Lattice expansion and non-collinear to collinear ferrimagnetic order in MnCr2_2O4_4 nanoparticle

We report magnetic behaviour of MnCr$_2$O$_4$, which belongs to a special class of spinel, known as chromite. Bulk MnCr$_2$O$_4$ shows a sequence of magnetic states, which follows paramagnetic (PM) to collinear ferrimagnetic (FM) state below T$_C$ $\sim$ 45 K and collinear FM state to non-collinear FM state below T$_S$ $\sim$ 18 K. The non-collinear spin structure has been modified on decreasing the particle size, and magnetic transition at T$_S$ decreases in nanoparticle samples. However, ferrimagnetic order is still dominating in nanoparticles, except the observation of superparamagnetic like blocking and decrease of spontaneous magnetization for nanoparticle. This may, according to the core-shell model of ferrimagnetic nanoparticle, be the surface disorder effect of nanoparticle. The system also show the increase of T$_C$ in nanoparticle samples, which is not consistent with the core-shell model. The analysis of the M(T) data, applying spin wave theory, has shown an unusual Bloch exponent value 3.35 for bulk MnCr$_2$O$_4$, which decreases and approaches to 1.5, a typical value for any standard ferromagnet, with decreasing the particle size. MnCr$_2$O$_4$ has shown a few more unusual behaviour. For example, lattice expansion in nanoparticle samples. The present work demonstrates the correlation between a systematic increase of lattice parameter and the gradual decrease of B site non-collinear spin structure in the light of magnetism of MnCr$_2$O$_4$ nanoparticles

A Systematic Study towards the Synthesis, Isolation, and Recrystallization of Atovaquone, an Antimalarial Drug: A Sustainable Synthetic Pathway

In the present work, studies were conducted towards the synthesis of 2-[trans-4-(4-chlorophenyl) cyclohexyl]-3-hydroxy-1 ,4-naphthoquinone 5 with systematic reaction and recrystallization condition optimization to isolate 5 in high yield with better purity. Synthesis of 5 was done by the hydrolysis of 2-[trans-4-(4-chlorophenyl) cyclohexyl]-3-chloro-1, 4-naphthoquinone 4, which was isolated by the decarboxylative condensation of trans-4-(4-chlorophenyl) cyclohexanecarboxylic acid 3 with naphthoquinone moiety. After the hydrolysis of 4, isolation of crude 5 was done by the use of acetic acid instead of dilute hydrochloric acid, product 5 was isolated in good purity with very less polar impurities. The study extends to provide the polymorphic form I of 5 by the useof solvent combination for the recrystallization, prior artreports the use of a large volume of solvent for theisolation of polymorphic form I of 5. The use of a largevolume of solvent becomes a bottleneck for thecommercial synthesis of 5

Molecular identification and genetic diversity analysis of sugarcane clones by SSR markers

Sugarcane is one of the important crops with high heterozygosity and phenotypic polymorphism. Varietal identification and characterization is one of the important aspects in any breeding programme. Forty sugarcane clones from Pre -zonal varietal trial (PZVT) conducted at Ugar, North Karnataka were characterized through Simple sequence repeats (SSR) markers using a set of 15 sugarcane specific primer pairs which amplified a total of 164 alleles with an average of 10.93 alleles per pair. Primer NKS 33 was highly polymorphic and produced more than 15 polymorphic alleles and was unique in all the clones studied. Six primers i.e., NKS 2, NKS 6, NKS 7, NKS 40, NKS 42 and NKS 11 were moderately polymorphic by producing 10 to 13 alleles. Percentage of polymorphic bands ranged from 75.0 % (NKS 3) to 100.0 % (NKS 40 and NKS 42). Primers viz., SMC 1039 GC, mSSCIR 54, NKS 2, NKS 7, NKS 9, NKS 33, NKS 40, NKS 42 and NKS 11 were highly informative and generated above 85.0 % of polymorphic bands. Among the primers used, SMC 1039 GC, NKS 33, NKS 42 and NKS 43 produced the maximum number of unique markers in different clones and hence the combined application of these primers will be useful in unambiguous varietal identification. The cluster analysis based on the genetic similarity matrix grouped the 40 clones into two major clusters CI and CII. The largest cluster CII contained the maximum of 38 clones. Cluster C II was further sub-grouped into IIa, IIb, IIc and IId and each sub-cluster comprised 7, 11, 6 and 14 clones respectively. The unique DNA markers and the genetically diverse combinations identified in the present study will enhance the exploitation of genetic diversity present in the clones in breeding programmes and promising twenty eight entries for yield and quality

InCoB2010 - 9thInternational Conference on Bioinformatics at Tokyo, Japan, September 26-28, 2010

10.1186/1471-2105-11-S7-S1BMC Bioinformatics11SUPPL. 7-BBMI

Magnetic enhancement of Co0.2_{0.2}Zn0.8_{0.8}Fe2_2O4_4 spinel oxide by mechanical milling

We report the magnetic properties of mechanically milled Co$_{0.2}$Zn$_{0.8}$Fe$_2$O$_4$ spinel oxide. After 24 hours milling of the bulk sample, the XRD spectra show nanostructure with average particle size $\approx$ 20 nm. The as milled sample shows an enhancement in magnetization and ordering temperature compared to the bulk sample. If the as milled sample is annealed at different temperatures for the same duration, recrystallization process occurs and approaches to the bulk structure on increasing the annealing temperatures. The magnetization of the annealed samples first increases and then decreases. At higher annealing temperature ($\sim$ 1000$^{0}$C) the system shows two coexisting magnetic phases {\it i.e.}, spin glass state and ferrimagnetic state, similar to the as prepared bulk sample. The room temperature M\"{o}ssbauer spectra of the as milled sample, annealed at 300$^{0}$C for different durations (upto 575 hours), suggest that the observed change in magnetic behaviour is strongly related with cations redistribution between tetrahedral (A) and octahedral (O) sites in the spinel structure. Apart from the cation redistribution, we suggest that the enhancement of magnetization and ordering temperature is related with the reduction of B site spin canting and increase of strain induced anisotropic energy during mechanical milling.Comment: 14 pages LaTeX, 10 ps figure

Global injury morbidity and mortality from 1990 to 2017 : results from the Global Burden of Disease Study 2017

Correction:Background Past research in population health trends has shown that injuries form a substantial burden of population health loss. Regular updates to injury burden assessments are critical. We report Global Burden of Disease (GBD) 2017 Study estimates on morbidity and mortality for all injuries. Methods We reviewed results for injuries from the GBD 2017 study. GBD 2017 measured injury-specific mortality and years of life lost (YLLs) using the Cause of Death Ensemble model. To measure non-fatal injuries, GBD 2017 modelled injury-specific incidence and converted this to prevalence and years lived with disability (YLDs). YLLs and YLDs were summed to calculate disability-adjusted life years (DALYs). Findings In 1990, there were 4 260 493 (4 085 700 to 4 396 138) injury deaths, which increased to 4 484 722 (4 332 010 to 4 585 554) deaths in 2017, while age-standardised mortality decreased from 1079 (1073 to 1086) to 738 (730 to 745) per 100 000. In 1990, there were 354 064 302 (95% uncertainty interval: 338 174 876 to 371 610 802) new cases of injury globally, which increased to 520 710 288 (493 430 247 to 547 988 635) new cases in 2017. During this time, age-standardised incidence decreased non-significantly from 6824 (6534 to 7147) to 6763 (6412 to 7118) per 100 000. Between 1990 and 2017, age-standardised DALYs decreased from 4947 (4655 to 5233) per 100 000 to 3267 (3058 to 3505). Interpretation Injuries are an important cause of health loss globally, though mortality has declined between 1990 and 2017. Future research in injury burden should focus on prevention in high-burden populations, improving data collection and ensuring access to medical care.Peer reviewe

Development and characterization of deep reactive ion etching technology for through silicon interconnection

Deep reactive ion etching (DRIE) is an enabling technology for three dimensional (3D) integration of planar integrated circuits. This work focuses on various challenges associated with deep reactive ion etching technology for realizing through silicon interconnection for 3D Microsystems application. In the first part of the thesis, stress simulation studies were done on TSV structures of various via geometries and shapes to determine the regions of high stress due to CTE mismatch. It was determined that the top and bottom of the vias and the surrounding materials experience maximum mechanical stress. It was also found that the stress is concentrated in the sharp peaks and valleys of the scallops formed by Bosch etch process. A test vehicle was designed and fabricated by copper damascene process with various geometries and barrier structures to experimentally study the effect of sidewall scallops on electrical leakage between adjacent TSV structures. It was shown that the leakage current can be reduced by about nearly 3 orders of magnitude when the sidewall roughness is reduced or replaced by a smoother sidewall for the initial few microns of the depth of the via by using a non-Bosch etch process. This study has shown that the Bosch etch process can still be used, with all its merits of high etch rate and high etch selectivity, for vertical TSV etch application by tailoring a short first etch step with smooth sidewall.DOCTOR OF PHILOSOPHY (EEE

Multiterminal Net Routing For Partial Crossbar-Based Multi-Fpga Systems

Multi-FPGA (field-programmable gate arrays) systems are used as custom computing machines to solve compute-intensive problems and also in the verification and prototyping of large circuits. In this paper, we address the problem of routing multiterminal nets in a multi-FPGA system that uses partial crossbars as interconnect structures. First, we model the multiterminal routing problem as a partitioned bin-packing problem and formulate it as an integer linear programming problem where the number of variables is exponential. A fast heuristic is applied to compute an upper bound on the routing solution. Then, a column generation technique is used to solve the linear relaxation of the initial master problem in order to obtain a lower bound on the routing solution. This is followed by an iterative branch-and-price procedure that attempts to find a routing solution somewhere between the two established bounds. In this regard, the proposed algorithm guarantees an exact-routing solution by searching a branch-and-price tree. Due to the tightness of the bounds, the branch-and-price tree is small resulting in shorter execution times. Experimental results are provided for different netlists and board configurations in order to demonstrate the algorithms performance. The obtained results show that the algorithm finds an exact routing solution in a very short time