912 research outputs found
Species by Environment Interactions Affect Pyrrolizidine Alkaloid Expression in Senecio jacobaea, Senecio aquaticus, and Their Hybrids
We examined the effects of water and nutrient availability on the expression of the defense pyrrolizidine alkaloids (PAs) in Senecio jacobaea and S. aquaticus. Senecio jacobaea, and S. aquaticus are adapted to different natural habitats, characterized by differing abiotic conditions and different selection pressures from natural enemies. We tested if PA concentration and diversity are plastic over a range of water and nutrient treatments, and also whether such plasticity is dependent on plant species. We also tested the hypothesis that hybridization may contribute to PA diversity within plants, by comparing PA expression in parental species to that in artificially generated F1 hybrids, and also in later generation natural hybrids between S. jacobaea and S. aquaticus. We showed that total PA concentration in roots and shoots is not dependent on species, but that species determines the pattern of PA diversification. Pyrrolizidine alkaloid diversity and concentration are both dependent on environmental factors. Hybrids produce a putatively novel PA, and this PA is conserved in natural hybrids, that are backcrossed to S. jacobaea. Natural hybrids that are backcrossed several times to S. jacobaea are with regard to PA diversity significantly different from S. jacobaea but not from S. aquaticus, while F1 hybrids are in all cases more similar to S. jacobaea. These results collectively suggest that PA diversity is under the influence of natural selection
The Impact of HAART on the Respiratory Complications of HIV Infection: Longitudinal Trends in the MACS and WIHS Cohorts
Objective: To review the incidence of respiratory conditions and their effect on mortality in HIV-infected and uninfected individuals prior to and during the era of highly active antiretroviral therapy (HAART). Design: Two large observational cohorts of HIV-infected and HIV-uninfected men (Multicenter AIDS Cohort Study [MACS]) and women (Women's Interagency HIV Study [WIHS]), followed since 1984 and 1994, respectively. Methods: Adjusted odds or hazards ratios for incident respiratory infections or non-infectious respiratory diagnoses, respectively, in HIV-infected compared to HIV-uninfected individuals in both the pre-HAART (MACS only) and HAART eras; and adjusted Cox proportional hazard ratios for mortality in HIV-infected persons with lung disease during the HAART era. Results: Compared to HIV-uninfected participants, HIV-infected individuals had more incident respiratory infections both pre-HAART (MACS, odds ratio [adjusted-OR], 2.4; 95% confidence interval [CI], 2.2-2.7; p<0.001) and after HAART availability (MACS, adjusted-OR, 1.5; 95%CI 1.3-1.7; p<0.001; WIHS adjusted-OR, 2.2; 95%CI 1.8-2.7; p<0.001). Chronic obstructive pulmonary disease was more common in MACS HIV-infected vs. HIV-uninfected participants pre-HAART (hazard ratio [adjusted-HR] 2.9; 95%CI, 1.02-8.4; p = 0.046). After HAART availability, non-infectious lung diseases were not significantly more common in HIV-infected participants in either MACS or WIHS participants. HIV-infected participants in the HAART era with respiratory infections had an increased risk of death compared to those without infections (MACS adjusted-HR, 1.5; 95%CI, 1.3-1.7; p<0.001; WIHS adjusted-HR, 1.9; 95%CI, 1.5-2.4; p<0.001). Conclusion: HIV infection remained a significant risk for infectious respiratory diseases after the introduction of HAART, and infectious respiratory diseases were associated with an increased risk of mortality. Β© 2013 Gingo et al
An evaluation of family physicians' educational needs and experiences in health promotion and disease prevention in Poland and Lithuania - a qualitative study
ReikΕ‘miniai ΕΎodΕΎiai: LigΕ³ prevencija; Sveikatos stiprinimas; Ε eimos gydytojai; Ε eimos gydytojΕ³ rengimas; Ε eimos gydytojΕ³ Ε‘vietimo poreikiai; Disease prevention; Family physicians; Family physicians educational needs; Health promotion; Training of family physician
Multi-ancestry fine mapping of interferon lambda and the outcome of acute hepatitis C virus infection
Clearance of acute infection with hepatitis C virus (HCV) is associated with the chr19q13.13 region containing the rs368234815 (TT/ΞG) polymorphism. We fine-mapped this region to detect possible causal variants that may contribute to HCV clearance. First, we performed sequencing of IFNL1-IFNL4 region in 64 individuals sampled according to rs368234815 genotype: TT/clearance (Nβ=β16) and ΞG/persistent (Nβ=β15) (genotype-outcome concordant) or TT/persistent (Nβ=β19) and ΞG/clearance (Nβ=β14) (discordant). 25 SNPs had a difference in counts of alternative allele >5 between clearance and persistence individuals. Then, we evaluated those markers in an association analysis of HCV clearance conditioning on rs368234815 in two groups of European (692 clearance/1 025 persistence) and African ancestry (320 clearance/1 515 persistence) individuals. 10/25 variants were associated (Pβ<β0.05) in the conditioned analysis leaded by rs4803221 (Pβvalue =β4.9βΓβ10β04) and rs8099917 (Pβvalue =β5.5βΓβ10β04). In the European ancestry group, individuals with the haplotype rs368234815ΞG/rs4803221C were 1.7Γ more likely to clear than those with the rs368234815ΞG/rs4803221G haplotype (Pβvalue =β3.6βΓβ10β05). For another nearby SNP, the haplotype of rs368234815ΞG/rs8099917T was associated with HCV clearance compared to rs368234815ΞG/rs8099917G (OR: 1.6, Pβvalue =β1.8βΓβ10β04). We identified four possible causal variants: rs368234815, rs12982533, rs10612351 and rs4803221. Our results suggest a main signal of association represented by rs368234815, with contributions from rs4803221, and/or nearby SNPs including rs8099917
Reporting quality of randomized trials in the diet and exercise literature for weight loss
BACKGROUND: To adequately assess individual studies and synthesize quantitative research on weight loss studies, transparent reporting of data is required. The authors examined the reporting quality of randomized trials in the weight loss literature, focusing exclusively on subject characteristics as they relate to enrollment, allocation, and follow-up. METHODS: An extensive literature review, which included a computerized search of the MEDLINE database, manual searches of bibliographic references, and cross-referencing of 92 review articles was conducted. A checklist, based on CONSORT recommendations, was used to collect information on whether or not authors reported age, gender, co-morbid disease, medication use, race/ethnicity, and postmenopausal status. Also tracked was whether or not initial and final sample size was reported and stratified by gender. RESULTS: Of 604 possible articles, 231 articles met eligibility criteria. Important subject characteristics were not reported as the following breakdown indicates: age (11%), gender (4%), race/ethnicity (86%), co-morbid disease states (34%), and medication use (92%). Additionally, 21% of articles failed to report initial sample size by gender while 69% neglected to report final sample size by gender. CONCLUSION: Inadequate reporting can create difficulties with interpretation and can lead to biased results receiving false credibility. The quality of reporting for weight loss studies needs considerable improvement
Understanding Plant-Microbe Interactions for Phytoremediation of Petroleum-Polluted Soil
Plant-microbe interactions are considered to be important processes determining
the efficiency of phytoremediation of petroleum pollution, however relatively
little is known about how these interactions are influenced by petroleum
pollution. In this experimental study using a microcosm approach, we examined
how plant ecophysiological traits, soil nutrients and microbial activities were
influenced by petroleum pollution in Phragmites australis, a
phytoremediating species. Generally, petroleum pollution reduced plant
performance, especially at early stages of plant growth. Petroleum had negative
effects on the net accumulation of inorganic nitrogen from its organic forms
(net nitrogen mineralization (NNM)) most likely by decreasing the inorganic
nitrogen available to the plants in petroleum-polluted soils. However, abundant
dissolved organic nitrogen (DON) was found in petroleum-polluted soil. In order
to overcome initial deficiency of inorganic nitrogen, plants by dint of high
colonization of arbuscular mycorrhizal fungi might absorb some DON for their
growth in petroleum-polluted soils. In addition, through using a real-time
polymerase chain reaction method, we quantified hydrocarbon-degrading bacterial
traits based on their catabolic genes (i.e. alkB (alkane
monooxygenase), nah (naphthalene dioxygenase) and
tol (xylene monooxygenase) genes). This enumeration of
target genes suggests that different hydrocarbon-degrading bacteria experienced
different dynamic changes during phytoremediation and a greater abundance of
alkB was detected during vegetative growth stages. Because
phytoremediation of different components of petroleum is performed by different
hydrocarbon-degrading bacteria, plantsβ ability of phytoremediating
different components might therefore vary during the plant life cycle.
Phytoremediation might be most effective during the vegetative growth stages as
greater abundances of hydrocarbon-degrading bacteria containing
alkB and tol genes were observed at these
stages. The information provided by this study enhances our understanding of the
effects of petroleum pollution on plant-microbe interactions and the roles of
these interactions in the phytoremediation of petroleum-polluted soil
Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
The inclusive and dijet production cross-sections have been measured for jets
containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass
energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The
measurements use data corresponding to an integrated luminosity of 34 pb^-1.
The b-jets are identified using either a lifetime-based method, where secondary
decay vertices of b-hadrons in jets are reconstructed using information from
the tracking detectors, or a muon-based method where the presence of a muon is
used to identify semileptonic decays of b-hadrons inside jets. The inclusive
b-jet cross-section is measured as a function of transverse momentum in the
range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet
cross-section is measured as a function of the dijet invariant mass in the
range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets
and the angular variable chi in two dijet mass regions. The results are
compared with next-to-leading-order QCD predictions. Good agreement is observed
between the measured cross-sections and the predictions obtained using POWHEG +
Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet
cross-section. However, it does not reproduce the measured inclusive
cross-section well, particularly for central b-jets with large transverse
momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final
version published in European Physical Journal
Observation of associated near-side and away-side long-range correlations in βsNN=5.02ββTeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (ΞΟ) and pseudorapidity (ΞΞ·) are measured in βsNN=5.02ββTeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1ββΞΌb-1 of data as a function of transverse momentum (pT) and the transverse energy (Ξ£ETPb) summed over 3.1<Ξ·<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|ΞΞ·|<5) βnear-sideβ (ΞΟβΌ0) correlation that grows rapidly with increasing Ξ£ETPb. A long-range βaway-sideβ (ΞΟβΌΟ) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small Ξ£ETPb, is found to match the near-side correlation in magnitude, shape (in ΞΞ· and ΞΟ) and Ξ£ETPb dependence. The resultant ΞΟ correlation is approximately symmetric about Ο/2, and is consistent with a dominant cosβ‘2ΞΟ modulation for all Ξ£ETPb ranges and particle pT
Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV
The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of βs = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pTβ₯20 GeV and pseudorapidities {pipe}Ξ·{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}Ξ·{pipe}<0. 8) for jets with 60β€pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2β€{pipe}Ξ·{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. Β© 2013 CERN for the benefit of the ATLAS collaboration
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