Sample positioning in neutron diffraction experiments using a multi-material fiducial marker

An alternative sample positioning method is reported for use in conjunction with sample positioning and experiment planning software systems deployed on some neutron diffraction strain scanners. In this approach, the spherical fiducial markers and location trackers used with optical metrology hardware are replaced with a specifically designed multi-material fiducial marker that requires one diffraction measurement. In a blind setting, the marker position can be determined within an accuracy of ±164 µm with respect to the instrument gauge volume. The scheme is based on a pre-determined relationship that links the diffracted peak intensity to the absolute positioning of the fiducial marker with respect to the instrument gauge volume. Two methods for establishing the linking relationship are presented, respectively based on fitting multi-dimensional quadratic functions and a cross-correlation artificial neural network

Lipoprotein metabolism and its derangements

No Abstract

Monetêre beheer oor die probleem van inflasie*

Gedurende 1965 is ons ekonomie gekenmerk deur: a) ’n Skerp styging in invoere, soos weerspieël in die feit dat gedurende die eerste sewe maande van 1965 invoere Rl,055 miljoen bedra het vergeleke met R856.8 miljoen die ooreenstemmende tydperk verlede jaar — ’n styging van byna R200 miljoen. In die afwesigheid van beperkende invoerbe- heermaatreëls sou invoere gedurende 1965 in totaal waarskyn- lik die ontsettende syfer van byna R2.000 miljoen bereik het. b) Ten tweede is ons ekonomie gekenmerk deur ’n da­ ting in uitvoere. Die uitvoer van goedere (goud en her-uitvoere uitgesluit) het in die eerste sewe maande van 1965 slegs R537.5 miljoen bedra vergeleke met R559.2 miljoen in die ooreen­ stemmende tydperk verlede jaar — ’n daling van ongeveer R22 miljoen. Dié daling kan hoofsaaklik toegeskryf word aan die volgende faktore: (i) Die droogte-toestande oor wye dele van ons land. (ii) Dalende pryse vir grondstowwe op wêreldmarkte; en (iii) Maklike en winsgewende afset vir plaaslike nywerheids- produkte op die tuismark wat veroorsaak het dat daar by te veel nyweraars ’n mate van traagheid ontstaan het om die moeiliker en meer mededingende buite- landse markte te betree of uit te bou

Job satisfaction of South African registered dietitians

Objectives: The aim of this study was to determine the overall level of job satisfaction among South African registered dietitians and possiblerelationships between the influencing factors.Design: The design was a cross-sectional descriptive study.Setting and subjects: A national survey was carried out among all dietitians registered with the Health Professions Council of South Africa,excluding community service dietitians.Outcome measures: A two-part, self-administered, adapted job satisfaction survey questionnaire was used. Demographic data were collected. The questionnaire covered nine themes pertaining to job satisfaction: salary, promotion, knowledge and skills, professional colleagues, being a member of the multidisciplinary team, communication, the work environment, rewards of the job and nature of the work.Results: A final response rate of 22.5% (n = 340) was obtained. South African registered dietitians were only slightly satisfied (65.7%) withtheir current employment. There was no significant difference (p-value = 0.291) pertaining to overall job satisfaction between those workingand living overseas and those working and living in South Africa. Primarily, lower levels of satisfaction were observed to be due to poor salaries,lack of promotion opportunities and a poor perception of professional image. Significant positive correlations were found between age (p-value= 0.036), professional experience (p-value = 0.035), area of expertise (p-value = 0.001), hours of work (p-value = 0.021) and location of work(p-value = 0.00001).Conclusion: Although overall job satisfaction scores indicated that South African registered dietitians are only slightly satisfied with their employment, registered dietitians reported that they love the nature of the work and what they do, tending towards confirmation of career satisfaction. Recommendations include re-evaluation of registered dietitian salary scales, career pathing with promotion opportunities, boosting the professional image and expanding the teaching of nondietetic skills to dietetic undergraduates

A personalised medicine approach for ponatinib-resistant chronic myeloid leukaemia.

BACKGROUND: Chronic myeloid leukaemia (CML) is characterised by the presence of a fusion driver oncogene, BCR-ABL1, which is a constitutive tyrosine kinase. Tyrosine kinase inhibitors (TKIs) are the central treatment strategy for CML patients and have significantly improved survival rates, but the T315I mutation in the kinase domain of BCR-ABL1 confers resistance to all clinically approved TKIs, except ponatinib. However, compound mutations can mediate resistance even to ponatinib and remain a clinical challenge in CML therapy. Here, we investigated a ponatinib-resistant CML patient through whole-genome sequencing (WGS) to identify the cause of resistance and to find alternative therapeutic targets. PATIENTS AND METHODS: We carried out WGS on a ponatinib-resistant CML patient and demonstrated an effective combination therapy against the primary CML cells derived from this patient in vitro. RESULTS: Our findings demonstrate the emergence of compound mutations in the BCR-ABL1 kinase domain following ponatinib treatment, and chromosomal structural variation data predicted amplification of BCL2. The primary CD34(+) CML cells from this patient showed increased sensitivity to the combination of ponatinib and ABT-263, a BCL2 inhibitor with a negligible effect against the normal CD34(+) cells. CONCLUSION: Our results show the potential of personalised medicine approaches in TKI-resistant CML patients and provide a strategy that could improve clinical outcomes for these patients

Cardiovascular Risk Factors Among People being Treated for HIV in Nepal: a Cross-Sectional Study.

Background: Human Immunodeficiency Virus (HIV) and antiretroviral therapy (ART) are found to be strongly associated with cardiovascular diseases. Data are sparse on the prevalence and distribution of cardiovascular risk factors among people being treated for HIV in South Asia region. Methods: A cross-sectional study of 103 HIV patients (51 women and 52 men) attending routine follow-up consultations at the largest ART centre in Nepal was conducted. Data on several cardiovascular risk factors were collected through interview questionnaires, biophysical measurements and consulting medical records. Results: The most common cardiovascular risk factors observed were central obesity [34.6%, 95% Confidence Interval (CI): 25.3% to 43.9%], chronic kidney disease [20.7% (95% CI: 11.6% to 29.7%)] and tachycardia [20.6% (95% CI: 12.7% to 28.5%)]. Females were significantly more likely to have central obesity (male 9.8% vs. female 60%, p=0.016) and chronic kidney disease (male 15.4% vs. female 26.3%, p=0.003) as compared to the males. Participants were fairly active but a large proportion, especially men, had smoked [65% (95% CI: 57%-72.3%)], used tobacco products [66% (95% CI: 56.4%-74.4%)] or drugs (53.8% of the men) and consumed alcohol [60.2% (95% CI: 50.5%-69.1%)]. Conclusion: A high prevalence of several cardiovascular risk factors was observed among patients being treated for HIV in Nepal. Further larger studies are warranted to better understand the relevance and public health impact of cardiovascular risk factors in this region

Small and micro enterprises – aspects of knowledge, attitudes and practices of managers\' and food handlers\' knowledge of food safety in the proximity of Tygerberg Academic Hospital, Western Cape

Objective. This study determined hazard analysis and critical control point (HACCP) awareness among managers of food-producing small and micro enterprises (SMEs) as well as selected aspects of the knowledge, attitude and practices of respective food handlers regarding food safety. Setting. SMEs within a 30 km range of Tygerberg Academic Hospital. Methods. SMEs were divided into two categories: those providing food to clients at risk of illness (N = 64) and to clients free of illness (N = 81). SMEs were randomly selected and managers/employees completed validated questionnaires regarding HACCP (145 managers) and food safety (159 food handlers). Results. Only 6% of managers reported awareness of HACCP being mandatory in South Africa. More than 70% of managers and food handlers had received no formal training regarding food safety. The perception that food safety control should focus on general cleanliness still prevailed among 57.2% of managers. Food handlers achieved an unsatisfactory score (46.0%) on the basic principles of food safety. Ignorance among food handlers regarding important risk factors was as follows: ways of identifying contaminated food likely to cause food poisoning (77.5%), period of keeping prepared food safe (50.9%), correct way of cooling food (63.1%) or reheating food (84.9%), reason for checking date codes (68.1%) and use of a thermometer (90.6%). There was no significant difference in the results obtained between food handlers in SMEs providing food to healthy clients or clients at risk of illness. Conclusion. Creating awareness and understanding of HACCP among managers of SMEs and education regarding the control of risk factors remain crucial.South African Journal Clinical Nutrition Vol. 20 (2) 2007: pp. 50-6

Familial Hypercholesterolaemia: The Cape Town Experience

Familial hypercholesterolaemia (FH), an autosomal dominantly inherited disorder characterised by elevated plasma low-density lipoprotein (LDL) cholesterol levels, tendon xanthomata and premature ischaemic heart disease, is amenable to treatment with modern medication. The clinical and biochemical details of 1 031 patients with FH were analysed. FH is the most common monogenic disorder of lipoprotein metabolism presenting to the Lipid Clinic at Groote Schuur Hospital, accounting for about 20% of consultations. The hospital classified 55% of the FH patients as white, 43% as coloured, 1.5% as Asian and 0.5% as black. In the FH cohort (whose mean age at presentation was 44 years), 80% had tendon xanthomata, 36% had arcus cornealis, and 14% had xanthelasma. Tendon xanthomata was present in almost 90% of patients by the age of 50 years. Arcus cornealis was present in about 45% by the age of 40 years, further increasing in frequency with age. Cardiovascular complications included ischaemic heart disease (43%), stroke (1.5%), transient ischaemic attacks (1.3%), and peripheral vascular disease (3.7%). The mean age of death was 55 (±13) years; 51 (±10) years in men and 61 (±12) years in women. In 46% of the cohort, a defective gene was identified by testing for locally prevalent mutations.South African Medical Journal Vol. 98 (2) 2008: pp. 99-10

Food insecurity, a perceived barrier to healthy eating in the Lake Victoria Region, Kenya: Findings from a qualitative study

Consumption of poor-quality diets was noted as prevalent in the Lake Victoria Region, Kenya. As a strategy to communicate desirable change and promote healthy eating in the region, a 30-member panel of policymakers and implementers developed and proposed 12 food-based dietary guidelines (FBDGs) in 2017-2018. The objective of this study was to assess barriers in adopting the proposed FBDGs amongst community members in the lowlands of Kisumu and Homa Bay counties. Qualitative, descriptive cross-sectional design was used to collect data from 72 focus-group discussions (FGD). The FGD was conducted among 216 school going children (10-13y), 216 high school students (15-18y), 207 adult males (26-74y) and 211 females (18-71y). The participants were asked to state whether the proposed FBDGs reflected their daily dietary practices? If the answer was no, the FGD participants were asked to elaborate on the perceived barriers. Each FGD consisted of 8-12 participants. The demographics of FGD participants were collected before the start of FGD sessions. All FGD proceedings were audio-recorded and transcribed verbatim. Demographic information of participants was analyzed and presented using descriptive statistics. The FGD responses were coded and analyzed based on the main code, the barriers. Barriers to healthy eating in the study area were mainly linked to low production of food, food unavailability and inaccessibility. Specific factors which contributed to the food insecurity situation included; dry and sunny weather, seasonality in food availability, limited resources to secure potential farmland with fences, gender influence on land use, high cost of food, lack of money to purchase food, low income, sale of farm produce with resultant inadequate quantities of food consumed and inappropriate meal composition. Food insecurity was a perceived barrier to healthy eating in the lowlands of the Lake Victoria region. This research suggests the need to address food systems and economic structures to improve food production, distribution, accessibility and consumption in the region. Coding was done with the aid of NVivo8 (QSR International Pty Ltd Version 8, 2008). This study was registered with the Kenyan National Commission for Science Technology and Innovation (NACOSTI/P/18/12634/22291).&nbsp

Filtered Iterative Denoising for Linear Inverse Problems

Iterative denoising algorithms (IDAs) have been tremendously successful in a range of linear inverse problems arising in signal and image processing. The classic instance of this is the famous Iterative Soft-Thresholding Algorithm (ISTA), based on soft-thresholding of wavelet coefficients. More modern approaches to IDAs replace soft-thresholding with a black-box denoiser, such as BM3D or a learned deep neural network denoiser. These are often referred to as ``plug-and-play" (PnP) methods because, in principle, an off-the-shelf denoiser can be used for a variety of different inverse problems. The problem with PnP methods is that they may not provide the best solutions to a specific linear inverse problem; better solutions can often be obtained by a denoiser that is customized to the problem domain. A problem-specific denoiser, however, requires expensive re-engineering or re-learning which eliminates the simplicity and ease that makes PnP methods attractive in the first place. This paper proposes a new IDA that allows one to use a general, black-box denoiser more effectively via a simple linear filtering modification to the usual gradient update steps that accounts for the specific linear inverse problem. The proposed Filtered IDA (FIDA) is mathematically derived from the classical ISTA and wavelet denoising viewpoint. We show experimentally that FIDA can produce superior results compared to existing IDA methods with BM3D