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In the present era of data-driven architectures like 5G, Internet of things (IoT), Artificial Intelligence (AI), etc, the requirement of fast-switchable memory storage is more than ever. Oxide resistive switches are considered to be a primary choice in the non-volatile memory design. In this work, we have engineered the conventional metal-insulator-metal (MIM) structure of an oxide memristor (Ag/ZnO/ITO) by inducing an additional oxide layer La0.7Sr0.3MnO3 (LSMO) at the interface between the active layer (ZnO) and Ag electrode. The presence of LSMO acts as a reservoir for the oxygen vacancies, easing the conducting filament formation process in ZnO, thereby enabling drastic improvement of the switching performance and offering reliable endurance over multiple switching cycles. First-principles-based calculations suggested the role of Oxygen vacancies in controlling the electronic state of ZnO and formation of vacancies in the resistive switching process, which is in agreement with the experimental observation. The current results pave ways for improving the switching performance of resistive memory circuits through simple structural engineering incorporation, which lies at the heart of oxide electronics.

The present study is a part of hard rock aquifer of Telangana, South India, where the groundwater is withdrawn heavily for drinking, irrigation, and small-scale industrial purposes. Geochemical characteristics explain the chemical processes, which control the groundwater chemistry and consequently the groundwater quality, while the chemical quality of groundwater is adversely affected by anthropogenic activities, which damage the water environment. The focus of the present study was, thus, to know the origin of geochemical characteristics and also to evaluate the quality of groundwater for various purposes for taking the suitable remedial measures to provide safe water to the local community. Geochemical relations (GR) and hierarchical cluster analysis (HCA) were used to assess the geochemical characteristics. Entropy weighted groundwater quality index (EWGQI), United States Soil Salinity Laboratory Staff (USSLS)’s diagram, and groundwater quality criteria for water supply pipes (GQCW) were used to evaluate the groundwater quality for drinking, irrigation, and industrial purposes, respectively. The study found that the water-rock interactions associated with ion exchange and evaporation were the prime geochemical factors controlling the geochemical characteristics and the anthropogenic activities as the secondary factor. These observations were further supported by HCA. According to the EWGQI, 34.97% of the spatial area was found to have the poor and very poor groundwater quality zones for drinking purpose, because of the dominance of TDS, Na+, Cl−, $$ {\mathrm{SO}}_4^{2-} $$ , $$ {\mathrm{NO}}_3^{-} $$ , and F− contents in the groundwater system. Based on the USSLS’s diagram, 79.55% of the present study area was observed to be poor and very poor water quality type for irrigation utilization due to salinity hazard. The GQCW demonstrated that the 7.91% and 8.82% of the areas were not suitable for industrial purpose due to influence of incrustation based on $$ {\mathrm{HCO}}_3^{-} $$ and $$ {\mathrm{SO}}_4^{2-} $$ , respectively, and 1.85%, 12.32%, and 1.25 of the areas are unfit due to influence of corrosion based on pH, TDS, and Cl−, respectively. Therefore, boiling, activated carbon filter, rainwater harvesting, suitable coatings on metal surfaces of water supply pipes, etc. are the important suggested effective strategic measures to provide safe water for drinking, irrigation, and industrial purposes.

Evaluation of seasonal and spatial variations in vulnerable zones for poor groundwater quality is essential for the protection of human health and to maintain the crop yields. With this objective, groundwater samples were collected seasonally (i.e., pre- and post-monsoon) from the Yellareddygudem watershed of Telangana, India. These samples were analysed for major chemical parameters (pH, TDS, Ca2+, Mg2+, Na+, K+, [Formula: see text], Cl-, [Formula: see text], [Formula: see text], and F-). Geographical information system (GIS) tools were used to delineate the seasonal and spatial variations for vulnerable zones related to the drinking groundwater quality index (DGQI) and irrigation groundwater quality index (IGQI). Geochemical facies and relations, Piper diagrams, and principal component analysis indicated that the weathering, dissolution, leaching, ion exchange, and evaporation were the primary processes controlling the groundwater quality seasonally. Human influences were the secondary factors. The TDS, Na+, K+, Cl-, [Formula: see text], and F- parameters were observed to be within the drinking water quality standard limits in most post-monsoon groundwater samples. However, the DGQI showed an increase in the number of samples with unsuitable quality for drinking in the post-monsoon period compared with the pre-monsoon period. The IGQI demonstrated that the number of samples with unsuitable quality for irrigation increased in the post-monsoon period compared to the pre-monsoon period. The differences in the vulnerable zones between the pre- and post-monsoon periods were due to variations in groundwater recharge, following the topography. Thus, the present study will help decision makers to plan groundwater treatment measures within vulnerable zones.

Background Researchers have struggled to understand the natural history of lesions presenting with both lichenoid features and epithelial dysplasia. Thus the present study was designed to differentiate between OLP, OLP with dysplasia, epithelial dysplasia and epithelial dysplasia with lichenoid features based on the expressions of ki-67, p53, COX-2, and α-SMA. Materials and methods Formalin-fixed paraffin-embedded archival specimens of OLP, OLP with dysplasia, epithelial dysplasia and epithelial dysplasia with lichenoid features were subjected to immunohistochemical staining with ki-67, p53, COX-2, and α-SMA. Results Ki-67 exhibited strong positivity in 100% (6/6) of epithelial dysplasia cases, 71.4% (5/7) of lichenoid dysplasia cases, 57.1% (4/7) of OLP cases and 60% (3/5) of OLP with dysplasia cases. Strong p53 staining was evident in more cases of lichenoid dysplasia [42.8% (3/7)], while moderate staining was more frequent in OLP cases [42.8% (3/7)] and OLP with dysplasia cases [42.8% (3/7)] and mild intensity was more frequent in epithelial dysplasia cases [50% (3/6)] followed by lichenoid dysplasia cases [42.8% (3/7)], OLP cases [28.5 (2/7)] and OLP with dysplasia cases [40% (2/5)]. COX-2 strong positivity was more frequent in cases of epithelial dysplasia cases [57.1% (4/7)] and OLP [50% (3/6)]. Strong α- SMA staining was noted more frequently in lichenoid dysplasia cases [71.4 (5/7)], followed by OLP cases [42.8% (3/7)] and OLP with dysplasia cases [60% (3/5)]. Conclusions Ki-67, p53, α-SMA and COX-2 expression do not differentiate between OLP, LP with dysplasia and epithelial dysplasia with lichenoid features.

Extraction of roads from high-resolution aerial images with a high degree of accuracy is a prerequisite in various applications. In aerial images, road pixels and background pixels are generally in the ratio of ones-to-tens, which implies a class imbalance problem. Existing semantic segmentation architectures generally do well in road-dominated cases but fail in background-dominated scenarios. This paper proposes a dense refinement residual network (DRR Net) for semantic segmentation of aerial imagery data. The proposed semantic segmentation architecture is composed of multiple DRR modules for the extraction of diversified roads alleviating the class imbalance problem. Each module of the proposed architecture utilizes dense convolutions at various scales only in the encoder for feature learning. Residual connections in each module of the proposed architecture provide the guided learning path by propagating the combined features to subsequent DRR modules. Segmentation maps undergo various levels of refinement based on the number of DRR modules utilized in the architecture. To emphasize more on small object instances, the proposed architecture has been trained with a composite loss function. The qualitative and quantitative results are reported by utilizing the Massachusetts roads dataset. The experimental results report that the proposed architecture provides better results as compared to other recent architectures.

The present study is a part of hard rock aquifer of Telangana, South India, where the groundwater is withdrawn heavily for drinking, irrigation, and small-scale industrial purposes. Geochemical characteristics explain the chemical processes, which control the groundwater chemistry and consequently the groundwater quality, while the chemical quality of groundwater is adversely affected by anthropogenic activities, which damage the water environment. The focus of the present study was, thus, to know the origin of geochemical characteristics and also to evaluate the quality of groundwater for various purposes for taking the suitable remedial measures to provide safe water to the local community. Geochemical relations (GR) and hierarchical cluster analysis (HCA) were used to assess the geochemical characteristics. Entropy weighted groundwater quality index (EWGQI), United States Soil Salinity Laboratory Staff (USSLS)'s diagram, and groundwater quality criteria for water supply pipes (GQCW) were used to evaluate the groundwater quality for drinking, irrigation, and industrial purposes, respectively. The study found that the water-rock interactions associated with ion exchange and evaporation were the prime geochemical factors controlling the geochemical characteristics and the anthropogenic activities as the secondary factor. These observations were further supported by HCA. According to the EWGQI, 34.97% of the spatial area was found to have the poor and very poor groundwater quality zones for drinking purpose, because of the dominance of TDS, Na

Evaluation of seasonal and spatial variations in vulnerable zones for poor groundwater quality is essential for the protection of human health and to maintain the crop yields. With this objective, groundwater samples were collected seasonally (i.e., pre- and post-monsoon) from the Yellareddygudem watershed of Telangana, India. These samples were analysed for major chemical parameters (pH, TDS, Ca

Phosphorene has a unique set of characteristics such as a semiconducting nature, good carrier mobility and low-spin orbit coupling aspects which makes it a highly prospective two dimensional material for cross-hybrid architectures in nanoelectronics, spintronics, and optoelectronics. In the spintronic context, the creation of a stable magnetic order in phosphorene can be immensely beneficial for designing phosphorene spin circuits. In this work, we present high efficiency spin filtering behaviour in magnetically rendered phosphorene. First, we calculate the effect of doping various 3d block elements in phosphorene to introduce a stable magnetic order. Next, by varying doping concentrations in distinct doping configurations, an extensive phase diagram has been obtained depicting the presence of various electronic and magnetic states. This allows us to achieve a high magnetisation in the presence of various transition metal atoms, with a spin polarisation of ∼100% in half-metallic regimes. The transport behaviour reveals a map of the spin injection efficiency showing enhancement with doping concentration and reaching a perfect spin filtering capacity of ∼100% in the presence of Ti, Cr, Mn, Co, and Fe atoms. The present results offer new insights into engineered designs of multi-functional phosphorene spintronic circuits.

We investigate the magnetic and thermoelectric properties of α-MnO2 synthesized using the hydrothermal route. The nanorod structure having an aspect ratio of ∼10 is recorded using FESEM image. The magnetization vs temperature curves reveals the ferromagnetic like ordering below a magnetic transition temperature (∼28 K) which is also confirmed from the hysteresis curve at 10 K. The coercivity in the sample was observed to be 2.9 kOe and remnant magnetization was observed as 0.34 emu/g. Thermoelectric measurements reveal the n-type conduction in the system with a Seebeck coefficient of ∼160 µV/K, the electrical conductivity of ∼42 S/m and the thermal conductivity of 0.65 W/m-K at 300 K.

LaCoO3 shows interesting thermoelectric properties due to the existence of different charge states along with different spin states of cobalt in the system. Substitution at La and Co site leads to tune the electrical conductivity and hence Seebeck coefficient. We show that spark plasma sintered (SPS) La0.7Sr0.3Mn0.5Co0.5O3 sample shows an increase in the value of electrical conductivity at higher temperature with nominal decrease in the Seebeck coefficient. This improves the figure of merit for La0.7Sr0.3Mn0.5Co0.5O3 polycrystalline sample at 800 K. The maximum figure of merit for SPS La0.7Sr0.3Mn0.5Co0.5O3 is 0.006 at 800 K.

This paper proposes a robust framework for quality restoration of remotely sensed aerial images. Proposed framework works in three steps: (1) Efficient color balancing and saturation adjustment, (2) Efficient color restoration, (3) Modified contrast enhancement using particle swarm optimization (PSO). In order to show the robustness, step-wise results of proposed framework is illustrated. Several aerial images from two publically available datasets are tested to support the robustness of the proposed framework over existing image quality restoration methods. The experimental results of proposed framework and other existing quality restoration methods are compared in terms of NIQMC, BIQME, MICHELSON, DE, EME and PIXDIST along with visual experimental results. Based on experimental results conducted on several aerial images suggest that the proposed framework is outperform over existing quality restoration methods.

Aim The aim of the study was to report a unique case of glandular odontogenic cyst (GOC) in an unusual location of anterior maxilla. Materials and methods Considering the age, sex, and location of the lesion, a minimally invasive surgical procedure was opted considering esthetics, such as decompression followed by enucleation and fresh frozen bone (FFB) grafting. To arrive at the diagnosis, cytokeratin (CK)-19 was employed to differentiate from suspected intraosseous mucoepidermoid carcinoma. Results With the evidence of pre- and post treatment histopathological changes, the lesion appeared less aggressive justifying the treatment executed. Conclusion Glandular odontogenic cyst is a locally aggressive jaw cyst, which has a high rate of cortical perforation and recurrence that poses both diagnostic and therapeutic challenges. Clinical significance Treatment of decompression, followed by enucleation may be considered as an effective option in comparison to aggressive surgical intervention. How to cite this article Kumari K, Sowmya SV, Vineeth K, Rao RS, Lalitha RM, Augustine D, Haragannavar VC, Nambiar S, Abraham M. Staged Minimally Invasive Surgical Approach in the Management of Glandular Odontogenic Cyst. World J Dent 2018;9(1):48-52.

Andaman and Nicobar Islands, the gastropod diversity is high, due to the majority of shores are rocky. The wet rocky shore promotes algal growth, which is ultimate for feeding ground for gastropod growth and development leading to more diversity. The global warming, anthropogenic activities, industrial and domestic pollution, etc., have accelerated the loss of coastal and marine biodiversity components over the last few decades which has been of great concern. However, except global warming, the other factors were of least concern with reference to Andaman and Nicobar Islands biodiversity due to a pristine environment. Therefore, exploration of biodiversity in these islands is essential to create a baseline data for record and future research. Four locations of south to north Andaman Islands which represented Carbyns Cove from south Andaman, Rangat and Mayabunder from the Middle Andaman and Diglipur from the North Andaman were selected for this study. Gastropoda species were collected for a period of one year in three prevailing seasons of Andaman and Nicobar Islands. They are South West Monsoon (SW monsoon), North East Monsoon (NE Monsoon) and Non Rainy Seasons (NR Seasons). The present study of gastropods distribution in the South, Middle and North Andaman groups of Islands suggested that there are 71 species belonging to 52 genus and 33 families. At any one of the time and any one of the locations, only one occurrence was noticed for 38 species and remaining 33 species were overlapping with respect to stations and seasons. Evaluation of the cluster suggested that Cluster A (NR season in Carbyns Cove) and Cluster B (NE and SW Monsoon in Mayabunder) as a separate entity among the 12 combinations of stations and seasons due to their species representation. It was also concluded that out of 71 studied species, 3 species were not reported till date in these Island environment and 2 species from any other parts of India.

In this work, we report the temperature-dependent transport and resistive switching behaviour of a promising hybrid structure made of La0.7Ca0.3MnO3 (LCMO) and reduced graphene oxide (rGO). The current-voltage (IV) characteristics are non-linear across the studied temperature range of 100 K–300 K, which is also temperature-dependent. The memristive effect is most prominent at 200 K, while the reduction of hysteresis in the IV-curve with decrease in temperature is ascribed to the low thermal energy of the charge carriers. The charge transport in the SET and RESET process at different temperatures can be explained using trap-controlled space charge limited conduction mechanism for temperature > 200 K and Poole-Frenkel emission at temperatures below that.

In this study, we reported the presence of robust, reversible unipolar electric pulse-induced resistance switching effects in copper iodide and La0.7Sr0.3MnO3 nanocomposites. The properties of the resistive switching and change in the I–V pattern was analyzed over 100 cycles by hysteretic pulse current–voltage measurement (pulse width = 0.01 s and pulse period = 0.02 s). The charge transport analysis of various regions of the 1st cycle pointed towards Schottky emission and Poole–Frenkel effect to be the dominant mechanisms in lower bias region and higher bias region respectively. On the other hand, resistive switching turned out to be stable over 1000 cycles of square electrical pulse train measurement where frequency of 125 Hz (pulse period 2 ms and pulse width 100 μ s ) and 250 Hz (pulse period 1 ms and pulse width 50 μ s ) were used.

The present investigation carried out from a rural part of Nalgonda district, Telangana, India was to know the general groundwater quality and also to measure the vulnerable zones of non-cancer-causing health risks with respect to infants, children, and adults due to the consumption of nitrate and fluoride contaminated groundwater. Groundwater samples were collected from the study area and analyzed for the major physicochemical parameters. Nitrate and fluoride contents ranged from 2 to 700 mg/L and 0.3 to 4.7 mg/L, in which 59.09% and 31.82% of the groundwater samples exceed the safe drinking water limits of 45 mg/L and 1.5 mg/L, which spread over an area of 77.59% and 25.41%, respectively. Domestic wastes, septic tank spillages, animal wastes, and nitrate composts are the prime sources of nitrate, while the fluoride-bearing minerals and phosphate fertilizers are the main sources of fluoride in the aquifer regime. Individual non-cancer-causing health index obviously suggested the nitrate as the higher health risk than fluoride. The total non-cancer-causing health index was observed to be more than the acceptable limit of 1.0 in 95.5% of the total groundwater samples concerning infants, children, and adults. The vulnerable intensity of this index appeared to be higher in infants than in children and adults due to the differences in their body weights. The spatial coverage area of very health risk is more in infants (37.45%) than that of children (36.78%) and adults (30.34%). Thus, the present study suggested suitable measures for the improvement of groundwater quality and consequently the health conditions of the locals.

With the recent surge of emerging memory technologies, the demand for storage capacities in various applications is more than ever. Oxide material based memory elements are promising candidates for designing future non-volatile storage architectures. In this work, we investigated the structural, transport and resistive switching (RS) behaviour of a novel hybrid structure made of calcium doped LaMnO3 (LCMO) and reduced graphene oxide (rGO). Very stable and robust bipolar RS behaviour was observed with additional tunability obtained through the variation in the rGO concentration in the structure. The presence of a metal to insulator transition is clearly observed with a lowering of the transition temperature on increase in the rGO content. Both the effects can be attributed to the oxygen vacancy generation and filament formation as confirmed from the X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (HRTEM) measurements. The combined attributes of easy fabrication route, robust switching behaviour and environmental stability of the present system makes it a superior candidate for future non-volatile memory design and oxide electronics.

Future developments in the non-volatile memory design like resistive random access memory (RRAM) holds the backbone of data-controlled applications. The present study reports the investigation of the resistive switching behaviour of a novel nanocomposite system composed of La0.7Ba0.3MnO3 and Graphene (Gr)/reduced graphene oxide (rGO) for memory design. The presence of Gr offers a superior switching behaviour, the microscopic origin of which lies in the formation/breakage of conduction filamentary paths, formed through the presence of oxygen vacancies as supported via X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM) measurements. The change in the resistance states can be accounted for the exchange interaction along the Mn3+–O2−–Mn4+ chain, offering simultaneous control over the resistance states via the electric and magnetic field. The conduction behaviour is dominated by the Fowler-Nordheim tunnelling mechanism. The presence of robust and stable switching behaviour over 1000 cycles, stable ON/OFF ratio, and simple synthesis process indicates the potential of the present material system(s) to be an interesting candidate for future memory design.

The interface magnetoelectric (ME) effect is promising for novel technological applications as it allows the control of interface magnetization at heterointerfaces by the external electric field. Here in this article, we explore the interface ME effect and its sensitivity on interface atomic structure and bonding in ferromagnetic-ferroelectric oxide hetrostructures within the framework of density functional theory. In particular, we consider Fe/AgNbO3 and SrRuO3/AgNbO3 superlattices with different possible defect-free interfaces. Our results suggest that interface magnetization and thereby interface ME effect can critically depend on interface structure. The interface magnetization is found to depend on atomic bondings which are sensitive to atomic displacements at the interface. This leads to ME coupling due to induced change in the interface magnetization as the electric polarization is reversed in the ferroelectric film. In addition, the contribution to interface ME coupling also comes from the change in exchange-splitting between spin-polarized electrons and consequently change in the interface magnetic moments due to ferroelectric polarization reversal. The change in exchange splitting, in turn, is caused by spin-dependent screening of the bound polarization charges at the interface. In Fe/AgNbO3 system, the interface ME coefficient is found to exhibit opposing trend for Fe|AgO and Fe|NbO2 interfaces. In addition to interface ME effect, the formation of ferroelectric interface domain wall (IDW) in these systems is also explored. The IDW is found to form only in SrRuO3/AgNbO3 system with SrO|NbO2 interface due to oppositely oriented strong dipole moments at the two interfaces. The strong dependence of interface ME effect on interface atomic structure may have implication for its experimental observation in oxide heterostructures. In particular, the interface defects may render the conclusive observation of this phenomenon challenging due to resulting fluctuations in the observed data.

Multifunctional materials are of utmost importance owing to the combination of several functionalities into a single device. We present the multifunctional properties, namely, thermoelectric (TE) for energy harvesting and resistive switching (RS) for memory storage in the LaCoO 3 (LCO)–graphene nanocomposite system. The existence of individual phases of LCO and graphene is confirmed from x-ray diffraction and electron microscopy techniques. The x-ray photoelectron spectroscopy measurement reveals the formation of oxygen vacancies in the nanocomposite with the addition of graphene. The bipolar resistive switching behavior observed in a LCO–graphene nanocomposite is explained using space charge limited conduction mechanism and is found to evolve from a trap-limited to a trap-free region with an increase in the graphene volume fraction, which eventually ascribed to the ordering of oxygen vacancies in the nanocomposite system. The endurance plot of the nanocomposite shows a stable RS behavior for consecutive 1000 cycles. On the other hand, the creation of oxygen vacancies in the nanocomposite leads to change in the configurational entropy of charge states of cobalt, which tunes the Seebeck coefficient ( α). The decrease in α leads to an increase in the hopping hole concentration ( n h) estimated using the classical Heikes formula and is consistent with the increase in the electrical conductivity. The increase in oxygen vacancies leads to point-defect scattering, which further reduces the thermal conductivity of the nanocomposite. The optimized TE parameters show a figure-of-merit of 0.004 ± 0.000 48 at 300 K. The simultaneous observation of RS and TE properties in LCO–graphene nanocomposite provides new directions for multifunctional materials.

Surface electronic structure and energetics of (001) surfaces of relaxor ferroelectric Na1/2Bi1/2TiO3 (NBT) are explored theoretically within the framework of ab-initio density functional theory. In particular, polar and nonpolar surfaces of tetragonal NBT with bulk P4mm and P4bm symmetries are explored. For P4mm symmetry, (NaO)-, (BiO)+ and (TiO2)0 terminated surfaces and for P4bm symmetry, (Na1/2Bi1/2O)0 and (TiO2)0 -terminated surfaces are considered. The surface electronic structures for different terminations are found to differ with respect to bulk and with each other due to different polarity compensation mechanisms. In case of (BiO)+ and (NaO)- terminated surfaces, the Fermi level shifts slightly above the conduction band minimum (CBM) and below the valence band minimum (VBM) respectively. The resulting localized surface gap states near the VBM and CBM provides sufficient positive and negative charge required for compensation in agreement with the polarity compensation criteria. Furthermore, localized surface states are also formed at energies (~12 eV) deep in the gap below the VBM. The relative thermodynamic stability, reconstructions and relaxations of NBT surfaces may be expected to be correlated with the formation of these deep energy localized surface states. The magnitudes of surface relaxations are found to depend strongly on the nominal charges of the surfaces. The surface energies of polar NaO, BiO and nonpolar TiO2 terminations are found to be significantly larger than that of nonpolar Na1/2Bi1/2O termination. Thus the arrangement of nonpolar-nonpolar planes forming the sequence –Na1/2Bi1/2O–TiO2–Na1/2Bi1/2O–TiO2- may be expected to be more favourable than the sequence of polar-nonpolar planes -NaO-TiO2-BiO-TiO2-NaO-. This favourable arrangement of nonpolar planes may likely influence the degree of A-site cation ordering in Na1/2Bi1/2TiO3 which in turn may influence the degree of coexistence of R3C and CC phases of NBT at the room temperature.

Nanocomposite made of La0.7Sr0.3MnO3 (LSMO) and reduced graphene oxide (rGO) is a promising candidate for non-volatile memory application in oxide electronics. Here, we report bipolar resistive switching (RS) behaviour in (1-x)LSMO.(x)rGO nanocomposite system, for 0.001 ≤ x ≤ 0.010. The structural characterization revealed the presence of individual constituent phases. The switching behaviour is observed to be very stable over 1000 switching cycles and robust against different voltage sweeping rates with a minimum switching speed of 1.1 μs. An oxygen vacancy induced conduction filament based model is proposed to understand the origin of the switching phenomenon and similar observation is made through high-resolution transmission electron microscopy (HRTEM) measurements.

Theoretical investigations are carried to explore surface electronic structure and surface energetics of (1 × 1) polar and nonpolar (001) surfaces of room temperature tetragonal phase of lead-free relaxor ferroelectric K1/2Bi1/2TiO3 (KBT) within the framework of density functional theory. In particular, polar (KO)-, (BiO)+ and non-polar (TiO2)0 terminations with bulk P4mm symmetry and non-polar (K1/2Bi1/2O)0 and (TiO2)0 terminations with bulk P4bm symmetry are explored. The electronic structures of different terminations differ significantly with respect to bulk and with each other due to surface charge compensation. In case of BiO termination, the Fermi level shifts just above the conduction band minimum (CVM), whereas in case of KO termination, it shifts just below the valence band maximum (VBM) resulting in formation of localized surface states in the band gap with conduction and valence band character. In addition, localized surface states are also formed in the gap at ~11 eV below the VBM. These deep energy localized surface states may be expected to have important implications for surface relaxation and thermodynamic stability of surfaces and their reconstructions. For polar surfaces, surface relaxations are found to be strongly dependent on surface charge and are quite disparate as compared to that for non-polar surfaces. Surface energy of K1/2Bi1/2O termination is found to be much smaller than KO, BiO and TiO2 terminations, suggesting that stacking sequence -K1/2Bi1/2O–TiO2–K1/2Bi1/2O–TiO2- of non-polar planes is significantly favorable energetically than the sequence -KO-TiO2-BiO-TiO2- KO- of polar and non-polar planes in KBT. The preferred stacking sequence of non-polar planes may be expected to have significant influence on the degree of A-site cation ordering in K1/2Bi1/2TiO3.

The prevalence of oral cancer is exponentially increasing and it has become one of the common causes for mortality and morbidity. Oral cancer is a multifactorial disease, but tobacco is regarded as the most important attribute for its development. It can be preventable by the intervention of risk factors. Its early detection can minimize its detrimental eff ects and can improve the quality of life of the patient. The aim of this review article is to identify the current aspects in oral cancer diagnosis and management and to highlight the future prospects in this fi eld.

Introduction Oral carcinoma is a global health problem. India accounts for one-third of world burden with high prevalence rate of 2.5 million and mortality rate of 5.5 lacs per year. Oral carcinogenesis is a multistage process that frequently involves invasion and metastasis that needs early detection and treatment to improve the overall quality of life. The ability of Oral Squamous Cell Carcinoma (OSCC) to metastasize to lymph nodes does not always show a relationship with clinical staging. A spectrum of molecular mechanisms is involved in carcinogenesis, where defect in the regulation of apoptosis is assumed to contribute to the pathogenesis and progression of cancer. Apoptosis regulatory genes include the antiapoptotic protein such as B-cell lymphoma-2 (Bcl-2) gene that might be used as a molecular marker to evaluate the biological behaviour of oral cancer. Aim To evaluate and correlate the Bcl-2 expression in OSCC patients with lymphnode metastasis and without metastasis. Materials and methods The study comprised of 30 samples, 15 cases of metastatic and 15 non-metastatic primary OSCC. All the cases were stained for routine Hematoxylin and Eosin (H&E), and Bcl-2 antibody by immunohistochemistry. The H&E stained sections were evaluated for Lymphocytic Infiltrate (LI) and Pattern Of Invasion (POI). Bcl-2 stained sections were evaluated for staining intensity and distribution. The differences between the groups were statistically analysed using chi-square test. Results The histopathological parameters, LI and POI did not show any statistical difference between the study groups. Expression of Bcl-2 in OSCC was 33.3% among the study groups, where metastatic group showed a positive expression of 13.3% and 20% in non-metastatic OSCC that did not show statistically significance among the study groups. Conclusion There was no significant difference in the expression of Bcl-2 between the study groups. Apoptosis is regulated by interaction among the Bcl-2 gene family. Hence, evaluation of Bcl-2 along with other apoptotic regulating proteins could define the role in pathogenesis and prognosis of metastatic and non-metastatic OSCC.

Introduction: Raman spectroscopy is simple, quick, sensitive and non destructive form of tissue examination that provides vital data about the structure, molecular composition and interactions within a sample. The human hard tissues like teeth and bone are able to resist decay for long even after other tissues are lost, thus have valuable forensic importance. Aim: To ascertain the known age of the teeth by analysing dentin and cementum using Raman microspectrometry and assess the accuracy of age estimation by comparison of dentin with cementum. Materials and Methods: The sound permanent extracted tooth specimens (40) of age ranging between 12-74 years were collected and sectioned longitudinally and different dentinal and cemental areas were analysed by Raman microspectrometry. The spectra of dentin and cementum were used as predictors of age estimation. For each sample, ratios were obtained for dentin and cementum areas, and Pearson’s correlation coefficient was calculated. Ratios, which had a correlation coefficient greater than 0.40 were used for further statistical analysis. This led to selection of ratios only for dentin areas, and it allowed us to develop a regression formula. Partial Least Square (PLS) regression method was used for computing our model. Results: A significant correlation was observed between the actual chronological age and predicted age of the individual using dentinal areas of the tooth. A closest to the estimated result was achieved, with an error of three years between predicted and actual chorological age. Conclusion: Raman microspectrometry may be considered as an alternative to the conventional method of age estimation and contribute to the identification of individuals.

OBJECTIVES: The aim of the study is to compare the Low dose magnesium sulphate regime Vs standard dose with regard to the efficacy, maternal outcome and fetal - neonatal outcome. MATERIALS & METHODS: The study was conducted at Govt. General Hospital Kakinada from June 2009 to September 2010. A Total of 100eclampsia patients were studied with50 cases in each group. In Low dose regime, a loading dose of 4gm Magnesium Sulphate (20ml of 20% solution) given slow IV over 20 minutes. This is compared to standard Pritchard regimen and a maintenance dose of 2gm deep IM 4 th hourly up to 24hrs after delivery/ last convulsion whichever is later. RESULTS: Low dose magnesium sulphate regimen is as effective as Pritchard standard regimen in controlling eclamptic convulsions. No increase in maternal morbidity, mortality and no increase in perinatal morbidity, mortality were noted in the study group. CONCLUSION: A lower dose of magnesium sulphate is suitable and equally effective in Indian women who on an average weigh much less than the western counterparts to control convulsions in eclampsia with no increase in maternal mortality & morbidity (or) perinatal mortality & morbidity with the added benefit of reducing the side effects. The results obtained with this low dose regime bring out the focus for the need to review the correct dose of magnesium sulphate in Eclampsia in Indian scenario.

In recent years Evolutionary computation has its growth to extent. Synthesis of non-uniform linear antenna arrays is one of the most important electromagnetic optimization problems of the current interest. In this paper, the design of non-uniform linear antenna arrays with optimum side lobe level reduction is investigated. Two global evolutionary optimization methods are Particle Swarm Optimization algorithm(PSO) and Differential Evolution algorithm(DE ) are used to determine an optimum set of weights and positions that provide a radiation pattern with optimum side lobe level having uniform progressive phase between the elements. Simulation results show considerable enhancements in array performances using the global optimizers. The paper finally illustrates a comparative evaluation of the two proposed algorithms regarding their applicability as numerical optimization techniques.

Thermopower in cobalt oxides has been a rich area of interest due to the existence of the different charge states along-with different spin states. In this report, we have systematically studied the structural and thermal transport properties of ($1-x$)LaCoO$_3$.($x$)La$_{0.95}$Sr$_{0.05}$CoO$_3$ composite. The Seebeck coefficient ($\alpha$) values for the composite increases at high temperatures compared to the LaCoO$_3$ (LCO) and La$_{0.95}$Sr$_{0.05}$CoO$_3$ (LSCO) systems. The electrical conductivity ($\sigma$) decreases with the increase in the LSCO fraction which may be attributed to the localization of charge carriers due to intersite diffusion. All the samples show increase in the value of $\sigma$ with increase in temperature. The thermal conductivity ($\kappa$) values decrease with the increase of LSCO content in the composite and the phonon thermal conductivity dominates over the total thermal conductivity. We observe a maximum value of figure of merit (ZT)$\sim$0.06 at 640\,K for $x=$0.05.

Aim The aim of the present study was to evaluate, compare, and correlate the types of collagen fibers seen in different grades of oral cancer. Methods Thirty cases of histologically-diagnosed, well-, moderately-, and poorly-differentiated oral squamous cell carcinoma (OSCC) were retrieved from the archives of the Institute. Collagen was evaluated using picrosirius red stain and immunohistochemical analysis of the antibody to type III collagen. A correlation between these findings and the grade of OSCC was evaluated. Results Collagen fibers showed a change in birefringence ranging from reddish–orange to greenish–yellow in well- to poorly-differentiated oral squamous cell carcinoma. The findings were statistically significant for polarizing colors observed in grades of OSCC (P

A reverse phase high performance liquid chromatography (RP-HPLC) method for the simultaneous estimation of Sitagliptin phosphate and Metformin hydrochloride in marketed tablet formulations is developed. The determination was carried out on an XTerraC8 (4.6 × 100 mm, 3 µm) column using a mobile phase of pH-9 phosphate buffer solution: acetonitrile: methanol in the ratio of 35:45:20. The flow rate was 0.6 ml/min. The analyte was monitored using UV detector at 260 nm. The retention time for Sitagliptin phosphate was 3.056 mins and for Metformin hydrochloride 2.420 mins. Linearity of Sitagliptin and Metformin were found in the range of 50 ppm to 150 ppm. Percentage recoveries were obtained in the range of for Sitagliptin 99.5% and for Metformin 100.4%. The proposed method is precise, accurate, selective, robust, reproducible and rapid for the simultaneous estimation of Sitagliptin phosphate and Metformin hydrochloride in tablet dosage forms.

INTRODUCTION: VWD is named after Erik Adolf Von Willebrand, a Finnish pediatrician who first described the disease in 1926. Von Willebrand disease is the most common hereditary coagulation abnormality described in humans, although it can also be acquired as a result of other medical conditions. It arises from a qualitative or quantitative deficiency of Von Willebrand factor (VWF), a multimeric protein that is required for platelet adhesion. There are three forms of VWD: VWD Type-I, Type-II, Type-III. Within the three inherited types of VWD there are various sub-types.1 VWD Type-1 is the most common type of the disorder2 and those that have it are typically asymptomatic or may experience mild symptoms such as nose bleeds although it may be severe in some cases. There are various factors that affect the presentation and severity of symptoms of VWD such as blood type.3

First-principles density functional calculations are performed to investigate the lattice dynamics, Infrared reflectivity, and Raman intensity spectra of a lead-free ferroelectric K1/2Bi1/2TiO3 system. In particular, the A-site cation ordering in K1/2Bi1/2TiO3 and its effects on lattice dynamics and the Raman spectrum are explored. The results suggest that the cation ordering at the A-site in K1/2Bi1/2TiO3 significantly influences its Raman spectra. From the analysis of theoretical and experimental Raman spectra, it is suggested that randomly arranged cation ordered nanoregions with different A-site orderings are formed in K1/2Bi1/2TiO3 samples. The random arrangement is favored by entropy contributions to free energy and may explain the lack of observed long-range A-site cation ordering in K1/2Bi1/2TiO3. Further, it is suggested that partial A-site cation ordering may also occur in K1/2Bi1/2TiO3 favored by kinetic factors during sample preparation. The Born effective charges of K and Bi ions at the A-site are computed and found to be significantly disparate, thereby suggesting hetero-polar activity at the A-site in K1/2Bi1/2TiO3. The formation of A-site hetero-polar cation ordered nanoregions and their random or/and partially ordered arrangement in K1/2Bi1/2TiO3 may play an important role in the determination of its relaxor properties apart from the dominant role played by polar nanoregions. The computed Infrared reflectivity and Raman intensity spectra are expected to provide benchmark first-principles results for further analysis of experimental spectra and results.

Lead free polycrystalline K1/2Bi1/2TiO3 (KBT) was prepared by solid state reaction method. Experimentally observed frequencies of Raman modes signified its tetragonal phase and matched reasonably well with theoretically calculated values. The relaxor nature of this material was observed in the temperature dependent real part of permittivity and dielectric loss curve. The value of the degree of diffusiveness was estimated from the modified Curie-Weiss law, which is 1.99, confirmed its relaxor behavior. The validation of this behavior was justified by the Vogel-Fulcher relation. The shoulder in the imaginary part of the modulus (M") and permittivity (Ԑ") spectra revealed the presence of polar nano regions (PNRs). The evidence of PNRs was detectable above freezing temperature which became weaker when the temperature exceeded Tm (temperature at the maximum of dielectric constant). Electric field induced polarization and strain curve showed the stabilization of long range ferroelectric order of the specimen at room temperature. Moreover, we obtained the discharge energy density and strain of 0.46 J/cm3 and 0.12%, respectively, at the maximum application of the electric field of 115 kV/cm at room temperature.

The study was conducted in 2000 adult Punjabi females ranging in age from 20 to 60 years during the period 1998-2001. The methodology comprised of interview and clinical examination. Blood pressure...

Corals are invertebrate animals belonging to the phylum Coelenterata distributed across the tropical marine environment living at a depth ranging from the low-tide mark to 6000 m depth. It extents to approximately 1.2% of the continental shelf area and 0.09% of the total area of the world’s ocean. Majority of the world’s coral reefs occur in the Indo-Pacific region centred around the Coral Triangle. It provides habitat for large variety of marine fauna and livelihood to millions of people. However, this vital ecosystem is under increasing threat from both anthropogenic activity and climate change. Measures such as declaring marine protected areas (MPAs), ban on international trade of vulnerable species, legislative measures controlling fishing and exploitation of coral fauna, control of damaging activity in the coastal areas, providing alternate livelihood to the locals and creating awareness among the all the stakeholders are discussed in this chapter.