Strain relaxation in monolayer MoS2 over flexible substrate.

In this communication, we demonstrate uniaxial strain relaxation in monolayer (1L) MoS2 transpires through cracks in both single and double-grain flakes. Chemical vapour deposition (CVD) grown 1L MoS2 has been transferred onto polyethylene terephthalate (PET) and poly(dimethylsiloxane) (PDMS) substrates for low (∼1%) and high (1-6%) strain measurements. Both Raman and photoluminescence (PL) spectroscopy revealed strain relaxation via cracks in the strain regime of 4-6%. In situ optical micrographs show the formation of large micron-scale cracks along the strain axis and ex situ atomic force microscopy (AFM) images reveal the formation of smaller lateral cracks due to the strain relaxation. Finite element simulation has been employed to estimate the applied strain efficiency as well as to simulate the strain distribution for MoS2 flakes. The present study reveals the uniaxial strain relaxation mechanism in 1L MoS2 and paves the way for exploring strain relaxation in other transition metal dichalcogenides (TMDCs) as well as their heterostructures.

Electrodiffusioosmosis induced negative differential resistance in micro-to-millimeter size pores through a graphene/copper membrane.

Negative differential resistance (NDR) is one of the nonlinear transport phenomena in which ionic current decreases with the increase in electromotive potential. Electro-osmosis, diffusio-osmosis, and surface charge density of pores are the driving forces for observing NDR in nanoscale ion transport. Here, we report electrodiffusioosmosis induced NDR using micro to millimeter size pores in a two-dimensional (2D) graphene-coated copper (Gr/Cu) membrane. Along with NDR, we also observed ion current rectification (ICR), in which there is preferential one-directional ion flow for equal and opposite potentials. The experimentally observed NDR effect has been validated by performing ion transport simulations using Poisson-Nernst-Planck (PNP) equations and Navier-Stokes equations with the help of COMSOL Multiphysics considering salinity gradient across the membrane. Charge polarization induced electro-osmotic flow (EOF) dominates over diffusio-osmosis, causing the backflow of low concentration/conductivity solution into the pore, thereby causing NDR. This finding paves the way toward potential applications in ionic tunnel diodes as rectifiers, switches, amplifiers, and biosensors.

Overlimiting current near a nanochannel a new insight using molecular dynamics simulations.

In this paper, we report for the first time overlimiting current near a nanochannel using all-atom molecular dynamics (MD) simulations. Here, the simulated system consists of a silicon nitride nanochannel integrated with two reservoirs. The reservoirs are filled with [Formula: see text] potassium chloride (KCl) solution. A total of [Formula: see text] million atoms are simulated with a total simulation time of [Formula: see text] over [Formula: see text] 30000 CPU hours using 128 core processors (Intel(R) E5-2670 2.6 GHz Processor). The origin of overlimiting current is found to be due to an increase in chloride ([Formula: see text]) ion concentration inside the nanochannel leading to an increase in ionic conductivity. Such effects are seen due to charge redistribution and focusing of the electric field near the interface of the nanochannel and source reservoir. Also, from the MD simulations, we observe that the earlier theoretical and experimental postulations of strong convective vortices resulting in overlimiting current are not the true origin for overlimiting current. Our study may open up new theories for the mechanism of overlimiting current near the nanochannel interconnect devices.

Crystallographic investigation, Hirshfeld surface analysis, NLO characterization and experimental spectral (UV and NMR) studies with DFT probe on(R)-9-(2-hydroxy propyl)adenine.

In this study, (R)-9-(2-hydroxy propyl)adenine (HPA) is the molecule of interest for investigation. The XRD from single crystal of HPA has been used to extract its structural features. Since HPA crystallised in a non-centro symmetric space group P212121, its NLO property was studied and it was found to exhibit very good SHG activity. To explore the intermolecular interactions the generated Hirshfeld surface has been investigated along with 2D-fingerprint plots. The experimental electronic and NMR spectra taken in the UV-visible and radio frequency regions respectively for HPA have been corroborated in correlation with theoretical predictions at Density Function Theory using 6-311++g (d, p) basis set. The experimental XRD geometrical parameters, chemical shifts of 13C and 1H and λmax values of HPA fit satisfactorily with the corresponding theoretically obtained numerical values as well as the stimulated spectrograms with the experimental ones. Further to explore the electronic structure, the MESP surface has been generated and investigated. The thermodynamic, kinetic and chemical reactivity features have been explored by means of frontier molecular orbitals of HPA.

Crystallographic, spectral and computational studies on (S)-4-(4-aminobenzyl) oxazolidin-2-one.

The experimental geometry (XRD), vibrational (IR and Raman), electronic (UV-visible) and NMR spectra of (S)-4-(4-Amino-benzyl)-oxazolidin-2-one (ABO) have been corroborated with the corresponding first principle calculated values at DFT using hybrid B3LYP exchange correlation functional invoking 6-311++g(d, p) basis set. The optimized geometrical parameters were found to be in satisfactory agreement with the experimental values obtained from the X-ray diffraction structural features of ABO. The scaled down computed vibrational frequencies with appropriate scaling factors were in good correspondence with the experimental observations. Room-temperature 1H and 13C nuclear magnetic resonance (NMR) studies were supported by advanced density functional theory calculations. The theoretical spectrograms of FT-IR, FT-Raman, 1H NMR, 13C NMR and UV of the title compound have been constructed and compared with experimental spectra and Hirshfeld surface analysis has also been made to study the intermolecular interactions. The electronic structure of the title compound has also been studied in terms of HOMO, LUMO and MESP diagrams.

Evaluation of a polymorphism in MYBPC3 in patients with anthracycline induced cardiotoxicity.

Cardiotoxicity is the most serious side effect of anthracyclines (doxorubicin, daunorubicin or epirubicin). The incidence of anthracycline induced late cardiac toxicity (AIC) that is overt clinically is 3-5% in the Indian population. Polymorphism in intron 32 (deletion of 25bp) of MYBPC3 has been shown to be present exclusively in Asians and more so in South India (3-8%). The frequency of the polymorphism is significantly higher (13%) in patients with cardiomyopathy in India. Fifteen patients were identified to have cardiac dysfunction following treatment for malignant lymphoma with doxorubicin containing regimens. Peripheral blood DNA from control, amplified by polymerase chain reaction yielded a 467bp fragment while in the presence of the 25bp deletion only a 442bp fragment was detected. To confirm the presence or absence of the polymorphism, amplified DNA was restricted using Bgl1 in all samples. Bgl1 restricted amplified DNA only if the 25bp deletion was absent. A 467 base pair band was observed in all the 15 samples, which suggested the absence of polymorphism in MYBPC3. In a sample of DNA from a patient with a deletion in exon 33 (confirmed by sequencing) a 442bp fragment was detected. Amplified DNA from this patient was not restricted with Bgl1. Wild type MYBPC3 when amplified gave a distinct restriction banding pattern consisting of two bands of 401bp and 66bp. Amplified DNA from all peripheral blood samples restricted with Bgl1 suggesting the absence of the polymorphism. In this preliminary report, MYBPC3 does not seem to play a role in anthracycline induced cardiotoxicity.

A Clinicopathological Study of Various Oral Cancer Diagnostic Techniques.

Oral cancer is one of the most commonly occurring malignant tumors in the head and neck regions with high incident rate and mortality rate in the developed countries than in the developing countries. Generally, the survival rate of cancer patients may increase when diagnosed at early stage, followed by prompt treatment and therapy. Recently, cancer diagnosis and therapy design for a specific cancer patient have been performed with the advanced computer-aided techniques. The responses of the cancer therapy could be continuously monitored to ensure the effectiveness of the treatment process that hardly requires diagnostic result as quick as possible to improve the quality and patient care. This paper gives an overview of oral cancer occurrence, different types, and various diagnostic techniques. In addition, a brief introduction is given to various stages of immunoanalysis including tissue image preparation, whole slide imaging, and microscopic image analysis.

Pterygoid Implant for Atrophic Posterior Maxilla.

Replacement of missing teeth in the posterior maxilla is always a challenge for the treating implant surgeon as the posterior maxilla has several obstacles in the form of quality, quantity, the anatomy of the maxillary sinus, and inaccessibility. To overcome these deficiencies, several surgical procedures such as sinus lift, bone augmentation, tilted implants, short implants, and zygomatic implants were tried. Since these procedures have their own limitations, pterygomaxillary region provides us an excellent place for placement of implant and rehabilitation of posterior maxilla. This case report describes the usage of the pterygomaxillary region for placement of the implant to restore atrophic posterior maxilla, without any additional surgical procedures.

Rehabilitation of Anterior Maxilla with Dental Implants in Periodontally Compromised Patient.

Although implant is the treatment of choice for rehabilitation of patients with aggressive periodontitis, it is also challenging for the dentists. There are various views about success of implant therapy for these patients. Few authors have proposed that aggressive periodontitis patients have less success rate of implant survival, while many authors have shown successful management of aggressive periodontitis patients with implants. For implants to be successful in these patient, it is important to control the periodontal disease before placement of implants. Thus a multidisciplinary approach is essential for successful rehabilitation of these patients. This case report aims at discussing the periodontal management and implant rehabilitation in a patient with aggressive periodontitis.

Management of gingival recession with acellular dermal matrix graft: A clinical study.

AIMS AND OBJECTIVES: Obtaining root coverage has become an important part of periodontal therapy. The aims of this studyare to evaluate the clinical efficacy of acellular dermal matrix graft in the coverage of denuded roots and also to examine the change in the width of keratinized gingiva. MATERIALS AND METHODS: A total of 20 sites with more than or equal to 2 mm of recession depth were taken into the study, for treatment with acellular dermal matrix graft. The clinical parameters such as recession depth, recession width, width of keratinized gingiva, probing pocket depth (PD), and clinical attachment level (CAL) were measured at the baseline, 8th week, and at the end of the study (16th week). The defects were treated with a coronally positioned pedicle graft combined with acellular dermal matrix graft. RESULTS: Out of 20 sites treated with acellular dermal matrix graft, seven sites showed complete root coverage (100%), and the mean root coverage obtained was 73.39%. There was a statistically significant reduction in recession depth, recession width, and probing PD. There was also a statistically significant increase in width of keratinized gingiva and also gain in CAL. The postoperative results were both clinically and statistically significant (P < 0.0001). CONCLUSION: The results of this study were esthetically acceptable to the patients and clinically acceptable in all cases. From this study, it may be concluded that acellular dermal matrix graft is an excellent substitute for autogenous graft in coverage of denuded roots.

Chlorhexidine varnish implemented treatment strategy for chronic periodontitis: A clinical and microbial study.

AIM: The aim of the present study was to evaluate the short-term clinical and microbiological effect of chlorhexidine varnish when used as an adjuvant to scaling and root planing in the treatment of chronic periodontitis. MATERIALS AND METHODS: A split-mouth design was conducted in 11 patients suffering from chronic periodontitis. The control site underwent scaling and root planing, and the experimental site was additionally treated with chlorhexidine varnish application. Clinical parameters, namely, gingival index (GI), plaque index (PI), bleeding on probing (BoP), probing pocket depth (PPD), and clinical attachment level were recorded at baseline, 1 month, and 3 months postoperatively. Furthermore, microbial examination of the plaque samples was done at baseline, 1 month, and 3 months. RESULTS: Both treatment strategies showed significant improvement in GI, PI, BoP, PPD, and clinical attachment level, at both follow-up visits by comparison with baseline levels. At study termination, chlorhexidine varnish implemented treatment strategy resulted in additional improvement in the clinical parameters, and more reduction in the total anaerobic count at 1 month and 3 months. CONCLUSIONS: These findings suggest that a chlorhexidine varnish implemented treatment strategy along with scaling and root planing may improve the clinical outcome for the treatment of chronic periodontitis in comparison to scaling and root planing alone.

Massive expanding hematoma of the chin following blunt trauma.

Posttraumatic hematoma of the face is common and usually self-limiting in nature. We report an unusual massive expanding hematoma of the chin within 9 h following a blunt trauma with no associated injuries or fracture.

An in vitro-in vivo correlation study of modified release formulations of Venlafaxine. HCl / An in vitro-in vivo correlation study of modified release formulations of Venlafaxine. HCl

A single dose, randomized, complete and four treatment cross over study was conducted in healthy human subjects for IVIVC of venlafaxine.HCl, Plasma concentrations were estimated by a simple, rapid, sensitive and validated LCMS method, Cetirizine was used as the internal standard (IS), The analytes and the IS were extracted from the human plasma by liquid?liquid extraction technique, The reconstituted samples were chromatographed on Kromasil C18 column using an isocratic solvent mixture [acetonitrile?water, 90:10 (v/v)] at a flow rate of 0.5 mL/min, Method validation was performed as per FDA guidelines and the results met the acceptance criteria, USP dissolution apparatus I (Basket) and pH 6.8 at 100 rpm was found to yield acceptable IVIVC for the drug, The developed dissolution method would discriminate bioinequivalent batches, A ?Level A? correlation was observed for the selected formulations at the in vitro dissolution conditions developed, The dissolution method predicted the best absorption rate for the selected modified release formulations, The validity of the correlation was assessed by determining how well the IVIVC model could predict the rate and the extent of absorption as characterized by Cmax and AUC, A percent prediction error of = 10 % for C max and AUC obtained establishes the predictability of the developed IVIVC model, It may, therefore, be concluded that the developed dissolution method can surrogate for human bioequivalence study.

Room temperature synthesis and optical studies on Ag and Au mixed nanocomposite polyvinylpyrrolidone polymer films.

Optical properties of silver, gold and bimetallic (Au:Ag) nanocomposite polymer films which are prepared by chemical method have been reported. The experimental data was correlated with the theoretical calculations using Mie theory. We adopt small change in the theoretical calculations of bimetallic/mixed particle nanocomposite and the theory agrees well with the experimental data. Polyvinylpyrrolidone (PVP) was used as reducing and capping agent. Fourier transform infrared spectroscopy (FTIR) study reveals the presence of different functional groups, the possible mechanism that leads to the formation of nanoparticles by using PVP alone as reducing agent. Optical absorption spectra of Ag and Au nanocomposite polymers show a surface plasmon resonance (SPR) band around 430 and 532 nm, respectively. Thermal annealing effect on the prepared samples at 60 °C for different time durations result in shift of SPR band maximum and varies the full width at half maximum (FWHM). Absorption spectra of Au:Ag bimetallic films show bands at 412 and 547 nm confirms the presence of Ag and Au nanoparticles in the composite.

Isolation and evaluation of a polysaccharide from Prunus amygdalus as a carrier for transbuccosal delivery of Losartan potassium.

An oral buccoadhesive drug delivery system for Losartan potassium using a hydrophilic polysaccharide, isolated from Prunus amygdalaus (Badam gum), was developed and evaluated for its potential to overcome the drawbacks associated with the conventional drug therapy. The results of the study indicate that the isolated polysaccharide has good physicochemical and morphological characteristics and is suitable for use as a mucoadhesive sustain release polymer in pharmaceutical dosage forms, to alleviate the drawbacks of the conventional drug therapy of Losartan potassium.

Effect of deposition of Ag on TiO2 nanoparticles on the photodegradation of Reactive Yellow-17.

Nanoparticles of TiO(2) were synthesized by sol-gel technique and the photodeposition of about 1% Ag on TiO(2) particles was carried out. Ag-deposited TiO(2) catalyst was characterised by XRD, TEM and UV-vis spectroscopy. The Ag-TiO(2) catalyst was evaluated for their photocatalytic activity towards the degradation of Reactive Yellow-17 (RY-17) under UV and visible light irradiations. Then the results were compared with synthesized nano-TiO(2) sol and P-25 Degussa and the enhanced degradation was obtained with Ag-deposited TiO(2). This enhanced activity of Ag-TiO(2) may be attributed to the trapping of conduction band electrons. The effect of initial dye concentration, pH and electron acceptors such as H(2)O(2), K(2)S(2)O(8) on the photocatalytic activity were studied and the results obtained were fitted with Langmuir-Hinshelwood model to study the degradation kinetics and discussed in detail.