Focusing a fountain of neutral cesium atoms with an electrostatic lens triplet

An electrostatic lens with three focusing elements in an alternating-gradient configuration is used to focus a fountain of cesium atoms in their ground (strong-field-seeking) state. The lens electrodes are shaped to produce only sextupole plus dipole equipotentials which avoids adding the unnecessary nonlinear forces present in cylindrical lenses. Defocusing between lenses is greatly reduced by having all of the main electric fields point in the same direction and be of nearly equal magnitude. The addition of the third lens gave us better control of the focusing strength in the two transverse planes and allowed focusing of the beam to half the image size in both planes. The beam envelope was calculated for lens voltages selected to produced specific focusing properties. The calculations, starting from first principles, were compared with measured beam sizes and found to be in good agreement. Application to fountain experiments, atomic clocks, and focusing polar molecules in strong-field-seeking states is discussed.Comment: 8 pages 10 figure

Diversity of wetland fish and its impact on the income of fishermen community of Assam.

A survey was conducted in 3000 fishermen households surrounding 54 wetlands (Beels) of Assam. The fish diversity of the wetlands has been decreasing during the last few years due to some extrinsic and intrinsic factors. The total number of fish species recorded so far during the present study is 67 belonging to 21 families. Cyprinidae is the most dominant family represented by major group species (8), intermediate group species (3) and minor group species (12) of high commercial value. Among these three groups, the diversity of fish species is higher in the minor group fish. The present paper deals with the economic condition of the fishermen who mainly fish in the wetlands. The economic condition of the fishermen community is found very poor. The income of fishermen varies from Rs. 4.478 to Rs.7,484 per annum. A regression analysis shows that the income of fishermen is not dependent alone on the fish production but it is exclusively dependent on the value of the fish catch. All the three groups (in terms of value) have significant influence at 10.00% confidence level. But analysis of β shows that the intermediate fish group exhibits the highest influence on the variation of the fishermen income followed by minor and major group respectively

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

Optimization of dilution rate for the production of value added product and simultaneous reduction of organic load from pineapple cannery waste

Candida utiilis NRRL Y-900 was grown on pineapple cannery waste as the sole carbon and energy source in a chemostat at dilution rates ranging between 0.05 and 0.65 h–1 to determine the growth kinetics. The cell yield coefficient varied with dilution rate and a maximum value of 0.662 ± 0.002 gx/gcarb was obtained at a dilution rate of 0.4 h–1. At steady state, the concentrations of carbohydrate, reducing sugar, and chemical oxygen demand (COD) appeared to follow Monod kinetics. At maximum specific growth rate ( max) 0.65 h–1, the saturation constants for carbohydrate, reducing sugar and COD were 0.51 ± 0.02 gcarb/1, 0.046 ± 0.003 grs/1, and 1.036 ± 0.001 gCOD/1, respectively. Maximum biomass productivity (Q x max) 2.8 ± 0.03 gx/1 h was obtained at a dilution rate of 0.5 h–1. At this dilution rate, only 71.0 ± 0.41% COD was removed whereas at a dilution rate of 0.1 h–1, 98.2 ± 0.35% reduction in COD was achieved. At a dilution rate of 0.4 h–1, the optimal yeast productivity and reduction in COD were 2.7 ± 0.13 gp/1 h, and 84.2 ± 0.42%, respectively. Biomass - Candida utilis - chemostat - continuous culture - growth kinetics - pineapple cannery waste - steady stat

Causes of fish depletion: a factor analysis approach

A study was conducted in 54 wetlands of 13 districts of Assam, India to evaluate the causes of fish depletion. Twenty-two variables were considered for the study. Seven factors were extracted through factor analysis (Principal Component Analysis) based on Eigen Value Criteria of more than one. These seven factors together accounted for 69.3% of the total variance. Based on the characteristics of the variables, all the factors were given descriptive names. These variables can be used to measure the extent of management deficiency of the causes of fish depletion in the wetlands. The factors are management deficiency, organic load interference, catchment condition, extrinsic influence, fishermen’s ignorance, external environment and aquaculture program. Management deficiency accounted for a substantial portion of the total variance

Nonlinear dynamics in an alternating gradient guide for neutral particles

Neutral particles can be guided and focussed using electric field gradients that focus in one transverse direction and defocus in the other, alternating between the two directions. Such a guide is suitable for transporting particles that are attracted to strong electric fields, which cannot be guided using static fields. Particles are only transmitted if their initial positions and transverse speeds lie within the guide's phase space acceptance. Nonlinear forces are always present in the guide and can severely reduce this acceptance. We consider the effects of the two most important nonlinear forces, a term in the force that is cubic in the off-axis displacement, and a nonlinear term which couples together the two transverse motions. We use approximate analytical techniques, along with numerical methods, to calculate the influence of these nonlinear forces on the particle trajectories and on the phase space acceptance. The cubic term alters the focussing and defocussing powers, leading either to an increase or a decrease of the acceptance depending on its sign. We find an approximate analytical result for the phase space acceptance including this cubic term. Using a perturbation method we show how the coupling term leads to slow changes in the amplitudes of the transverse oscillations. This term reduces the acceptance when it reduces the focussing power, but has little influence when it increases that power. It is not possible to eliminate both nonlinear terms, but one can be made small at the expense of the other. We show how to choose the guide parameters so that the acceptance is optimized.Comment: 31 pages, 12 figure

INVESTIGATING THE ROLE OF NF-κB, COX-1, COX-2, COMT, IL-10, IL-6 AND TNF-α IN MODULATING ANTI-NOCICEPTIVE ACTIVITY OF METHANOLIC EXTRACT OF ENTADA PHASEOLOIDES

Objective: To investigate the analgesic activity of methanolic extract of Entada phaseoloides (MEEP) along with its molecular mechanistic pathway. Methods: Swiss albino female mice and Wistar rats of either sex were administered orally with MEEP extracts (100, 200 and 400 mg/kg) and pentazocine, tramadol and diclofenac sodium, as standard drugs. Following administration, anti-nociceptive activity was evaluated using an acetic acid-induced writhing test, Eddy’s hot plate, and hot water immersion test. Serum was collected for molecular expression of various proteins and genes using Reverse Transcriptase PCR and Western Blotting. Results: Acetic acid writhing test, a frequently used method to assess peripheral analgesic activity, revealed that MEEP reduced peripherally induced pain in a dose-dependent manner. Likewise, Eddy’s hot plate and hot water immersion methods, often implicated for testing central analgesic activities, showed that MEEP is bestowed with the capability to counteract analgesia in a dose and time-dependent manner. Pro-inflammatory cytokines and factors like COX-2, IL-6, TNF-α, and NF-κB that cause inflammatory responses and pain were significantly reduced, suggesting its analgesic and anti-inflammatory potential. This analgesic and the anti-inflammatory role played by MEEP is also supported by the up-regulation of anti-inflammatory cytokine IL-10 and COMT and COX-1 enzyme demonstrated no significant difference between the groups. Conclusion: The study revealed the weak peripheral and potent central analgesic property MEEP by modulating pro-inflammatory and anti-inflammatory pathways

Synopsis of marine prawn fishery of India-1981

Prawn landings and percentage contributions of different maritime states in India mainly Gujarat, Maharashtra, Goa, Karnataka, Kerala, Tamil Nadu, Pondicherry, Andhra Pradesh, Orissa, West Bengal and Andamans were studied during 1980 and 1981.The penaeid and non-penaeid prawn landings of the same period in these states were also recorded. Monthlv prawn landings, Penaeid and non-penaeid prawn landings in these states during the year 1981 were studied.Species wise break up of prawn landings and percentages during 1981 were recorded in the present paper. Annual percentage distribution datas of important species in the prawn landings at different centres are given.Prawn landings by commercial shrimp trawlers in relation to the total prawn catch and the fishing effort during 1981 were studied and recorded. Catch trend, species composition and size distribution of important species of prawns at Veraval,Bombay, Karwar, MaIpe and Mangalore, Calicut and Cochin,Neendakara, Waltair, Puri, Kakinada, Tuticorin, Mandapam and Madras during 1981 were extensively studied and recorded. Distribution of the spawning population of important species at selected centres during 1981 were also given

Larval rearing of seahorse Hippocampus kuda under laboratory conditions

Seahorse belongs to a single genus Hippocampus of the family Syngnathidae. This family also includes pipefishes and pipehorses. There are about 30-40 species of seahorses under the genus Hippocampus. They constitute a fascinating group of fishes with their unusual body shape apart from their peculiar mode of reproduction with the males incubating the fertilised eggs in a brood pouch on the abdomen. They are tropical and sub tropical in distribution and are exploited around the world for use in medicines, as ornamental fishes, curios and to a very limited extent as food. Most of them are marine, inhabiting coral reefs and sea grass beds though some occur in coastal mangroves

Evaluation of sampling gear for demersal resource surveys

The three demersal trawls evaluated were 38 m HSDT-II, indigenously developed by CIFT for deep sea fishing in Indian EEZ; and two imported designs, viz., 45.6 m Expo model demersal trawl and 50 m fish trawl operated from vessels of FSI and IFP, respectively. Vertical opening at trawl mouth was heighest for 50 m fish trawl (3.2 m), followed by Expo model demersal trawl (2.5 m) and 38 m HSDT-II (2.2 m), due to differences in overall dimensions and design features. Estimate of horizontal opening between otter boards was highest for 38 m HSDT-II probably due to low drag of the gear, followed by 45.6 m and 50 m trawls. Lowest catch per unit effort obtained by 38 m HSDT-II is presumably due to smaller dimensions of the gear, larger codend mesh size and difference in ground rig, in addition to chance factors. However, 38 m HSDT-II scores on several features desirable in demersal sampling gear such as simplicity in design and construction, ease of operation; lower twine surface area and drag; and ground rig suitable for wider range of bottom conditions. Modifications to make it more effective while sampling for crustaceans and small sized finfish components are described