Observation and Prediction of Soil Water Under Different Types of Vegetation

Soil water trends were monitored during the 1971 growing season on the Anoka Sand Plain in east-central Minnesota. Soils were sampled under four vegetation densities, ranging from old field through increasing amounts of oak overstory. There was no difference over the sampled period in total soil water content (to 100 cm) on the four sites. Differences were found in water content of individual soil horizons, and especially in the surface horizon (0 to 10 cm). A model of evapotranspiration was used to simulate the observed trends and the prediction and observations were closely correlated (r2 ~ 0 .91)

Charged rho meson production in neutrino-induced reactions at E_nu = 10 GeV

The neutrinoproduction of charged $\rho$ mesons on nuclei and nucleons is investigated for the first time at moderate energies ($\approx$ 10 GeV), using the date obtained with SKAT bubble chamber. No strong nuclear effects are observed in $\rho^+$ and $\rho^-$ production. The fractions of charged and neutral pions originating from $\rho$ decays are obtained and compared with higher energy data. From analysis of the obtained and available data on $\rho^+$ and $K^{*+}$(892) neutrinoproduction, the strangeness suppression factor in the quark string fragmentation is extracted: $\lambda_s = 0.18\pm0.03$. Estimations are obtained for cross sections of quasiexclusive single $\rho^+$ and coherent $\rho^+$ neutrinoproduction on nuclei. The estimated coherent cross section $\sigma_{\rho^+}^{coh}$ = (0.29$\pm0.16)\cdot 10^{-38}$ cm$^2$ is compatible with theoretical predictions.Comment: 7 pages, 6 figure

Perceived barriers to assessing understanding and appreciation of informed consent in clinical trials: A mixed-method study

INTRODUCTION: Participants and research professionals often overestimate how well participants understand and appreciate consent information for clinical trials, and experts often vary in their determinations of participant\u27s capacity to consent to research. Past research has developed and validated instruments designed to assess participant understanding and appreciation, but the frequency with which they are utilized is unknown. METHODS: We administered a survey to clinical researchers working with older adults or those at risk of cognitive impairment ( RESULTS: We found that using a validated assessment of consent is relatively uncommon, being used by only 44% of researchers who had an opportunity. Factors that predicted adoption of validated assessments included not seeing the study sponsor as a barrier, positive attitudes toward assessments, and being confident that they had the resources needed to implement an assessment. The perceived barriers to adopting validated assessments of consent included lack of awareness, lack of knowledge, being unsure of how to administer such an assessment, and the burden associated with implementing this practice. CONCLUSIONS: Increasing the use of validated assessments of consent will require educating researchers on the practice and emphasizing very practical assessments, and may require Institutional Review Boards (IRBs) or study sponsors to champion the use of assessments

Strangeness Production at RHIC in the Perturbative Regim

We investigate strange quark production in Au-Au collisions at RHIC in the framework of the Parton Cascade Model(PCM). The yields of (anti-) strange quarks for three production scenarios -- primary-primary scattering, full scattering, and full production -- are compared to a proton-proton baseline. Enhancement of strange quark yields in central Au-Au collisions compared to scaled p-p collisions increases with the number of secondary interactions. The centrality dependence of strangeness production for the three production scenarios is studied as well. For all production mechanisms, the strangeness yield increases with $(N_{\rm part})^{4/3}$. The perturbative QCD regime described by the PCM is able to account for up to 50% of the observed strangeness at RHIC.Comment: 10 pages, 4 figures, IOP forma

Strange prospects for LHC energies

Strange quark and hadron production will be studied at the Large Hadron Collider (LHC) energies in order to explore the properties of both pp and heavy-ion collisions. The ALICE experiment will be specifically efficient in the strange sector with the identification of baryons and mesons over a wide range of transverse momentum. Dedicated measurements are proposed for investigating chemical equilibration and bulk properties. Strange particles can also help to probe kinematical regions where hard processes and pQCD dominate. We try to anticipate here several ALICE analyses to be performed as the first Pb--Pb and pp data will be available.Comment: 5 pages, 2 figures. To appear in the proceedings of Hot Quarks 2006, Villasimius, Italy, 15-20 May 200

The continuum limit of quark number susceptibilities

We report the continuum limit of quark number susceptibilities in quenched QCD. Deviations from ideal gas behaviour at temperature T increase as the lattice spacing is decreased from T/4 to T/6, but a further decrease seems to have very little effect. The measured susceptibilities are 20% lower than the ideal gas values, and also 10% below the hard thermal loop (HTL) results. The off-diagonal susceptibility is several orders of magnitude smaller than the HTL results. We verify a strong correlation between the lowest screening mass and the susceptibility. We also show that the quark number susceptibilities give a reasonable account of the Wroblewski parameter, which measures the strangeness yield in a heavy-ion collision.Comment: 8 pages, 5 figure

The Quark Gluon Plasma: lattice computations put to experimental test

I describe how lattice computations are being used to extract experimentally relevant features of the quark gluon plasma. I deal specifically with relaxation times, photon emissivity, strangeness yields, event by event fluctuations of conserved quantities and hydrodynamic flow. Finally I give evidence that the plasma is liquid-like in some ways.Comment: Review talk at the QCD02 meeting, IIT Kanpur, Indi

Hypoxia induced downregulation of hepcidin is mediated by platelet derived growth factor BB

OBJECTIVE: Hypoxia affects body iron homeostasis; however, the underlying mechanisms are incompletely understood. DESIGN: Using a standardised hypoxia chamber, 23 healthy volunteers were subjected to hypoxic conditions, equivalent to an altitude of 5600 m, for 6 h. Subsequent experiments were performed in C57BL/6 mice, CREB-H knockout mice, primary hepatocytes and HepG2 cells. RESULTS: Exposure of subjects to hypoxia resulted in a significant decrease of serum levels of the master regulator of iron homeostasis hepcidin and elevated concentrations of platelet derived growth factor (PDGF)-BB. Using correlation analysis, we identified PDGF-BB to be associated with hypoxia mediated hepcidin repression in humans. We then exposed mice to hypoxia using a standardised chamber and observed downregulation of hepatic hepcidin mRNA expression that was paralleled by elevated serum PDGF-BB protein concentrations and higher serum iron levels as compared with mice housed under normoxic conditions. PDGF-BB treatment in vitro and in vivo resulted in suppression of both steady state and BMP6 inducible hepcidin expression. Mechanistically, PDGF-BB inhibits hepcidin transcription by downregulating the protein expression of the transcription factors CREB and CREB-H, and pharmacological blockade or genetic ablation of these pathways abrogated the effects of PDGF-BB toward hepcidin expression. CONCLUSIONS: Hypoxia decreases hepatic hepcidin expression by a novel regulatory pathway exerted via PDGF-BB, leading to increased availability of circulating iron that can be used for erythropoiesis

The yields of light meson resonances in neutrinonuclear interactions at <E_nu> = 10 GeV

The total yields of the all well-established light mesonic resonances (up to the $\phi$(1020) meson) are estimated in neutrinonuclear interactions at < E_nu > = 10 GeV, using the data obtained with SKAT bubble chamber. For some resonances, the yields in the forward and backward hemispheres in the hadronic c.m.s. are also extracted. From the comparison of the obtained and available higher-energy data, an indication is obtained that the resonance yields rise almost linearly as a function of the mean mass of the neutrinoproduced hadronic system. The fractions of pions originating from the light resonance decays are inferred.Comment: 15 pages, 7 figure