To maximise the yield of winter wheat, it is necessary to further optimise modern cultivation technologies to adapt them to changing environmental conditions. One of the aspects of plant adaptation ...to unfavourable abiotic factors is the active functioning of the photosynthetic apparatus, which depends on the number of nutrients applied. This paper investigates the effect of fertilisation on the state of the pigment complex of winter wheat plants in the Southern Steppe of Ukraine. Two varieties of winter wheat were selected for the study: Shestopalivka and Mason. The scheme of the experiment included the application of fertilisers during sowing (К0; К12) and foliar processing with various tank mixtures (urea; urea + magnesium sulphate; urea + magnesium sulphate + potassium monophosphate). The pigment content was determined by grinding fresh leaves of winter wheat with further addition of a solvent in the form of acetone. The pigments were measured using a spectrophotometer. The results of the studies showed that before foliar fertilisation, the content of chlorophyll a and carotenoids was higher in the leaves of plants of the Shestopalivka variety. At the same time, the content of chlorophyll b was higher for Mason plants by 17%, which may be a consequence of the adaptation of plants of this variety to a lack of light. A decrease in the pigment content in the leaves of plants of all experimental variants caused by the active growth of the photosynthesising surface and a decrease in the total dry matter mass was observed on day 3 after the foliar fertilisation. There was no significant difference between varieties in the content of photosynthetic pigments during this period. On the 10th day after foliar spraying, an increase in the content of chlorophyll a and b was observed for both studied varieties, which may be the result of the adaptation of the photosynthetic apparatus of winter wheat plants to lighting conditions. Foliar fertilisation of winter wheat plants with a tank mixture of urea with magnesium sulphate and potassium monophosphate contributed to a further increase in the content of chlorophyll a by 12-23% and chlorophyll b by 5-37%, depending on the variety compared to the control. The results of the conducted research indicate the high efficiency of the complex application of nitrogen-phosphorus-potassium fertilisers for foliar spraying of winter wheat plants at the stage of BBCH 31 both on the background of pre-sowing potassium fertilizers and without it
Seismic measuring stations do not only record seismic waves. They also pick up tremors caused by other factors: these are known as seismic background noise. In normal conditions, this environmental ...background is steady over a long time. This article presents the influence of high reduction of human activity due to COVID-19 initial lockdown on ground vibration in the Large Hadron Collider tunnel at the European Organization for Nuclear Research.
The CERN RD53 collaboration was founded to tackle the extraordinary challenges associated with the design of pixel readout chips for the innermost layers of particle trackers at future high energy ...physics experiments. Around 20 institutions are involved in the collaboration, which has the support of both ATLAS and CMS experiments. The goals of the collaboration include the comprehensive understanding of radiation effects in the 65 nm technology, the development of tools and methodology to efficiently design large complex mixed signal chips and, ultimately, the development of a full size readout chip featuring a 400 × 400 pixel array with 50μm pitch. In August 2017, the collaboration submitted the large scale chip RD53A, integrating a matrix of 400 × 192 pixels and embodying three different analog front-end designs. This work discusses the characteristic of the RD53A chip, with some emphasis on the analog processors, and presents the first test results on the pixel array.
•High particle rates and radiation levels will be reached at the HL-LHC.•New pixel chips for the phase II upgrades of CMS and ATLAS are required.•The RD53A chip has been designed in the framework of the RD53 Collaboration.•Three analog front-ends flavors are integrated in RD53A.•The paper presents the main preliminary results coming from RD53A characterization.
A search for squarks and gluinos in final states containing jets, missing transverse momentum and no electrons or muons is presented. The data were recorded by the ATLAS experiment in s=7 TeV ...proton–proton collisions at the Large Hadron Collider. No excess above the Standard Model background expectation was observed in 35 pb−1 of analysed data. Gluino masses below 500 GeV are excluded at the 95% confidence level in simplified models containing only squarks of the first two generations, a gluino octet and a massless neutralino. The exclusion increases to 870 GeV for equal mass squarks and gluinos. In MSUGRA/CMSSM models with tanβ=3, A0=0 and μ>0, squarks and gluinos of equal mass are excluded below 775 GeV. These are the most stringent limits to date.
We have determined the theoretical predictions for the cross sections of squark and gluino production at
pp and
pp colliders (Tevatron and LHC) in next-to-leading order of supersymmetric QCD. By ...reducing the dependence on the renormalization/factorization scale considerably, the theoretically predicted values for the cross sections are much more stable if these higher-order corrections are implemented. If squarks and gluinos are discovered, this improved stability translates into a reduced error on the masses, as extracted experimentally from the size of the production cross sections. The cross sections increase significantly if the next-to-leading order corrections are included at a renormalization/factorization scale near the average mass of the produced massive particles. This rise results in improved lower bounds on squark and gluino masses. By contrast, the shape of the transverse-momentum and rapidity distributions remains nearly unchanged when the next-to-leading order corrections are included.
The upgrade of the Compact Muon Solenoid (CMS) crystal electromagnetic calorimeter (ECAL), which will operate at the High Luminosity Large Hadron Collider (HL-LHC), will achieve a timing resolution ...of around 30 ps for high energy photons and electrons. In this talk we will discuss the benefits of precision timing for the ECAL event reconstruction at HL-LHC. Simulation studies on the timing properties of PbWO crystals, as well as the impact of the photosensors and the readout electronics on the timing performance, will be presented. Test beam studies on the timing performance of PbWO4 crystals with various photosensors and readout electronics will be shown.
An experimental setup is operational at the Central Cryogenics Laboratory of the European Organization for Nuclear Research to measure the cooling mechanisms of superfluid 4 He (He II) from prepared ...Rutherford-type superconducting cable stacks to a stagnant He II bath. For novel magnets designed for the so-called high-luminosity large hadron collider upgrade, a segment of a fully impregnated Nb 3 Sn 11T dipole magnet was measured. A dataset on the thermal behavior is presented, with homogeneous heat inputs of up to approximately 4.8 mW cm -3 corresponding to an average steady-state temperature of 3.1 K for the inner layer and 4.0 K for the outer layer when cooled via a 1.9 K He II bath. We discuss the steady state as well as transient behavior observed.
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