Field scale limited irrigation scenarios for water policy strategies

ABSTRACT. Approaches to reducing irrigation inputs to crops have been studied for the past 50 to 60 years in research settings. Fewer efforts have been made to document limited irrigation responses over a number of seasons on commercial fields. This study compared farm−based irrigation management (FARM) with best management practices (BMP), late initiation of irrigation (LATE), and a restricted allocation (ALLOC). These irrigation management strategies each occupied 1/8 of a center pivot system in southwest Nebraska in continuous corn production, on four cooperating farms, which were replicated at the same sites for 3 to 6 years. Irrigation variables were achieved by irrigating or not irrigating, or by speeding up or slowing down the center pivot. When the grain yields and irrigation amounts were normalized each year using the FARM treatment as the basis, on average for three of four locations, the BMP treatment yielded equal to the FARM treatment, the LATE treatment yielded 93 % of the FARM treatment and the ALLOC yielded 84 % of the FARM treatment. At the same time, it took 76 % and 57 % of the water for the LATE and ALLOC treatments, respectively, to achieve these yields. The adjusted gross returns (yield price – irrigation treatment costs) of the irrigation treatments were analyzed for each location. When the gross returns were normalized using the FARM treatment as the basis, FARM and BMP returns were equal across combinations of high and low input commodity prices and pumping costs. The LATE treatment gross return was 95 % of FARM return. The gross return for the ALLOC treatment was 85 % to 91 % of the FARM treatment. The higher the water costs, the lower the difference between the highest and lowest returning water treatments. Relationships between evapotranspiratio

Prototype Lead Tungstate Calorimeter Test for TPEX

Tests of a prototype lead tungstate calorimeter were made over two weeks at the end of September, 2019, at the DESY II Test Beam Facility in Hamburg, Germany. The purpose of these tests was to gain experience with the construction, operation, and performance of a simple lead tungstate calorimeter, and also to compare a traditional triggered readout scheme with a streaming readout approach. These tests are important for the proposed Two-Photon Exchange experiment at the DESY test beam facility and for work towards a future electromagnetic calorimeter that could be used in an Electron-Ion Collider detector. Details on all aspects of the test, the subsequent analysis, and the results are presented.Comment: 7 pages, 15 figure

Measurement of the Luminosity in the ZEUS Experiment at HERA II

The luminosity in the ZEUS detector was measured using photons from electron bremsstrahlung. In 2001 the HERA collider was upgraded for operation at higher luminosity. At the same time the luminosity-measuring system of the ZEUS experiment was modified to tackle the expected higher photon rate and synchrotron radiation. The existing lead-scintillator calorimeter was equipped with radiation hard scintillator tiles and shielded against synchrotron radiation. In addition, a magnetic spectrometer was installed to measure the luminosity independently using photons converted in the beam-pipe exit window. The redundancy provided a reliable and robust luminosity determination with a systematic uncertainty of 1.7%. The experimental setup, the techniques used for luminosity determination and the estimate of the systematic uncertainty are reported.Comment: 25 pages, 11 figure

A chemical probe based on the PreQ1 metabolite enables transcriptome-wide mapping of binding sites

The role of metabolite-responsive riboswitches in regulating gene expression in bacteria is well known and makes them useful systems for the study of RNA-small molecule interactions. Here, we study the PreQ1 riboswitch system, assessing sixteen diverse PreQ1-derived probes for their ability to selectively modify the class-I PreQ1 riboswitch aptamer covalently. For the most active probe (11), a diazirine-based photocrosslinking analog of PreQ1, X-ray crystallography and gel-based competition assays demonstrated the mode of binding of the ligand to the aptamer, and functional assays demonstrated that the probe retains activity against the full riboswitch. Transcriptome-wide mapping using Chem-CLIP revealed a highly selective interaction between the bacterial aptamer and the probe. In addition, a small number of RNA targets in endogenous human transcripts were found to bind specifically to 11, providing evidence for candidate PreQ1 aptamers in human RNA. This work demonstrates a stark influence of linker chemistry and structure on the ability of molecules to crosslink RNA, reveals that the PreQ1 aptamer/ligand pair are broadly useful for chemical biology applications, and provides insights into how PreQ1, which is similar in structure to guanine, interacts with human RNAs

A Search for Jet Handedness in Hadronic Z0Z^0 Decays

We have searched for signatures of polarization in hadronic jets from $Z^0 \to q \bar{q}$ decays using the ``jet handedness'' method. The polar angle asymmetry induced by the high SLC electron-beam polarization was used to separate quark jets from antiquark jets, expected to be left- and right-polarized, respectively. We find no evidence for jet handedness in our global sample or in a sample of light quark jets and we set upper limits at the 95% C.L. of 0.063 and 0.099 respectively on the magnitude of the analyzing power of the method proposed by Efremov {\it et al.}Comment: Revtex, 8 pages, 2 figure

A Large Hadron Electron Collider at CERN

This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and electron-ion physics. The LHeC is designed to run synchronously with the LHC in the twenties and to achieve an integrated luminosity of O(100) fb$^{-1}$. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC

Measurement of inclusive D*+- and associated dijet cross sections in photoproduction at HERA

Inclusive photoproduction of D*+- mesons has been measured for photon-proton centre-of-mass energies in the range 130 < W < 280 GeV and a photon virtuality Q^2 < 1 GeV^2. The data sample used corresponds to an integrated luminosity of 37 pb^-1. Total and differential cross sections as functions of the D* transverse momentum and pseudorapidity are presented in restricted kinematical regions and the data are compared with next-to-leading order (NLO) perturbative QCD calculations using the "massive charm" and "massless charm" schemes. The measured cross sections are generally above the NLO calculations, in particular in the forward (proton) direction. The large data sample also allows the study of dijet production associated with charm. A significant resolved as well as a direct photon component contribute to the cross section. Leading order QCD Monte Carlo calculations indicate that the resolved contribution arises from a significant charm component in the photon. A massive charm NLO parton level calculation yields lower cross sections compared to the measured results in a kinematic region where the resolved photon contribution is significant.Comment: 32 pages including 6 figure

Molecular Mechanism of Capacitative Calcium Entry Deficits in Familial Alzheimer’s Disease

Poster PresentationPresenilin (PS) is the catalytic subunit of the gamma-secretase which is responsible for the cleavage of amyloid precursor protein to form beta amyloid (Aβ). Mutations in PS associated with familial Alzheimer’s disease (FAD) increase the Aβ plaques formation in the brain and cause neurodegeneration. Apart from this, FAD-linked PS mutations have been demonstrated to disrupt intracellular calcium (Ca2+) regulation. Accumulating evidence suggests that Ca2+ disruption may play a proximal role in the AD pathogenesis. Mutant PS exaggerated Ca2+ release from the endoplasmic reticulum (ER). It also attenuated Ca2+ entry through the capacitative Ca2+ entry (CCE) pathway, yet, the mechanism is not fully understood. Using a human neuroblast cell line SH-SY5Y and Ca2+ imaging technique, we observed CCE deficits in FAD-linked PS1-M146L retroviral infected cell. The attenuation of CCE in PS1 mutant cells was not mediated by the down-regulation of STIM1 and Orai1 expression, the known essential molecular players in the CCE pathway. Instead, we identified a molecular interaction between PS and STIM1 proteins by immunoprecipitation. On the other hand, immunofluorescence staining showed a significant reduction in puncta formation after ER Ca2+ depleted by thapsigargin in cells infected with PS1-M146L as compared to the wild type PS1 infected cells. Taken together, our results suggest a molecular mechanism for the CCE deficits in FAD associated with PS1 mutations. The interaction of mutant PS1 with STIM1 exerts a negative impact on its oligomerization and/or its interaction with Orai1. Our results may suggest molecular targets for the development of therapeutic agents that help to treat the disease.published_or_final_versio

Hard Two-Photon Contribution to Elastic Lepton-Proton Scattering: Determined by the OLYMPUS Experiment

The OLYMPUS collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, $R_{2\gamma}$, a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01~GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of $\approx 20\degree$ to $80\degree$. The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved GEM and MWPC detectors at $12\degree$, as well as symmetric M{\o}ller/Bhabha calorimeters at $1.29\degree$. A total integrated luminosity of 4.5~fb$^{-1}$ was collected. In the extraction of $R_{2\gamma}$, radiative effects were taken into account using a Monte Carlo generator to simulate the convolutions of internal bremsstrahlung with experiment-specific conditions such as detector acceptance and reconstruction efficiency. The resulting values of $R_{2\gamma}$, presented here for a wide range of virtual photon polarization $0.456<\epsilon<0.978$, are smaller than some hadronic two-photon exchange calculations predict, but are in reasonable agreement with a subtracted dispersion model and a phenomenological fit to the form factor data.Comment: 5 pages, 3 figures, 2 table