Emitter-site selective photoelectron circular dichroism of trifluoromethyloxirane

The angle-resolved inner-shell photoionization of R-trifluoromethyloxirane, C3H3F3O, is studied experimentally and theoretically. Thereby, we investigate the photoelectron circular dichroism (PECD) for nearly-symmetric O 1s and F 1s electronic orbitals, which are localized on different molecular sites. The respective dichroic $\beta_{1}$ and angular distribution $\beta_{2}$ parameters are measured at the photoelectron kinetic energies from 1 to 16 eV by using variably polarized synchrotron radiation and velocity map imaging spectroscopy. The present experimental results are in good agreement with the outcome of ab initio electronic structure calculations. We report a sizable chiral asymmetry $\beta_{1}$ of up to about 9% for the K-shell photoionization of oxygen atom. For the individual fluorine atoms, the present calculations predict asymmetries of similar size. However, being averaged over all fluorine atoms, it drops down to about 2%, as also observed in the present experiment. Our study demonstrates a strong emitter- and site-sensitivity of PECD in the one-photon inner-shell ionization of this chiral molecule

Innovative sponge-based moving bed-osmotic membrane bioreactor hybrid system using a new class of draw solution for municipal wastewater treatment

© 2016 Elsevier Ltd. For the first time, an innovative concept of combining sponge-based moving bed (SMB) and an osmotic membrane bioreactor (OsMBR), known as the SMB-OsMBR hybrid system, were investigated using Triton X-114 surfactant coupled with MgCl2 salt as the draw solution. Compared to traditional activated sludge OsMBR, the SMB-OsMBR system was able to remove more nutrients due to the thick-biofilm layer on sponge carriers. Subsequently less membrane fouling was observed during the wastewater treatment process. A water flux of 11.38 L/(m2 h) and a negligible reverse salt flux were documented when deionized water served as the feed solution and a mixture of 1.5 M MgCl2 and 1.5 mM Triton X-114 was used as the draw solution. The SMB-OsMBR hybrid system indicated that a stable water flux of 10.5 L/(m2 h) and low salt accumulation were achieved in a 90-day operation. Moreover, the nutrient removal efficiency of the proposed system was close to 100%, confirming the effectiveness of simultaneous nitrification and denitrification in the biofilm layer on sponge carriers. The overall performance of the SMB-OsMBR hybrid system using MgCl2 coupled with Triton X-114 as the draw solution demonstrates its potential application in wastewater treatment

The Mid-Infrared Instrument for the James Webb Space Telescope, III: MIRIM, The MIRI Imager

In this article, we describe the MIRI Imager module (MIRIM), which provides broad-band imaging in the 5 - 27 microns wavelength range for the James Webb Space Telescope. The imager has a 0"11 pixel scale and a total unobstructed view of 74"x113". The remainder of its nominal 113"x113" field is occupied by the coronagraphs and the low resolution spectrometer. We present the instrument optical and mechanical design. We show that the test data, as measured during the test campaigns undertaken at CEA-Saclay, at the Rutherford Appleton Laboratory, and at the NASA Goddard Space Flight Center, indicate that the instrument complies with its design requirements and goals. We also discuss the operational requirements (multiple dithers and exposures) needed for optimal scientific utilization of the MIRIM.Comment: 29 pages, 9 figure

General Gauge Mediation with Gauge Messengers

We generalize the General Gauge Mediation formalism to allow for the possibility of gauge messengers. Gauge messengers occur when charged matter fields of the susy-breaking sector have non-zero F-terms, which leads to tree-level, susy-breaking mass splittings in the gauge fields. A classic example is that SU(5) / SU(3) x SU(2) x U(1) gauge fields could be gauge messengers. We give a completely general, model independent, current-algebra based analysis of gauge messenger mediation of susy-breaking to the visible sector. Characteristic aspects of gauge messengers include enhanced contributions to gaugino masses, (tachyonic) sfermion mass-squareds generated already at one loop, and also at two loops, and significant one-loop A-terms, already at the messenger scale.Comment: 79 pages, 5 figure

Massive stars as thermonuclear reactors and their explosions following core collapse

Nuclear reactions transform atomic nuclei inside stars. This is the process of stellar nucleosynthesis. The basic concepts of determining nuclear reaction rates inside stars are reviewed. How stars manage to burn their fuel so slowly most of the time are also considered. Stellar thermonuclear reactions involving protons in hydrostatic burning are discussed first. Then I discuss triple alpha reactions in the helium burning stage. Carbon and oxygen survive in red giant stars because of the nuclear structure of oxygen and neon. Further nuclear burning of carbon, neon, oxygen and silicon in quiescent conditions are discussed next. In the subsequent core-collapse phase, neutronization due to electron capture from the top of the Fermi sea in a degenerate core takes place. The expected signal of neutrinos from a nearby supernova is calculated. The supernova often explodes inside a dense circumstellar medium, which is established due to the progenitor star losing its outermost envelope in a stellar wind or mass transfer in a binary system. The nature of the circumstellar medium and the ejecta of the supernova and their dynamics are revealed by observations in the optical, IR, radio, and X-ray bands, and I discuss some of these observations and their interpretations.Comment: To be published in " Principles and Perspectives in Cosmochemistry" Lecture Notes on Kodai School on Synthesis of Elements in Stars; ed. by Aruna Goswami & Eswar Reddy, Springer Verlag, 2009. Contains 21 figure

Nunalleq, Stories from the Village of Our Ancestors:Co-designing a multivocal educational resource based on an archaeological excavation

This work was funded by the UK-based Arts and Humanities Research Council through grants (AH/K006029/1) and (AH/R014523/1), a University of Aberdeen IKEC Award with additional support for travel and subsistence from the University of Dundee, DJCAD Research Committee RS2 project funding. Thank you to the many people who contributed their support, knowledge, feedback, voices and faces throughout the project, this list includes members of the local community, colleagues, specialists, students, and volunteers. If we have missed out any names we apologize but know that your help was appreciated. Jimmy Anaver, John Anderson, Alice Bailey, Kieran Baxter, Pauline Beebe, Ellinor Berggren, Dawn Biddison, Joshua Branstetter, Brendan Body, Lise Bos, Michael Broderick, Sarah Brown, Crystal Carter, Joseph Carter, Lucy Carter, Sally Carter, Ben Charles, Mary Church, Willard Church, Daniele Clementi, Annie Cleveland, Emily Cleveland, Joshua Cleveland, Aron Crowell, Neil Curtis, Angie Demma, Annie Don, Julia Farley, Veronique Forbes, Patti Fredericks, Tricia Gillam, Sean Gleason, Sven Haakanson, Cheryl Heitman, Grace Hill, Diana Hunter, Joel Isaak, Warren Jones, Stephan Jones, Ana Jorge, Solveig Junglas, Melia Knecht, Rick Knecht, Erika Larsen, Paul Ledger, Jonathan Lim Soon, Amber Lincoln, Steve Luke, Francis Lukezic, Eva Malvich, Pauline Matthews, Roy Mark, Edouard Masson-MacLean, Julie Masson-MacLean, Mhairi Maxwell, Chuna Mcintyre, Drew Michael, Amanda Mina, Anna Mossolova, Carl Nicolai Jr, Chris Niskanen, Molly Odell, Tom Paxton, Lauren Phillips, Lucy Qin, Charlie Roberts, Chris Rowe, Rufus Rowe,Chris Rowland, John Rundall, Melissa Shaginoff, Monica Shah, Anna Sloan, Darryl Small Jr, John Smith, Mike Smith, Joey Sparaga, Hannah Strehlau, Dora Strunk, Larissa Strunk, Lonny Strunk, Larry Strunk, Robbie Strunk, Sandra Toloczko, Richard Vanderhoek, the Qanirtuuq Incorporated Board, the Quinhagak Dance Group and the staff at Kuinerrarmiut Elitnaurviat. We also extend our thanks to three anonymous reviewers for their valuable comments on our paper.Peer reviewedPublisher PD

Binary and Millisecond Pulsars at the New Millennium

We review the properties and applications of binary and millisecond pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the known pulsar population to over 1300. There are now 56 binary and millisecond pulsars in the Galactic disk and a further 47 in globular clusters. This review is concerned primarily with the results and spin-offs from these surveys which are of particular interest to the relativity community.Comment: 59 pages, 26 figures, 5 tables. Accepted for publication in Living Reviews in Relativity (http://www.livingreviews.org

Use of Networking Apps and Knowledge Sharing among Librarians in University of Port Harcourt

The study investigated the use of networking applications for knowledge sharing among librarians in University of Port Harcourt, Rivers State. The purpose was to identify the types of networking apps used, the extent of use, perceived benefits, and problems associated with the use of networking apps for knowledge sharing. The study adopted a descriptive survey design. The population comprised the total of 25 librarians (both practicing & teaching staff). Structured Questionnaire was used as primary instrument for data collection. Data collected was analysed using descriptive statistics of arithmetic mean and standard deviation. The study however identifies email apps, whatsapp, facebook app, instagram app, zoom app, and tweeter app as the types of networking apps used for knowledge sharing, but only few persons used linkedin app and skype app. The study also shows that email apps, whatsapp, facebook app, instagram app and tweeter app were used frequently due to some identified benefits to include ease of use, cost effectiveness, speed of access and retrieval, automatic storage and preservation, external and internal communication and collaboration amongst others. In spite of these overwhelming benefits, high cost of networking devices/subscription, lack of interest, lack of skills, inadequate internet access, fear of criticism and others still militate against the use of networking apps for knowledge sharing among librarians. The study thus recommends adequate capacity building on the use of emerging networking applications for knowledge sharing for all librarians to keep pace with new media. Also, the culture, enthusiasm and the willingness to share knowledge using networking apps should be developed among librarians

The road to the ideal stent: A review of stent design optimisation methods, findings, and opportunities

Coronary stent designs have undergone significant transformations in geometry, materials, and drug elution coatings, contributing to the continuous improvement of stenting success over recent decades. However, the increasing use of percutaneous coronary intervention techniques on complex coronary artery disease anatomy continues to be a challenge and pushes the boundary to improve stent designs. Design optimisation techniques especially are a unique set of tools used to assess and balance competing design objectives, thus unlocking the capacity to maximise the performance of stents. This review provides a brief history of metallic and bioresorbable stent design evolution, before exploring the latest developments in performance metrics and design optimisation techniques in detail. This includes insights on different contemporary stent designs, structural and haemodynamic performance metrics, shape and topology representation, and optimisation along with the use of surrogates to deal with the underlying computationally expensive nature of the problem. Finally, an exploration of current key gaps and future possibilities is provided that includes hybrid optimisation of clinically relevant metrics, non-geometric variables such as material properties, and the possibility of personalised stenting devices