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Taenia solium cysticercosis is a major public health problem in developing countries. Swine cysticercosis results in economic losses for pig farmers in disease endemic areas. Consumption of cysticercotic pork leads to taeniasis in humans. Eggs excreted in the faeces of T. solium carriers disseminate to humans and pigs through the faecal–oral route, thus maintaining the life cycle in endemic areas. An enzyme-linked immunoelectrotransfer blot (EITB) assay was developed using whole crude T. solium cysticercus antigens (WCA) for the diagnosis of swine cysticercosis. Sera from 30 swine with cysticercosis confirmed by magnetic resonance imaging were subjected to EITB assay. Sera from 50 swine that were raised in a government farm and not allowed to roam freely were included as negative controls. Two or more bands of 8, 11, 14, 24, 26 and 29 kDa were immunoreactive on blot with sera from all infected swine except two, and none from swine raised on the government farm. The overall sensitivity and specificity of EITB assay for diagnosis of swine cysticercosis were 93.3% and 100%, respectively. Hence, EITB assay based on WCA may be a suitable diagnostic tool for swine cysticercosis in endemic areas.
The mathematical model for the propagation of intense laser pulse in a plasma having Gaussian profile is investigated. The model has been formulated considering that the relativistic–ponderomotive nonlinearity dominates over other nonlinearities in the plasma. Model equation for self-compression and self-focusing properties of the laser pulse has been set up and solved by both semi-analytical and numerical methods. The result indicates that due to the effect of group velocity dispersion, diffraction of the laser pulse and the nonlinearity of medium, the pulse width parameter as well as beam width parameter of pulse gets focused at a different normalized distance, and hence the normalized intensity is also deferred at those points. Numerical simulation shows an oscillatory behavior of intensity during propagation in the plasma either having minimum beam radius (r0) or having minimum pulse duration (t0) depending on the normalized distance.
In this presentation, results of our recent investigations on the role of Ga on Al site in Zr69.5Al7.5-xGaxCu12Ni11 and Ce75Al25-xGax metallic glass compositions will be discussed. Ga like Al is normally expected to be in trivalent state. However, it may go in monovalent state depending on other alloying elements. The rapidly solidified melt spun ribbons of above two alloys gave rise to two important conclusions. The Zr69.5Al7.5-xGaxCu12Ni11 system displayed metallic glass formation in the range of x=0 to 7.5. In this process, we have come out with a new composition of glass without Al corresponding to x=7.5. In contrast to the above, for Ce-Al(Ga) system, we have observed phase separation in glass after dilute substitution of Ga. It seems that such a phase separation in this system cannot be understood in terms of summation of enthalpy of mixing of the various possible binaries in this system. The substitution of Ga in different valence states might have created chemical pressure leading to creation of two types of distinct major clusters. The phase separation may be due to this. This has also given rise to excursion of Ce 4f-states of the alloy. This and aforesaid ‘chemical pressure’ will be corroborated based on results of binary Ce-Al system under pressure by other investigators.
Aberrant gene expression occurs in parthenogenetic embryos due to abnormal epigenetic modifications in the genome that probably diminish viability and enhance developmental abnormalities in these embryos. In the present study, five developmentally important genes (HPRT1, Cx43, Sox2, Mest and IGF2R) were analysed at different stages in parthenotes (haploid and diploid) and compared with similar stages in in vitro fertilized (IVF) embryos. The results indicated that in haploid parthenotes expression of HPRT1 was upregulated (P < 0.05) only at the 2–4-cell stage whereas Cx43 expression was significantly (P < 0.05) downregulated in all stages as compared with the control. However, expression of this gene was upregulated (P < 0.05) in 2–4-cell and morula stages of diploid parthenotes. Expression of Sox2 was significantly (P < 0.05) downregulated in morula stage haploid parthenotes, whereas it was upregulated (P < 0.05) in 8–16-cell stage diploid embryos. The expression of Mest was upregulated (P < 0.05) at the 2–4-cell stage of both haploid and diploid parthenotes, whereas it was downregulated in 8–16-cell stage diploid embryos as compared with control. IGF2R expression was upregulated (P < 0.05) only in morula stage haploid and diploid parthenote as compared with control. These results indicate that parthenogenetic embryos showed aberrant gene expression of developmentally important genes such as HPRT1, Cx43, Sox2, Mest and IGF2R in comparison with IVF embryos, this finding may be one of the major reasons for the poor developmental competence of parthenogenetic embryos.
Using fast imaging technique, the effect of transverse magnetic field on the shape and dynamics of the lithium plasma plume has been studied. Enhancement in the overall emission intensity as well as appearance of distinct structures (lobes) in the plasma plume in the presence of magnetic field has been observed. By introducing a variable magnetic field, the influence of J × B force in expanding plasma plume across the transverse magnetic field has been explored. It appears that J × B force does not has a substantial role in the observed structures in the present case rather different atomic processes, which get affected due to change in plasma parameters, are responsible for appearance of these structures.
We evaluated the status of tigers Panthera tigris and their prey in Panna Tiger Reserve using occupancy surveys, camera-trap mark-recapture population estimation, and distance sampling along foot transects, in 2006. Forest Range tiger occupancy in the Panna landscape (3,500 km2) estimated by 1,077 surveys of 5 km each was 29% ± SE 1. Within occupied Ranges of the Reserve a mean of 68% ± SE 7 of forest Beats had tiger signs. A total of 800 camera-trap nights yielded 24 captures of seven individual adult tigers within an effective trap area of 185.0 ± SE 15.8 km-2. The best model incorporating individual heterogeneity (Mh) estimated the tiger population to be 9 ± SE 2. Tiger density was 4.9 ± SE 1.5 per 100 km2 and was lower than that reported in 2002 (6.49 tigers per 100 km2). Both occupancy and density indicated a decline of the tiger population in the Reserve. Mean ungulate density was 42.4 ± SE 8.4 km-2 and comparable to other tiger reserves. Since our survey in 2006 tiger status in Panna has deteriorated further because of poaching. Panna was occupied by dacoits in late 2006 and anti-insurgent activities caused further disturbances. In late 2008 there was a single male tiger left in Panna but he has not been seen since January 2009. The Madhya Pradesh Forest department has reintroduced three tigers to Panna from neighbouring tiger reserves. Panna, along with Sariska Tiger Reserve, exemplifies the vulnerability of small, isolated tiger populations to local extinctions caused by poaching, even in areas with suitable habitat and sufficient prey.
Effect of intensity profile of the ablating laser on the dynamics of laser-blow-off (LBO) plume has been studied by fast imaging technique. This work emphasizes the geometrical aspect of the LBO plume, which is an important parameter for various applications. Visualization of the expanding plume reveals that geometrical shape and directionality (divergence) of the plume are highly dependent on the laser intensity profile. Present results demonstrate that the Gaussian profile laser produces a well-collimated, low divergence plasma plume as compared to the plume formed by a top-hat profile laser. The sequence of film removal processes is invoked to explain the role of energy density profile of the ablating laser in LBO mechanism.
The effect of a variable magnetic field on Li plasma produced by laser-blow-off technique has been studied experimentally. Enhancement in the intensity of the spectral lines from neutrals was observed, which varied with the magnetic field. The enhancement in emission from Li I was found to differ for the two different transitions viz. 670.8 nm (2s 2S1/2 ← 2p 2P3/2,1/2) and 610.3 nm (2p 2P1/2,3/2 ← 3d 2P3/2,5/2), which is more prominent for 670.8 nm. Conventionally, the enhancement in emission in the presence of the magnetic field has been explained in terms of radiative recombination. However, the atomic analysis by computing photon emissivity coefficients in the present case has revealed for the first time that it is due to electron impact excitation.
In vitro trials investigating the effects of albendazole and triclabendazole anthelmintics on the growth profiles of the egg-parasitic fungi Paecilomyces lilacinus and Verticillium chlamydosporium were undertaken. In addition, in vivo trials were conducted in goats fed on millet grain cultures of each fungus and administered albendazole and triclabendazole anthelmintics. In vitro growth revealed V. chlamydosporium to be more sensitive to albendazole compared to P. lilacinus. In contrast, triclabendazole had the least inhibitory effect on in vitro growth of both P. lilacinus and V. chlamydosporium. Similar to albendazole, growth of P. lilacinus was more vigorous at 0.5 ppm concentration of triclabendazole. Efforts to re-isolate these egg-parasitic fungi from faeces of goats fed on fungal millet grain cultures before and following single intraruminal administration of albendazole and triclabendazole showed that P. lilacinus was not able to be re-isolated from the faeces at any sampling period. In contrast, V. chlamydosporium was able to be re-isolated from the faeces at all of the sampling periods except for the samples taken at 8–18 h and 18–24 h after administration of albendazole and triclabendazole, respectively. Lack of fungal activity at these times coincided with peak plasma availability of anthelmintics and suggests faecal levels of drugs were also high at these times and impacted negatively on fungal viability.
In this paper, we have constructed some cosmological models which satisfy the present day observational data and the
initial conditions as proposed by Sivaram et al. (Brans & Dicke
1961) with additional requirements
G ∝ tn & Λ∝ tn, Gρ/Λ as a constant along with study of big-rip scenerio.
An amorphous carbon coating, approximately 1.7 μm thick, deposited onto a ductile steel substrate, was indented using a 5-μm radius spherical-tipped diamond indenter to a maximum load of 150 mN. Displacement discontinuities were observed during loading, indicative of crack formation in the system. After indentation, a focused ion beam instrument was used to prepare cross-sections, which revealed the presence of ring, radial, and lateral cracks. A three-dimensional reconstruction of the deformation zone beneath the indent was conducted using a dual ion/electron beam instrument, assisted by a commercial three-dimensional visualization software package. These three-dimensional images enabled a detailed analysis of indentation-induced cracking in this film at submicron resolution. In contrast to traditional understanding and modeling, it was observed that the development of ring cracks was asymmetric for this type of coating/substrate system. Based on this observation, it can be deduced that the strain energy release rate was different for the growth of the spiral ring crack compared with the traditional concentric-ring model. Consequently, the concentric ring-crack fracture model may not be appropriate for the evaluation of the fracture toughness of this type of coating. Hence, three-dimensional images have presented a requirement that the asymmetrical nature of ring and radial cracks should be addressed and carefully considered in the fracture mechanics analysis of this type of hard coating system.
This study was undertaken in order to characterize the Ponwar breed and to establish its present status so that suitable breeding strategies and conservation models could be suggested for the overall improvement of the breed.
The Ponwar is a draught cattle breed and is native to the Pilibhit District of Uttar Pradesh. The breeding tract lies between latitude 28°4' and 28°8' North and between longitude 79°0' and 80°4' East. The coat colour of these animals is brown or black with white patches in varying proportions. The tail switch is white in black animals and black in those having a greater proportion of white patches. The body is small, compact and non-fleshy, the face is small and narrow and the ears are small. The horns are small to medium and curve inward with pointed tips. The hump is small in females and developed in males. The tail is long and reaches to below the hock. Cows have small udders and teats. The animals of this breed possess an aggressive temperament.
The milk production of the Ponwar cows is low, i.e. about 0.5 to 2.5 kg per day for a lactation period of 8 to 10 (average 8.9±0.1) months. Lactation milk yield averaged 462.5±12.1 kg. The age at first calving ranged from 40 to 60 months and the inter-calving period averaged 12.6±0.1 months. The service period in Ponwar cattle varied from 60 to 100 days. The cows remained dry for average of 110.0±2.6 days. Bullocks of this breed can transport an 800 to 1 000 kg load up to 10 kilometres easily. They can plough 0.4 hectares of land in a day working for 6 to 8 hours. Body length, height at wither and heart girth in adult cows averaged 97.1±0.5, 109.0±0.4 and 140.6±0.5 cm, respectively. The animals recorded in the different villages had similar average body measurements corresponding to their category. The survey revealed that about 21% of total cattle population was of Ponwar breed in Puranpur Tehsil. The approximate Ponwar population in the entire breeding tract was estimated as 10 667.
The reduction in cathodoluminescent (CL) degradation of ZnS:Ag phosphor particles coated with aluminum doped zinc oxide (ZAO) films has been investigated. The films were deposited under various oxygen pressures using the atomic flux coating process. The characteristics of the coated phosphor particles with respect to as-received ones were investigated by x-ray photoelectron spectroscopy, CL degradation and scanning electron microscopy. All coated phosphor particles exhibited less CL degradation than the uncoated particles. The coatings deposited under 1.6×10-4 Torr of oxygen, a pressure much lower than the optimum one required to obtain highly transparent and conductive ZnO:Al films, provided the longest brightness lifetime. This increased phosphors lifetime was attributed to the high reactivity of the oxygen deficient ZAO coatings which acted as a sacrificial layer and trapped reactive species before they can reach the phosphor particles and alter their chemical composition.
ZnO films were deposited by Pulsed Laser Deposition (PLD) onto silicon substrates to serve as a buffer layer for GaN films grown by MOCVD. A ZnO buffer layer was found to improve the quality of GaN grown on Si. The thermal stability of ZnO as a buffer layer was also examined. It was determined that exposure of ZnO/Si to NH3 at high temperature (> 600°C) results in the decomposition of ZnO and subsequent poor nucleation of GaN. The ZnO layer thickness on GaN quality was found to be important.
Interest in rare earth-activated oxide-based phosphor thin films for high-resolution display devices has been growing in the last few decades. However, thin-film phosphors typically have a significantly reduced brightness compared to equivalent powder phosphor materials. Several possible explanations have been suggested for the lower brightness including internal reflection and the small interaction volume between the incident beam and the solid. In this report, we show another factor to be crucial to external radiative efficiency, the porosity of the films. Porosity creates internal surfaces that act as a "dead layer" which decreases the emission efficiency. Using Z-contrast imaging in the scanning transmission electron microscope (STEM) with simultaneous cathodoluminescence (CL) imaging, the dead layer is directly observed, and quantitative accounts for the reduction of luminescent efficiency.
Eu activated Y2O3 thin films with thickness of about 200 nm were deposited on (001) LaAlO3 substrates by laser ablation. TEM analysis of the samples was conducted in a Philips EM-400 electron microscope operated at l00kV.
There has been intense interest in preparing single crystalline yttrium oxide (Y2O3) thin films for applications in ultra-large scale integration (ULSI) gate insulators, ULSI capacitors, and, by addition of suitable dopant species, for electroluminescent devices. Y2O3 has a C-type rare-earth sesquioxide structure, closely related to the fluorite structure with a cell parameter a= 1.060 nm and space group Th (Ia3). LaAIO3 (LAO) is a rhombohedral structure with lattice parameters a = 0.378 nm, θ ≤ 90.5°. The lattice mismatch with the <110> direction of the YO is therefore less than 0.8%, and so we would anticipate epitaxial growth of single crystalline YO thin films on the LAO (001) substrate to be feasible. Eu activated YO thin films were deposited by laser ablation on (001) LAO substrates. TEM bright field images and electron diffraction patterns were recorded in a Philips EM-400 electron microscope operated at lOOkV. Z-contrast imaging was conducted in a VG HB603 STEM at 300kV. In this presentation, we will report the epitaxial growth of YO thin films doped with ∼ wt 4% Eu on a LaAlO3 substrate, and the atomic structure of the interface.
Mehsana buffalo is distributed in Mehsana, Banaskantha and Sabarkantha districts of North Gujarat in India. The animals are reared for milk production. The management practices in the breeding tract were studied. The physical, production and reproductive characters were recorded. The Dudhsagar Research and Development Association located in Mehsana district has undertaken breed improvement programmes in farmers'herds by running field progeny testing and providing other animal husbandry services like artificial insemination, health coverage, etc. This has resultedin the improvement in the reproductive performance as is evident from the decreasein the average first service period by 74 days and the average first calving interval by 103 days from 1989 to 1997. Microsatellite DNA marker analysis was carried out on 25 Mehsana buffalo DNA samples using seven markers for genetic characterization of the breed. Number of alleles at different loci ranged from four to seven and heterozygosity ranged from 0.40 to 0.92.
The characteristics of indium tin oxide (ITO) films grown at room temperature on (100) Si and Corning glass substrates by an in situ ultraviolet-assisted pulsed laser deposition (UVPLD) technique have been investigated. The most important parameter, which influenced the optical and electrical properties of the grown films, was the oxygen pressure. For oxygen pressure below 1 mtorr, films were metallic, with very low optical transmittance and rather high resistivity values. The resistivity value decreased when using higher oxygen pressures while the optical transmittance increased. The optimum oxygen pressure was found to be around 10 mtorr. For higher oxygen pressures, the optical transmittance was better but a rapid degradation of the electrical conductivity was noticed. X-ray photoelectron spectroscopy investigations showed that ITO films grown at 10 mtorr oxygen are fully oxidized. All of the grown films were amorphous regardless of the oxygen pressure used.
The properties of thin oxide films such as Y2O3, ZnO and Ba0.5Sr0.5TiO3 grown using an in situ ultraviolet (UV)-assisted pulsed laser deposition (UVPLD) technique have been studied. With respect to films grown by conventional PLD under similar conditions but without UV illumination, the UVPLD grown films exhibited better structural and optical and electrical properties, especially for lower substrate temperatures. They also exhibited a better stoichiometry and contained less physisorbed oxygen than the conventional PLD grown layers. These improvements can be traced to several factors. Firstly, deep UV photons and ozone ensure a better in situ cleaning of the substrate prior to the deposition. Secondly, the presence of more reactive gaseous species like ozone and atomic oxygen formed by photodissociation of molecular O2 promotes the growth of more oxygenated films. Thirdly, absorption of UV photons by adatoms could result in an increased of their surface mobility. All these factors have a beneficial effect upon crystalline growth, especially for moderate substrate temperatures. For optimised growth conditions, the crystalline quality and properties of ultraviolet-assisted pulsed laser deposited films was similar to that of films grown using conventional PLD at substrate temperatures of at least 200°C higher.