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The present paper discusses a general expression for determining the minimum sample size (plants) for a given number of seeds or vice versa for capturing multiple allelic diversity. The model considers sampling from a large 2 k-ploid population under a broad range of mating systems. Numerous expressions/results developed for germplasm collection/regeneration for diploid populations by earlier workers can be directly deduced from our general expression by assigning appropriate values of the corresponding parameters. A seed factor which influences the plant sample size has also been isolated to aid the collectors in selecting the appropriate combination of number of plants and seeds per plant. When genotypic multiplicity of seeds is taken into consideration, a sample size of even less than 172 plants can conserve diversity of 20 alleles from 50,000 polymorphic loci with a very large probability of conservation (0.9999) in most of the cases.

Bitter gourd (Momordica charantia L, family Cucurbitaceae) is a major vegetable crop widely cultivated throughout India. Bitter gourd pods are consumed for their nutritional and medicinal value. In 2016, nearly 15% of plants showed virus-like symptoms in a 0.6 ha bitter gourd farm at the Indian Institute of Vegetable Research, Varanasi, Uttar Pradesh, India. Symptomatic plants were stunted with necrosis of growing tips and yellowing and downward cupping of leaves that became thick and leathery in appearance. Since these symptoms were like those produced by orthotospoviruses in vegetable crops (Kunkalikar et al., 2011), leaves from five symptomatic and five non-symptomatic plants were initially tested by indirect ELISA using polyclonal antibodies raised against Peanut bud necrosis virus (PBNV; Genus: Orthotospovirus; Family: Tospoviridae). These antibodies were obtained from the International Crops Research Institute for the Semi-Arid Tropics, Hyderabad, India. Only samples from symptomatic plants gave pos...

Proline (Pro)-rich proteins (PRPs), initially identified as structural proteins of cell wall, have emerged as multifunctional plant proteins in recent past. Their vibrant role in plant development and environmental stress promoted us to study a SlPRP gene of tomato, which was significantly downregulated under drought stress in a microarray experiment performed in our laboratory. Promoter analysis of SlPRP revealed a number of stress-responsive protein-binding sites, confirming its expression in response to stress. Expression of SlPRP gene in different tissues of tomato, viz. root, stem, leaf and flower was studied to analyse the gene expression pattern in response to drought stress. Further, we have correlated the expression of SlPRP gene with Pro levels of the respective plant tissues under drought stress. In anticipation, it has been observed that downregulation of SlPRP gene is coupled with simultaneous increase in cellular Pro concentration in all the tissues under drought stress, except the roots. This could help preserve the available cellular proline to function as osmoprotectant during stress. The present results propose a hypothesis where PRPs may regulate free cellular proline levels during drought stress by regulating their own gene expression. Thus, it may be concluded that transcription of PRPs in plants is synchronized with the cellular Pro concentration under environmental stress in order to provide drought tolerance to plants.

FIXED POINTS OF A PAIR OF MAPPINGS

This paper presents a new algorithm for the simultaneous computation of gravity and magnetic anomalies resulting from an infinitely long (2‐D) body with an arbitrary polygonal cross‐section. With the assumption of uniform volume density and magnetization, the gravity or magnetic field may be expressed as the field resulting from an equivalent distribution of surface mass density or surface pole density, respectively, over the surface of the source body. The resulting surface integrals are reduced to new line integrals using Stokes' theorem. The components of the fields for each bounding surface are expressed in terms of a new line integral and the solid angle subtended by the surface at the point of observation. Since these analytical solutions are similar in form, a direct relation is derived between gravity and magnetic fields, which allows their simultaneous computation. Hence, the same computer program can be used to compute the gravity field, the magnetic field, or both fields simultaneously. This new approach will find wide applications in the joint inversion of potential field data, as it will make the numerical computations much faster.

We show that at any point the gravity field from a solid body bounded by plane surfaces and having uniform density can be computed as a field from a fictitious distribution of surface mass‐density on the same body. The surface mass density at every surface element is equal to the product of the volume density of the body and the scalar product of (1) the unit outward vector normal to that surface element and (2) the position vector of the surface element with respect to the point of observation. Accordingly, the contribution to the gravity field from any plane surface of the body vanishes if the observation point lies in the plane of that surface. As a result, we can compute the gravity field everywhere, including points inside, on the surface, on an edge, or at a corner of the body where more than two surfaces meet. This new result lets us compute the gravity field using exactly the same simple procedure as for the magnetic field of a uniformly magnetized object, computed from an equivalent surface distribution of magnetic pole density. To get the gravity field while computing the magnetic field, one simply uses the product of this surface mass density and the universal gravitational constant instead of the surface magnetic pole density. Therefore, the same computer program can be used to compute the gravity, the magnetic field, or both simultaneously. This simple and novel approach makes the numerical computations much faster than all other previously published schemes.

The Aravalli Delhi Mobile Belt (ADMB) in NW India includes the Proterozoic Aravalli and Delhi rifts and fold belts. A seismic profile and gravity modelling across the ADMB shows several dipping reflections and suggests a thick crust (45–46 km) and a high density (3.04 g cm−3) dome-shaped body in the lower crust. This high density body in the lower crust may represent underplated lower crust caused by extension during evolution of the Proterozoic rifts. Part of the gravity high observed over the ADMB is attributed to the upthrust blocks of high density lower crustal granulite rocks. The gravity low along the eastern margin of the ADMB is modelled as being due to a westerly dipping (45°) low density body in the crust, in accordance with seismic reflectors which may represent remanents of the subducted crustal rocks. The Hindoli group of rocks above this body is characterized by high conductivity, indicating a high fluid content and a fractured nature which may be related to the collisional tectonism of this region. A sharp gravity high along the western margin of the ADMB is attributed to the basic rocks of an ophiolite melange. The gravity low and high west of the ADMB are attributed to plutonic activity and bimodal calc-alkaline volcanics in linear basins and are related to arc and back-arc rift magmatism, respectively. The ADMB, therefore, represents a Proterozoic collision zone between the Bundelkhand craton towards the east and the Rajasthan craton towards the west with a plausible subduction towards the west along the eastern margin of the ADMB. The thrusting is mainly confined to the obducted block towards the west, although some thrusting is inferred even in the subducted block. The central Indian Suture (CIS) is located at the southern margin of the Satpura Mobile Belt (SMB) in central India and separates high grade metasediments and granulite towards the north from low grade Proterozoic volcanogenic successions towards the south. A seismic profile and gravity modelling across the CIS show a thick crust with a thicker crust north of the CIS compared to the south and a contact in the lower crust whose projection on the surface coincides with the CIS. The CIS at the surface coincides with a low density (2.65 g cm−3) and conductive body that is interpreted to be fluid-filled and fractured in nature. The high density (2.81 g cm−3) body modelled in the upper crust north of the CIS coinciding approximately with a highly conductive body and dome-shaped seismic reflectors may represent an upthrust block from the lower crust as high density granulite rocks are exposed in this region. Short wavelength gravity highs and lows south of the CIS represent exposed metavolcanics and granite intrusions which represent tholeiitic series rocks to calc-alkaline series rocks associated with island arcs and back arc magmatism. Therefore, the large wavelength gravity low south of the CIS is modelled as a low density body below the Moho, which conforms with seismic reflectors and may represent crustal rocks subducted towards the south. Thrusting in this case is indicated in the subducted block towards the north of the CIS. The bipolar gravity anomaly across the CIS, therefore, indicates a collision zone between the Bundelkhand craton towards the north and Bhandara–Deccan cratons towards the south.

The magnetic field at any point outside a uniformly magnetized polyhedron of arbitrary shape is obtained by adding the fields resulting from the effective free magnetic poles on each of the polygonal surfaces of the polyhedron. For each polygonal surface, the components of the field at the point of observation are expressed in terms of new line integrals around the edges of the polygon and the solid angle subtended by the polygon at the point of observation. The line integrals are standard elementary forms. This new approach makes the numerical evaluation of the magnetic fields for such models much simpler and faster than previously published methods.

Monsoon rainfall over Indian subcontinent causes large hydrological changes that deform the earth on varied time scale. The seasonal hydrological mass changes are in the range of 20–50 cm of equivalent water height over southern India, which causes vertical deformation of 1–2 cm. We compare the deformation computed from GRACE mass signal with that of height changes from continuous GPS data from two locations in south India and find that the amplitude and phases of seasonal vertical deformation derived from both (GPS and GRACE) are consistent, indicating that hydrological effects are major cause of periodic deformation in the region. This supports the earlier deduction that GRACE data can be utilized to remove hydrological effects from GPS data. High precision absolute gravity values measured near the GPS location and groundwater levels measured in the boreholes corroborate the space based observations of hydrological changes and vertical deformation. GPS and GRACE data also indicate inter-annual variation caused due to rainfall variability, signifying that hydrological effects must be removed before deriving any long term vertical deformation trend.

The numerical evaluation of certain integral transforms is required for the interpretation of some geophysical exploration data. Digital linear filter operators are widely used for carrying out such numerical integration. It is known that the method of Wiener–Hopf minimization of the error can be used to design very efficient, short digital linear filter operators for this purpose. We have found that, with appropriate modifications, this method can also be used to design longer filters. Two filters for the Hankel J0 transform (61-point and 120-point operators), and two for the Hankel J1 transform (47-point and 140-point operators) have been designed. For these transforms, the new filters give much lower errors compared to all other known filters of comparable, or somewhat longer, size. The new filter operators and some results of comparative performance tests with known integral transforms are presented. These filters would find widespread application in many numerical evaluation problems in geophysics.

A novel multiplexed scheme is demonstrated to combine two or more pulsed solid state pulsers of moderate capabilities. Pulse power supply comprising of two solid state pulsers of ∼6 kW rating each in multiplexed mode with common magnetic pulse compression stage was demonstrated and optimized for operating with a wide aperture kinetically enhanced copper vapor laser. Using this new configuration, the multiplexed pulsed power supply was capable of operating efficiently at net repetition-rate of ∼13 kHz, 12 kW (wall plug average power), 18–20 kV discharge voltage and pulse rise-time of ∼80 ns. The laser under multiplexed configuration delivered un-interrupted output power of about ∼80 W with scope of further increase in laser output power in excess of 100 W.

Sequences have been fascinating topic for mathematicians for centuries. Fibonacci sequence, Lucas sequence, Pell sequence, Pell-Lucas sequence, Jacobsthal sequence and Jacobsthal-Lucas sequence are most prominent examples of second order recursive sequences. In this paper, companion Fibonacci-Like sequences are introduced and presented generalized identities of companion Fibonacci-Like sequences with Jacobsthal and Jacobsthal-Lucas sequences.

The Fibonacci and Lucas sequences are well-known examples of second order recurrence sequences, which belong to particular class of recursive sequences. In this article, Fibonacci-Like sequence is introduced and defined by 1 2 0 1 2 for 2 with 2 , 1. n n n H H H n H H        The Binet’s formula and generating function of Fibonacci-Like sequence are presented with some identities and connection formulae.

Drought (soil and/atmospheric water deficit) is the most environmental constraints among abiotic stresses. Cowpea is inherently more drought tolerant than other vegetables, but it also suffers to a considerable yield loss when the moisture deficit is imposed during flowering and pod setting. The experiment was carried out at IIVR, Varanasi during spring-summer of 2012 and 2013. A total of 29 diverse cowpea genotypes, comprising of vegetable and grain types were selected for study. Drought stress was imposed 35 days after sowing by withholding the irrigation for 25 days. All genotypes were also kept under well watered control. Experimental findings revealed that under drought stress, some genotypes, viz., EC-30590, EC-37988, EC-390241, EC-15296, EC-472283 and Gomti expressed significantly higher relative leaf water content (>80%), photosynthesis (14.7 to 18.2 μmol m−2 s−1), stomatal conductance (0.443 to 0.818 μmol m−2 s−1), quantum yield of PSII photochemistry, i.e. Fv/Fm (0.467 to 0.727) and transpiration rate (0.0321 to 0.0467). These genotypes also showed less yield anddry matter reduction under drought stress as compared to susceptible cultivars/genotypes. The commercialcultivars such as, Akra Garima, Kashi Nidhi, Kashi Shyamal and Kashi Kanchan were found more susceptibleto drought. It may concluded that genotypes EC-30590, EC-37988, EC-390241, EC-15296, EC-472283 and Gomtiwere fairly drought tolerant, and may be utilized for cultivation under water limited condition or for breeding ofdrought tolerant cultivars.

International audience; For the present 2-D lithospheric density modelling, we selected three geotransects of more than 1000 km in length each crossing the southern Indian shield, south of 16 degrees N, in N-S and E-W directions. The model is based on the assumption of local isostatic equilibrium and is constrained by the topography, gravity and geoid anomalies, by geothermal data, and where available by seismic data. Our integrated modelling approach reveals a crustal configuration with the Moho depth varying from similar to 40 km beneath the Dharwar Craton, and similar to 39 km beneath the Southern Granulite Terrane to about 15-20 km beneath the adjoining oceans. The lithospheric thickness varies significantly along the three profiles from similar to 70-100 km under the adjoining oceans to similar to 130-135 km under the southern block of Southern Granulite Terrane including Sri Lanka and increasing gradually to similar to 165-180 km beneath the northern block of Southern Granulite Terrane and the Dharwar Craton. This step-like lithosphere-asthenosphere boundary (LAB) structure indicates a normal lithospheric thickness beneath the adjoining oceans, the northern block of Southern Granulite Terrane and the Dharwar Craton. The thin lithosphere below the southern block of Southern Granulite Terrane including Sri Lanka is, however, atypical considering its age. Our results suggest that the southern Indian shield as a whole cannot be supported isostatically only by thickened crust; a thin and hot lithosphere beneath the southern block of Southern Granulite Terrane including Sri Lanka is required to explain the high topography, gravity, geoid and crustal temperatures. The widespread thermal perturbation during Pan-African (550 Ma) metamorphism and the breakup of Gondwana during late Cretaceous are proposed as twin cause mechanism for the stretching and/or convective removal of the lower part of lithospheric mantle and its replacement by hotter and lighter asthenosphere in the southern block of Southern Granulite Terrane including Sri Lanka. Unusually thinned LAB beneath the region near Bangalore apparently indicates the preserved tectonocompositional effect of late Proterozoic rifted margin of Dharwar Craton.

One of the most important objectives of the goals of Millennium Development Goals is to eradicate extreme poverty and hunger. Sufficient nourishment for the whole population of the world is one of the challenges of the present era. According to an estimate plant parasitic nematodes are causing much more damage annually compared to insect pests. A crop yield loss due to these tiny unseen pests in various countries is enormous. They caused projected yield loss of 12.3% ($157 billion dollars) worldwide. Out of which $40.3 million is reported from India. Farmers/growers identified insect pests, and other constraints as production problems but overlooked plant parasitic nematodes. Nematode diseases are difficult to control because of their hidden nature and hence, more often overlooked. Plant parasitic nematodes not only cause damage individually but form disease-complexes with other micro-organism and increased the crop loss. Also the symptoms of nematode damage are not specific, resemble with the symptoms of other pathogens and abiotic stresses such as water and mineral deficiency. Future agricultural growth must come from productivity growth to address the persistent problems of poverty, food insecurity and malnutrition. Recommended measures against nematode diseases include use of clean nematode free planting material, resistant varieties, and crop rotations to suppress nematode infestation. Integrated nematode management can be promoted through farmers-nematologists interactions, local production of bio-control agents and strict chemical pesticide regulations. Farmer's/grower's awareness and skills are equally important in minimizing nematode infestation and yield losses, to sustain the agriculture production.

Background The rapidly growing availability of diverse full genome sequences from across the world is increasing the feasibility of studying the large-scale population processes that underly observable pattern of virus diversity. In particular, characterizing the genetic structure of virus populations could potentially reveal much about how factors such as geographical distributions, host ranges and gene flow between populations combine to produce the discontinuous patterns of genetic diversity that we perceive as distinct virus species. Among the richest and most diverse full genome datasets that are available is that for the dicotyledonous plant infecting genus, Begomovirus, in the Family Geminiviridae. The begomoviruses all share the same whitefly vector, are highly recombinogenic and are distributed throughout tropical and subtropical regions where they seriously threaten the food security of the world's poorest people. Results We focus here on using a model-based population genetic approach to identify the genetically distinct sub-populations within the global begomovirus meta-population. We demonstrate the existence of at least seven major sub-populations that can further be sub-divided into as many as thirty four significantly differentiated and genetically cohesive minor sub-populations. Using the population structure framework revealed in the present study, we further explored the extent of gene flow and recombination between genetic populations. Conclusions Although geographical barriers are apparently the most significant underlying cause of the seven major population sub-divisions, within the framework of these sub-divisions, we explore patterns of gene flow to reveal that both host range differences and genetic barriers to recombination have probably been major contributors to the minor population sub-divisions that we have identified. We believe that the global Begomovirus population structure revealed here could facilitate population genetics studies into how central parameters of population genetics namely selection, recombination, mutation, gene flow, and genetic drift shape the global begomovirus diversity.

Large-bore kinetically enhanced copper vapor laser (CVL) based on new thermal assembly consisting of different density zones of insulation material (alumina fiber) around the discharge tube is demonstrated for the first time with efficiency etaor = 1% at extremely low specific input power (SIP) ofor = 1 kW/l. As a result of this longitudinal profiling of the insulation material, efficiency of approximately 1.2% was achieved at lowest SIP of approximately 0.75 kW/l. Net reduction in the input power of approximately 1 kW was observed on using this thermal assembly as compared to nonprofiled thermal assembly. These results show significant improvement (25%-30%) at low input requirements of the laser on using new thermal assembly around the discharge tube with overall electro-optical efficiency etaor = 1%. Maximum laser power achieved from the laser was approximately 78 W at approximately 9.8 kHz rep rate with efficiency of approximately 1.4%. This large-bore CVL is also capable of operating efficiently (eta approximately 1%) at high rep rate of -17 kHz with maximum laser power of approximately 50 W. Performance of the laser under various operating conditions is also presented in this short paper.

Evidence of Economic Heterosis and Genetic Control of Fruit Yield and Yellow Vein Mosaic Virus Disease Severity Traits of Okra) Ten diverse genotypes of cultivated and wild species were crossed in half diallel fashion to produce 45 F1 hybrids to determine mode of gene action, extent of economic heterosis and dominance effect, and to estimate combining ability for eight quantitative traits. Predictability ratio revealed overwhelming response of non-additive gene action for controlling fruit length, number of fruits per plant, and fruit yield per plant; additive gene effects for days to 50% flowering, while both additive and non-additive genetic control for node number at first flowering, fruit weight, fruit girth, and PDI of YVMV disease. Appropriate breeding strategies for improvement of studied traits are highlighted here. Significant standard heterosis over two commercial hybrids, Shakti and Abantika was comparatively lower in magnitude for fruit yield per plant (4.62 % and 17.59 %, respectively) and higher in magnitude for PDI of YVMV disease (-71.28 % and -72.28 %, respectively). Partial- to overdominance effects were involved in the inheritance of the studied traits. BCO-1 and 11/RES-6 were identified as potential donors for future use. The study could able to identify an outstanding hybrid (BCO-1 × Arka Anamika) having high tolerance both under field and artificial conditions. This hybrid would definitely make a room in okra growing zones of the tropics after critical testing..

[1] Height and gravity measurements observed along a profile across the epicentral area before and after the January 26, 2001, Mw 7.6 Bhuj earthquake show a maximum uplift of 1.57 ± 0.5 m and a corresponding gravity change of −393 ± 18 μGal. A best-fit, single-dislocation model inverted from the height-changes using non-linear optimization methods indicates that the high-slip rupture was well contained in the aftershock zone and likely did not break to depths shallower than ∼10 km. Source parameters arrived in the present study agree well with those provided by seismic inversions and the distribution of aftershocks. Gravity data over the epicentral area are well modeled by the preferred model; however, a strong influence of shallow hydrological processes is inferred for three sites, two located on the Banni plains, whose mean gravity change ∼280 μGal suggests a total mass redistribution of as much as 2.9 Mt.

The experiment was conducted during kharif 2010-2011 with 41 genotypes of soybean to study genetic variability, correlation and path coefficient analysis of yield and its component characters. In general, PCV were higher than the GCV values for all the characters. The broad sense heritability estimates were high for all the 9 characters. Correlation and path coefficient analysis for seed yield/plant and its components indicated that out of 9 characters, seed yield/plant showed positive and significant association with biological yield, pods per plant and 100-seed weight indicating that an intense selection for these characters will improve seed yield in soybean. Path coefficient analysis revealed that biological yield, number of pods per plant and 100 seed weight were major characters influencing seed yield directly and indirectly. The results indicated that biological yield is responsible for manipulation of seed yield in soybean.

Commentaire et reponse concernant l'article de R. K. FROHLICH (1989) - Tectonophysics, 163, 1-12.

One of the simplest and more studied integer sequences is the Fibonacci sequence. Fibonacci sequence is famous for possessing wonderful and amazing properties. The Fibonacci sequence has been generalized in many ways, some by preserving the initial conditions and others by preserving the recurrence relation. In this paper, generalized Fibonacci sequence is introduced and defined by

A copper vapor laser based on the use of copper chloride and silver chloride mixture embedded inside the laser head thermal insulation is successfully demonstrated. The use of external HCl generator cell containing zirconium chloride normally used for its kinetically enhanced mode of operation is completely eliminated. With this new configuration laser power of ~70 W was achieved from a wide aperture ~47-50 mm bore discharge tube with input power of ~5 kW and overall high efficiency of ~1.4% without external supply of HCl vapors to the laser head. In a typical operational cycle the laser initially operates as low temperature CuCl laser with startup time of few minutes and output power of ~10 W during low tube temperature range of ~300-500 °C. Thereafter, the laser transforms itself into efficient kinetically enhanced copper vapor laser (CVL) at high temperature range of ~1200-1600 °C with maximum laser output power of ~70 W. This dual mode of operation observed in a single CVL system is unique and has not been reported so far in any high temperature copper vapor laser. New resonator configurations, namely, the prism resonator in stable and unstable form are successfully demonstrated for the first time in a copper vapor laser to achieve low divergence beam with dramatic increase in misalignment tolerance to ~25 mrad, which is an improvement of about ~50 times compared to standard CVLs with conventional spherical or plane-plane resonators. With these new resonator configurations the CVL functions almost as an "alignment free laser" system with significantly reduced beam divergence of ~0.2 mrad and high optical extraction efficiency of ~70%-80%.

An efficient micropropagation protocol was developed using lateral shoot explants of Aloe vera . Both shoot induction and elongation were better on MS medium supplemented with 4mg/l BAP + 0.2mg/l NAA + 1g/l PVP. All cultures showed shoot regeneration in this medium with 16 shoots/explant. Addi-tion of 1g/l PVP was ineffective for controlling phenolic browning of explants and culture discoloration. However, more adventitious buds (21.5 shoots/explant) developed on MS medium supplemented with 4mg/l BAP + 0.2mg/l NAA + 1g/l PVP+10mg/l citric acid+0.5g/l activated charcoal. Browning of ex-plants was minimized in this medium and elongation of micro-shoots and the growth of the plantlets were also better. Further elongation and rooting of micro-shoots were obtained when sub-cultured on to MS basal medium containing 0.5g/l activated charcoal and 100% of the survival of rooted plantlets was observed after acclimatization. Therefore, the above protocol could be effectively used in rapid mi-cropropagation of elite plants of Aloe vera . Key words: Aloe vera , Phenolic browning, Micropropagation, Culture media, Growth hormones DOI: http://dx.doi.org/10.4038/tare.v13i4.3291 TARE 2010; 13(4): 87-93

We report for the first time the performance of axicon based conical resonators (ABCRs) in a copper vapor laser, with novel results. The unstable conical resonator comprising of conical mirror (reflecting axicon) with axicon angle approximately pi/18, cone angle approximately 160 degrees, and a convex mirror of 60 cm radius of curvature was effective in reducing the average beam divergence to approximately 0.15 mrad (approximately 25 fold reduction compared to standard multimode plane-plane cavity) with output power of approximately 31 W. Extraction efficiency of approximately 50%-60% and beam divergence of1 mrad was achieved in other stable ABCR configurations using flat and concave mirrors with the axicon. This is a significant improvement compared to 4-5 mrad normally observed in conventional stable resonators in copper vapor lasers. The conical resonators with copper vapor laser provide high misalignment tolerance beta approximately 4-5 mrad where beta is the tilt angle of the conical mirror from optimum position responsible for approximately 20% decline in laser power. The depth of focus d was approximately three times larger in case of conical resonator as compared to that of standard spherical unstable resonator under similar beam divergence and focusing conditions.

A simple, compact, 60W second generation kinetically enhanced copper vapor laser (KE-CVL) optimized at repetition rate of ∼10kHz is demonstrated using a 25mm bore and a 1m length discharge tube with reduced thermal insulation. Recrystallized alumina tube (45mm bore) is used as an outer enclosure to contain a discharge tube and a thin layer of alumina fibrous thermal insulation for achieving compactness, ruggedness, and reliability in the KE-CVL. Double thyratron pulse modulator has been used for minimizing the switching stresses in the discharge circuit without using snubber circuit and magnetic assist. Specific output power of ∼122W∕liter was achieved with input power of ∼4.5kW and moderate charging voltage of ∼13.5kV (dc supply voltage ∼6.75kV). Specific output energy of ∼12mJ∕cm3 (at 10kHz repetition rate) was achieved as compared to ∼8mJ∕cm3 (at 25kHz) in a 25mm bore KE-CVLs reported previously. The design modifications and KE effects combined are the main reasons for many-fold increase in total outpu...

A wide aperture kinetically enhanced copper vapor laser consisting of a ∼47mm bore and 1450mm length discharge tube is demonstrated with moderate input power of ∼5kW, and overall efficiency of ∼1.45%. The laser pulse durations were observed to be ∼60ns full width at half maximum. An increase in output power from 17to73W at ∼9.4kHz (a factor of ∼4.3) has been achieved due to kinetic enhancement effects in this laser. Output laser pulse shape monitoring was used for optimization of maximum output power from the laser.

Palynological observations on peaty and sandy clay beds of some sedimentary sequences from the Kurunegala district of Sri Lanka reveal the occurrence of plant microfossils of probable Permo-Triassic age. The microfossils are found in sediments considered to be of glacial origin deposited on the Sri Lankan fragment of the Gondwanaland.

The electrical potential due to a point source of current placed on the ground surface is studied for a multi-layered earth consisting of homogeneous overburden of constant conductivity over a stack of transition layers where conductivity varies with depth according to power and exponential laws in even and odd layers, respectively. The general recursion relations are derived and are used to obtain expressions for the apparent resistivities for Schlumberger and Wenner electrode arrays. Their asymptotic behavior has been studied. The solutions for some particular cases are given: (i) odd layers with conductivities exponentially varying with depth while all even layers (and the first) have constant conductivities; (ii) even layer conductivities varying as a power law while odd number layers are of constant conductivity; and (iii) any two successive layers as transition layers and all others having constant conductivities. Further it is shown that Patella's theory is a particular case of the present study. It is concluded, therefore, that the present treatment is more general as all earlier models consisting of trasition layers can be derived from this study.

Ever since the introduction of fuzzy sets by Zadeh [1] , the fuzzyness invaded almost all the branches of crisp mathematics. Deng [3] kaleva and Seikalla [2] and Kramosil and Michalek [5]Have introduced the concept of fuzzy metric space, George and Veeramani [4] modified the concept of fuzzy metric space introduced by kramosil and michalek [5]. In thia paper effort has been made to obtain some results on fixed points of expansion type mapping in Intuitionistic fuzzy metric space DOI: http://dx.doi.org/ 10.3126/kuset.v7i1.5420 KUSET 2011; 7(1): 38-47

The chemistry of bidentate (S,S−) donor ligands 2-amino-1-cyclopentene-1-dithiocarboxylic acid (HL) and itsN-alkyl derivatives [alkyl = Me (HL1), Et(HL2) and Bu(HL3)] with hafnium(IV) chloride in 1∶1, 1∶2, 1∶2, 1∶3 and 1∶4 molar ratios is described. These complexes were characterized by elemental analysis, u.V., i.r. and n.m.r. spectral studies. Disulphur chelation with coordination numbers 5, 6, 7 and 8 was observed in all the metal chelates.

A series of hafnium(IV) complexes has been synthesised by the reaction of hafnium(IV) isopropoxide-isopropanol(1/1) with 2-aminocyclopent-1-ene-1-dithiocarboxylic acids RNHC(CH2)3CC(S)SH, (where R=H, Me, Et or Bu) in 1∶1 and 1 ∶ 2 molar ratios. The compounds have been characterized by elemental analysis, i.r. and1H n.m.r. spectral studies. The complexes polymerise slowly in solution, probablyvia the sulphur atom of the >C=S group.

Hafnium(IV) complexes have been prepared by the reactions of hafnium(IV) isopropoxide isopropanol with Schiff bases [bis(salicylaldehyde)hydrazine] (Sal-AH2), (bis(o-hydroxyacetophenone)hydrazine] (Acp-AH2), [bis(resacetophenone)hydrazine] (Res-AH2), [bis(salicylaldehyde)ethylenediimine) (SaleneH2), [bis(o-hydroxyacetophenone)ethylenediimine] (AcpeneH2) and [bis(salicylaldehyde)o-phenylenediimine] (SalpheneH2) (derived from salicylaldehyde,o-hydroxyacetophenone, resacetophenone and diamines) in appropriate molar ratios using benzene as solvent. The complexes [Hf(OPr-i)2(SB)] and [Hf(SB)2] (where SB2− represents the dianion of the Schiff base) are reported. The complexes of Sal-A, Acp-A and Res-A are 5-and 6-coordinate while those of salene, acpene and salphene are 6-and 8-coordinate. The Schiff bases draw on Sal-A, Acp-A and Res-A are tridentate and salene, acpene and salphene are tetradentate. The mode of bonding through nitrogen and oxygen and the stereochemistry of the complexes are discussed in relation to the elemental analyses and spectra (electronic, infrared and nuclear magnetic resonance).

The ligating properties of 2-iminocyclohexanedithiocarboxylic acid were investigated. Complexes with halides of manganese(II), iron(II), cobalt(II), nickel(II), copper(II), zinc(II), cadmium(II) and mercury(II) were synthesized and characterized by elemental analysis, magnetic measurements, electron and i.r.1H n.m.r. spectral studies. The results are concordant with a bidentate coordination of the—CS2 group to the metal ions.