Modified Lead-zirconate-titanate for Pyroelectric Sensors

Pyroelectric sensors based on ceramic materials have found applications in IR detectionin defence and civil systems. To develop suitable ceramic material for IR detector applications,a modified PZT system with compositional formula Pb1-xSmx(Zr0.58Fe0.18Mn0.02Nb0.2Ti0.02)O3  where0  x  0.025 was synthesised by conventional solid state reaction method. The materials werecharacterised for their properties like dielectric and pyroelectric coefficient. Hysteresis loop wasrecorded at room temperature. The sample with 2 mole per cent samarium (Sm) substitutions wasfound to be more promising for sensor application based on its high material's figure of merit(FOM). Sensors fabricated with this material were integrated with FET amplifier. The devicesconfigured with compensating element were evaluated for different chopping frequencies.  Thevalue of material's FOM, FD, and detectivity, D*, were determined from measured parameters andwere,  3.6 x 10-5 Pa-1/2 and 2 x 108 cmHz1/2/W, respectively

Tyrosine Supplementation A Nutraceutical Approach to Counter Heat Stress Induced Cognitive Decline

Supplementation of tyrosine, non-essential amino acid, and precursor of catecholamine was found to ameliorate the heat-induced alterations in latencies of event-related potential P300 and contingent negative variation. Here we present the effect of tyrosine supplementation on heat stress (exposure to ambient temperature 45 oC and relative humidity 30 %) induced alterations in behavior (attention, mood) and levels of plasma monoamines. Ten healthy male participants received a placebo food bar or tyrosine-containing food bar (6.5 g in 50 g) 90 min before heat stress exposure of 90 min. Plasma and urine samples were assayed for catecholamine levels, their precursor, and metabolites using high-performance liquid chromatography. A computer-based automated test battery was used to assess attention and mood by profile of mood states questionnaire. A significantly higher plasma tyrosine (p<0.001) leading to an increased norepinephrine (p<0.05) levels in the tyrosine supplemented group was observed. Selective (p<0.001) and sustained attention (p<0.02) in the tyrosine group were significantly better compared to the placebo group. Reaction time and anger scores decreased (p<0.001) with tyrosine supplementation. It may be concluded that tyrosine supplementation improves heat stress-induced decrement in attention by maintaining the synthesis and turnover of norepinephrine

The effect of minimum quantity lubrication in the intermittent turning of magnesium based on vibration signals

The present work shows an experimental investigation on intermittent turning based on vibration signals. The dependence of vibrations on the feed rate, minimum quantity lubrication (MQL) flow rate and the type of the interruption of the workpiece is evaluated. The results indicate that a part of the vibrations depends on the flow rate of the MQL system and its interaction with the feed rate, finding no dependency on the type of interruption. The influence of the MQL system is greater when machining at the lower feed rate. In addition, a strong relation between surface roughness and vibrations is identified. However, this relation is quite different depending on the environment used. In general, under dry conditions, the higher the vibrations the higher the surface roughness, while the opposite occurs when the MQL system is used.publishe

2022 Upgrade and Improved Low Frequency Camera Sensitivity for CMB Observation at the South Pole

Constraining the Galactic foregrounds with multi-frequency Cosmic Microwave Background (CMB) observations is an essential step towards ultimately reaching the sensitivity to measure primordial gravitational waves (PGWs), the sign of inflation after the Big-Bang that would be imprinted on the CMB. The BICEP Array telescope is a set of multi-frequency cameras designed to constrain the energy scale of inflation through CMB B-mode searches while also controlling the polarized galactic foregrounds. The lowest frequency BICEP Array receiver (BA1) has been observing from the South Pole since 2020 and provides 30 GHz and 40 GHz data to characterize the Galactic synchrotron in our CMB maps. In this paper, we present the design of the BA1 detectors and the full optical characterization of the camera including the on-sky performance at the South Pole. The paper also introduces the design challenges during the first observing season including the effect of out-of-band photons on detectors performance. It also describes the tests done to diagnose that effect and the new upgrade to minimize these photons, as well as installing more dichroic detectors during the 2022 deployment season to improve the BA1 sensitivity. We finally report background noise measurements of the detectors with the goal of having photon noise dominated detectors in both optical channels. BA1 achieves an improvement in mapping speed compared to the previous deployment season.Comment: Proceedings of SPIE Astronomical Telescopes + Instrumentation 2022 (AS22

Measurements of differential production cross sections for a Z boson in association with jets in pp collisions at root s=8 TeV

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Search for leptophobic Z ' bosons decaying into four-lepton final states in proton-proton collisions at root s=8 TeV

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Search for black holes and other new phenomena in high-multiplicity final states in proton-proton collisions at root s=13 TeV

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Search for high-mass diphoton resonances in proton-proton collisions at 13 TeV and combination with 8 TeV search

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Search for heavy resonances decaying into a vector boson and a Higgs boson in final states with charged leptons, neutrinos, and b quarks

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