A proton source in the ALPHA apparatus for precision measurements of antihydrogen and hydrogen

The apparent lack of antimatter within our local solar system, the Milky Way, and at Galactic boundaries is inconsistent with the Big Bang hypothesis. This disagreement has motivated many experiments to compare the properties and behaviour of antimatter and matter. The ALPHA (Antihydrogen Laser PHysics Apparatus) experiment produce, trap and study antihydrogen. This synthesis involves antiprotons sourced from the limited schedule of the Antiproton Decelerator facility. The restricted availability hinders the number of novel antiproton experiments, whichcould potentially increase the number of trapped antihydrogen atoms per Antiproton Decelerator cycle. Some of these studies can be performed using a substitute for antiprotons, such as protons, allowing the limited antiprotons to be used during the implementation of their results. This research demonstrates a method that adapts an existing Penning trap to produce protons on demand within reasonable operating time scales of minutes. The availability of protons enables the consideration of new physics studies within ALPHA, including hydrogen formation, trapping, and possibly in situ hydrogen-antihydrogen comparisons. The study produced protons from radiofrequency-drivenelectrons through electron impact ionisation of the cryogenic Penning trap residual gas. The resulting positive ions were sympathetically cooled and compressed by positrons. All positive ions, except protons, were ejected from the trapping potentials using the autoresonance method. The remaining trapped population is approximately (0.9 − 1.2) × 106 protons. This research proves the feasibility of generating protons within the ALPHA apparatus, paving the way for future prospects of hydrogen generation

A Tale of Two Tails: Exploring Stellar Populations in the Tidal Tails of NGC 3256

We have developed an observing program using deep, multiband imaging to probe the chaotic regions of tidal tails in search of an underlying stellar population, using NGC 3256's 400 Myr twin tidal tails as a case study. These tails have different colours of $u - g = 1.05 \pm 0.07$ and $r - i = 0.13 \pm 0.07$ for NGC 3256W, and $u - g = 1.26 \pm 0.07$ and $r - i = 0.26 \pm 0.07$ for NGC 3256E, indicating different stellar populations. These colours correspond to simple stellar population ages of $288^{+11}_{-54}$ Myr and $841^{+125}_{-157}$ Myr for NGC 3256W and NGC 3256E, respectively, suggesting NGC 3256W's diffuse light is dominated by stars formed after the interaction, while light in NGC 3256E is primarily from stars that originated in the host galaxy. Using a mixed stellar population model, we break our diffuse light into two populations: one at 10 Gyr, representing stars pulled from the host galaxies, and a younger component, whose age is determined by fitting the model to the data. We find similar ages for the young populations of both tails, ($195^{-13}_{+0}$ and $170^{-70}_{+44}$ Myr for NGC 3256W and NGC 3256E, respectively), but a larger percentage of mass in the 10 Gyr population for NGC 3256E ($98^{+1}_{-3}\%$ vs $90^{+5}_{-6}\%$). Additionally, we detect 31 star cluster candidates in NGC 3256W and 19 in NGC 2356E, with median ages of 141 Myr and 91 Myr, respectively. NGC 3256E contains several young (< 10 Myr), low mass objects with strong nebular emission, indicating a small, recent burst of star formation.Comment: Accepted for publication in MNRAS. 16 pages, 19 figure

GWIPS-viz: 2018 update

The GWIPS-viz browser (http://gwips.ucc.ie/) is an on-line genome browser which is tailored for exploring ribosome profiling (Ribo-seq) data. Since its publication in 2014, GWIPS-viz provides Ribo-seq data for an additional 14 genomes bringing the current total to 23. The integration of new Ribo-seq data has been automated thereby increasing the number of available tracks to 1792, a 10-fold increase in the last three years. The increase is particularly substantial for data derived from human sources. Following user requests, we added the functionality to download these tracks in bigWig format. We also incorporated new types of data (e.g. TCP-seq) as well as auxiliary tracks from other sources that help with the interpretation of Ribo-seq data. Improvements in the visualization of the data have been carried out particularly for bacterial genomes where the Ribo-seq data are now shown in a strand specific manner. For higher eukaryotic datasets, we provide characteristics of individual datasets using the RUST program which includes the triplet periodicity, sequencing biases and relative inferred A-site dwell times. This information can be used for assessing the quality of Ribo-seq datasets. To improve the power of the signal, we aggregate Ribo-seq data from several studies into Global aggregate tracks for each genome

SSGAC Polygenic Scores (PGSs) in the National Longitudinal Study of Adolescent to Adult Health (Add Health)

This document describes the construction of polygenic scores (PGSs) associated with various phenotypes for respondents participating in the National Longitudinal Study of Adolescent to Adult Health (Add Health) by the Social Science Genetic Association Consortium (SSGAC). Research has shown that many outcomes of interest in the health, behavioral, and social sciences are influenced by genetics (Domingue et al. 20161; Plomin et al. 20162; Turkheimer 20003). For most human traits/behaviors, commonly referred to as phenotypes, it appears that the genetic influence on the phenotype is highly polygenic; i.e., there is no single gene that can account for the association between genetic variance and variance in the outcome. Instead, the influence of genetics on most phenotypes appears to be due to many small associations across thousands, and possibly millions, of individual single-nucleotide polymorphisms (SNPs, pronounced snips) (Chabris et al. 20154). Polygenic Scores allow researchers to avoid the methodological complexities of including thousands, or millions, of covariates in their analyses by condensing, into a single measure, the associations between individual SNPs and the phenotype of interest (Plomin, Haworth, and Davis 20095)

Polygenic Index Inventories Documentation

This guide documents the key information regarding the construction and use of polygenic indexes (PGIs) for the National Longitudinal Study of Adolescent to Adult Health (Add Health) as part of the Resource Profile and User Guide of the Polygenic Index Repository. Summary Information About PGIs Polygenic indexes (PGIs) are constructed using the same general approach (described below) and have the same substantive meaning as polygenic scores (PGSs, used more prominently in social science genomics contexts) and genetic risk scores (GRSs, used more prominently in the medical contexts). Here, we provide a brief summary of how the PGIs were constructed (please see the Methods section of Becker et al. for a more detailed description). We refer the reader to the relevant tables of Becker et al. where more information can be found

Observation of the effect of gravity on the motion of antimatter

Einstein’s general theory of relativity from 19151 remains the most successful description of gravitation. From the 1919 solar eclipse2 to the observation of gravitational waves3, the theory has passed many crucial experimental tests. However, the evolving concepts of dark matter and dark energy illustrate that there is much to be learned about the gravitating content of the universe. Singularities in the general theory of relativity and the lack of a quantum theory of gravity suggest that our picture is incomplete. It is thus prudent to explore gravity in exotic physical systems. Antimatter was unknown to Einstein in 1915. Dirac’s theory4 appeared in 1928; the positron was observed5 in 1932. There has since been much speculation about gravity and antimatter. The theoretical consensus is that any laboratory mass must be attracted6 by the Earth, although some authors have considered the cosmological consequences if antimatter should be repelled by matter7,8,9,10. In the general theory of relativity, the weak equivalence principle (WEP) requires that all masses react identically to gravity, independent of their internal structure. Here we show that antihydrogen atoms, released from magnetic confinement in the ALPHA-g apparatus, behave in a way consistent with gravitational attraction to the Earth. Repulsive ‘antigravity’ is ruled out in this case. This experiment paves the way for precision studies of the magnitude of the gravitational acceleration between anti-atoms and the Earth to test the WEP

GWIPS-viz: development of a ribo-seq genome browser

We describe the development of GWIPS-viz (http://gwips.ucc.ie), an online genome browser for viewing ribosome profiling data. Ribosome profiling (ribo-seq) is a recently developed technique that provides genome-wide information on protein synthesis (GWIPS) in vivo. It is based on the deep sequencing of ribosome-protected messenger RNA (mRNA) fragments, which allows the ribosome density along all mRNA transcripts present in the cell to be quantified. Since its inception, ribo-seq has been carried out in a number of eukaryotic and prokaryotic organisms. Owing to the increasing interest in ribo-seq, there is a pertinent demand for a dedicated ribo-seq genome browser. GWIPS-viz is based on The University of California Santa Cruz (UCSC) Genome Browser. Ribo-seq tracks, coupled with mRNA-seq tracks, are currently available for several genomes: human, mouse, zebrafish, nematode, yeast, bacteria (Escherichia coli K12, Bacillus subtilis), human cytomegalovirus and bacteriophage lambda. Our objective is to continue incorporating published ribo-seq data sets so that the wider community can readily view ribosome profiling information from multiple studies without the need to carry out computational processing

Sheep Updates 2015 - Merredin

This session covers fourteen papers from different authors: 1. The Sheep Industry Business Innovation project, Bruce Mullan, Sheep Industry Development Director, Department of Agriculture and Food, Western Australia 2. Western Australian sheep stocktake, Kate Pritchett and Kimbal Curtis, Research Officers, Department of Agriculture and Food, Western Australia 3. Wool demand and supply - short term volatility, long term opportunities, Chris Wilcox, Principal of Poimena Analysis 4. Myths, Facts and the role of animal welfare in farming, Lynne Bradshaw, president, RSPCA WA 5. Latest research and development on breech strike prevention, Geoff Lindon, Manager Productivity and Animal Welfare, AWI 6. Lamb Survival Initiative and 100% Club, Katherine Davies, Development Officer, Department of Agriculture and Food, Western Australia 7. How to boost your lamb survival, Joe Young, Sheep Consultant, R.B. Young and Son 8. Using genomic technology to increase genetic gain, Stephen Lee, School of Animal and Veterinary Sciences, University of Adelaide and Sheep Cooperative Research Centre (CRC) 9. A case study of sheep breeding using the latest genetic and genomic technology, Dawson Bradford Producer, Hillcroft Farms, Narrogin WA 10. The impact of lamb growth on meat quality, Khama Kelman Department of Agriculture and Food, Western Australia 11. Economics of feed lotting - to feed-lot or not?, Lucy Anderton, Economist, Department of Agriculture and Food, Western Australia 12. National Livestock Identification System (NLIS) for sheep and goats - what is the NLIS database? Jaq Pearson Biosecurity Officer, Department of Agriculture and Food, Western Australia 13. Sheep industry traineeships - encouraging a new generation of farmers, Jackie Jarvis, Consultant, Agrifood Labour & Skills 14. Opportunities and challenges facing youth in the sheep and wool industry, Ben Patrick, Yarrawonga Stu

Sheep Updates 2015 - Ravensthorpe

This session covers fourteen papers from different authors: 1. The Sheep Industry Business Innovation project, Bruce Mullan, Sheep Industry Development Director, Department of Agriculture and Food, Western Australia 2. Western Australian sheep stocktake, Kate Pritchett and Kimbal Curtis, Research Officers, Department of Agriculture and Food, Western Australia 3. Wool demand and supply - short term volatility, long term opportunities, Chris Wilcox, Principal of Poimena Analysis 4. Lifetime management for maternal ewes, Mike Hyder, Research Officer, Department of Agriculture and Food, Western Australia 5. National Livestock Identification System (NLIS) for sheep and goats - what is the NLIS database? Leigh Sonnermann, Biosecurity Officer, Department of Agriculture and Food, Western Australia 6. Myths, Facts and the role of animal welfare in farming, Lynne Bradshaw, president, RSPCA WA 7. Latest research and development on breech strike prevention, Geoff Lindon, Manager Productivity and Animal Welfare, AWI 8. Lamb Survival Initiative and 100% Club, Katherine Davies, Development Officer, Department of Agriculture and Food, Western Australia 9. How to boost your lamb survival, Joe Young, Sheep Consultant, R.B. Young and Son 10. Using genomic technology to increase genetic gain, Stephen Lee, School of Animal and Veterinary Sciences, University of Adelaide and Sheep Cooperative Research Centre (CRC) & Ian Robertson, Merinotech WA 11. Economics of feed lotting - to feed-lot or not?, Lucy Anderton, Economist, Department of Agriculture and Food, Western Australia 12. Anameka and other shrubs to fill feed gaps, Hayley Norman CSIRO & Ed Barrett-Lennard UWA & Department of Agriculture and Food, Western Australia 13. Sheep industry traineeships - encouraging a new generation of farmers, Jackie Jarvis, Consultant, Agrifood Labour & Skills 14. Opportunities and challenges facing youth in the sheep and wool industry, Ben Patrick, Yarrawonga Stu