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Introduction: Overweight and obesity are rapidly increasing worldwide, posing a significant global health challenge. Medical students are at a higher risk of developing obesity due to factors such as a sedentary lifestyle, inadequate physical activity, unhealthy eating patterns, elevated stress levels, and the extensive amount of information they need to learn. The aim of this study was to find out the prevalence of overweight among medical students of a medical college., Methods: A descriptive cross-sectional study was conducted among medical students of a medical college from 5 October 2022 to 10 November 2022 after obtaining ethical approval from the Institutional Review Committee. Height in meters and weight in kilograms of students were measured to calculate body mass index. A convenience sampling method was used. The point estimate at a 95% Confidence Interval was calculated., Results: Among 261 medical students, 43 (16.47%) (11.97-20.97, 95% Confidence Interval) were overweight. Among them, 32 (74.41%) males and 11 (25.58%) females were overweight respectively., Conclusions: The prevalence of overweight among medical students is lower than in other studies done in similar settings., Keywords: body mass index; obesity; overweight; prevalence.

Feedstocks such as coal, biomass, plastics, and their blends have the potential to serve as fuels for the thermochemical conversion process owing to their relatively high calorific values. Nevertheless, the relative proportion of these feedstock blends has a pivotal influence over the overall energy conversion efficiency. Consequently, conducting a comprehensive study to optimize the blend proportion becomes crucial in order to obtain an optimal fuel. The study aims to investigate the thermochemical characterization and kinetics of blends composed of lignite coal, southern pine biomass, and municipal waste plastic blend to optimize the blend proportion. This optimization has been achieved through an analysis of 12 distinct blends, considering factors such as combustion reaction kinetics, combustion stability, and comprehensive combustion indices. The reaction kinetics, including activation energy, pre-exponential factor, and reaction order, were estimated using various methods, including Vyazovkin, Kissinger-Akahira-Sunose, Flynn-Wall-Ozawa, Master-plot, and multidistributed activation energy methods. The investigation revealed that increasing the biomass content within the blends enhances both the combustion stability and combustion performance. The multidistributed activation energy model exhibited a good fit with both the experimental thermogravimetric and the derivative thermogravimetric curves, achieving linear regression fitness values of 0.99 and 0.95, respectively. To showcase the viability of these blends as energy generation feedstock, the optimal blend comprised of 60% biomass, 10% coal, and 30% municipal waste plastic blend, possessing the lowest activation energy (110 kJ/mol), was employed as the feedstock for the fluidized bed oxy-steam gasification process. The gasification process resulted in a synthetic gas consisting of 47.79 mol % H 2 , 27.96 mol % CO, 5.85 mol % CH 4 , and 18.38 mol % CO 2 (nitrogen-free basis) with a cold gas efficiency of 72.88%. The findings of this study can offer valuable insights into global industries engaged in the thermochemical conversion of solid waste materials., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Introduction: Anaemia is one of the most common conditions which affects a significant proportion of pregnant women worldwide. These patients may have adverse effects on both the mother and the developing fetus. Detecting and timely treating anaemia in pregnancy help in the overall improvement of maternal and fetal health. The aim of the study was to find out the prevalence of low-birth-weight among term newborns born to anaemic pregnant women admitted to the Department of Obstetrics and Gynecology in a tertiary care centre., Methods: A descriptive cross-sectional study was conducted among pregnant women who were diagnosed with anaemia and admitted for delivery in the Department of Obstetrics and Gynecology after obtaining ethical approval from the Institutional Review Committee. Data was collected from 10 December 2022 to 10 March 2023. Convenience sampling method was used. The point estimate was calculated at a 95% Confidence Interval., Results: Among 300 newborns, the prevalence of low-birth-weight was 106 (35.33%) (29.92-40.74, 95% Confidence Interval). Among 106 newborn, 64 (60.37%) were male and 42 (39.62%) were female., Conclusions: The prevalence of low-birth-weight among newborns born to term anaemic pregnant women admitted to the Department of Obstetrics and Gynecology in a tertiary care centre was found to be higher than in studies done in a similar settings., Keywords: anaemia; infant; low birth weight; morbidity; pregnancy.

The exceptional photochromic and redox properties of polyoxometalate anions, PW 12 O 40 3- , have been exploited to develop an integrated photoelectrochemical energy storage cell for conversion and storage of solar energy. Elimination of strongly coordinating cations using benchtop ion soft landing leads to a ∼370% increase in the maximum power output of the device. Additionally, the photocathode displayed a pronounced color change from clear to blue upon irradiation, which warrants the potential application of the IPES cell in advanced smart windows and photochromic lenses.

Introduction: Central pontine myelinolysis is a type of osmotic demyelination syndrome, which involves damage to parts of brain most commonly pons. The most common causes include rapid correction of hyponatremia but other precipitating factors including alcoholism, diabetes, and chronic liver disease should also be considered., Case Presentation: We present a case of 44-year-old male with a history of chronic alcohol consumption, who presented in emergency room with complaints of slurring of speech and weakness of both upper and lower limbs. His MRI brain reveals 'trident-shaped' appearance with findings of High T2W/FLAIR signal noted in the pons with relative sparing of the periphery and hypo intense on T1W images. He was managed conservatively., Clinical Discussion: Proper diagnosis with MRI is needed for early detection so that proper intervention can be made on time., Conclusion: CPM can occur in the patient even if they are normonatremic or hyponatremic but can precipitate in Chronic Alcoholic patients., Competing Interests: The authors report no conflicts of interest., (© 2022 The Author(s).)

Introduction: Mesenteric venous thrombosis is due to blood clot in veins that drain blood from the intestine. It may lead to mesenteric ischemia. Protein S deficiency is one of the causes of superior mesenteric vein thrombosis., Case Presentation: A 47 years old male patient presented with pain in the abdomen. Contrast CECT shows filling defect in the superior mesenteric venous thrombosis. Coagulometer showed lower protein S activity than that of normal., Clinical Discussion: Proper diagnosis is needed for early detection so that proper intervention can be made on time. Anticoagulation and vitamin K antagonists are given., Conclusions: Though rare, protein S deficiency should be considered a possible cause of mesenteric venous thrombosis., Competing Interests: The authors report no conflicts of interest., (© 2022 The Authors.)

Appendicitis rarely presents with an left lower abdominal pain especially when the intestine is non-rotated or malrotated. Its diagnosis becomes quite troublesome to clinicians and delays prompt intervention. Non-rotation is the most common type of intestinal malrotation. Here, we present a case of a 40-year-old female with previously undiagnosed intestinal non-rotation with left lower abdominal pain and features of localised peritonitis. Abdominal ultrasonography and multidetector computerised tomography showed left-sided appendicitis with intestinal non-rotation. Diagnostic laparoscopy followed by explorative laparotomy and appendectomy was performed. Clinicians and surgeons are usually trained to diagnose and operate on right-sided appendix, thus, diagnosing and promptly intervening on left-sided appendicitis is quite challenging. Left-sided appendicitis must be kept in mind if a patient presents with left lower abdominal pain. Timely radiological scans like ultrasonography and computerised tomography scans help in prompt diagnosis in these cases., Keywords: appendicitis; case reports; peritonitis.

Introduction: Diffuse midline glioma with H3 K27M mutation is a new tumor entity from 2016 which is highly aggressive and classified as a WHO Grade IV tumor regardless of histopathologic features. DMG is an aggressive tumor with a poor prognosis, predominating in children and rarely in adults. The clinicopathologic features in adults remain poorly characterized., Case Presentation: Herein we report a case of a 28-year-old female with diffuse midline glioma with pathology confirmation of histone H3 K27M mutation presenting predominately with left upper and lower limb weakness for 3 weeks followed by an event of loss of consciousness and suspicious mass in MRI Brain/CT Brain. It was confirmed by immunoreactive H3K27M with a score of 4+ in neoplastic cells, which revealed Diffuse midline glioma, H3K27M mutant., Clinical Discussion: Diffuse midline glioma with histone H3-K27M mutation recently classified CNS tumor with grade IV, including both morphologic and molecular features for diagnosis and associated with poor prognosis., Conclusion: We report a case of adult diffuse midline glioma with H3K27M. The prognosis of diffuse midline glioma is poor and dependents solely on H3K27M irrespective of its grade and characteristics. A comprehensive study of diffuse midline glioma on clinical, radiographic, and demographic features in adult is needed., Competing Interests: The authors report no conflicts of interest., (© 2022 The Authors.)

Introduction: Primary dysmenorrhea is one of the most common gynecological problems among adolescent females. It is defined as painful menses in women with normal pelvic anatomy, usually beginning during adolescence. This study aims to find out prevalence of self-medication practice in primary dysmenorrhea among medical and nursing undergraduate students., Methods: A descriptive cross-sectional study was conducted in a tertiary care hospital from November 2020 to March 2021 after taking ethical approval from the Institutional Review Committee. Convenient sampling technique was used. A total of 269 female medical and nursing students with complaints of dysmenorrhea were enrolled and the remedial methods used by them such as self-medication, medical advice and home remedies for dysmenorrhea were asked using an online questionnaire delivered to participants. Data analysis was done in the Statistical Package of Social Sciences. Point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data., Results: Self-medication practice for dysmenorrhea was reported in 175 (65%) of students. The prevalence of mild or moderate pain was commonly present in age group 21-25 years. commonly used for self-medication was mefenamic acid 121 (48%), followed by ibuprofen 51 (20.3%) and paracetamol 41 (16.3%)., Conclusions: Self- medication practice among medical and nursing undergraduate students is high despite awareness of adverse effects.

We describe a simplified approach to simulating Raman spectra from ab initio molecular dynamics (AIMD) calculations. The protocol relies on on-the-fly calculations of approximate molecular polarizabilities using the well-known sum over orbitals (as opposed to states) method. This approach bypasses the more accurate but computationally expensive approach to calculating molecular polarizabilities along AIMD trajectories, i.e., solving the coupled perturbed Hartree-Fock/Kohn-Sham equations. We demonstrate the advantages and limitations of our method through a few case studies targeting molecular systems of interest to surface- and/or tip-enhanced Raman spectroscopy practitioners.

Tip-enhanced Raman (TER) spectral images of 4-thiobenzonitrile-coated Au nanorods map the spatial profiles and trace the resonances of dipolar and multipolar plasmonic modes that are characteristic of the imaged particles. For any particular rod, we observe sequential transitions between high-order modes at low frequency shifts and lower-order modes at higher frequencies. We also notice that higher-order modes (up to m = 4) are generally observed for long rods as compared to their shorter analogues, where longitudinal dipolar resonances ( m = 1) are observable. In effect, this work adds a new dimension to local optical field mapping via TERS, which we have previously explored. Not only can the magnitudes, vector components, local/nonlocal characters of local optical fields be imaged through molecular TERS, but spatially varying local optical resonances are also direct observables.

A series of optical and electron microscopies are utilized in concert to unravel the properties of corrugated metallic tips. While the overall microscopic shapes of the tips dictate their optical resonances and plasmonic field enhancement factors, nanometric structural details govern their tip-enhanced Raman (TER) spectra and images. Using 4-thiobenzonitrile (TBN) as a molecular reporter, spatially resolved TER spectra reveal that optical rectification and molecular charging are among the prominent observables in the tip-tip TER geometry. We show the spurious appearance of anions is driven by highly localized resonances that appear as a result of surface corrugation and their manifestation throughout the course of TER nanospectroscopy complicates spectral assignments. Overall, nanoscale spatial variations in the TERS spectra suggest that the tip-tip geometry sustains junction plasmons that appear very different from what may be expected from the hybridization of the bulk tip resonances.

We record nanoscale-resolved chemical images of thiobenzonitrile (TBN)-functionalized smooth gold nanospheres on silicon via tip-enhanced Raman (TER) nanospectroscopy. The recorded images trace the nascence of the familiar doughnut-shaped scattering profile of nanoparticles on silicon at its origin (the particle surface), which appears as a horseshoe-shaped scattering pattern under our experimental conditions. The local optical field maps are in agreement with their simulated finite-difference time-domain analogues. Analysis of the recorded spectra with the aid of ab-initio -molecular-dynamics-based Raman spectral simulations further suggests that optical rectification and molecular charging take place throughout the course of atomic-force-microscopy-based TER nanoscale chemical imaging.

Plasmonic tip-sample junctions, at which the incident and scattered optical fields are localized and optimally enhanced, are often exploited to achieve ultrasensitive and highly spatially localized tip-enhanced Raman scattering (TERS). Recent work has demonstrated that the sensitivity and spatial resolution that are required to probe single molecules are attainable in such platforms. In this work, we observe and rationalize comparable TERS from few-layer WSe 2 single crystals exfoliated onto Au- and Cr-coated Si substrates, using a plasmonic TERS probe excited with a 638 nm laser. Our experimental observations are supported by finite-difference time-domain simulations that illustrate that the attainable field enhancement factors at the Au-Au and Au-Cr tip-sample junctions are comparable in magnitude. Through a combined experimental and theoretical analysis, we propose that besides Au/Ag, several metallic substrates may be used to record bright TERS spectral images.

Molecular reorientation dynamics modulate the physical and chemical properties of molecules at interfaces. This is particularly the case for organic molecules interacting with metallic surfaces-structural motifs of current interest to ultrasensitive chemical/biological detection/imaging. In this context, surface-enhanced Raman scattering (SERS) can be used to gauge the orientation of molecules in the immediate vicinity of plasmonic metals. Herein, we analyze SERS spectra of two aromatic thiols (4-mercaptobenzonitrile and thiophenol) chemisorbed onto silver substrates using ab initio molecular dynamics-based Raman spectral simulations that account for the optical response of molecules in the bulk and oriented molecules at the surface. Through a comparison with prior works aimed at gauging the orientation of our two model systems on metallic substrates, we describe the advantages and discuss the limitations of our described models and approach to gauging the orientation of molecules on metals through time domain simulations of their SERS signatures.

Not all regions of optical field nanolocalization and enhancement are suitable sites for chemical transformations on plasmonic metals. We illustrate the concept using chemically functionalized monocrystalline gold platelets in aqueous solution imaged using a Au-coated tip-enhanced Raman scattering (TERS) probe. For our proof-of-principle study, we select a model plasmon-driven chemical process, namely, the dimerization of p-nitrothiophenol (NTP) to dimercaptoazobenzene. Consistent with recent observations from our group, we find that TERS maps at vibrational resonances corresponding to NTP trace the optical fields that are maximally enhanced toward the edges of the platelets. Conversely, simultaneously recorded product maps reveal that the dimerization process occurs only at specific sites on our substrate. Given the uniformity of the structures and local optical fields at the edges of the gold platelets, our results suggest that molecular crowding and steric effects play a key role in our case of plasmon-driven NTP dimerization at the gold-water interface.

We image 4-mercaptobenzonitrile-functionalized silver nanowires (∼20 nm diameter) through tip-enhanced Raman scattering (TERS). The enhanced local optical field-molecular interactions that govern the recorded hyperspectral TERS images are dissected through hybrid finite-difference time-domain density functional theory simulations. Our forward simulations illustrate that the recorded spatiospectral profiles of the chemically functionalized nanowires may be reproduced by accounting for the interaction between orientationally averaged molecular polarizability derivative tensors and enhanced incident/scattered local fields polarized along the tip axis. In effect, we directly map the enhanced optical fields of the nanowire in real space through TERS. The simultaneously recorded atomic force microscopy (AFM) images allow a direct comparison between our attainable spatial resolution in topographic (13 nm) and TERS (5 nm) imaging measurements performed under ambient conditions. Overall, our described protocol enables local electric field imaging with few nm precision through molecular TERS, and it is therefore generally applicable to a variety of plasmonic nanostructures.

Nonequilibrium chemical phenomena are known to play an important role in single molecule microscopy and spectroscopy. Herein, we explore these effects through ab initio molecular dynamics (AIMD)-based Raman spectral simulations. We target an isolated aromatic thiol (thiobenzonitrile, TBN) as a prototypical molecular system. We first show that the essential features contained in the ensemble-averaged Raman spectrum of TBN can be reproduced by averaging over 18 short AIMD trajectories spanning a total simulation time of ∼60 ps. This involved more than 90 000 polarizability calculations at the B3LYP/def2-TZVP level of theory. We then illustrate that the short trajectories (∼3.3 ps total simulation time), where the accessible phase space is not fully sampled, provide a starting point for understanding key features that are often observed in measurements targeting single molecules. Our results suggest that a complete understanding of single molecule Raman scattering needs to account for molecular conformational flexibility and nonequilibrium chemical phenomena in addition to local optical fields and modified selection rules. The former effects are well-captured using the described AIMD-based single molecule Raman spectral simulations.

Tip-enhanced Raman spectroscopy (TERS) is particularly sensitive to analytes residing at plasmonic tip-sample nanojunctions, where the incident and scattered optical fields may be localized and optimally enhanced. However, the enhanced local electric fields in this so-called gap-mode TERS configuration are nominally orthogonal to the sample plane. As such, any given Raman active vibrational eigenstate needs to have projections (of its polarizability derivative tensor elements) along the sample normal to be detectable via TERS. The faint TERS signals observed from two prototypical systems, namely, pristine graphene and graphene oxide are a classical example of the aforementioned rather restrictive TERS selection rules in this context. In this study, we demonstrate that nanoindentation, herein achieved using pulsed-force lithography with a sharp single-crystal diamond atomic force microscope probe, may be used to locally enhance TERS signals from graphene and graphene oxide flakes on gold. Nanoindentation locally perturbs the otherwise flat graphene structure and introduces out-of-plane protrusions that generate enhanced TERS. Although our approach is nominally invasive, we illustrate that the introduced nanodefects are highly localized, as evidenced by TERS nanoscale chemical mapping. As such, the described protocol may be used to extend and generalize the applicability of TERS for the rapid identification of two-dimensional material systems on the nanoscale.

Tip-enhanced Raman scattering (TERS) can be used to image plasmon-enhanced local electric fields on the nanoscale. This is illustrated through ambient TERS measurements recorded using silver atomic force microscope tips coated with 4-mercaptobenzonitrile molecules and used to image step edges on an Au(111) surface. The observed two-dimensional TERS images uniquely map electric fields localized at Au(111) step edges following 671 nm excitation. We establish that our measurements are not only sensitive to spatial variations in the enhanced electric fields but also to their vector components. We also experimentally demonstrate that (i) few nanometer precision is attainable in TERS nanoscopy using corrugated tips with nominal radii on the order of 100-200 nm, and (ii) TERS signals do not necessarily exhibit the expected E 4 dependence. Overall, we illustrate the concept of electric field imaging via TERS and establish the connections between our observations and conventional TERS chemical imaging measurements.

Fluorescence spectroscopy was employed to characterize the kinetics of guest exchange in diblock copolymer micelles composed of poly(ethylene oxide-b-ε-caprolactone) (PEO-PCL) diblock copolymers in water/tetrahydrofuran (THF) mixtures which encapsulated fluorophores. The solvent composition (THF content) of the micelle solution was varied as a means of modulating the strength of interactions between the fluorophore and solvent as well as between the micelle core and solvent. A donor-acceptor fluorophore pair was employed consisting of 3,3'-dioctadecyloxacarbocyanine perchlorate (DiO, the donor) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI, the acceptor). Through the process of Förster resonance energy transfer (FRET), energy was transferred from the donor to acceptor when the fluorophores were in close proximity. A micelle solution containing DiO was mixed with a micelle solution containing DiI at t = 0, and the emission spectra of the mixed solution were monitored over time (at an excitation wavelength optimized for the donor). In micelle solutions containing 5 and 10 vol% THF in the bulk solvent, an increase in the acceptor peak intensity maximum occurred over time in the post-mixed solution, accompanied by a decrease in the donor peak intensity maximum, indicating the presence of energy transfer from the donor to the acceptor. At long times, the FRET ratios (acceptor peak intensity divided by the sum of the acceptor and donor peak intensities) were indistinguishable from that determined from pre-mixed micelle solutions of the same THF content (in pre-mixed solutions, DiO and DiI were encapsulated within the same micelle cores). In the micelle solution containing 20 vol% THF, the fluorophore exchange process occurred too quickly to be observed (the FRET ratios measured from the solutions mixed at t = 0 were commensurate to that measured from the pre-mixed solution). A time constant describing the guest exchange process was extracted from the time-dependence of the FRET ratio through fit of an exponential decay. An increase in the THF content in the micelle solution resulted in a decrease in the time constant, and the time constant varied over five orders of magnitude as the THF content was varied from 5-20 vol%.

Scanning tunneling microscopy was used to make the first molecular scale measurements of the temperature dependence of composition of an adlayer at the solution-solid interface. We conclusively demonstrate that metal porphyrins adsorb very strongly on Au(111) at the solution solid interface such that the monolayer composition is entirely kinetically controlled below about 100 °C. The barrier for desorption is so great in fact that a temperature of 135 °C is required to induce desorption over a period of hours. Moreover, cobalt(II) octaethylporphyrin (CoOEP) and NiOEP desorb at different rates from different sites on the surface. We have measured the rate constant for desorption of CoOEP into phenyloctane to be 6.7 × 10(-5)/s at 135 °C. On the basis of these measurements, an upper bound can be set for the desorption rate of NiOEP into phenyloctane as 6.7 × 10(-4)/s at 135 °C. For solutions of the order of 100 μM in NiOEP or CoOEP, a dense monolayer is formed within seconds, and the adsorption rate constants fall within 40% of each other. The structures of NiOEP and CoOEP monolayers are essentially identical, and the molecular spacing for both can be described by A = 1.42 ± 0.02 nm, B = 1.32 ± 0.02 nm, and α = 57° ± 2°. The solubility of CoOEP and NiOEP in phenyloctane at room temperature was measured to be 0.228 and 0.319 g/L, respectively.

For the first time, the pressure and temperature dependence of a chemical reaction at the solid/solution interface is studied by scanning tunneling microscopy (STM), and thermodynamic data are derived. In particular, the STM is used to study the reversible binding of O(2) with cobalt(II) octaethylporphyrin (CoOEP) supported on highly oriented pyrolytic graphite (HOPG) at the phenyloctane/CoOEP/HOPG interface. The adsorption is shown to follow the Langmuir isotherm with P(1/2)(298K) = 3200 Torr. Over the temperature range of 10-40 °C, it was found that ΔH(P) = -68 ± 10 kJ/mol and ΔS(P) = -297 ± 30 J/(mol K). The enthalpy and entropy changes are slightly larger than expected based on solution-phase reactions, and possible origins of these differences are discussed. The big surprise here is the presence of any O(2) binding at room temperature, since CoOEP is not expected to bind O(2) in fluid solution. The stability of the bound oxygen is attributed to charge donation from the graphite substrate to the cobalt, thereby stabilizing the polarized Co-O(2) bonding. We report the surface unit cell for CoOEP on HOPG in phenyloctane at 25 °C to be A = (1.46 ± 0.1)n nm, B = (1.36 ± 0.1)m nm, and α = 54 ± 3°, where n and m are unknown nonzero non-negative integers.