1,767 research outputs found
Mass spectrometry screening of Arabica coffee roasting: A non-target and non-volatile approach by EASI-MS and ESI-MS.
Coffee roasting needs precise control and innovative techniques that are economically viable to monitor and improve its consistency. In this study, mass spectrometry was used as a tool to screen chemical markers that appear on the surface of coffee beans (whole bean) along the roasting process. A non-target and non-volatile approach was used with an ambient technique (EASI) coupled to a single quadrupole mass analyzer to monitor roasting chemical changes in the coffee bean. Green (raw), soft, medium, dark and very dark roasted coffee beans showed a decrease in ions in the range of m/z 500â600, whereas an increase in abundance in the m/z 800â900 range was clearly observed in the most roasted coffees. A multivariate approach through PCA separated the different roasts in 70% of the variance using PC1 and PC2. The major ions in the range of m/z 500â600 were characterized by ESI-MS and also HPLC-fluorescence as the N-alkanoyltryptamides, surface constituents of coffee wax layer which are almost fully degraded in darker roasts. The ions in the range of m/z 800â900 were characterized as di-and triacylglicerols and its increase during the roasting process was systematically observed. For these classes of chemical markers of the roasting process, ESI-MS showed also the sodium and potassium adducts with good relative abundances
Genome-wide association study for femur-related traits in broilers.
Abstract: Due to the intense selection for heavier and faster growing broilers, metabolic disorders such as skeletal problems became a worldwide concern. Advances in genome-wide association study (GWAS) methodologies increased the possibility of elucidating the genetic architecture controlling bone integrity traits. Therefore, the aim of this study was to perform a GWAS to identify potential genetic markers and candidate genes associated with femur traits in a paternal broiler line developed by Embrapa. To this, three femur bone-related traits were evaluated in 1,433 chickens: dry matter (FDM), ash content (FAC) and breaking strength (FBS). Chickens were genotyped using the 600K AffymetrixÂź AxiomÂź HD panel. A total of 16 regions associated to FAC, being a significant SNP in the GGA19 (rs317696422) and 15 suggestive SNPs in the GGA1, GGA2, GGA3, GGA5, GGA8, GGA13, GGA19 and GGA24. For FDM, only one SNP (GGA1) was significantly associated and was located in the DSCAM gene. For the FBS, two suggestive regions (GGA12 and GGA15) were found and no QTLs were described for this trait in these regions. According to the results, new candidate genes and miRNAs related to ossification, such as TPVR2, gga-mir-146a and PCP4 were associated to important femur traits in the broiler line under study. Resumo:Devido Ă intensa seleção de frangos de corte mais pesados ​​e de crescimento mais rĂĄpido, distĂșrbios metabĂłlicos, como problemas esquelĂ©ticos, tornaram-se uma preocupação mundial. Avanços em metodologias de estudo de associação genĂŽmica ampla (GWAS) aumentaram a possibilidade de elucidar a arquitetura genĂ©tica controlando caracterĂsticas de integridade Ăłssea. Portanto, o objetivo deste estudo foi realizar um GWAS para identificar potenciais marcadores genĂ©ticos e genes candidatos associados Ă s caracterĂsticas do fĂȘmur em uma linhagem de frangos de corte paterna desenvolvida pela Embrapa. Para isso, trĂȘs caracterĂsticas relacionadas ao osso do fĂȘmur foram avaliadas em 1.433 aves: matĂ©ria seca (FDM), teor de cinzas (FAC) e resistĂȘncia Ă ruptura (FBS). As galinhas foram genotipadas usando o painel 600y AffymetrixÂź AxiomÂź HD. Um total de 16 regiĂ”es associadas ao FAC, sendo um significativo SNP no GGA19 (rs317696422) e 15 SNPs sugestivos no GGA1, GGA2, GGA3, GGA5, GGA8, GGA13, GGA19 e GGA24. Para FDM, apenas um SNP (GGA1) foi significativamente associado e foi localizado no gene DSCAM. Para o FBS, duas regiĂ”es sugestivas (GGA12 e GGA15) foram encontradas e nĂŁo foram descritos QTLs para essa caracterĂstica nessas regiĂ”es. De acordo com os resultados, novos genes candidatos e miRNAs relacionados Ă ossificação, como TPVR2, gga-mir-146a e PCP4, foram associados a importantes caracterĂsticas do fĂȘmur na linha de frangos em estudo
Exploring the genetic architecture of feed efficiency traits in chickens.
Abstract: Chicken feed efficiency (FE) traits are the most important economic traits in broiler production. Several studies evaluating genetic factors affecting food consumption in chickens are available. However, most of these studies identified genomic regions containing putative quantitative trait loci for each trait separately. It is still a challenge to find common gene networks related to these traits. Therefore, here, a genome-wide association study (GWAS) was conducted to explore candidate genomic regions responsible for Feed Intake (FI), Body Weight Gain (BWG) and Feed Conversion Ratio (FCR) traits and their gene networks. A total of 1430 broilers from an experimental population was genotyped with the high density Affymetrix 600K SNP array. A total of 119 associated SNPs located in 20 chromosomes were identified, where some of them were common in more than one FE trait. In addition, novel genomic regions were prospected considering the SNPs dominance effects and sex interaction, identifying putative candidate genes only when these effects were fit in the model. Relevant candidate genes such as ATRNL1, PIK3C2A, PTPRN2, SORCS3 and gga-mir-1759 were highlighted in this study helping to elucidate the genomic architecture of feed efficiency traits. These results provide new insights on the mechanisms underlying the consumption and utilization of food in chickens
Charge separation relative to the reaction plane in Pb-Pb collisions at TeV
Measurements of charge dependent azimuthal correlations with the ALICE
detector at the LHC are reported for Pb-Pb collisions at TeV. Two- and three-particle charge-dependent azimuthal correlations in
the pseudo-rapidity range are presented as a function of the
collision centrality, particle separation in pseudo-rapidity, and transverse
momentum. A clear signal compatible with a charge-dependent separation relative
to the reaction plane is observed, which shows little or no collision energy
dependence when compared to measurements at RHIC energies. This provides a new
insight for understanding the nature of the charge dependent azimuthal
correlations observed at RHIC and LHC energies.Comment: 12 pages, 3 captioned figures, authors from page 2 to 6, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/286
Multi-particle azimuthal correlations in p-Pb and Pb-Pb collisions at the CERN Large Hadron Collider
Measurements of multi-particle azimuthal correlations (cumulants) for charged
particles in p-Pb and Pb-Pb collisions are presented. They help address the
question of whether there is evidence for global, flow-like, azimuthal
correlations in the p-Pb system. Comparisons are made to measurements from the
larger Pb-Pb system, where such evidence is established. In particular, the
second harmonic two-particle cumulants are found to decrease with multiplicity,
characteristic of a dominance of few-particle correlations in p-Pb collisions.
However, when a gap is placed to suppress such correlations,
the two-particle cumulants begin to rise at high-multiplicity, indicating the
presence of global azimuthal correlations. The Pb-Pb values are higher than the
p-Pb values at similar multiplicities. In both systems, the second harmonic
four-particle cumulants exhibit a transition from positive to negative values
when the multiplicity increases. The negative values allow for a measurement of
to be made, which is found to be higher in Pb-Pb collisions at
similar multiplicities. The second harmonic six-particle cumulants are also
found to be higher in Pb-Pb collisions. In Pb-Pb collisions, we generally find
which is indicative of a Bessel-Gaussian
function for the distribution. For very high-multiplicity Pb-Pb
collisions, we observe that the four- and six-particle cumulants become
consistent with 0. Finally, third harmonic two-particle cumulants in p-Pb and
Pb-Pb are measured. These are found to be similar for overlapping
multiplicities, when a gap is placed.Comment: 25 pages, 11 captioned figures, 3 tables, authors from page 20,
published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/87
Multiplicity dependence of jet-like two-particle correlations in p-Pb collisions at = 5.02 TeV
Two-particle angular correlations between unidentified charged trigger and
associated particles are measured by the ALICE detector in p-Pb collisions at a
nucleon-nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum
range 0.7 5.0 GeV/ is examined,
to include correlations induced by jets originating from low
momen\-tum-transfer scatterings (minijets). The correlations expressed as
associated yield per trigger particle are obtained in the pseudorapidity range
. The near-side long-range pseudorapidity correlations observed in
high-multiplicity p-Pb collisions are subtracted from both near-side
short-range and away-side correlations in order to remove the non-jet-like
components. The yields in the jet-like peaks are found to be invariant with
event multiplicity with the exception of events with low multiplicity. This
invariance is consistent with the particles being produced via the incoherent
fragmentation of multiple parton--parton scatterings, while the yield related
to the previously observed ridge structures is not jet-related. The number of
uncorrelated sources of particle production is found to increase linearly with
multiplicity, suggesting no saturation of the number of multi-parton
interactions even in the highest multiplicity p-Pb collisions. Further, the
number scales in the intermediate multiplicity region with the number of binary
nucleon-nucleon collisions estimated with a Glauber Monte-Carlo simulation.Comment: 23 pages, 6 captioned figures, 1 table, authors from page 17,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/161
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