Design and implementation of a prototype active infrared sensor controlled automatic sliding door for mitigation of coronavirus disease 2019 (COVID-19)

The door is an essential part of any structure that provides access and security of lives and properties. The manual operation of a door could be cumbersome and laborious when the traffic volume is high. Also, it has been observed that doors could serve as a medium of spreading the deadly coronavirus disease 2019 (COVID-19) infection. Therefore, a prototype automatic sliding door that plays a crucial role in curbing the spread of this infectious diseases has been designed and implemented in this paper. The design of the prototype sliding door is in two parts namely; the structural part and the automation part. The structural design of the door was achieved using the Microsoft Visio 2016 while the design of the automation system was achieved using express printed circuit board. The implementation of the structural part was achieved using 1 inch particle board while the implementation of the automation system was based on the components like the active infrared sensor, resistors (10 kΩ), capacitor (1000 µF), transistors (TIP41 Q8, BC548 Q7), LED indicators, press button switch, pulley system, drive belt, stepper motor (IP65), and ATMEGA 8 microcontroller. The result of the tests carried out on the door showed that the prototype automatic sliding door was characterized by average opening time, closing time, delay time, and optimal sensing range of 3.10 s, 3.05 s, 5.72 s, and 23.5 cm, respectively. It can therefore be concluded from this work that the prototype automatic sliding door is effective in overriding the manual operation of the door

\u3cem\u3eIn vitro\u3c/em\u3e Digestibility and Methane Production of Two Tropical Grasses: Plant Spacing and Grazing Frequency

This study was carried out to investigate the influence of plant spacing and grazing frequency on the in vitro gas production, digestibility, and methane production of Guinea grass (Megathyrsus maximus) and Elephant grass (Cenchrus purpureus) in the humid southwest part of Nigeria. The experiment was laid in a 2 x 2 x 2 factorial arrangement in a split-split-plot design with three replicates, which consisted of two grazing frequency (3 and 6-week) as the main plot, two grass species: Guinea grass (M. maximus) and Elephant grass (C. purpureus) as the sub plot and two plant spacing (1m x 1m and 0.5m x 1m) as the sub-sub plot. A total area of 2496 m2 of an existing plot established April 2019 was used in conducting this experiment. In May 2020, the grasses were cut back at the commencement of this experiment to 15cm above ground surface and NPK 20:10:10 fertilizer was applied 8 days after cut back at the rate of 120 kg N/ha. The result showed a significant (Pin vitro gas production, digestibility (IVDMD) and methane gas production. The CP content of C. purpureus (18.14 %) grazed at 3-week GF with 1 m x 1 m spacing was significantly (PM. maximus grazed at 3-week at the narrower spacing with the IVDMD been the highest (64.53% DM) and the least gas volume was produced by C. purpureus grazed at 3-week with a narrower spacing, whereas the least digested was C. purpureus grazed at 6-week with narrower spacing. The methane production of C. purpureus grazed at 3-week with wider spacing was the least (5.53 ml/200mg DM) while the highest methane was produced by M. maximus also grazed at 3-week with 0.5m x 1m spacing though not statistically (P\u3e0.05) different from the methane of same species with same plant spacing at 6-week grazing frequency. It can be concluded that grazing at 3-week grazing frequency and narrower spacing will help reduce methane for C. purpureus and improve digestibility for M. maximus

EVALUATION OF THE AGRONOMIC PERFORMANCE AND NUTRITIVE VALUES OF TEPHROSIA BRACTEOLATA GUILL. & PERR. AND GMELINA ARBOREA ROXB PRUNNINGS AT DIFFERENT STAGES OF GROWTH

This study was carried out to investigate the growth, dry matter yield and chemical composition of Tephrosia bracteolata and Gmelina arborea at Teaching and Research Farm, Federal University of Agriculture, Abeokuta, Nigeria. The objective of this study was to evaluate the effect of different stages of growth of T. bracteolata and G. arborea on their agronomic performance, herbage yield and nutritive value in the humid zone of Nigeria. Data were collected at 8, 12, 16 and 20 weeks after planting (WAP). Results showed that T. bracteolata attained the height of 161 cm at 20 WAP, though not significantly different from the height at 16 WAP. The leaf number (24), branch number (7) and dry matter yield of T. bracteolata were recorded highest at 16 WAP. The height of G. arborea was on constant increase throughout the experimental period. The crude protein (CP) and ether extract (EE) contents of the two browse plants were highest at 8 WAP and thereafter, declined throughout the experimental period. Fibre fractions, the neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL) had a least value for both browse species at 8 WAP and highest values at 20 WAP. From the study, considering the dry matter yield and nutritive value, T. bracteolata being an annual species, can be harvested at 16 WAP when the quality and quantity will support livestock productivity and can be conserved to be fed to ruminant animals during dry season when feed availability and quality are extremely low. However, planting of G. arborea should be encouraged being a perennial browse plant that will support livestock productivity during the dry season in the tropics. In conclusion, T. bracteolata and G. arborea grow rapidly and are recommended as forage of high nutritive values that meet ruminant animal protein requirements especially during the dry season

Antihydrogen and mirror-trapped antiproton discrimination: Discriminating between antihydrogen and mirror-trapped antiprotons in a minimum-B trap

Recently, antihydrogen atoms were trapped at CERN in a magnetic minimum (minimum-B) trap formed by superconducting octupole and mirror magnet coils. The trapped antiatoms were detected by rapidly turning off these magnets, thereby eliminating the magnetic minimum and releasing any antiatoms contained in the trap. Once released, these antiatoms quickly hit the trap wall, whereupon the positrons and antiprotons in the antiatoms annihilated. The antiproton annihilations produce easily detected signals; we used these signals to prove that we trapped antihydrogen. However, our technique could be confounded by mirror-trapped antiprotons, which would produce seemingly-identical annihilation signals upon hitting the trap wall. In this paper, we discuss possible sources of mirror-trapped antiprotons and show that antihydrogen and antiprotons can be readily distinguished, often with the aid of applied electric fields, by analyzing the annihilation locations and times. We further discuss the general properties of antiproton and antihydrogen trajectories in this magnetic geometry, and reconstruct the antihydrogen energy distribution from the measured annihilation time history.Comment: 17 figure

Physics with antihydrogen

Performing measurements of the properties of antihydrogen, the bound state of an antiproton and a positron, and comparing the results with those for ordinary hydrogen, has long been seen as a route to test some of the fundamental principles of physics. There has been much experimental progress in this direction in recent years, and antihydrogen is now routinely created and trapped and a range of exciting measurements probing the foundations of modern physics are planned or underway. In this contribution we review the techniques developed to facilitate the capture and manipulation of positrons and antiprotons, along with procedures to bring them together to create antihydrogen. Once formed, the antihydrogen has been detected by its destruction via annihilation or field ionization, and aspects of the methodologies involved are summarized. Magnetic minimum neutral atom traps have been employed to allow some of the antihydrogen created to be held for considerable periods. We describe such devices, and their implementation, along with the cusp magnetic trap used to produce the first evidence for a low-energy beam of antihydrogen. The experiments performed to date on antihydrogen are discussed, including the first observation of a resonant quantum transition and the analyses that have yielded a limit on the electrical neutrality of the anti-atom and placed crude bounds on its gravitational behaviour. Our review concludes with an outlook, including the new ELENA extension to the antiproton decelerator facility at CERN, together with summaries of how we envisage the major threads of antihydrogen physics will progress in the coming years

Measurement of the scintillation time spectra and pulse-shape discrimination of low-energy beta and nuclear recoils in liquid argon with DEAP-1

The DEAP-1 low-background liquid argon detector was used to measure scintillation pulse shapes of electron and nuclear recoil events and to demonstrate the feasibility of pulse-shape discrimination (PSD) down to an electron-equivalent energy of 20 keV. In the surface dataset using a triple-coincidence tag we found the fraction of beta events that are misidentified as nuclear recoils to be $<1.4\times 10^{-7}$ (90% C.L.) for energies between 43-86 keVee and for a nuclear recoil acceptance of at least 90%, with 4% systematic uncertainty on the absolute energy scale. The discrimination measurement on surface was limited by nuclear recoils induced by cosmic-ray generated neutrons. This was improved by moving the detector to the SNOLAB underground laboratory, where the reduced background rate allowed the same measurement with only a double-coincidence tag. The combined data set contains $1.23\times10^8$ events. One of those, in the underground data set, is in the nuclear-recoil region of interest. Taking into account the expected background of 0.48 events coming from random pileup, the resulting upper limit on the electronic recoil contamination is $<2.7\times10^{-8}$ (90% C.L.) between 44-89 keVee and for a nuclear recoil acceptance of at least 90%, with 6% systematic uncertainty on the absolute energy scale. We developed a general mathematical framework to describe PSD parameter distributions and used it to build an analytical model of the distributions observed in DEAP-1. Using this model, we project a misidentification fraction of approx. $10^{-10}$ for an electron-equivalent energy threshold of 15 keV for a detector with 8 PE/keVee light yield. This reduction enables a search for spin-independent scattering of WIMPs from 1000 kg of liquid argon with a WIMP-nucleon cross-section sensitivity of $10^{-46}$ cm$^2$, assuming negligible contribution from nuclear recoil backgrounds.Comment: Accepted for publication in Astroparticle Physic

Usability, acceptability, and feasibility of the World Health Organization Labour Care Guide: A mixed-methods, multicountry evaluation.

Introduction The World Health Organization’s (WHO) Labour Care Guide (LCG) is a “next-generation” partograph based on WHO’s latest intrapartum care recommendations. It aims to optimize clinical care provided to women and their experience of care. We evaluated the LCG’s usability, feasibility, and acceptability among maternity care practitioners in clinical settings. Methods Mixed-methods evaluation with doctors, midwives, and nurses in 12 health facilities across Argentina, India, Kenya, Malawi, Nigeria, and Tanzania. Purposively sampled and trained practitioners applied the LCG in low-risk women during labor and rated experiences, satisfaction, and usability. Practitioners were invited to focus group discussions (FGDs) to share experiences and perceptions of the LCG, which were subjected to framework analysis. Results One hundred and thirty-six practitioners applied the LCG in managing labor and birth of 1,226 low-risk women. The majority of women had a spontaneous vaginal birth (91.6%); two cases of intrapartum stillbirths (1.63 per 1000 births) occurred. Practitioner satisfaction with the LCG was high, and median usability score was 67.5%. Practitioners described the LCG as supporting precise and meticulous monitoring during labor, encouraging critical thinking in labor management, and improving the provision of woman-centered care. Conclusions The LCG is feasible and acceptable to use across different clinical settings and can promote woman-centered care, though some design improvements would benefit usability. Implementing the LCG needs to be accompanied by training and supportive supervision, and strategies to promote an enabling environment (including updated policies on supportive care interventions, and ensuring essential equipment is available)