Amplitude, facility and accuracy of accommodation in a primary school population

Vision screening at an early age in children is important as it can identify aspects in the visual system that may need to be managed to enable a child to function optimally at school.  The National School Vision Screening Programme was discontinued in many provinces of South Africa, often due to a lack of financial resources or adequately trained personnel. This action has resulted in the majority of children not having a visual examination during their school career.  In a few instances where vision screenings are performed, these are usually limited to visual acuity (VA) evaluation alone; an endeavour that may miss many significant visual problems.  The purpose of this article is to highlight the need for vision screening to be conducted in schools and for the screening protocols to include the various accommodative tests. A retrospective analysis of the amplitudes of accommodation, accommodative facility and accuracy of accommodation findingsfrom a primary school vision screening of 264 children between 6 and 13 years was undertaken in this study.  Data was captured and analysed with Microsoft Excel. The ages of the children ranged from 6 to 13 years with a mean of 9.38 years (SD = 1.85).  One hundred and thirty eight (52.3%) were males and 126 (47.7%) females.  A significant number of the children failed the monocular accommodative amplitude tests (24%), binocular accommodative amplitude test (26%), the accommodative facility (30%) and the MEM test (27%).  These results highlight the need for a more comprehensive vision screening exercise rather than VA alone as this approach would have  missed more than a quarter of the children who had other visual problems that could impact on their ability to perform optimally at school

Viewpoint: WHO world mental health surveys international college student initiative: implementation issues in low‐ and middle‐income countries

The university system and students are rapidly growing and changing in low‐ and middle‐income countries (LMICs). This growth can facilitate enhanced national productivity yet it can also bring potential risks to student mental health. The World Mental Health Surveys International College Student (WMH‐ICS) initiative could increase information and support in a relatively low‐cost manner for university students in LMICs—a group that is particularly vulnerable to mental health problems and who live in an environment where few targeted resources may be available. Effective implementation of the WMH‐ICS initiative, however, requires long‐term planning and consideration of the specific challenges present in LMIC settings. Planning as to what types of interventions would be needed and achievable in the next 10 to 15 years and consideration of local issues related to uptake, acceptability, appropriateness, feasibility, fidelity, and sustainability from the very beginning would be needed to ensure that the initiative would be useful in the future

Medical cannabis: What practitioners need to know

The South African (SA) Constitutional Court recently decriminalised the private cultivation, possession and use of cannabis by adults. Cannabis contains varying amounts of the cannabinoids delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), depending on various cultivation factors. No commercial plant-derived cannabis products are currently registered by the SA Health Products Regulatory Authority (SAHPRA) for medical use. Such products are therefore unregulated, but are freely available in SA, and may be of inadequate quality and unverified composition, and not guaranteed to be safe or effective. SAHPRA has to date approved only one synthetic medical cannabis product, dronabinol. Evidence supporting benefit from medical cannabis exists for two drug-resistant childhood forms of epilepsy, Dravet syndrome and Lennox-Gastaut syndrome. Adjuvant therapy with medical cannabis can reduce seizure frequency for Lennox-Gastaut syndrome and Dravet syndrome by 18.8% and 22.8%, respectively, and may be beneficial for other rare forms of epilepsy. There is moderate evidence for chemotherapy-induced nausea and vomiting with the synthetic cannabinoids. Multiple sclerosis-associated spasticity showed a small clinical improvement in self-reported spasticity when a purified form of THC/CBD was added to existing therapy. Currently, low-level or no convincing evidence exists for the use of medical cannabis for chronic pain, sleep and weight disorders, and neuropsychiatric disorders. Cannabis is associated with a greater risk of adverse effects than active and placebo controls, and may be involved in clinically significant drug-drug interactions. The evolving regulatory and legal landscape on the use of medical cannabis will guide prescription and recreational use in the coming years

Perceptions, expectations, apprehensions and realities of graduating South African optometry students (PEAR study, 2006)

The objective of this study was to establish the perceptions, expectations, apprehensions and realities of South Africa optometry students completing their undergraduate studies in 2006. Copies of a questionnaire containing relevant information were distributed to all graduating students at the four Universities offering Optometry. The responses were coded and analyzed. The respondents (N=143), representing 77% of the graduating students included 27.3% males and 72.7% females, aged 20 to 37 years (mean = 23.34 ± 2.75). About a third (32.9%) of the respondents considered opening their own practice as the best way of entering into practice. Also, this mode of practice was considered as providing the greatest fulfilment for their personal (60.8%) and professional (53.8%) goals as well as offering long  term financial security (43.7%). Many (56.6%) have secured employment before graduation. Upon graduation, 43.4% would like to join a franchise.  Many (79.7%) felt that Government was not offering sufficient opportunities for optometrists. The majority, (70.6%) felt that the South African optometry profession is fastly becoming saturated and this was of great concern to many (31.5%). About half, (50.3%) have plans to go overseas to practice and the most common destinations were the UK (36.1%) and Australia (15%).  The mean minimum monthly salary expected as new graduates was between R9 500 and R11 500 in the public and private sectors respectively. On a response scale, the future of optometry in South Africa was scored as 6.59 ± 1.92. Findings in this study may be useful to all stake holders in optometric education in South Africa, as they may reflect the future of the optometry profession in the country

MeerTime - the MeerKAT Key Science Program on Pulsar Timing

The MeerKAT telescope represents an outstanding opportunity for radio pulsar timing science with its unique combination of a large collecting area and aperture efficiency (effective area $\sim$7500 m$^2$), system temperature ($T<20$K), high slew speeds (1-2 deg/s), large bandwidths (770 MHz at 20cm wavelengths), southern hemisphere location (latitude $\sim -30^\circ$) and ability to form up to four sub-arrays. The MeerTime project is a five-year program on the MeerKAT array by an international consortium that will regularly time over 1000 radio pulsars to perform tests of relativistic gravity, search for the gravitational wave signature induced by supermassive black hole binaries in the timing residuals of millisecond pulsars, explore the interiors of neutron stars through a pulsar glitch monitoring programme, explore the origin and evolution of binary pulsars, monitor the swarms of pulsars that inhabit globular clusters and monitor radio magnetars. In addition to these primary programmes, over 1000 pulsars will have their arrival times monitored and the data made immediately public. The MeerTime pulsar backend comprises two server-class machines each of which possess four Graphics Processing Units. Up to four pulsars can be coherently dedispersed simultaneously up to dispersion measures of over 1000 pc cm$^{-3}$. All data will be provided in psrfits format. The MeerTime backend will be capable of producing coherently dedispersed filterbank data for timing multiple pulsars in the cores of globular clusters that is useful for pulsar searches of tied array beams. All MeerTime data will ultimately be made available for public use, and any published results will include the arrival times and profiles used in the results.Comment: 15 pages, MeerKAT Science: On the Pathway to the SKA, 25-27 May, 2016, Stellenbosch, South Africa, available at: https://pos.sissa.it/277/011/pd

The Atacama Cosmology Telescope: A Measurement of the 600< ell <8000 Cosmic Microwave Background Power Spectrum at 148 GHz

We present a measurement of the angular power spectrum of the cosmic microwave background (CMB) radiation observed at 148 GHz. The measurement uses maps with 1.4' angular resolution made with data from the Atacama Cosmology Telescope (ACT). The observations cover 228 square degrees of the southern sky, in a 4.2-degree-wide strip centered on declination 53 degrees South. The CMB at arcminute angular scales is particularly sensitive to the Silk damping scale, to the Sunyaev-Zel'dovich (SZ) effect from galaxy clusters, and to emission by radio sources and dusty galaxies. After masking the 108 brightest point sources in our maps, we estimate the power spectrum between 600 < \ell < 8000 using the adaptive multi-taper method to minimize spectral leakage and maximize use of the full data set. Our absolute calibration is based on observations of Uranus. To verify the calibration and test the fidelity of our map at large angular scales, we cross-correlate the ACT map to the WMAP map and recover the WMAP power spectrum from 250 < ell < 1150. The power beyond the Silk damping tail of the CMB is consistent with models of the emission from point sources. We quantify the contribution of SZ clusters to the power spectrum by fitting to a model normalized at sigma8 = 0.8. We constrain the model's amplitude ASZ < 1.63 (95% CL). If interpreted as a measurement of sigma8, this implies sigma8^SZ < 0.86 (95% CL) given our SZ model. A fit of ACT and WMAP five-year data jointly to a 6-parameter LCDM model plus terms for point sources and the SZ effect is consistent with these results.Comment: 15 pages, 8 figures. Accepted for publication in Ap

Failure to perform assisted deliveries is resulting in an increased neonatal and maternal morbidity and mortality: An expert opinion

The need to perform assisted vaginal delivery (AVD) has been regarded as self-evident. In high-income countries, rates of AVD range between 5% and 20% of all births. In South Africa, the rate of AVD is only 1%. This has resulted in increased neonatal morbidity and mortality due to intrapartum asphyxia, and increased maternal morbidity and mortality due to a rise in second-stage caesarean deliveries. In this article, we address the possible causes leading to a decrease in AVD and propose measures to be taken to increase the rates of AVD and subsequently reduce morbidity and mortality

Shift Symmetry and Inflation in Supergravity

We consider models of inflation in supergravity with a shift symmetry. We focus on models with one moduli and one inflaton field. The presence of this symmetry guarantees the existence of a flat direction for the inflaton field. Mildly breaking the shift symmetry using a superpotential which depends not only on the moduli but also on the inflaton field allows one to lift the inflaton flat direction. Along the inflaton direction, the eta-problem is alleviated. Combining the KKLT mechanism for moduli stabilization and a shift symmetry breaking superpotential of the chaotic inflation type, we find models reminiscent of ``mutated hybrid inflation'' where the inflationary trajectory is curved in the moduli--inflaton plane. We analyze the phenomenology of these models and stress their differences with both chaotic and hybrid inflation.Comment: 29 pages, 13 figure

The Atacama Cosmology Telescope (ACT): Beam Profiles and First SZ Cluster Maps

The Atacama Cosmology Telescope (ACT) is currently observing the cosmic microwave background with arcminute resolution at 148 GHz, 218 GHz, and 277 GHz. In this paper, we present ACT's first results. Data have been analyzed using a maximum-likelihood map-making method which uses B-splines to model and remove the atmospheric signal. It has been used to make high-precision beam maps from which we determine the experiment's window functions. This beam information directly impacts all subsequent analyses of the data. We also used the method to map a sample of galaxy clusters via the Sunyaev-Zel'dovich (SZ) effect, and show five clusters previously detected with X-ray or SZ observations. We provide integrated Compton-y measurements for each cluster. Of particular interest is our detection of the z = 0.44 component of A3128 and our current non-detection of the low-redshift part, providing strong evidence that the further cluster is more massive as suggested by X-ray measurements. This is a compelling example of the redshift-independent mass selection of the SZ effect.Comment: 16 pages, 10 figures. Accepted for publication in ApJS. See Marriage et al. (arXiv:1010.1065) and Menanteau et al. (arXiv:1006.5126) for additional cluster result