The pockels' effect in langmuir-blodgett films

Simple, compact and inexpensive automated apparatus for recording surface plasmon resonance and the Pockels (or linear electro-optic) effect in Langmuir-Blodgett films has been used to estimate the thickness, permittivity and second order non linear susceptibility X(^(2))(_xxx)(-w;w,0) of several novel Langmuir-Blodgett film-forming materials. The results agree with estimates of nonlinear susceptibility obtained by second-harmonic generation. The materials synthesised at Durham were all functionalised diaryl alkynes of the general formula CH(_3)(CH(_2))(_n)(Py(^+))C=C(Ph-R), wherein n =17 or 21 and R=H or OCH(_3). Of these, that with n =21 and R=OCH(_3) showed particularly promising Langmuir-Blodgett film-forming properties; its nonlinear susceptibility per mono layer, however, was approximately one hundredth that of a hemicyanine monolayer. The nonlinear susceptibility per monolayer, as measured by the Pockels effect and second harmonic generation, was inversely proportional to the square root of the film thickness. This indicated rapid deterioration of in-plane order with increasing film thickness. Several novel polymeric materials synthesised at Hull and examined at Durham consisted of a siloxane spine of approximately 16 Si atoms, with randomly substituted bipolar chromophoric sidegroups. All were highly stable in floating film form. Of them, one known as AMCR23 showed promising optical nonlinearity when deposited on silver: a nonlinear susceptibility of-15+9.6i pm V(^-1) was recorded for a monolayer (cf. 94.5+49.9i pm V(^-1) for a hemicyanine monolayer)

Shape-induced phenomena in the finite size antiferromagnets

It is of common knowledge that the direction of easy axis in the finite-size ferromagnetic sample is controlled by its shape. In the present paper we show that a similar phenomenon should be observed in the compensated antiferromagnets with strong magnetoelastic coupling. Destressing energy which originates from the long-range magnetoelastic forces is analogous to demagnetization energy in ferromagnetic materials and is responsible for the formation of equilibrium domain structure and anisotropy of macroscopic magnetic properties. In particular, crystal shape may be a source of additional uniaxial magnetic anisotropy which removes degeneracy of antiferromagnetic vector or artificial 4th order anisotropy in the case of a square cross-section sample. In a special case of antiferromagnetic nanopillars shape-induced anisotropy can be substantially enhanced due to lattice mismatch with the substrate. These effects can be detected by the magnetic rotational torque and antiferromagnetic resonance measurements.Comment: 7 pages, 5 figures, to appear in Phys. Rev. B, v.75, N17, 200

Research Notes : India : Effect of dates of planting on five soybean varieties

Assam is one of the seven states comprising the North Eastern region of India. The plains of the Brahmaputra Valley lie between 24° to 28° N Latitude, 90° to 96° East Longitude and its elevation (above M.S.L.) ranges from 35 m (Dhubri) to 106 m (Dibrugarh). Soybean was introduced in Assam in 1975 through the Soy~ean Research Project sponsored by the Indian Council of Agriculture Research, New Delhi

Eating from the wild: an insight into the indigenous wild edible plants consumed by the Digaru Mishmi tribe of Arunachal Pradesh

Anjaw district is situated at the extreme foothill of eastern himalaya of Arunachal Pradesh, distinctive in its nature by having a rich diversity of wild edible plants rich in nutrition as well as medicinal properties. Ethnically, the Digaru Mishmi tribe (inhabitants) of the district adopted the traditional way of consuming these rich ethnobotanical resources to fulfill their daily nutrition & health care. These plants have traditionally occupied an important position in their socio-cultural, spiritual and health aspects of the rural tribal lives. So, the consumption of wild edible plants as a food source has been an integral part of the indigenous people’s culture. To get an insight into the Digaru Mishmi people’s way of lifestyle, the present study was conducted to explore, identify & document the ethno botany of the Digaru Mishmi people and to record their unique knowledge about wild edible plants. Around 57 species were found & all the plants used by the tribe are tabulated inalphabetical order along with botanical name, vernacular name (Digaru Mishmi), family, parts used, food value and ethnomedicinal uses. Wild edible plants form a good source of protein, fat, vitamins, sugar and minerals requirement of the tribal people to a greater extent. Hence, the paper highlights the identification diversity of wild edible plants andits documentation

A comparison of clinical and radiological findings in adults and children with Japanese encephalitis

Background: Japanese encephalitis (JE) is the most common human endemic encephalitis, prevalent mainly in Southeast Asia. It affects both adults and children in different areas, but there is no comparative study of their clinical features and outcomes. Objective: To evaluate clinical and radiological features in adults and children with JE. Methods: Patients with serologically or virologically confirmed JE who were treated during the past 10 years were included in this study. All patients underwent a detailed neurological examination, computed tomography, or magnetic resonance imaging. The presence of movement disorders, anterior horn cell involvement, and electroencephalographic changes was noted. After 6 months, each patient's outcome was defined as poor, partial, or complete recovery. The clinical and radiological findings for both adults and children were compared using χ2 tests. Results: The results are based on 30 children and 37 adults. Seizure was present in 23 adults (62.2%) and in 17 children (56.7%). Three children had associated neurocysticercosis, and all of them had partial seizures. The occurrence of focal neurological deficit, anterior horn cell involvement, and parkinsonian features was not significantly different between adults and children. Dystonia was more common in children, occurring in 20 (66.7%) compared with 7 adults (18.9%). Six adults died, but none of the children did; however, the 6-month outcome was better for surviving adults compared with the children. Computed tomography and magnetic resonance imaging findings were not significantly different between the 2 groups. Conclusions: Children with JE are more likely to have dystonia and a poor outcome at 6 months compared with adults. The difference in clinical findings and outcome in children and adults with JE may be owing to immunological factors, maturation of the central nervous system, and neuronal plasticity

Dependence of the 0.5(2e2/h) conductance plateau on the aspect ratio of InAs quantum point contacts with in-plane side gates

The observation of a 0.5 conductance plateau in asymmetrically biased quantum point contacts with in-plane side gates has been attributed to the onset of spin-polarized current through these structures. For InAs quantum point contacts with the same width but longer channel length, there is roughly a fourfold increase in the range of common sweep voltage applied to the side gates over which the 0.5 conductance plateau is observed when the QPC aspect ratio (ratio of length over width of the narrow portion of the structure) is increased by a factor 3. Non-equilibrium Green s function simulations indicate that the increase in the size of the 0.5 conductance plateau is due to an increased importance, over a larger range of common sweep voltage, of the effects of electron-electron interactions in QPC devices with larger aspect ratio. The use of asymmetrically biased QPCs with in-plane side gates and large aspect ratio could therefore pave the way to build robust spin injectors and detectors for the successful implementation of spin field effect transistorsComment: 30 pages, 9 figure

‘Kamrupa’-A new dual chicken variety for farmers of Asom and North-East India

A dual type multicolored new variety of chicken was developed by crossing Indigenous birds of Asom with a broiler parent PB-2, and a layer parent Dahlem Red, procured from Directorate of Poultry Research, Hyderabad. The present study aimed to study productive and reproductive performance of this variety under intensive and free range system in rural areas of Asom. During the study, body weights of the birds at all stages of growth reared under intensive rearing system were significantly higher than the free range system. The shank length, keel length and breast angle were recorded as 3.98±0.64 cm, 3.21±0.25 cm and 63.75±2.23 degree in intensive system and 4.31±0.98 cm, 3.88±0.76 cm and 62.35±2.54 degree in free range system, respectively. The pullet matured by 20.83 days earlier and laid 20.40 more eggs annually in intensive system compared to that of free range system. The egg weight at 32 weeks and 40 weeks were higher by 1.70 g and 2.66 g in intensive system than that of free range system. The egg quality traits, viz. shape index, albumin index, yolk index, Haugh unit, shell thickness and fertility and hatchability were better in free range system than that of intensive system. Most of the carcass characteristics and survivability of Kamrupa bird were slightly better in intensive system than that of the free range system. From economic point of view, Kamrupa bird’s performance is slightly better in free range system than that of the intensive system

Image of The Communist Party of The Russian Federation as Viewed by Russian Students: Factor Semantic Reconstruction

The article presents the results of the semantic reconstruction of the image of a political party (the Communist Party of the Russian Federation) as viewed by students of classical and technical universities. This reconstruction allows determining the structure of political thinking typical of the Russian youth. To study students' beliefs and ideas, the authors of the article use the method of semantic differential. The article is based on a unipolar 50-scale semantic differential entitled "political party" and developed by V.V. Kalita and E.B. Marin to evaluate the properties of political parties. The evaluation results were subject to factor analysis in conformity with the method described by V.P. Serkin. The factor analysis of the data determines the evaluation structure used by respondents in relation to the Communist Party of the Russian Federation. The key axes for evaluating parties are the axes of "pride" and "fear". They contain basic criteria for evaluating parties. These axes, or evaluation criteria, reflect the key categories of political thinking common to the Russian youth. The study results can help develop youth policies of parties and government, as well as contribute to the further study of political ideas common to the Russian youth