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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).

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.

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.

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 present paper deals with the study of photoluminescence (PL) and the other physical properties (structural, electrical and optical) of SnO2 thin films with controlled disorder and intrinsic defects induced during the reactive magnetron sputtering by changing oxygen flow rate from 12 to 16 sccm. The changes in unit cell volume, near band-edge optical transparency and width of Urbach tail in the films are correlated with the structural disorder and presence of intrinsic defects induced by growth under different oxygen partial pressures. The increased intensity of the PL near UV emission and decrease in the intensity of visible emission peaks with increase in oxygen flow rate is linked with the decrease in oxygen vacancies and tin interstitials in the films. With increasing oxygen content, whereas the electrical resistivity of the films minimizes to a value of 4.3 × 10−2 ohm cm at 14 sccm, the mobility of the films increases to a saturation value 15 cm2 V−1 s−1. The donor-defect concentration linked carrier density is observed to decrease monotonically from 2 × 1019 to 0.6 × 1019 cm−3.

Silicon germanium alloy has successfully been synthesized in a 2.45 GHz, single mode microwave H field at 900 °C in 5 min in the Microwave Laboratory. The phase formation occurs at a temperature which is lower by 400 °C than its equilibrium temperature. In the present paper an attempt has been made to understand the mechanism of rapid alloying of Si and Ge at a much lower temperature in microwave H field. The shape and size of starting particles play a significant role in microwave absorption. It is proposed that the interaction of H field at 2.45 GHz first induces B-field in the irregular shaped precursor powder particles of different sizes; the gradient in induced magnetic flux generates circulating electric field. Consequently, dipolar losses are induced by local electric field in the pellet, which generate heat and culminate into rapid alloying of Si and Ge (nonferric diamagnetic elements). Furthermore, magnetic reorientation of diamagnetic fine particles by H-field at 2.45 GHz assists in an efficient heating of the Si and Ge powders and results in alloy formation at a much lower temperature.

The present study was carried out in Kashmir (India) to assess the genetic variability for grain yield and component traits among 14 red rice ecotypes from temperate region (locally known as Zag for its coloured kernels) and correlation and path coefficients were also studied for fifteen agro-morphological characters. Genotypic and phenotypic coefficients of variation were high for grain yield, secondary branches per panicle and panicle weight; moderate for grain number per panicle, grain length:breadth (L:B) ratio and panicle density. High heritability accompanied by high to moderate genetic advance for panicle density, days to 50% flowering, plant height, grain number indicated the predominance of additive gene action for the expression of these characters. Grain yield was found to be positively and significantly correlated with number of tiller per plant, panicle density m-2 and number of grain per panicle at both genotypic and phenotypic levels indicating the importance of these characters for yield improvement in this material. The results of genotypic path analysis revealed that panicle density had the highest positive direct effect followed by plant height and days to flower. The overall results indicated that selection favouring higher panicle density, test weight and panicle weight and medium plant height with a reasonable balance for moderate grain number would help to achieve higher grain yield in this population of red rice ecotypes.

This paper presents our results on the significant effect of application of electric field during deposition on various properties of thin SnO2 films, especially in the ultrathin regime. SnO2 films of 25-75 nm deposited on glass substrates without and with the presence of electric field (32 V/cm) during deposition were compared. It is found that the presence of field has improved the crystallinity and stoichiometry of the film along with its transmittance. Significantly high mobility of 43 cm2/V.s at low thickness of 25 nm resulted in a reasonably low resistivity of 1.5 ohm-cm as a consequence of the field assisted growth.

In the present paper, DC magnetization investigation on the insulating nanocrystalline powder samples of Ti 1− x Mn x O 2 ( x = 0, 0.05, 0.10, and 0.15) prepared by simple chemical route is reported. Structural measurements revealed phase pure anatase structure of TiO 2 when x ≤ 0.05 and a mixture of anatase and rutile TiO 2 along with the signature of Mn 3 O 4 phase for x > 0.05. Magnetic measurements exhibited the presence of ferromagnetic ordering at room temperature in samples having either small fraction of Mn or no Mn at all. This ferromagnetic signature is accompanied with paramagnetic contribution which is found to dominate with increase in Mn concentration. The Ti 1− x Mn x O 2 sample having highest Mn concentration of x = 0.15 showed nearly paramagnetic behavior. However, at low temperatures, additional ferrimagnetic ordering arising due to Mn 3 O 4 ( T C = 42 K) is evidenced in the doped samples. Consistent with the XRD investigations, the isofield DC-magnetization measurements under field cooled and zero field cooled (FC–ZFC) histories corroborated the presence of Mn 3 O 4 phase. Also, distinct thermomagnetic irreversibility has been observed above 42 K. These results are suggestive of presence of weak ferromagnetic ordering possibly due to defects related with oxygen vacancies.

A simple theoretical model is developed for studying the magnetic behavior of films at microwave frequencies, and verified experimentally on the ferrite-polymer thick-film samples. The measured values of permeability by the proposed model/technique are found to be in good agreement with the values obtained by the standard cavity perturbation technique.

Microwave Processing and Characterization of Ferrites and Semiconductors ??

We measured dielectric, magnetic, and microwave properties of Co 2U hexaferrite (Ba4Co2Fe36O 60) polycrystalline bulk and composite thick film samples, and studied the effect of annealing temperature on phase formation and microstructure. We synthesized the bulk samples from a precursor prepared by the citrate method. The values of dielectric constant at radio frequencies (50 Hz-1 MHz) of the bulk Co2U12 sample sintered at 1200degC are much higher, and the resistivities are lower, compared to M-type barium hexaferrites. Coercivity is also low, having a value of 5 G for the Co2U12 sample, whereas the saturation magnetization value is 59 emu/g, which is comparable to that of M-type hexaferrites. We also measured the complex permittivity and permeability for Co2U12 samples at microwave frequencies and found the values high compared to M-type barium hexaferrite at these frequencies. Thick composite films were prepared from a ferrite-polymer mix, and all the above properties were studied for these films. We observed that these thick films have lower values of dielectric and magnetic parameters both at low and microwave frequencies. We measured microwave-absorbing properties for the ferrite-polymer sample (ferrite to polymer ratio 70/30) which showed a maximum reflection loss of -37.5 dB at 11.5 GHz for the 3.5-mm-thick sample

Alloy thin films of ternary system Co – Ni – Fe and binary systems Co – Fe , Co – Ni and Ni – Fe consisting of ~50 nm grains have been deposited by a simple and industrially viable technique of electrodeposition in galvanostatic mode on ITO-coated glass. Bath composition and current density have been varied to prepare films of different compositions and thus, in turn, obtain suitable composition for better magnetic properties. Further, an attempt has been made to deposit films in the presence of Mg 2+ in the bath and to study its linkage with the magnetic properties, i.e., saturation magnetic flux density, BS, and coercivity, HC. Our results clearly demonstrate that addition of Mg 2+ ions in the bath helps in increasing the BS considerably.

Co/Cu multilayers were electrodeposited in potentiostatic mode, using two different sulphate baths, one without any additive and other containing trisodium citrate. Deposition parameters, like deposition potential and deposition time, were established for both the baths by carrying out a series of cyclic voltammetry and chronoamperometric experiments. Thin films, having 2–20 bilayers, were electrodeposited under the established parameters. It was observed that films deposited from bath containing trisodium citrate were comparatively much smoother than films deposited from additive free bath. The films with 20 bilayers, deposited from additive free bath, exhibited a room temperature magnetoresistance of 1.5% at 9 kG, whereas magnetoresistance value enhanced to up to 5.6% at 9 kG for films deposited from trisodium citrate bath for same number of bilayers.

Superconducting bulk MgB2 samples have been synthesized by employing sintering technique without using any additional process steps, generally undertaken in view of the substantial loss of magnesium, during heat treatment. Starting with Mg rich powders having different atomic ratios of Mg : B, as against the nominally required Mg : B = 1:2 ratio, we have obtained superconducting MgB2 samples of different characteristics. The effect of excess Mg in the starting mixture and processing temperature on the phase-formation, transition temperature (T C) and critical current density (J C) have been investigated by electrical transport and a.c. susceptibility measurements. The X-ray diffraction and X-ray photoelectron spectroscopic analyses of MgB2 bulk samples have been carried out to understand the role of excess Mg and the effect of processing temperature. It is established that MgB2 samples with high critical current density can be synthesized from a Mg rich powder having Mg : B in 2:2 ratio, at temperatures around 790°C. Critical current density has been found to vary systematically with processing temperature.

Polycrystalline cobalt-substituted lithium ferrites with general formula Li0.5−x/2CoxFe2.5−x/2O4 (x = 0.0, 0.2, 0.4 and 0.5) were prepared by a non-conventional citrate precursor method, which is advantageous over conventional (solid state sintering) method because of low temperature (600 ° C) processing. Small amounts of Bi2O3 (0.5 wt.%) were added to reduce the porosity and dielectric loss tangent at sintering temperatures (1000–1200 °C). The complex magnetic permeability (μ′ − jμ″) and complex dielectric permittivity (ϵ′ − jϵ″) of cobalt-substituted lithium ferrites were measured in the 8–13 GHz microwave frequency range. The systematic variations of the real and imaginary parts of both permeability and permittivity with frequency and composition have been analyzed. The minimum value of ϵ′ ∼ 11.3 measured for x = 0.4 substituted lithium ferrite is observed for a sample sintered at 1000 °C. The highest values of ϵ′ and ϵ″ were observed for samples sintered at 1200 °C. μ′ varies between 1.84 and 3.90 for pure and cobalt-substituted lithium ferrite bulk ceramics. The spinel structure of the samples was confirmed by X-ray diffraction (XRD).

Ferromagnetic nanomaterials are of particular interest, because at nanoscale a crystallite can exhibit a single magnetic domain. These nanomaterials therefore exhibit different magnetic properties as compared to bulk. Recently, barium ferrite has gained importance due to its potential use in magnetic recording and in microwave devices. Barium ferrite nanoparticles are prepared by the citrate precursor method by varying the pH of the solution and calcination temperature. The effect of particle size and capping reagent on the structural, dielectric and magnetic properties of the resulting barium hexaferrite particles has been studied, and reported in the present paper.

Cu–Co granular films have been prepared by galvanostatic dc electrodeposition in a single sulphate bath. The magnetoresistance ratio (MR={( R H − R 0 )/ R 0 }×100) increased with increase in annealing temperature until 450°C, beyond which MR starts decreasing. Lower coercivity values along with non-saturating behaviour of the room temperature magnetization curves indicated the presence of an appreciable amount of superparamagnetic clusters. The average cluster size was calculated by fitting the superparamagnetic component of magnetization to Langevin equation. The average radius of the Co clusters (assuming spherical shape) was calculated to be 1.87 nm for an as-deposited film and 1.57 nm for a film annealed at 400°C for 1 h. The lowering of average cluster size with increase in annealing temperature in the metastable films is attributed to the segregation of many new (smaller) Co clusters.

We have been able to prepare ultrafine powders of pure and doped La 0.67 Ca 0.33 MnO 3 (LCMO) at a relatively lower temperature of 550°C using a simple, cost effective and versatile PVA-based chemical route. A maximum magnetoresistance (MR) ratio of −25% is obtained at 20 K in a magnetic field of 3 kOe. Magnetoresistive behaviour being retained in the nanopowders may have implications for enhancing data storage capacity. The semicondutor-to-metal transition temperature, T p , however, shifts towards the lower temperature as the particle size is reduced. To improve T p and near-room-temperature MR additives like NH 4 NO 3 and citric acid have been used. In addition, Pb is substituted for Ca.

In the present work, Si0.95Ge0.05 alloy nanowires were synthesised in a single-mode resonant cavity operated in H 011 mode in ambient at 2.45 GHz in a short duration (5 min) and at a temperature (900 ◦ C) lower than the equilibrium alloy-phase formation temperature. The photoluminescence (PL) studies were carried out at room temperature. The intense PL peaks, in the energy range of 2.9–3.6 eV, can be ascribed to radiative recombination of the generated carriers. The low temperature (100–250 K) dc electrical-transport is investigated; and the activation energy is estimated to be lower by an order than that of polycrystalline samples. The lower activation energy is possibly due to electronic/structural defects introduced by the non-equilibrium growth process and high aspect ratio of the grown nanostructure. With these improved characteristics, the alloy nanowires can be exploited for device fabrication.

In the present paper, a modified self-flux technique has been successfully employed for the growth of pure and praseodymium substituted (partially) large single crystals of high temperature superconducting Y1−x Pr x Ba2Cu3O7−δ (x = 0·0,0·2,0·4). Typical sizes of the platy and bulky crystals of pure YBCO(123) material are ≈ 2 × 2 × 0·1 mm3 and 4 × 1 × 1 mm3, respectively. In case of Pr-substitution, the typical sizes of platy and bulky crystals of Y0·8Pr0·2Ba2Cu3O7−δ and Y0·6Pr0·4Ba2Cu3O7−δ materials are ≈ 2 × 3 × 0·1 mm3 and 5 × 1 × 1 mm3 and ≈ 1 × 1·5 × 0·1 mm3 and 7 × 0·2 × 0·1 mm3, respectively. The morphology and growth habit of the as-grown single crystals and the critical transition temperature (T c) of the oxygenated crystals were found to depend on the Pr-content.

Bismuth germanium oxide (BGO) has tremendous application potential due to its favourable electro-mechanical and electro-optic properties. The present paper describes some of our preliminary results on the variation of dielectric constant with applied high hydrostatic pressure and temperature. It is noted that BGO is a promising candidate for its application as a pressure sensor.

DC magnetization measurements have been carried out on bulk YBCO/Ag composites with silver content up to 20wt per cent. DC fields in the range 0·5 mT to 200 mT have been used to investigate the inter- and intragranular properties at 77K. The AC susceptibility as a function of temperature at different AC fields (0·026–0·30 mT) has also been studied. Under small DC fields (≈ 4 mT), depending on the Ag content andH max, the M-H loop shows a complicated behaviour. This behaviour can be explained on the basis of effect of strong field dependence of transport critical current, grain size and intragrain critical current densityJ cgm on low-field M-H loop. The estimation of intergranular critical current densityJ cjm from these loops does not remain a simple function of ΔM/d. The AC susceptibility measurements show a small increase inJ c(T) with silver content under low AC fields only, consistent with the transportJ c data; beyond thatJ c(T) decreases. This improvement inJ c(T) and transportJ c with silver can be ascribed to the improved coupling between grains but not to the pinning. Also at higher field (H max>20 mT) the addition of Ag decreases the intragrain critical current density. The upper critical field of intergranular regionH c2j and lower critical field of intragrain regionH c1g also decrease with silver content.

The role of cationic ratios (Sr/Ca and Bi/Pb) in the evolution of high-T c phase (2223) in samples prepared under different sintering conditions, starting with a composition of Bi2Pb0.6Sr2Ca2Cu3.1Oy, has been investigated by employing energy-dispersive X-ray analysis, scanning electron microscopy and X-ray diffraction. As manifested by the observed decrease in Sr/Ca ratio, an increase in sintering temperature from 822 to 852 °C increases the disorder in Sr-O and Ca layers. The observed increase in the volume fraction of 2223 phase and the contraction inc-axis parameter have been explained on the basis of the observed decrease in Sr/Ca ratio. It thus appears that the disorder caused by the intersubstitution of Ca and Sr in SrO and Ca layers and partial replacement of Bi by Pb in the structure promote the evolution and growth of 2223 phase.

The role of preparation conditions and the effect of addition of Pb in Bi-Sr-Ca-Cu-O (BSCCO) superconductor, on theTc,Jc and grain orientation have been studied. Calcination at a temperature higher than the melting point of Bi2O3 after the prereaction at 800°C leads to formation ofc-axis oriented nearly single phase material. The presence of lead yields a nearly highTc phase (2223) exhibiting a maximum transition temperatureTc=110 K and ΔTc=2 K. The addition of lead and grain orientation together result in an increase inJc by nearly two orders of magnitude. The degradation behaviour was studied in terms of changes inTc,Jc and structure on exposure to atmosphere up to 250 days. Samples with 0.6 Pb were found to be superconducting withTc=97 K even after 250 days. The highTc phase was stable against degradation. Our studies indicate that the degradation of leaded BSCCO is a surface phenomenon rather than bulk phenomenon.

Curie temperature of polycrystalline barium hexaferrite (BaFe12O19), prepared by conventional solid state technique, is anomalously and significantly enhanced (by nearly 15%) by energetic heavy ion irradiation (150 MeV, Ag12+) at ambient temperature due to dense electronic excitations Moderate fluence (1 × 1012 ions/cm2) induces structural defects giving rise to above enhancement. As established by X-ray diffraction, scanning electron microscopy and Raman studies, higher fluence (1 × 1013 ions/cm2) has structurally transformed the sample to amorphous phase with marginal change in magnetization and Curie temperature.

The effect of composition, sintering parameters, frequency and temperature on the dielectric parameters of ZnO-based ceramic semiconductors (cersems) having small amounts of Bi2O3, Sb2O3, CoO, MnO2, La2O3 and/or Cr2O3 has been investigated. The unusually high dielectric constant of these composites, arising due to a two-phase microstructure has been explained on the basis of a depletion layer model. The agreement in values of barrier height and donor concentration calculated fromC −2 −V plot, Hall measurement and I-V characteristics of these cersems supports the validity of barrier and depletion layer models. The depletion and inter-granular layers are estimated to be nearly 102 nm and 1–2 nm respectively. The observed variation of dielectric constant/capacitance with sintering parameters and temperature of measurement has also been explained on the basis of simplified microstructure and depletion layers. The loss peak (f max) observed at 300 kHz remains practically unaltered with change in composition and sintering parameters. The observed dielectric dispersion in the range 102−106 Hz, exhibiting multiple relaxation times and activation energy of relaxation process as 0·36 eV, has been explained on the basis of Debye-type relaxation process originating due to trapping/detrapping and possibly due to scattering of carriers in the depletion regions.

he Fourth General Elections held in February 1967 constitute a watershed in the post-independence political history of India. The monolithic Congress regime and its haloed leadership had concealed both the many operational weaknesses and the basic inner strength and resilience of the Indian system. While strongly reaffirming the people's deep involvement in the democratic process, the electoral verdict shattered the Congress Party's virtual monopoly of political power. It also exposed the artificiality of the political stability, democratic maturity and parliamentary sophistication at which the system had appeared to be operating. Results of the fresh elections held in five of the seventeen States in February 1969 only carried the process a stage further. The most important developments in the post-1967 political and parliamentary scene in India were the formation of coalition governments of widely heterogeneous elements in several States and the numerous defections on the floor of the State legislatures which affected the fate of ministries and the course of politics. This phenomenon, the politics of defection as it is commonly called now, has several psychological and socionomic dimensions and is closely related to the dynamics of human relations and leadership processes. In the present paper, an endeavor has been made to study it objectively, as a psycho-sociological reality, in terms of simple political legitimacy and constitutional legality and in the context of some of the more identifiable legal, political and psychological variables in order to understand its motivations, implications and consequences and more particularly its impact on the problems, processes and prospects of parliamentary democracy in India. Of the sixteen States of the Union that went to the polls in 1967 (there were no elections in Nagaland) the Congress Party did not gain an absolute majority in eight and failed to form the government in seven. Even in those States in which the Congress retained control, its strength was much depleted and in several cases defection by a few members changed the Party's legislative majority into a minority. In seven of the eight States where Congress failed to win an absolute majority, however, no single party took its

Long needle-shaped single crystals of Zn1-xCoxO were grown at low temperatures using a molten salt solvent technique, up to x=0.10. The conduction process at low temperatures is determined to be Mott variable range hopping. Both pristine and cobalt-doped crystals clearly exhibit a crossover from negative to positive magnetoresistance as the temperature is decreased. The positive magnetoresistance of the Zn1-xCoxO single crystals increases with increased Co concentration and reaches up to 20% at low temperatures (2.5 K) and high fields (> 1 T). Superconducting quantum interference device magnetometry confirms that the Zn1-xCoxO crystals are predominantly paramagnetic in nature and the magnetic response is independent of Co concentration. The results indicate that cobalt doping of single crystalline ZnO introduces localized electronic states and isolated Co2+ ions into the host matrix but that the magnetotransport and magnetic properties are decoupled.