369 research outputs found
Probabilistic Neural Network based Approach for Handwritten Character Recognition
In this paper, recognition system for totally unconstrained handwritten characters for south Indian language of Kannada is proposed. The proposed feature extraction technique is based on Fourier Transform and well known Principal Component Analysis (PCA). The system trains the appropriate frequency band images followed by PCA feature extraction scheme. For subsequent classification technique, Probabilistic Neural Network (PNN) is used. The proposed system is tested on large database containing Kannada characters and also tested on standard COIL-20 object database and the results were found to be better compared to standard techniques
Understanding the excess COVID-19 burden among immigrants in Norway
Background: We aim to use intermarriage as a measure to disentangle the role of exposure to virus, susceptibility and care in differences in burden of COVID-19, by comparing rates of COVID-19 infections between immigrants married to a native and to another immigrant. Methods: Using data from the Norwegian emergency preparedness, register participants (N=2 312 836) were linked with their registered partner and categorized based on own and partner's country of birth. From logistic regressions, odds ratios (OR) of COVID-19 infection (15 June 2020-01 June 2021) and related hospitalization were calculated adjusted for age, sex, municipality, medical risk, occupation, household income, education and crowded housing. Results: Immigrants were at increased risk of COVID-19 and related hospitalization regardless of their partners being immigrant or not, but immigrants married to a Norwegian-born had lower risk than other immigrants. Compared with intramarried Norwegian-born, odds of COVID-19 infection was higher among persons in couples with one Norwegian-born and one immigrant from Europe/USA/Canada/Oceania (OR 1.42-1.46) or Africa/Asia/Latin-America (OR 1.91-2.01). Odds of infection among intramarried immigrants from Africa/Asia/Latin-America was 4.92. For hospitalization, the corresponding odds were slightly higher. Conclusion: Our study suggests that the excess burden of COVID-19 among immigrants is explained by differences in exposure and care rather than susceptibility. Keywords: COVID-19; Norway; hospitalization; immigrant; infection; register data.Understanding the excess COVID-19 burden among immigrants in NorwaypublishedVersio
Citotoksičnost, inhibicija agregacije trombocita i antioksidativna aktivnost ekstrakata biljke Curcuma amada Roxb.
Mango ginger (Curcuma amada Roxb.) is a unique spice having morphological resemblance to ginger but imparts raw mango flavour. The sequential extraction of mango ginger rhizome powder was carried out using hexane, chloroform, ethyl acetate, acetone, methanol and water. The phenolic content was the highest in methanol extract, followed by acetone, ethyl acetate and water extracts. Among these, chloroform extract exhibited high lipid peroxidation inhibitory activity and metal chelating activity, whereas ethyl acetate extract showed high DPPH radical scavenging activity and superoxide radical scavenging activity. Mango ginger extracts also showed potential platelet aggregation inhibitory activity and cytotoxicity properties.Curcuma amada Roxb. jedinstveni je začin jer morfološki nalikuje đumbiru, a po okusu je sličan mangu. Provedena je sekvencijska ekstrakcija praha dobivenog od rizoma te biljke pomoću heksana, kloroforma, etilnog acetata, acetona, metanola i vode. Udjel fenola bio je najveći u ekstraktu dobivenom pomoću metanola, zatim acetona i etilnog acetata, a najmanji u vodenom ekstraktu. Ekstrakt dobiven pomoću kloroforma imao je najveću sposobnost inhibicije peroksidacije lipida i keliranja metala, a onaj dobiven pomoću etilnog acetata najbolje svojstvo uklanjanja DPPH i superoksidnih radikala. Ekstrakti biljke Curcuma amada Roxb. imali su i sposobnost inhibicije agregacije trombocita te citotoksična svojstva
Oxidative DNA cleavage, cytotoxicity and antimicrobial studies of l-ornithine copper (II) complexes
New ternary copper (II) complexes, Cu(l-orn)(B)(Cl)(Cl·2H 2O) (1-2) where l-orn is l-ornithine, B is an N,N-donor heterocyclic base, viz. 2,2â²-bipyridine (bpy, 1) and 1,10-phenanthroline (phen, 2), were synthesized and characterized by various spectroscopic techniques. Complex 2 is characterized by the X-ray single crystallographic method. The complex shows a distorted square-pyramidal (4 + 1) CuN 3OCl coordination sphere. Binding interactions of the complexes with calf thymus DNA (CT-DNA) were investigated by UV-Vis absorption titration, ethidium bromide displacement assay, viscometric titration experiment and DNA melting studies. Complex 2 shows appreciable chemical nuclease activity in the presence of 3-mercaptopropionic acid (MPA). The complexes were subjected to in vitro cytotoxicity studies against carcinomic human alveolar basal epithelial cells (A-549) and human epithelial (HEp-2) cells. The IC 50 values of 1 and 2 are less than that of cisplatin against HEp-2 cell lines. MIC values for 1 against the bacterial strains Streptococcus mutans and Pseudomonas aeruginosa are 0.5 mM. © 2012 Elsevier Ltd. All rights reserved
Genetic diversity and differentiation within and between cultivated (Vitis vinifera L. ssp. sativa) and wild (Vitis vinifera L. ssp. sylvestris) grapes
Genetic characterization of 502 diverse grape accessions including 342 cultivated (V. vinifera ssp. sativa) and 160 wild (V. vinifera ssp. sylvestris) grapes showed considerable genetic diversity among accessions. A total of 117 alleles were detected across eight SSR loci with the average of 14 alleles per locus. The genetic diversity of wild grapes was slightly lower than that observed in the cultivated grapes probably due to small populations and severe natural selection leading to drift and loss of alleles and heterozygosity in wild grapes. The distance cluster analysis (CA) supported the classical ecogeographic groups with moderate genetic differentiation among them. There was a greater affinity of Occidentalis grape to wild grape from the Caucasus than other groups. However, a number of low to moderate frequency alleles that are present in the cultivated grape are not represented in the wild grape.
A Mouse Keratin 1 Mutation Causes Dark Skin and Epidermolytic Hyperkeratosis
Chemical mutagenesis in the mouse has increased the utility of phenotype-driven genetics as a means for studying different organ systems, developmental pathways, and pathologic processes. From a large-scale screen for dominant phenotypes in mice, a novel class of pigmentation mutants was identified by dark skin (Dsk). We describe a Dsk mutant, Dsk12, which models the human disease, epidermolytic hyperkeratosis (EHK). At 2 days of age, mutant animals exhibit intraepidermal blisters and erosions at sites of trauma, and by 2 weeks of age develop significant hyperkeratosis. We identified a missense mutation in mutant animals that predicts an S194P amino acid substitution in the 1A domain of Keratin 1, a known target for human mutations that cause EHK. Dsk12 recapitulates the gross pathologic, histologic, and genetic aspects of the human disorder, EHK
Fabrication, Mechanical and Wear Properties of Aluminum (Al6061)-Silicon Carbide-Graphite Hybrid Metal Matrix Composites
In recent times, the use of aluminum alloy-based Hybrid Metal Matrix Composites (HMMCs) is being increased in aerospace and automotive applications. HMMCs compensate for the low desirable properties of each filler used. However, the mechanical properties of HMMCs are not well understood. In particular, microstructural investigations and wear optimization studies of HMMCs are not clear. Therefore, further studies are required. The present study is aimed at fabricating and mechanical and wear characterizing and microstructure investigating of Silicon Carbide (SiC) and Graphite (Gr) added in Aluminum (Al) alloy Al6061 HMMCs. The addition of SiC particles was in the range from 0 to 9 weight percentage (wt.%) in steps of 3, along with the addition of 1 wt.% Gr in powder form. The presence of alloying elements in the Al6061 alloy was identified using the Energy Dispersive X-Ray Analysis (EDX). The dispersion of SiC and Gr particles in the alloy was investigated using metallurgical microscope and Scanning Electron Microscopy (SEM). The gain in strength can be attributed to the growth in dislocation density. The nature of fracture was quasi-cleavage. The microstructure examination reveals the uniform dispersion of the reinforcement. Density, hardness, and Ultimate Tensile Strength values observed to be increased with increased contents of SiC reinforcement. Besides, wear studies were performed in dry sliding conditions. Optimization studies were performed to investigate the effect of parameters that affecting the wear. The sliding wear resistance was noticed to be improved concerning higher amounts of reinforcement leading to a decrease in delamination and adhesive wear. The predicted values for the wear rate have also been compared with the experimental results and good correlation is obtained
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Patterns of genomic and phenomic diversity in wine and table grapes.
Grapes are one of the most economically and culturally important crops worldwide, and they have been bred for both winemaking and fresh consumption. Here we evaluate patterns of diversity across 33 phenotypes collected over a 17-year period from 580 table and wine grape accessions that belong to one of the world's largest grape gene banks, the grape germplasm collection of the United States Department of Agriculture. We find that phenological events throughout the growing season are correlated, and quantify the marked difference in size between table and wine grapes. By pairing publicly available historical phenotype data with genome-wide polymorphism data, we identify large effect loci controlling traits that have been targeted during domestication and breeding, including hermaphroditism, lighter skin pigmentation and muscat aroma. Breeding for larger berries in table grapes was traditionally concentrated in geographic regions where Islam predominates and alcohol was prohibited, whereas wine grapes retained the ancestral smaller size that is more desirable for winemaking in predominantly Christian regions. We uncover a novel locus with a suggestive association with berry size that harbors a signature of positive selection for larger berries. Our results suggest that religious rules concerning alcohol consumption have had a marked impact on patterns of phenomic and genomic diversity in grapes
Genetic structure and domestication history of the grape
The grape is one of the earliest domesticated fruit crops and, since antiquity, it has been widely cultivated and prized for its fruit and wine. Here, we characterize genome-wide patterns of genetic variation in over 1,000 samples of the domesticated grape, Vitis vinifera subsp. vinifera, and its wild relative, V. vinifera subsp. sylvestris from the US Department of Agriculture grape germ-plasm collection. We find support for a Near East origin of vinifera and present evidence of introgression from local sylvestris as the grape moved into Europe. High levels of genetic diversity and rapid linkage disequilibrium (LD) decay have been maintained in vinifera, which is consistent with a weak domestication bottleneck followed by thousands of years of widespread vegetative propagation. The considerable genetic diversity within vinifera, however, is contained within a complex network of close pedigree relationships that has been generated by crosses among elite cultivars. We show that first-degree relationships are rare between wine and table grapes and among grapes from geographically distant regions. Our results suggest that although substantial genetic diversity has been maintained in the grape subsequent to domestication, there has been a limited exploration of this diversity. We propose that the adoption of vegetative propagation was a double-edged sword: Although it provided a benefit by ensuring true breeding cultivars, it also discouraged the generation of unique cultivars through crosses. The grape currently faces severe pathogen pressures, and the long-term sustainability of the grape and wine industries will rely on the exploitation of the grape's tremendous natural genetic diversity
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