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Polycrystalline Zn Zr substituted barium hexaferrite (BaFe12-xZnx/2Zrx/2O19 where x = 0.3, 0.5, 0.7 and 1.0) specimen have been synthesized by two different methods, namely conventional and microwave sintering. The latter has resulted in magnetoplumbite phase in 5 min at a lower temperature (1000 °C). The values of magnetic parameters of different samples are extracted from the corresponding M − H loops using law of approach to saturation magnetization. A high value of saturation magnetization (Ms = 76 emu/g) is obtained for a conventionally sintered sample. Still higher value of saturation magnetization (Ms = 104 emu/g) has been obtained for the microwave sintered cation substituted sample. The increase in the magnetization has been attributed to the magnetic reordering of iron cations in the non-magnetic Zn2+-Zr4+ substituted samples. The coercivity of the microwave processed substituted samples has been drastically reduced to 163 Oe (from 2961 Oe for conventionally sintered pristine sample). The observed decrement can be ascribed to the increase in particle size and reduction in magnetocrystalline anisotropy (2.58 × 106 erg/cc). Raman spectra of the substituted samples have shown a shift in the vibrational frequencies (characteristic of magnetoplumbite phase) with cation substitution. This suggests that the non-magnetic Zn Zr cations replace Fe3+ from certain interstitial sites (4f1, 4f2, 2b and 12k).

Nanocrystalline Ni1-xCoxFe2O4 (x = 0.0, 0.4, 0.5, 0.6, 1.0) samples were synthesized using sol-gel technique. X-ray diffraction (XRD) and vibrational spectroscopy techniques were employed to study the structure, cation distribution and ordering in the Co2+ substituted nickel ferrite (NCFO) samples. The XRD analysis of the specimen confirmed the formation of single cubic spinel phase. The substitution of Co2+ for Ni2+ cations resulted in the increase in lattice parameter. The distribution of cations in tetrahedral (A) and octahedral (B) sites in the unit cell was estimated using X-ray diffraction and Raman data. Infrared and Raman spectroscopies too confirmed the spinel phase formation in the samples. An observed systematic shift and asymmetric broadening in Raman spectra with a change in Co2+ concentration were correlated with different ligand parameters such as effective mass, bond length and force constant, etc. A Raman peak (A1g) was employed to estimate the Co2+/Ni2+ and Fe3+ distribution between the two interstitial sites. The estimation of cation distribution made by the two techniques (Rietveld refinement of X-ray diffraction data and Raman spectroscopy) is in very good agreement. It is revealed that nickel ferrite (NFO) is nearly inverse (96% Ni2+ on B-sites). The substitution of Co2+ in NFO results into a partially inverse mixed ferrite phase with Co occupying nearly 18% A-sites in Ni0.5Co0.5Fe2O4 and 25% in CoFe2O4.

Tin oxide films with thicknesses in the range from 5 to 110 nm have been deposited by reactive dc magnetron sputtering of Sn in Ar + O plasma at a low working pressure of 1.0× 10 −3 Torr on glass substrates at different temperatures (150–400 °C). The effect of deposition time, substrate temperature, and oxygen partial pressure on surface morphology , crystallographic structure, optical properties, and photoluminescence characteristics of SnO 2 films has been studied and correlated with their defect structure . The structural transformation from nanocrystalline to polycrystalline of thicker films >40 nm and films were grown at higher temperature is explained based on adatom mobility and uniform substrate coverage. Based on photoluminescence characteristics and transmittance spectra, the 20 nm thick film exhibits the least defect structure and best electronic and optical behaviors.

Polycrystalline samples of Ni1 − xCoxFe2O4 (where x = 0.0, 0.4, 0.5, 0.6, 1.0) have been synthesized by solid state sintering of stoichiometric nanoparticles prepared by sol–gel technique. Rietveld refined powder X-ray diffraction patterns confirm the formation of a single cubic spinel phase in each sample. Substitution of cobalt ions results in the increase of the lattice parameter. The saturation magnetization and coercivity of all the samples were measured using PPMS-VSM and found to increase from 51.6 to 82.2 emu/g, and 9.7 to 588 Oe, respectively. The observed magnetic ordering is explained on the bases of two sublattice model and redistribution of cations in these partially inverse Co substituted Ni ferrite samples. The strong increment (60 times) in the coercivity is explained on the bases of microstructure and magnetocrystalline anisotropy. Cation redistribution in these samples is proposed on the basis of the observed magnetic moment. Close matching of lattice parameter calculated from the magnetic data and estimated from the X-ray diffraction data supports the proposed cation redistribution in the partially inverse spinel phase of NCFO.

In this paper we report the structural, vibration, and electronic-structure parameters (bonding and valence of cations) of single phase cubic mixed spinel nanoparticles of (ZnδMnγFe1−(γ+δ))[NixZn0.5−δMn0.5−γ−xFe1+(γ+δ)]O4 where x = 0.05–0.45 with an aim to determine cation-distribution i.e. δ and γ in these samples. The Raman spectroscopy has established that only Fe and Zn cations occupy tetrahedral interstitial sites in a FCC anion lattice in nearly equal fraction, and Mossbauer spectra have shown that Fe3+ cations are present at both, tetrahedral and octahedral interstitial sites and Ni2+ cations are situated at the octahedral sites in all the substituted samples. The photoelectron spectra also revealed the presence of Fe3+ cations at both the interstitial sites. The best possible cationic distribution in Ni substituted Mn–Zn ferrites has been estimated by reiteratively calculating the intensity ratios of various pairs of X-ray diffraction peaks and matching with the observed intensity ratios.

Background: Psychiatric morbidity in psoriasis is influenced by socio-cultural factors. Most of the studies in this perspective are done in western setup; to extrapolate them on Indian patients with different demographic and socio-cultural profile may not be appropriate. Our study was designed to evaluate the prevalence and its correlation to various socio-economic variables in Indian patients. Methods: This was a non-interventional, cross-sectional study, in which 125 consecutive psoriasis patients over one year were screened for psychiatric morbidity. Demographic and disease parameters including Psoriasis Area and Severity Index (PASI), Psoriasis Disability Index (PDI), General Health Questionnaire (GHQ), Comprehensive Psychopathological Rating Scale (CPRS) were recorded along with the severity assessment of psychiatric morbidity and its relation to these variables was analyzed. Results: Among 125 psoriasis patients, 43 (35.2%) had psychiatric morbidity. Thirty two (26.4%) had depression, 3 (2.4%) had dysthymia, generalized anxiety disorder and adjustment disorder each, and 2 (1.6%) suffered social phobia. A significant increase in psychiatric morbidity was seen with increase in PDI and PASI scores. Conclusions: There is a significant psychiatric morbidity associated with psoriasis and it increases with severity of the disease.

Background: Body art in the form of ornamental tattoos has been prevalent since ages and is followed with increased popularity in modern times. Tattoo prevalence ranges from 8.5% to 24%, higher among younger ages. Two third of such people who ever had a tattoo reported of being regretted of having a tattoo itself while 2% have adverse reactions. The aim was to study the adverse reaction to tattoos and histological variants in the chronic tattoos. Methods: An observational prospective study was conducted on patients presented with adverse reactions to tattoos in the out-patient department of dermatology, venereology and leprosy, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India from July 2012 to June 2013. Relevant clinical profile of the patient was studied and histopathological examination with a 5 mm punch biopsy was done in chronic cases. Results: A total of thirty-three cases (19 male and 14 females) with complications to tattoos were registered over the period of one year. Thirty patients had their tattoo from an amateur while only three had from a professional tattooist. Twenty one (63.6%) had acute complications and twelve (36.3%) had chronic complications. Histpathological examination (HPE) was done in ten of these cases and two refused biopsy. The findings were suggestive of lupus vulgaris (LV) and foreign body granuloma (FBG) in three each; chronic granulomatous changes in two, and spongiotic dermatitis (SD), and lichen planus hypertrophicus (LPH) in one case each. Conclusions: Tattooing being largely unregulated has led to variability in contents of tattoo solution and inadequate sterilization during the procedure. This combined with lack of awareness, increases the chances of various adverse reactions. So it is extremely important to strictly regularize the tattoo practice and to increase awareness about tattoo complications among consumers, tattoo artists and dermatologists.

A study of electron- and magneto-transport behavior of ultrathin SnO 2 films of thickness ≤40 nm with high conductivity of 537 Ω −1 cm −1 deposited on glass substrate by using DC reactive sputtering has been carried out at low temperature. Hall effect measurements revealed these SnO 2 films to be degenerate down to 40 K. The films with thickness >5 nm are found to undergo a metal-semiconductor transition below 140 K, and show a negative MR of ∼1.5% at a magnetic field of 0.9 T below 40 K. Both these phenomena have been ascribed to the presence of weak localization of electrons at low temperature. Electron transport behavior has been explained using quantum correction to conductivity. Estimated inelastic scattering lengths were found to be longer than the film thickness which supports two-dimensional nature of electron- and magneto-transport in these ultrathin films.

During the last few decades, democracy, as the most preferred form of government, has been repeatedly revisited. Considerable literature has grown up round the concepts of inclusive governance and social responsibility as essential elements of democracy. Besides the learned scholars, some international organizations such as the World Bank, the World Health Organization and the United Nations Development Programme have become involved in this discussion. In the so-called developing world of South Asia and Africa, the fruits of freedom, rule of law and economic growth have been cornered by the few and not shared by all. The worst sufferers have been the most deprived and marginalized sections: women, tribals, people with disabilities, ethnic, religious or other minorities, the aged, social outcasts and the poor and least developed. For the debate on inclusive government and socially accountable democracy to be meaningful to ordinary citizens, the first categorical imperative is to shear it of much of its jargon. Democracy today is believed to be a system under which the people govern themselves, through the representatives they elect, under a system they choose. Yet representative democracy must graduate to participatory democracy, where the people are conscious of their rights and obligations, assume responsibilities and partake in decision-making processes. Furthermore, democracy has to be inclusive of the interests of all, equally and without discrimination. Special attention has to be paid to the disadvantaged and deprived. Good governance has to be democratic, citizen-friendly, clean and free of corruption. All the state functionaries, at all times, must be answerable and accountable to the ultimate masters in democracy: the people. Inclusive governance requires decentralization of power, equal participation of the people, equality of all before law and real empowerment of the people, with a bottom-up approach.

In the present paper an attempt has been made to understand the growth mechanism of SiGe alloy nanowires synthesized in H-mode cylindrical microwave cavity resonator at 900 °C in a short time of nearly 5 min. The role of ambience, microwave H-field, duration of interaction with microwaves and germanium concentration in the starting precursor have been investigated. It is believed that H-field of microwaves efficiently interacts with the starting precursor powder in air ambience and results in superheating/supersaturation, which gives rise to the formation of innumerable critical sized nuclei via heterogeneous nucleation, leading to one dimensional growth of cylindrical nanowires.

Functionally graded tungsten–copper bimetallic compact with fine microstructure and good mechanical property has been synthesized by employing microwave heating method at a temperature of 800 °C and in a short processing time of 30 min. Scanning electron microscopy and energy dispersive X-ray analysis revealed the graded structure of synthesized sample. The fine microstructure of tungsten in each layer is caused by arrested grain growth because of the short sintering time. The overall relative density of the W/Cu functionally graded sample has reached 87% of the theoretical density. Vickers microhardness measurements, across the length of a compact, show increase in hardness value of the sample with the increase in tungsten content. The experimental hardness values match well with the theoretically calculated hardness values.

Single-phase nanoparticles of Mn0.5Zn0.5Fe2 O 4 (MZF) with improved magnetic properties were prepared from the precursor (formed by chemical route) by microwave processing technique at 500 ∘C in only 3 min. Crystallographically, these were found to be of spinel phase. Using Debye-Scherrer formula, the particle size of conventionally sintered powder is estimated to be about 20 nm, whereas that of microwave processed is nearly 50 nm with improved grain size. The field emission scanning electron (FESEM) and transmission electron (TEM) micrographs revealed the particles in microwave-processed samples to be spherical in shape and confirmed the sample size (to be nearly 50 nm). Room temperature magnetization measurement of conventionally sintered samples (by vibrating sample magnetometer (VSM)) showed their superparamagnetic nature with saturation magnetization of nearly 19 emu/g. The microwave-processed samples showed improved saturation magnetization of nearly 36 emu/g, which is even better than the reported value.

Measurement of electrical and magnetic parameters of thin/thick films at microwave frequencies has always been challenging. This is because the measurement of permittivity and permeability of the films in GHz range is not as straight forward as of the bulk samples. The present paper reviews some of the available techniques with emphasis on the efforts carried out in authors’ laboratory in this direction during past 10–15 years.

The basal cell carcinoma is the most common skin tumour especially affecting the white individuals worldwide. The exact incidence of basal cell carcinoma is not known from India but non melanoma skin cancers comprises about 1-2% of cutaneous tumour in India. The most common skin tumour is squamous cell carcinoma in albinism and the incidence of basal cell carcinoma is less. Hereby, we report a peculiar case of basal cell carcinoma in albinism to highlights the importance of early recognition and diagnosis of suspected lesions by performing histopathological examination in unusual circumstances.

The effect of substitution of Mg–Zr for Fe in M-type barium hexaferrite (BHF) and of processing technique on the magnetic properties and microstructure has been reported in the present paper. Significant changes in magnetic properties have been observed on substituting Fe ions by Mg and Zr ions in M-type barium hexaferrite, i.e. BaFe 12 O 19 as well as by single mode microwave processing. The single mode microwave processing of the undoped sample reduced the coercivity to nearly 25% of the value for the sintered sample along with the enhancement in magnetization, thereby making it suitable for memory devices. The improvement in magnetic properties is explained on the basis of microstructure. The addition of substituents, though assisted in the formation of single phase, it, however, degraded the magnetization besides decreasing the coercivity, possibly due to substitution at the octahedral sites.

Microwave Processing and Characterization of Ferrites and Semiconductors ??

Genetic Variability, Character Association and Path Analysis Studies for Grain Yield and Contributing Traits in Rice (Oryza Sativa L.) under Temperate Conditions of Kashmir A comprehensive study was done for the assessment of genetic variability, character association and path-coefficient using fourteen agro-morphological traits among 35 rice (Oryza sativa L.) genotypes under temperate conditions of Kashmir valley. Analysis of variance (ANOVA) revealed a substantial level of variability among the tested genotypes for all the traits. The greater values of phenotypic coefficient of variation (PCV) over genotypic coefficient of variation (GCV) for all the characters unveiled the influence of environment on character expression. Harvest index showed the highest values of GCV (33.26) and PCV (33.59) and lowest for 1000 grain weight (6.66) and (7.08). High heritability together with high genetic advance was observed in biological yield (0.99) and (53.01). Number of spikelets per panicle (0.49). (46.50), denotes the number of filled grains per panicle (0.99) and (41.90). However, high heritability associated with low genetic advance as percentage of mean was observed for days to maturity (97.00) and (15.11) and 1000 seed weight (89.00) and (12.90). Correlation studies revealed that harvest index (0.47) and (0.43) showed significant positive correlation with grain yield per hill at both genotypic and phenotypic level. While as days to 50% flowering (-0.31) and (-0.28) showed significant negative correlation with grain yield per hill. Path coefficient studies revealed that at genotypic level flag leaf length (0.62) showed high direct positive effect with grain yield per hill followed by flag leaf width (0.61) - while as at phenotypic level flag leaf area (0.49) showed maximum positive direct effect with grain yield per hill followed by harvest index (0.36).)....