501 research outputs found

    Poly(styrene-co-vinylbenzylchloride-co-divinylbenzene) coated iron oxide: Synthesis and effects on size and morphology

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    Iron oxide nanoparticles were coated with a polymer synthesized from the monomers of styrene, divinylbenzene, and vinylbenzylchloride. The resultant polymer microspheres from synthesis without nanoparticle loading are primarily monodispersed with a diameter of 3.45 μm as measured by scanning electron microscopy. The addition of 1% nanoparticles by mass appears to decrease the size of the microspheres down to 2.04 μm as well as increase the polydispersity. This trend is also seen to continue as you add more nanoparticles to the system going from 3.45 μm with 0% nanoparticles down to below 1 μm for 5% nanoparticles. This indicates that the particles are not just incorporated into the polymer matrix but act as nucleation sites to begin the polymerization process. The polymerization process was found to have no effect on the nanoparticles themselves as the magnetic characterization showed only a mass dilution in saturation when corrected by thermal gravimetric analysis

    Applications of Direct Injection Soft Chemical Ionisation-Mass Spectrometry for the Detection of Pre-blast Smokeless Powder Organic Additives

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    Analysis of smokeless powders is of interest from forensics and security perspectives. This article reports the detection of smokeless powder organic additives (in their pre-detonation condition), namely the stabiliser diphenylamine and its derivatives 2-nitrodiphenylamine and 4-nitrodiphenylamine, and the additives (used both as stabilisers and plasticisers) methyl centralite and ethyl centralite, by means of swab sampling followed by thermal desorption and direct injection soft chemical ionisation-mass spectrometry. Investigations on the product ions resulting from the reactions of the reagent ions H3O+ and O2+ with additives as a function of reduced electric field are reported. The method was comprehensively evaluated in terms of linearity, sensitivity and precision. For H3O+, the limits of detection (LoD) are in the range of 41-88 pg of additive, for which the accuracy varied between 1.5 and 3.2%, precision varied between 3.7 and 7.3% and linearity showed R20.9991. For O2+, LoD are in the range of 72 to 1.4 ng, with an accuracy of between 2.8 and 4.9% and a precision between 4.5 and 8.6% and R20.9914. The validated methodology was applied to the analysis of commercial pre-blast gun powders from different manufacturers.(VLID)4826148Accepted versio

    CONSIDERATIONS ON THE TECHNOLOGIES FOR SEPARATING FRUIT SEEDS WITH APPLICATIONS ON THE SEPARATION OF SEABUCKTHORN PULP FROM SEEDS

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    Sea-buckthorn is a shrub fruit whose benefits have been known since antiquity. The whole plant is considered medicinal by specialists in the field, but the most active part is the sea-buckthorn fruit because it has a beneficial effect on the entire human body and more recently on animal breeding. A high-value by-product is sea-buckthorn oil, which is currently gaining traders’ attention at international level and which is obtained from both fruit and pomace resulting from the extraction of juice (shells and seeds). This paper presents some representative technolo-gies and installations used for fruit processing in general, technologies that will be the basis for the realization by INMA Bucharest of a technical equipment for separating sea-buckthorn pulp from the seeds

    Identification of Rare Causal Variants in Sequence-Based Studies: Methods and Applications to VPS13B, a Gene Involved in Cohen Syndrome and Autism

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    Pinpointing the small number of causal variants among the abundant naturally occurring genetic variation is a difficult challenge, but a crucial one for understanding precise molecular mechanisms of disease and follow-up functional studies. We propose and investigate two complementary statistical approaches for identification of rare causal variants in sequencing studies: a backward elimination procedure based on groupwise association tests, and a hierarchical approach that can integrate sequencing data with diverse functional and evolutionary conservation annotations for individual variants. Using simulations, we show that incorporation of multiple bioinformatic predictors of deleteriousness, such as PolyPhen-2, SIFT and GERP++ scores, can improve the power to discover truly causal variants. As proof of principle, we apply the proposed methods to VPS13B, a gene mutated in the rare neurodevelopmental disorder called Cohen syndrome, and recently reported with recessive variants in autism. We identify a small set of promising candidates for causal variants, including two loss-of-function variants and a rare, homozygous probably-damaging variant that could contribute to autism risk

    Quantifying Missing Heritability at Known GWAS Loci

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    Recent work has shown that much of the missing heritability of complex traits can be resolved by estimates of heritability explained by all genotyped SNPs. However, it is currently unknown how much heritability is missing due to poor tagging or additional causal variants at known GWAS loci. Here, we use variance components to quantify the heritability explained by all SNPs at known GWAS loci in nine diseases from WTCCC1 and WTCCC2. After accounting for expectation, we observed all SNPs at known GWAS loci to explain 1.29 X more heritability than GWAS-associated SNPs on average (P = 3.3 X 10[superscript -5]). For some diseases, this increase was individually significant:2.07 X for Multiple Sclerosis (MS) (P = 6.5 X 10 [superscript -9]) and for Crohn's Disease (CD) (P = 1.3 X 10[superscript -3]); all analyses of autoimmune diseases excluded the well-studied MHC region. Additionally, we found that GWAS loci from other related traits also explained significant heritability. The union of all autoimmune disease loci explained 7.15 X more MS heritability than known MS SNPs (P 20,000 Rheumatoid Arthritis (RA) samples typed on ImmunoChip, with 2.37 X more heritability from all SNPs at GWAS loci (P = 2.3 X 10[superscript -6]) and more heritability from all autoimmune disease loci (P < 1 X 10[superscript -16]) compared to known RA SNPs (including those identified in this cohort). Our methods adjust for LD between SNPs, which can bias standard estimates of heritability from SNPs even if all causal variants are typed. By comparing adjusted estimates, we hypothesize that the genome-wide distribution of causal variants is enriched for low-frequency alleles, but that causal variants at known GWAS loci are skewed towards common alleles. These findings have important ramifications for fine-mapping study design and our understanding of complex disease architecture.National Institutes of Health (U.S.) (Grant R03HG006731)National Institutes of Health (U.S.) (Fellowship F32GM106584

    Impaired innate interferon induction in severe therapy resistant atopic asthmatic children

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    Deficient type I interferon-β and type III interferon-λ induction by rhinoviruses has previously been reported in mild/moderate atopic asthmatic adults. No studies have yet investigated if this occurs in severe therapy resistant asthma (STRA). Here, we show that compared with non-allergic healthy control children, bronchial epithelial cells cultured ex vivo from severe therapy resistant atopic asthmatic children have profoundly impaired interferon-β and interferon-λ mRNA and protein in response to rhinovirus (RV) and polyIC stimulation. Severe treatment resistant asthmatics also exhibited increased virus load, which negatively correlated with interferon mRNA levels. Furthermore, uninfected cells from severe therapy resistant asthmatic children showed lower levels of Toll-like receptor-3 mRNA and reduced retinoic acid inducible gene and melanoma differentiation-associated gene 5 mRNA after RV stimulation. These data expand on the original work, suggesting that the innate anti-viral response to RVs is impaired in asthmatic tissues and demonstrate that this is a feature of STRA

    GENERAL ASPECTS REGARDING THE GROWTH FRESHWATER FISH IN CUBES, AN ALTERNATIVE FOR AQUACULTURE IN ROMANIA

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    Due to the increased consumption of fish, as an alternative to achieving healthy population nutrition, the development of European aquaculture also shows an increasing trend. At present, freshwater culture is about 42% of total European fish production. Valuable species, from an economic point of view, can be reared in intensive systems in cages on running waters or ponds, combined with less valuable species. There are also new species that are gradually becoming increasingly important for the fish industry in Europe. Freshwater aquaculture in Romania is based on rainbow trout and carp which are still predominant species, but there is significant demand for valuable fish species [11,12,16]. Â
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