Prescribed minimum benefits – quagmire or foundation for social health reform?

No Abstract South African Medical Journal Vol. 97 (6) 2007: pp. 446-45

Identifying sequence variation in cation channel sperm associated genes in Cape mountain zebra (Equus zebra zebra)

The Cape mountain zebra (Equus zebra zebra) has recovered from near extinction over more than eight decades. While their numbers have increased, populations remain isolated with low genetic diversity. With more than 75 new populations being founded and more than 4800 extant animals, conservation management strategies are being implemented to mitigate risk of losses in genetic diversity and reproductive fitness. One objective is to identify reproductive characteristics that may improve population growth. Cation channel sperm (CatSper) genes play an important role in hyperactivation of sperm during fertilization. Mutations in these genes lead to reduced fertility and even infertility. Ten male zebras were sampled from a group that were translocated in 2016 in order to found a new population. Single nucleotide polymorphisms (SNPs) were identified in three of the CatSper genes (1 - 3). Lack of variation was observed in all exons, with only four SNPs being identified in the intronic regions in close proximity to exons 1, 2, 7, 8, and 9 of CatSper 1. These results may contribute to the pre-identification of males for new founder populations to ensure population growth and viability, and may be a useful tool for selection against low-producing individuals

Local Differential Privacy for Federated Learning

Advanced adversarial attacks such as membership inference and model memorization can make federated learning (FL) vulnerable and potentially leak sensitive private data. Local differentially private (LDP) approaches are gaining more popularity due to stronger privacy notions and native support for data distribution compared to other differentially private (DP) solutions. However, DP approaches assume that the FL server (that aggregates the models) is honest (run the FL protocol honestly) or semi-honest (run the FL protocol honestly while also trying to learn as much information as possible). These assumptions make such approaches unrealistic and unreliable for real-world settings. Besides, in real-world industrial environments (e.g., healthcare), the distributed entities (e.g., hospitals) are already composed of locally running machine learning models (this setting is also referred to as the cross-silo setting). Existing approaches do not provide a scalable mechanism for privacy-preserving FL to be utilized under such settings, potentially with untrusted parties. This paper proposes a new local differentially private FL (named LDPFL) protocol for industrial settings. LDPFL can run in industrial settings with untrusted entities while enforcing stronger privacy guarantees than existing approaches. LDPFL shows high FL model performance (up to 98%) under small privacy budgets (e.g., epsilon = 0.5) in comparison to existing methods.Comment: 17 page

Unipolar mania reconsidered evidence from a South African study

OBJECTIVE : There is a lack of studies that examine prevalence and phenomenology of bipolar disorder in Africa. In literature, a unipolar manic course of illness in particular is reported to be rare. The purpose of this study was to investigate and describe the course of illness and clinical features for a cross-section of patients diagnosed with bipolar disorder attending public hospitals in Limpopo Province, South Africa and to determine the rate of a unipolar manic course in this sample of patients. METHOD : This was a descriptive, cross-sectional study of patients presenting with a history of mania between October 2009 and April 2010, to three hospitals in Limpopo Province. A purposeful sample of 103 patients was recruited and interviewed using the Affective Disorders Evaluation. RESULTS : This study confirms that a unipolar manic course is indeed much more common than occurrences suggested in present day literature, with 57% of the study sample ever experiencing manic episodes. Patients presenting with a unipolar manic course of illness, as described in this study, may contribute to the search for an etiologically homogeneous sub-group, which presents a unique phenotype for genetic research and the search for genetic markers in mental illness. With a view to future research, a unipolar manic course therefore needs to be considered as a specifier in diagnostic systems in order to increase the awareness of such a course of illness in bipolar disorder. CONCLUSION : Fifty seven percent (57%) of study subjects had only ever experienced manic episodes, which is in keeping with findings from Africa and other non-Western countries. Identifying etiologically homogenous subgroups in psychiatry can also aid the profession in developing a reliable and valid nosology for psychiatric disorders. We need to consider a unipolar manic course at least a specifier in DSM and ICD.http://ajop.co.zaam201

Factors associated with long hospitalisation for psychotic disorder patients in an acute ward: Tertiary care hospital

Background: The average length of stay is often used to indicate health system efficiency; shorter stays are associated with reduced costs. In South Africa, mental healthcare expenditure is spent on inpatient care. Aim: To identify factors associated with a long stay in an acute psychiatric unit. Setting: A tertiary hospital. Methods: A case-control study review of inpatients diagnosed with psychotic symptoms was used. Sample was divided into two groups, length of stay (LOS) (LOS greater than 21 days, LOS less than 14 days). Total of 82 patients were divided into short stay group (SSG, n = 23) and long stay group (LSG) (n = 59). A comparison of demographic, clinical and system variables was conducted. Results: In demographics, LSG had fewer men compared to SSG (78.3%) and differed statistically from LSG with p = 0.05. Long stay groups were older in comparison to SSG with a p = 0.02. Illicit substance use in LSG was 44.1% and statistically less than SSG (73.91%; p = 0.02). A high proportion of LSG had medical or surgical and psychiatric comorbidities (67.8%) compared to SSG (43.5%) (p = 0.04). A total of 95% patients in SSG had family support. Conclusion: Longer stay was found to be associated with older females with primary psychotic disorders. Comorbidities with less availability of family support were associated with younger males presenting with psychotic symptoms that may be related to illicit substances that respond to rapid stabilisation. Contribution: Active surveillance of medical comorbidities amongst older female patients is necessary for early liaison services to reduce their length of stay

Natural convection enhancement in a porous cavity with Al2O3-Ethylene glycol/water nanofluids

The natural convection heat transfer of a differentially heated cavity filled with porous material and saturated with nanofluid is studied. The nanofluid used in the present study contains 60% Ethylene glycol, 40% DI-water and 30 nm size Al2O3 nanoparticles. The volume concentration of nanofluid used is in the range of 0.05% ⩽ ϕ ⩽ 0.4%. The range of Rayleigh number in the present study is 1.2 × 108 ⩽ Ra ⩽ 4 × 108 for clear cavity and 3 × 103 ⩽ Ra ⩽ 1.3 × 104 for the porous cavity. Viscosity of the nanofluid is also measured at volume concentration of 0.05% and found one available model works for the calculations. In order to explain the heat transfer behaviour of the present system, heat transferred by both clear and porous cavity, heat transfer coefficients of both hot and cold wall, as well as Nusselt number variation with concentrations of nanofluids are presented. It is found that the performance of porous cavity filled with a nanofluid volume concentration of 0.05% is enhanced while the other concentrations of nanofluids deteriorate the performance. At a volume concentration of 0.05%, the heat transfer capability of porous cavity is enhanced to a maximum of 10% compared to the base fluids.http://www.elsevier.com/locate/ijhmt2018-05-31hb2017Mechanical and Aeronautical Engineerin

Evaluacija inovativno digitalno kontroliranog Er:YAG lasera u liječenju leukoplakije - probno istraživanje

The use of lasers for treatment of oral leukoplakia has gained a lot of interest in the past years, however, data on the use of Er:YAG laser are scarce. The aim of this study was to compare the efficacy of Er:YAG laser and 1% topical isotretinoin in the treatment of 27 oral leukoplakia patients. Er:YAG laser (LightWalker AT, Fotona, Slovenia) was used in 27 patients with 27 leukoplakia lesions. Postoperative pain was assessed by use of visual analog scale (VAS), and the impact of laser treatment on the quality of life was assessed by the OHIP-14 questionnaire (Croatian version). Control group consisted of the same 27 patients previously treated with 1% topical isotretionin three times a day during the period of one year. No improvement in the size of leukoplakia lesions was observed after treatment with topical isotretinoin. There were significant differences between men and women according to leukoplakia localization, number of laser sessions and VAS (p<0.05). At follow-up after six months and one year, there was no recurrence of lesions. Er:YAG laser is a successful treatment for oral leukoplakia. Topical isotretionin treatment is unsuccessful in patients with oral leukoplakia.Posljednjih godina postoji veliko zanimanje za upotrebu lasera u liječenju oralne leukoplakije, ali su podatci o upotrebi Er:YAG lasera malobrojni. Cilj ovoga istraživanja bio je usporediti učinak Er:YAG lasera i 1%-tnog topikalnog izotretinoina u liječenju 27 bolesnika s oralnom leukoplakijom. Er:YAG laser (LightWalker AT, Fotona, Slovenia) je korišten u 27 bolesnika s 27 leukoplakičnih lezija. Poslijeoperacijska bol je određena uz pomoć vizualne analogne ljestvice (visual analog scale, VAS), a utjecaj na kvalitetu života mjeren je pomoću upitnika OHIP-14 (hrvatska verzija). Kontrolna skupina se sastojala od istih 27 bolesnika koji su prije toga liječeni 1%-tnim topikalnim izotretioninom tri puta na dan tijekom tri mjeseca. Nije bilo poboljšanja u veličini lezija leukoplakije nakon topikalno primijenjenog izotretinoina. Utvrđene su značajne razlike između muškaraca i žena s obzirom na lokalizaciju leukoplakije, broj laserskih zahvata i rezultata VAS (p<0,05). Šest mjeseci i godinu dana od laserskog zahvata nije bilo recidiva oralne leukoplakije. Er:YAG laser je uspješna terapija u liječenju oralne leukoplakije. Topikalna primjena izotretionina nije uspješna u liječenju oralne leukoplakije

The use of dexamethasone in women with preterm premature rupture of membranes - A multicentre, double-blind, placebocontrolled, randomised trial

No Abstract