Observation of Transient Momentum-Space Interference During Scattering of a Condensate From an Optical Barrier

Scattering theory traditionally deals with the asymptotic behaviour of a system far removed from the actual scattering event. Here we present an experimental study of the one-dimensional scattering of a non-interacting condensate of 87-Rb atoms from a potential barrier in the non-asymptotic regime, for which the collision dynamics are still ongoing. We show that for near-transparent barriers, there are two distinct transient scattering effects that arise and dramatically change the momentum distribution during the collision: a deceleration of wavepacket components in mid-collision, and an interference between incident and transmitted portions of the wavepacket. Both effects lead to the re-distribution of momenta giving rise to a rich interference pattern that can be used to perform reconstruction of the single-particle phase profile

Single-atom-resolved probing of lattice gases in momentum space

Measuring the full distribution of individual particles is of fundamental importance to characterize many-body quantum systems through correlation functions at any order. Here we demonstrate the possibility to reconstruct the momentum-space distribution of three-dimensional interacting lattice gases atom-by-atom. This is achieved by detecting individual metastable Helium atoms in the far-field regime of expansion, when released from an optical lattice. We benchmark our technique with Quantum Monte-Carlo calculations, demonstrating the ability to resolve momentum distributions of superfluids occupying $10^5$ lattice sites. It permits a direct measure of the condensed fraction across phase transitions, as we illustrate on the superfluid-to-normal transition. Our single-atom-resolved approach opens a new route to investigate interacting lattice gases through momentum correlations.Comment: 7 pages, 5 figure

Three-dimensional laser cooling at the Doppler limit

Many predictions of Doppler cooling theory of two-level atoms have never been verified in a three-dimensional geometry, including the celebrated minimum achievable temperature $\hbar \Gamma/2 k_B$, where $\Gamma$ is the transition linewidth. Here, we show that, despite their degenerate level structure, we can use Helium-4 atoms to achieve a situation in which these predictions can be verified. We make measurements of atomic temperatures, magneto-optical trap sizes, and the sensitivity of optical molasses to a power imbalance in the laser beams, finding excellent agreement with the Doppler theory. We show that the special properties of Helium, particularly its small mass and narrow transition linewidth, prevent effective sub-Doppler cooling with red-detuned optical molasses.Comment: 8 pages, 5 figure

Observing the Onset of Effective Mass

The response of a particle in a periodic potential to an applied force is commonly described by an effective mass which accounts for the detailed interaction between the particle and the surrounding potential. Using a Bose-Einstein condensate of 87-Rb atoms initially in the ground band of an optical lattice, we experimentally show that the initial response of a particle to an applied force is in fact characterized by the bare mass. Subsequently, the particle response undergoes rapid oscillations and only over timescales long compared to that of the interband dynamics is the effective mass observed to be an appropriate description

Chronic oedema: a prevalent health care problem for UK health services

Chronic oedema is a major clinical problem worldwide, which has many important secondary consequences for health, activity and participation. Effective treatment planning and organisation of services is dependent on an understanding of the condition and its epidemiology. This cross sectional study was designed to estimate the point prevalence of chronic oedema within the health services of one UK urban population and to determine the proportions that have concurrent leg ulceration. Patients with chronic oedema were ascertained by health care professionals in one acute and one community hospital, all relevant out-patient and community nursing services, general practices and all nursing/residential homes in one urban catchment area (Derby City). The presence and distribution of oedema was confirmed through a brief clinical examination. A battery of demographic and clinical details was recorded for each case. Within the study population of Derby City residents, 971 patients were identified with chronic oedema (estimated crude prevalence 3.93 per 1,000, 95% CI 3.69-4.19). The prevalence was highest amongst those aged 85 or above (28.75 per 1,000) and was higher amongst women (5.37 per 1,000) than men (2.48 per 1,000). The prevalence amongst hospital in-patients was 28.5%. Only 5 (3%) patients in the community population had oedema related to cancer or cancer treatment. Of the 304 patients identified with oedema from the Derby hospitals or community health services 121 (40%) had a concurrent leg ulcer. Prevalence statistics and current demographic trends indicate that chronic oedema is a major and growing health care problem

How effective are international framework agreements in subsidiary companies of multinational enterprises? A case study of the international framework agreement of Anglogold Ashanti, Ghana

This paper investigates issues relating to the two International Framework Agreements (IFA) of 2002 and 2009 of AngloGold Ashanti (AGA). IFAs have emerged as a necessary and innovative instrument of global industrial governance (Hammer, 2005) and the globalisation of business activities, and they influence financial direct investments and multinational corporations. The study investigated the effectiveness of IFA in the operations of AGA, focusing on stakeholders’ awareness/knowledge and appreciation of IFAs and the relevance and functionality of the IFA in the operations of AGA. The study occurred within the theoretical framework of sociology of law/legal sociology, which stipulates that an agreement is effective if it ensures designated effects and shapes social behaviour in a predetermined and socially appropriate manner. The methodology was qualitative with a case study design entailing data from desk research and interviews among selected mining stakeholder groups of national and local unions, AngloGold staff, government agencies, academics/researchers, other professionals and NGOs. The results showed that there was little or no awareness/knowledge of IFAs and, therefore, there was virtually no appreciation of the relevance and appreciation of these global agreements. Although AngloGold was purported to be an IFA signatory in all industrial relations literature as it deals with such framework agreements, there was no functioning IFA at AngloGold. While such agreements within the world of industrial relations are very relevant and functional especially outside Africa, this research has shown that local and national unions should be assisted by their global counterparts to deal with the challenges of international labour standards to make such IFAs very relevant and functional in Africa

Indications for referrals to Chris Hani Baragwanath academic hospital gynaecological outpatients department

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Medicine in the branch of Obstetrics and Gynaecology Johannesburg, October 2015Introduction Chis Hani Baragwanath Academic Hospital (CHBAH) is a tertiary (level 3) hospital located in Soweto, Johannesburg. There is no currently no fully functioning district hospital in Soweto. The CHBAH Gynaecological Outpatients Department (GOPD) is burdened by large numbers of patients with a case mix from all levels of care. Objective To describe the clinical characteristics of patients referred to Chris Hani Baragwanath Academic Hospital Gynaecological Outpatients Department and classify them according to levels of care, to assess the lower level case burden carried by the hospital. Methods A prospective cross sectional study was conducted over one week, and 200 participants were selected from the GOPD queue. The researcher interviewed each participant and studied their records to determine their demographic data, reasons for referral and presenting complaints. Upon the participant being seen by the on duty doctor, a provisional diagnosis was made and the appropriate level of care (clinic, level 1 hospital, level 2 hospital, level 3 hospital) was assigned to each based on predetermined classifications of gynaecological conditions into their most suitable levels of care. Results One hundred and ninety three (96.5%) of the participants were referred, and seven (3.5%) were brought by paramedics in ambulances. The most common reason for referral was lower abdominal pain and or vaginal bleeding in pregnancy (n=60; 30%), and the majority of these patients were treated for miscarriages (n=34; 57%). Twenty-four (12%) required admission to hospital. The bulk of patients were classified as level 1 (n=89; 44.5%), with 51 (25.5%) being level 2 and 50 (25%) being level 3 patients. Ten (5.0%) were considered to be primary healthcare (clinic) patients based on their gynaecological conditions. Conclusion The study found that the referral system around Soweto is in place and utilized appropriately and the majority of patients were referred. The study further found that CHBAH serves largely as a district hospital for the surrounding clinics. A fully functioning district hospital would likely relieve CHBAH of much of its burden of patients in the GOPD.MT201

Investigation of the failure of statistical process control in manufacturing industries in South Africa : case study - Atlantis Diesel Engines

Includes bibliography.This work strives to give an insight into why Statistical Process Control (SPC), a quality management tool, is not yielding desired results in some manufacturing industries such as Atlantis Diesel Engines in the Western Cape. Statistical Process Control is an improvement technique that, when properly used, can improve both the quality and the productivity levels which may subsequently improve the competitiveness of a company. SPC achieves this by highlighting when a process is out of control. This happens at the source and a very early stage. The advantage of this is that in the case of manufacturing, rejects are limited and in some cases prevented depending on the relationship between process capability and specifications. The aim of SPC is to reduce variability of characteristics of a product. Wetherill and Brown (1991) revealed that many organisations regulated the quality of their products with SPC during the Second World War. This gives an idea of how long SPC has been in existence. The widespread use of SPC nearly came to an end in the 1960s. The reason for the abandonment of SPC by leading manufacturing industries in most parts of the world was not clear but the belief was that at that time industries were prospering, with little or no competition. However, in the late 1970s, the Japanese industries took the market by storm by the use of quality management techniques and tools, which were introduced by quality gurus such as Deming, Juran, Crosby and many others. This gave the incentive for organisations that wanted to be world class players in their respective sectors to reconsider exhaustively the use of SPC and its tools. In South Africa, predominantly in the Western Cape, SPC has been reintroduced in many companies over the past eight years. The introduction of SPC in most of the industries has not been a smooth transition as it was based on the misconception that if enough of the "right" improvement activities were carried out, then actual performance improvement would improve. There have been many factors hindering the successful implementation of SPC in manufacturing industries such as ADE. This research aims to identify these factors

Behind the Braille: Exploring Disability Officers’ Support for Students with Visual Impairment in Ghanaian Universities

Students with visual impairments face unique challenges in higher education, particularly in accessing academic content and fully participating in university life. Although Ghanaian universities have made policy-level commitments to inclusion, practical support systems, especially the role of Disability Support Officers, have received limited scholarly attention. This study sought to explore the forms of support that Disability Support provide to students with visual impairments in Ghanaian public universities. This qualitative case study explores how Disability Support Officers facilitate the inclusion of SVIs in two Ghanaian public universities. A census sample of five Disability Support Officers from the University of Education, Winneba, and the University of Cape Coast participated in in-depth semi-structured interviews. Additional data were gathered through document reviews and observations at disability support centres. Thematic analysis guided by Braun and Clarke’s six-phase framework revealed four major themes emerged from the analysis: (1) Transcription Services; conversion of academic materials into Braille and large print and conversion of students brailed work into ink for lecturers; (2) Examination Services; adaptations such as Braille-format exams, extended time, and use of assistive devices; (3) Assistive Technology Support; training students in screen readers and other digital tools; and (4) Orientation and Mobility Training; supporting students to independently navigate campus spaces. Disability Support Officers also provided mentorship, emotional support, and institutional advocacy. Challenges identified included limited assistive technology resources, inconsistent faculty collaboration, and gaps in students' prior ICT training. The study concludes that Disability Support Officers serve as the backbone of inclusive education for students with visual impairment, providing multifaceted support that addresses academic, technological, spatial, and emotional needs. However, their work is often constrained by systemic limitations. Strengthening Disability Support Officers capacity, formalising institutional disability policies, and expanding investment in inclusive infrastructure are essential for advancing equity in Ghanaian higher education

Enhanced Graphical Representation of Data in Web Application (Case Study: Covid-19 in the UK)

This paper describes the analysis, design, and implementation of responsive data representation in the web application that can render data asynchronously to users by making an Application Programming Interface (API) request from a webserver. At the same time, provides high-quality downloadable Scalable Vector Graphics (SVG) images for journals, magazines, and other printed media. For this issue, large-scale data that uses open-source Covid-19 data was used to improve the Covid-19 data visualization and the other improvements that can be done for proper representation of such vital data to the general public. During the development process, qualitative research into data representation with responsive charts and/or Scalable Vector Graphics images file has been conducted in contrast of each other to answer questions like what tools and technologies are often used, what are the alternative tools and technology, when, where, and why developers make use of certain approach to data representation