Marginal Strength of Collarless Metal Ceramic Crown

Metal ceramic restorations have been implicated for the discoloration in area of labiogingivalmargin. Attempts to rectify this, by altering the design of metal frameworkswill lead to decrease in fracture strength atmargin. This in vitro study compared the fracture strength at margins of metal ceramic crowns cemented to metal tooth analogs. Crowns evaluated with different marginal configurations, shoulder and shoulder bevel with 0 mm, 0.5 mm, 1 mm, and 1.5 mm, were selected. Methods. Maxillary right canine typhodont tooth was prepared to receive a metal ceramic crown with shoulder margin. This was duplicated to get 20 metal teeth analogs. Then the same tooth was reprepared to get shoulder bevel configuration. These crowns were then cemented onmetal teeth analogs and tested for fracture strength atmargin on an Instron testing machine. A progressive compressive load was applied using 6.3 mm diameter rod with crosshead speed of 2.5 mm per minute. Statisticaly analysis was performed with ANOVA, Student's “t” test and “f” test. Results. The fracture strength of collarless metal ceramic crowns under study exceeded the normal biting force. Therefore it can be suggested that collarless metal ceramic crowns with shoulder or shoulder bevel margins up to 1.5 mm framework reduction may be indicated for anteriormetal ceramic restorations. Significance. k Collarless metal ceramic crowns have proved to be successful for anterior fixed restorations. Hence, it may be subjected to more clinical trials

Rare earth Dy activated Li3PO4:Dy phosphors for lyoluminescence dosimetry of ionizing radiations

     Rare earth Dy doped Li3PO4 phosphate based phosphors were prepared by high temperature solid state diffusion technique. The peak LL intensity initially increases with increasing mass of the sample, then tends to attain a saturation value for higher mass of the solute added to the solvent. Eaelier experiments on gamma irradiated crystals have proved that the light emission originates from the recombination of released F-centres with trapped holes (V2-centres) at the liquid-solid interface.In this paper lyoluminescence(LL) characteristics of Li3PO4:Dy phosphors have been reported . These LL characteristics of Li3PO4 phosphor may be useful for high radiation dosimetry using LL technique

Comparative study on mechanoluminescence of Eu2+ doped phosphate based phosphors.

Eu2+ doped phosphate based phosphors were prepared by solid state diffusion technique. The phosphors have simple glow curve with single peak It is clear that the ML intensity increases with increasing concentration of Eu, attained an optimum value for 1 mole % for Sr5(PO4)3Cl:Eu2+, and 2 mole% for Li3PO4:Eu2+ and LaPO4:Eu2+, then decreases with further increase in concentration of Eu. The trapping and detrapping of charge carriers in the material can be studied using ML. It is believed that in the dynamic process of loading, internal friction originating from defects activates holes released from traps and stimulates mechanoluminescience. This phosphor can be used in the dosimetry of ionizing radiations using mechanoluminescence

Biosand Filter for Removal of Chemical Contaminants From Water

Numerous reports by the United Nations and the World Health Organization have indicated a significant worldwide problem with water pollution and inaccessibility to potable drinking water. Due to technological and economical barriers, the problem with water pollution is particularly more serious for under-developed and developing countries. The present study is aimed at designing, constructing and evaluating a cost-effective biosand filter was undertaken. Results indicated the removal of up to 80% total hardness, 86% chlorides, 96% turbidity and 90% colour. Moreover, the filter's performance was appraised by the absence of E. coli in the filtered sample. The filter describes the proven bioremediation technology and its ability to empower at-risk populations to use naturally occurring biology and readily available materials as a sustainable way to achieve the health benefits of safe drinking water

Assignment of the <i>TYK2</i> gene to equine chromosome 7q12-q13 (Brief report)

Abstract. Tyrosine kinase 2 (TYK2) is a member of the janus kinase gene family and encodes an 1187 amino acid protein. All four members of the janus kinase family JAK1, JAK2, JAK3, and TYK2 associate with various cytokine receptors and mediate the signal transduction by tyrosine phosphorylation of downstream targets (YAMOAKA et al., 2004). Studies with tyk2 deficient mice demonstrated impairment of interferon α/β signaling (KARAGHIOSOFF et al., 2003). Mutations in the murine tyk2 gene are associated with increased susceptibility to infectious and autoimmune diseases (SHAW et al., 2003). The human TYK2 gene consists of 25 exons spanning 30,003 bp on human chromosome 19p13.2 starting at 10,322,209 bp. The objective of this study was to determine the chromosomal location of TYK2 in the horse by FISH and RH mapping. </jats:p

Biosand Filter for Removal of Chemical Contaminants from Water

Numerous reports by the United Nations and the World Health Organization have indicated a significant worldwide problem with water pollution and inaccessibility to potable drinking water. Due to technological and economical barriers, the problem with water pollution is particularly more serious for under-developed and developing countries. The present study is aimed at designing, constructing and evaluating a cost-effective biosand filter was undertaken. Results indicated the removal of up to 80% total hardness, 86% chlorides, 96% turbidity and 90% colour. Moreover, the filter’s performance was appraised by the absence of E. coli in the filtered sample. The filter describes the proven bioremediation technology and its ability to empower at-risk populations to use naturally occurring biology and readily available materials as a sustainable way to achieve the health benefits of safe drinking water

Gajah. Securing the Future for Elephants in India.

It is estimated that six in every ten wild Asian elephants live in India. This report by the Ministry of Environment and Forests in India outlines plans to safeguard the species and associated habitats in the face of rapid economic expansion and development pressures

The Potential Energy Landscape and Mechanisms of Diffusion in Liquids

The mechanism of diffusion in supercooled liquids is investigated from the potential energy landscape point of view, with emphasis on the crossover from high- to low-T dynamics. Molecular dynamics simulations with a time dependent mapping to the associated local mininum or inherent structure (IS) are performed on unit-density Lennard-Jones (LJ). New dynamical quantities introduced include r2_{is}(t), the mean-square displacement (MSD) within a basin of attraction of an IS, R2(t), the MSD of the IS itself, and g_{loc}(t) the mean waiting time in a cooperative region. At intermediate T, r2_{is}(t) posesses an interval of linear t-dependence allowing calculation of an intrabasin diffusion constant D_{is}. Near T_{c} diffusion is intrabasin dominated with D = D_{is}. Below T_{c} the local waiting time tau_{loc} exceeds the time, tau_{pl}, needed for the system to explore the basin, indicating the action of barriers. The distinction between motion among the IS below T_{c} and saddle, or border dynamics above T_{c} is discussed.Comment: submitted to pr

Novel Gene Acquisition on Carnivore Y Chromosomes

Despite its importance in harboring genes critical for spermatogenesis and male-specific functions, the Y chromosome has been largely excluded as a priority in recent mammalian genome sequencing projects. Only the human and chimpanzee Y chromosomes have been well characterized at the sequence level. This is primarily due to the presumed low overall gene content and highly repetitive nature of the Y chromosome and the ensuing difficulties using a shotgun sequence approach for assembly. Here we used direct cDNA selection to isolate and evaluate the extent of novel Y chromosome gene acquisition in the genome of the domestic cat, a species from a different mammalian superorder than human, chimpanzee, and mouse (currently being sequenced). We discovered four novel Y chromosome genes that do not have functional copies in the finished human male-specific region of the Y or on other mammalian Y chromosomes explored thus far. Two genes are derived from putative autosomal progenitors, and the other two have X chromosome homologs from different evolutionary strata. All four genes were shown to be multicopy and expressed predominantly or exclusively in testes, suggesting that their duplication and specialization for testis function were selected for because they enhance spermatogenesis. Two of these genes have testis-expressed, Y-borne copies in the dog genome as well. The absence of the four newly described genes on other characterized mammalian Y chromosomes demonstrates the gene novelty on this chromosome between mammalian orders, suggesting it harbors many lineage-specific genes that may go undetected by traditional comparative genomic approaches. Specific plans to identify the male-specific genes encoded in the Y chromosome of mammals should be a priority