NMR of PLGA encapsulated 5-FU as compared with free 5-FU suggests an enhanced –NH and –H2O protons exchange dynamics in the interior of the microsphere indicating hydrated microsphere cavity. Quantification of exchange dynamics in case of free and PLGA-encapsulated 5-FU was attempted employing 1D selective NOESY and 1D multiply selective inversion recovery experiments. Analysis of the exchange rates confirmed existence of more than one kind of water population within the cavity as mentioned in an earlier solid state NMR report.

UNS S32101 lean duplex stainless steel (DSS) has a two phase microstructure consisting of austenite and ferrite in near equal proportions. Aging at high temperature results in formation of σ phase reducing ductility and also corresponding depletion of Cr from the matrix. The effect of long term aging on the microstructure and mechanical properties is still an active area of research for lean DSSs. In the present work effect of aging at 750 °C (up to 480 h) on microstructure and mechanical properties has been systematically studied. Scanning electron microscopy (SEM) revealed that the precipitates were distributed along ferrite/austenite (δ/γ) interfaces and ferrite/ferrite (δ/δ) boundaries. Nitrides (mainly Cr2N) were observed in initial phases of aging and σ phase afterwards, mostly at longer aging times. The decrease of Ni and Mo and increase in N in UNS S32101 steel delayed the precipitation of σ, but could not avoid it completely. The room temperature absorbed impact energy of specimens decreased gradually as the aging time increased. The lowest value of absorbed impact energy was found to be 24 ± 2 J after 480 h of aging, which was only ~11% as that of solution annealed specimen. Fractography also showed that the fracture morphology changed from fibrous (ductile) to dominant brittle (which involved predominance of cleavage facets along with long, wide cracks i.e. delamination fracture) with increasing aging time. Tensile tests also showed a decrease in ductility and an increase in yield stress/ultimate tensile strength with aging time.

Organisations, including public service organisations, are increasingly adopting a digital transformation strategy, and deploying digital capabilities to enhance customer experience. However, digital initiatives in public services often focus more on the technology with relatively less regard to the citizen for whom the services are designed. To address this lacuna, this study contextualises the digital transformation of public services by focusing on the citizen. This study is based on data collected in the conduct of two projects involving public services within an EU member state. Based on the analysis of the citizen-journey in availing of public services, five common pain-points are identified - information inconsistencies, intricate website navigation, bureaucratic jargon, disconnected multichannel touchpoints, and a lack of real-time online support. To alleviate the pain-points, the authors offer five insights based on academic insights and international benchmarking.

The present study aims to comprehend the adsorption behavior of a set of anticancer drugs namely 5-fluorouracil (5-FU), doxorubicin and daunorubicin on ZnO nanoparticles (ZnO NPs) proposed as drug delivery systems employing solid state (ss) NMR, FTIR and Cyclic Voltammetry (CV) analysis. FTIR and 1H MAS ssNMR data recorded for bare ZnO nanoparticle confirmed the presence of adsorbed –OH groups on the surface. 13C CP-MAS NMR spectra recorded for free and ZnO surface adsorbed drug samples exhibited considerable line broadening and chemical shift changes that complemented our earlier report on UV-DRS and XRD data of surface adsorption in case of 5-FU. Moreover, a remarkable enhancement of 13C signal intensity in case of loaded 5-FU was observed. This clearly indicated rigid nature of the drug on the surface allowing efficient transfer of 1H polarization from the hetero nitrogen of 5-FU to ZnO to form surface hydroxyl (–OH) groups and the same has been observed in the quantum chemical calculations. To further analyze the motional dynamics of the surface adsorbed 5-FU, longitudinal relaxation times (T1) were quantified employing Torchia method that revealed significant enhancement of 13C relaxation rate of adsorbed 5-FU. The enhanced rate suggested an effective role of quadrupolar contribution from 67Zn to the 13C relaxation mechanism of ZnO_5-FU. The heterogeneous rate constant (khet), average free energy of activation (∆G≠) and point of zero charge (PZC) measured for free and drug loaded ZnO NPs samples using CV further support the SS-NMR results.