bluuebunny/crossref_metadata_2025 huggingface dataset:
Optometry in Ethiopia
Authors: Carlson A. S.
Published: October 2016

No abstract available
Conjunctival impression cytology: a review
Authors: Gillan W. D. H.
Published: October 2016

No abstract available
CLINICAL PHOTO-ATLAS Subconjunctival Haemorrhage (SCH)
Authors: Rubin A.
Published: October 2016

No abstract available
Oculo-visual status of the welders in the Capricorn District of the Limpopo Province of South Africa*
Authors: Sithole H. L. , Oduntan O. A. , Oriowo M. O.
Published: October 2016

The process of welding can lead to several ocular disorders when adequate protective precautions are not taken. There is a possibility that welders in the Limpopo Province of South Africa are not taking adequate precautions due to lack of knowledge on the adverse effects of welding. Good vision is also important for effective and injury-free welding.  This study therefore screened welders in the Capricorn district of the Limpopo Province for oculo-visual disorders.  Case history established visual symptoms among the welders and ophthalmic tests such as visual acuity (VA) measurement, pinhole, ophthalmoscopy, external assessment of the adnexa and Amsler grid were used to determine their oculo-visual status.  One hundred and fifty welders were included in the study and their ages ranged from 18 to 65 years with a mean of 39 ± 14.9 years.   Reduced distance vision was reported by 32% of the welders, 14% reported reduced vision at near; 43% reported double vision and 11% reported colour vision anomaly.   Forty seven percent of the welders had VA less than 6/6 at distanceand 8% could only read 1M or larger print at near Following the pinhole test, there was no improvement in 7% of the welders who had VA less than 6/6, indicating a possibility of pathological conditions. Amsler grid showed that 6% of the welders had possible macular disorders. Ophthalmoscopy and external observations revealed that 7% of the welders had cup disc ratio (H/V) of more than 0.6/0.5, Fourteen percentage (14%) had pterygia and 5% had pinguecula.  The study established that although many of the welders had normal oculo visual status, there were a few with ocular disorders which warrant further assessment and managemenby eye care professionals.
Short-term variation of central corneal thickness and axial anterior chamber depth of healthy eyes using Scheimpflug photography via the Oculus Pentacam*
Authors: Mathebula S. D.
Published: October 2016

The purpose of this study was to investigate short-term variation and intra-subject repeatabil-ity of  human central corneal thickness (CCT) and axial anterior chamber depth (AACD) measure-ments obtained using the Oculus Pentacam. Forty consecutive images of the right eye of the anteriorsegment of 10 young and healthy individuals were measured with the Pentacam. Measurements of CCT and AACD were ob-tained from these images and means, standard deviations,variances and repeatability of the measurements were investigated. Both parameters (CCTand AACD) showed small variation with good orexcellent repeatability for all eyes. The inter-subject or overall means and standard deviations for CCT and AACD of the 10 right eyes were 0.555 ±0.05 millimeters (or 555 ± 50 microns) and 3.206± 0.04 millimeters, respectively. The individual or intra-subject averages for samples of CCT and AACD measurements are also provided in this paper. Univariate normality of the data was explored with Kolmogorov-Smirnov, Lilliefors and ShapiroWilks tests and we found that generally the data was normally distributed although there were some exceptions. Based on the results of this study, the Oculus Pentacam appears to provide repeatable and reliable measures for both CCT and AACD in young,normal eyes. Further research is, however, needed to determine short-term variation and repeatability of CCT and AACD with the Pentacam in more com-plicated eyes with, say, corneal scarring or ectasia or where refractive surgery may be an issue.
South African university student knowledge of eye protection against sunlight
Authors: Oduntan O. A. , Carelson A. , Clarke-Farr P. , Hansraj R.
Published: October 2016

Exposure to sunlight has been associated with several ocular conditions such as cataract, age-related macular degeneration, and conjunctival neoplasm. Knowledge of protective modalities and good behavioural practice involving eye protection is essential to prevent adverse effects of sunlight. The purpose of this study was to establish knowledge amongst randomly selected university students in South Africa, of prevention modalities against the adverse effects of sunlight. A questionnaire relating to the knowledge of preventive modalities was completed by randomly selected students from four universities selected by convenience sampling.  Questionnaires completed by one thousand, eighthundred and thirty two (N =1832) subjects were analysed with descriptive statistics using Stata version 10.  The participants’ ages ranged from 17 to 55 years (mean = 21.03 ± 3.4 years).  They included 43.7% males and 56.3% females.  They were 68.3% Blacks, 20.0% Whites, 3.4% Indians and 7.4% Coloureds. Many (82.3%) of them knew that excessive exposure to sunlight can adversely affect the eyes. Only 28.5% reported that they often wore sunglasses outdoors. Only 38.5% of the participants knew that not all spectacles or contact lenses could protect eyes from ultraviolet radiation. However, many, 87.7% and 69.5% respectively knew that sunglasses and spectacles could be specifically designed to block UVR from entering the eye. Just over half (52.7%) knew that contact lenses can be specifically designed to block the UVR. Many, (68.4%) agreed that wearing hats with brims could protect the eyes against harmful radiation from the sun and the majority, 95.8% agreed that there was a need for awareness campaigns about the effects of the sun on the eye and against excessive exposure. Female respondents had more knowledge of preventive modalities than the males.  Knowledge of preventive modalities among the respondents varied significantly with the type of questions and was poor for certain questions. This suggests a need for an eye protection awareness campaign amongst the general population in South Africa, about the possible adverse effects of sunlight on the eye and appropriate protective practices.
The effects of visual skills on Rhythmic Gymnastics*
Authors: Potgieter K. , Ferreira J. T.
Published: October 2016

Vision plays an important role in all sports, but has often been neglected when evaluating the performance of athletes. Rhythmic Gymnastics is a dynamic and compelling sport for girls that challenge body and mind. It is a relatively new Olympic sport that requires performance according to a set standard. The goals of this study were to identify the visual skills important to rhythmic gymnasts and to explore whether these skills could be improved by means of an intervention programme. This study further aims to provide sport specific visual performance standards to the gymnasts. Little research is available connecting vision to this sport and it was seen as a good opportunity to make a difference. After testing the visual skills of a sample of 62 rhythmic gymnasts (divided randomly into two comparable groups of 32 for the experimental group and 30 for control group) the experimental groupfollowed a sports specific intervention programme while the control group adhered to their regular training schedule.  The visual skills trained by the intervention programme were re-tested on both the experimental and control groups of gymnasts. The results obtained from the post-intervention meas-urements were analyzed and compared to the original data obtained from the pre-intervention measurements of both the groups of gymnasts. Results from competitions were obtained and compared to establish the effect of the intervention programme. It is concluded that the software skills of the visual system plays an important role in the sport of rhythmic gymnastics. These skills can be improved by implementing a sustainable visual training programme for the training of rhythmic gymnasts.
A pilot study on vision related quality of life determined using the NEI RQL-42 questionnaire
Authors: Gillan W. D. H.
Published: October 2016

No abstract available
General approach to the sensitivity of the optics of an eye to change in elementary parameters with application to the Gaussian optics of a reduced eye
Authors: Harris W. F.
Published: October 2016

Optical properties of the eye, including the refractive compensation, for example, may change if there are changes in any of the components that make up the eye.  The sensitivity to such changes isquantified via the derivative.  This paper employs the reduced eye and Gaussian optics to illustrate a general method for the analysis of sensitivity in eyes.  The method requires a clear statement of the dependent variable as a function of independent variables.  A symbolism is offered that makes the function unambiguous.  Sensitivities are determined for the fundamental optical properties,the transference and the corneal-plane refractivecompensation of a reduced eye to change in corneal power, curvature and radius of curvature and to change in axial length and index of refraction.  Emsley’s reduced eye is examined in particular.  Its corneal-plane refractive compensation has a sensitivity of  135 −135 D to change in refractive index,  1 −2.7 D/mm to change in length and  135 −1/3 to change in corneal curvature when the other two independent variables are held fixed.  The method has the potential to develop guidelines that are useful clini-cally.
Current practices of diagnostic techniques requir- ing the use of ophthalmic drugs among KwaZulu- Natal optometrists*
Authors: Mashige K. P. , Naidoo K. S.
Published: October 2016

In anendeavour to improve the quality of optometric eye care services in South Africa, the scope of practice was expanded to include the use of ocular diagnostic procedures such as goniosco-py that require the use of ophthalmic drugs. The purpose of this study was to assess the practices of specific diagnostic techniques (contact tonometry, 78 D/90 D lens fundus examination, binocular indirect ophthalmoscopy and gonioscopy) requiring the use of ophthalmic drugs among optometrists in KwaZulu-Natal (KZN) province. These specific techniques are referred to as diagnostic procedures in this article. A questionnaire containing information on demography and practice of these specific techniques was sent to all 213 KwaZulu-Natal registered optometrists who owned private practices. One hundred and thirty two completed questionnaires were received, a response rate of 62%. One hundred and seventeen (55%) of the questionnaires were included in the analysis of which 55% of the respondents were females and 45% were males. Sixty two optometrists (53%) were certified in di-agnostic procedures but many procedures were not being practiced. These procedures and the percentage respondents were: Contact tonometry (60%), 78 D/90 D lens fundus examination (60%), binocular indirect ophthalmoscopy (84%) and gonioscopy (78%). Also, among these certified respondents (62 optometrists), a significant proportion (60%) disagreed when asked if they were confident and proficient in performing the relevant diagnostic procedures. Many, (61%) agreed that lack of incentives discouraged them from routinely performing the procedures. More than half (58%), agreed that chair time was an important factor in deciding whether or not to perform these diagnostic procedures. Of the total respondents (117), 86% agreed that they were confident about the accuracy of their referrals and less than half (45%) disagreed that diagnostic procedures should be the sole responsibility of ophthalmologists. Less than half (48%) agreed that diagnostic procedures should be incorporated into routine eye examinations. This study indicatesthat the performance of these diagnostic procedures was limited despite many optometrists having the  necessary educational certification. It is recom-mended that initiatives that can be translated into practical action such as CPD workshops should pay greater attention to the improvement of diagnosticskills and practice. In addition, further education or opportunities emphasizing the importance of per-forming these diagnostic procedures over financialgains and time constraints are warranted.
Ethical issues in optometric practice
Authors: Sithole H. L.
Published: October 2016

Ethics as a discipline is the study and analysis of values and standards related to duty, responsibility, and right and wrong behavior. The ethical obligations of optometry toward patients are similar to those of other health professionals. These obligations generally require optometrists to recognize, respect, and protect the rights of their patients. This approach encourages patients to participate actively in their care and allows them to develop arelationship with their optometrist based on trust. The ethical codes which contain guiding principles serve to help practitioners in their decisions and in practicing in accordance with a set of standards that are expected of a health care practitioner. There are four major ethical principles in health care, namely; beneficence, non-maleficence, and respect for autonomy and justice. Because these principles are easily recognized as being among the primary ethical goals of health care, using them as the basis for ethical analysis may help to explain the moral justification for certain professional actions as well as to identify unethical behavior. However, in clinical practice, the specific demands and rationales of these broad principles may be difficult to apply. This illustrates the paradox that whilst these principles are essential tools for ethical practice, if applied too rigidly, they can be problematic. How-ever, the goal of ethical decision making in optometry should be to identify one or more courses of action that will honor the profession’s essential values while minimizing conflict with other values and professional standards. Every profession, every practice and every practitioner is governed by not only legal constraints, but also by the ethical concerns of ensuring that the patient is properly served. Considering our practices from a patient’s perspective can help optometrists understand the multiple responsibilities of clinical practice. (S Afr Optom 2010 69(2) 93-99)
Generalized magnification in visual optics. Part 2: Magnification as affine transformation
Authors: Harris W. F.
Published: October 2016

In astigmatic systems magnification may be different in different directions.  It may also be accompanied by rotation or reflection.  These changes from object to image are examples of generalized magnification.  They are represented by  2 2×  matrices.  Because they are linear transformations they can be called linear magnifications.  Linear magnifications account for a change in appearance without regard to position.  Mathematical structure suggests a natural further generalization to a magnification that is complete in the sense that it accountsfor change in appearance and position.  It is represented by a  3 3×  matrix with a dummy third row. The transformation is called affine in linear algebra which suggests that these generalized magnifica-tions be called affine magnifications.  The purpose of the paper is to define affine magnification in the context of astigmatic optics.  Several examples are presented and illustrated graphically. (S Afr Optom 2010 69(4) 166-172)
A review of factors influencing the utilization of eye care services
Authors: Ntsoane M. D. , Oduntan O. A.
Published: October 2016

Visual impairment (low vision and blindness) is a major health concern all over the world. Three main reasons for the high prevalence of visual impairment are non-availability, non-accessibility andnon-affordability of eye care services. However, there are several factors that may act as barriers to the use of available, accessible and affordable eye care services. These include the lack of knowledge of the services, lack of knowledge of the possible impact of an eye disease and lack of knowledge of who to consult for management of eye diseases. Also, demographic, personal, social and cultural factors may influence or act as barriers to eye care utilization. These various factors are reviewed in this article. Where there is poor utilization of available services, educational campaigns would lead to better understanding and promote greater utilization of eye care services. Early detection and management of eye diseases would reduce the burden of visual impairment and disability. Therefore, eye care providers and health care managers must have good knowledge of the various factors that would negatively influence utilization of eye care services and be responsive to them. (S Afr Optom 2010 69(4) 182-193)
The relationship between central corneal thickness and corneal curvature in adult Nigerians
Authors: Iyamu E. , Eze N. M.
Published: October 2016

Purpose: The aim of this study was to provide average values for central corneal thickness (CCT) and corneal curvature (CC) and also to determine a regression model for the relationship between CCT and CC in adult Nigerians without glaucoma.Methods: A total of 95 subjects consisting of 56 males and 39 females aged between 20 and 69 years with mean age of 47.1 ± 14.1 years were recruited for the study. Central corneal thickness was measured by ultrasound pachymetry (SW-1000P ultrasound pachymeter, Tianjin Suowei Electronic Technology, China) and corneal curvature was measured by keratometry (Bausch & Lomb keratometer H-135A, USA).Results: The average values of 550.1 ± 33.1µm and 43.0 ± 1.1 D were obtained for CCT and CC respectively. CCT significantly correlated with age (p=0.01), and the regression model predicts a decrease of 6.0 µm in CCT per decade. No significant association was found between CC and age (p=0.56). Also, no significant association was found between CCT and CC (p=0.07). Female subjects had significantly steeper corneas than their male counterparts.Conclusion: Central corneal thickness decreases with increasing age. Neither CCT nor age appear to be significantly correlated with corneal curvature. (S Afr Optom 2011 70(1) 44-50)
Factors influencing South African optometry students in choosing their career and institution of learning
Authors: Mashige K. P. , Oduntan O. A.
Published: October 2016

Thechoice of an appropriate career, occupation or profession is one of the most important decisions hat one makes in life and there are many factors which may influence such a decision. The purpose of this study was to establish the factors which influenced students currently studying optometry in South African institutions in deciding on the course of study and choice of institution. Data was collected with a questionnaire on demographics of the students and the factors that might have influenced their choice of optometry as a career and their institution of learning. Data was analysed with descriptive and cross-tabulation statistics. Three hundred and eighty seven students responded to the questionnaire (80.1% response rate). Their ages ranged from 17 to 40 years with a mean of 20.73 ± 2.46 years and included 30.5% males and 69.5% females. They were from the University of Free State 25.1%), University of Johannesburg (29.5%), University of KwaZulu-Natal (29.7%) and the University of Limpopo(15.7%). There were 38% Whites, 36.7% Blacks, 22.2% Indians and 3.1% Coloureds. The highest rated factors which influenced their choice of optometry were the desire to help other people (92.8%), job availability after graduation (92%), subjects passed and points obtained in the matric year (91.2%) and the potential to earn a good salary (88.6%), respectively. Few rated news and other media (20.9%) as an important factor in their decision to choose their current institution of learning while 29.5% reported that failure to gain admission to study other degrees was an important factor. These results may be useful to institutions offering optometry degrees to formulate effective recruitment strategies to attract quality students. Also, they may be useful to career counsellors in counselling prospective students on their career choice and institution of learning. (S Afr Optom 2011 70(1) 21-28)
Quantitative analysis of the linear optical character of the anterior segment of the eye*
Authors: Mathebula S. D.
Published: October 2016

No abstract available
Chromagen lenses and abnormal colour perception
Authors: Oriowo O. Matthew , Alotaibi Abdullah Z
Published: October 2016

Background: The Chromagen lens system comprises of tinted spectacle or contact lenses, each with a specific colour wavelength filter which controls the spectra of the light entering the eye. This study investigated whether spectacle-mounted Chromagen lenses would enhance colour perception in individuals with abnormal colour vision.Methods: The Ishihara colour test was used to test for colour vision deficiency (CVD) and also to evaluate the effect of the Chromagen spectacle lens on colour perception in 13 subjects. An Oculus Anomaloscope was used to confirm and sub-classify the types of CVD. Subjects comprised of school age children from the Riyadh area in Saudi Arabia.Results: The distribution amongst the male participants comprised two subjects with protanomaly, two with protanopia, five with deuteranomaly, and two with deuteranopia. Amongst the two female participants, one subject showed deuteranomaly, and one showed protanomaly. Different types of Chromagen spectacle lenses displayed some levels of colour vision enhancement depending on type of CVD.Conclusion: The findings support the notion that chromagen lenses could enhance colour vision perception in some cases of red-green colour vision defects. Clients with CVD should be managed on an individual case basis. (S Afr Optom 2011 70(2) 69-74)
The prevalence of strabismus in schizophrenic patients in Durban, KwaZulu Natal
Authors: Ndlovu D. , Nhleko S. , Pillay Y. , Tsiako T. , Yusuf N. , Hansraj R.
Published: October 2016

Purpose:    The psychosocial implications of a strabismus have not received sufficient attention and yet may have a significantly negative effect on a person’s life.  Schizophrenia is the fourth leading cause of mental disability in the developed world.  Both schizophrenia and strabismus appear to share a genetic and neurological origin.  This study thus set out to assess the prevalence of strabismus in a sample of schizophrenic subjects. Setting:  The study was carried out in Durban, Kwazulu-Natal inSouth Africa specifically at the Durban and Coastal Mental Health Institution. Method:  Fifty schizophrenic subjects residing at the Durban and Coastal Mental Health (DMH) Institution were assessedfor the presence of strabismus using the cover test and modified Krimsky test.  The inclusion criteria were all subjects diagnosed with schizophrenia, of both genders and any race.  The subjects werebetween fifteen to seventy years of age.  The exclusion criteria included any other mental illness, systemic disease or medication other than that usedon schizophrenic patients.  Results:   The prevalence of strabismus in this sample was found tobe 74% which was considerably higher than thatreported by other studies1,2.  There was a greater incidence of exotropia as opposed to esotropia.  The mean distance exotropia as detected with the cover test was 33 prism dioptres.  Similarly, the near cover test indicated a mean of 11 prism dioptres exotropia, and with the modified Krimsky test a mean of 9 prism dioptres exotropia.   Most of the strabismic subjects (86.5%) presented with a strabismus when fixating a near target.  Generally the strabismus was found to be constant and unilateral and no gender bias was found.  Conclusion:There appears to be a strong relationship between strabismus and schizophrenia.  Health care professionals, especially those dealing with paediatric care, parents and the public should be made awareof this relationship so that psychological adviceand early intervention can be sought for strabismic children. (S Afr Optom 2011 70(3) 101-108)
Institutional, gender and racial profiles of South African optometrists
Authors: Nirghin U. , Khan N. Ebrahim , Mashige K. P.
Published: October 2016

This paper sets out to profile optometric gradu-ates in South Africa. The 2008 register of the Health Professions Council of South Africa (HPCSA) was used to identify the number of registered optometrists, their qualifications and institutions where they obtained their primary optometry qualification. The gender and racial profiles of these optometrists were obtained from the institutions where they qualified. A comparison of the profiles ofthe registered practitioners pre-democracy (1930-1994) and post-democracy (1995-2008) was made. Few (28.1%) of the optometrists were trained in the years 1930-1994, while the rest (71.9%) were trained from 1995-2008. During the period of1930-1994, 64.2% of the optometrists were males and 35.8% were females and from 1995 to 2008, the gender profile changed to 66.4% females and 33.6% males. In the pre-democracy period (1930-1994), almost three quarters (74%) of the registered optometrists were White, 15.3% were Indians, 7.9% were Black and 2.8% were Coloured. Many (56.9%) that were registered pre-1994 were trained at the Technikon Witwatersrand (TWR), 17.1% were trained at the University of Durban Westville (UDW), 11.9% at the Rand Afrikaans University (RAU), 6.7% at the University of the North (UNIN) and 7.4% had trained in institutions outside South Africa. The percentage of White optometrists post-democracy (1995-2008) decreased to 44.3%, while those of Indians increased to 22%, Blacks increased to 28.9% and Coloured to 4.8%. Almost half (48.2%) of the optometrists in the post-apartheid era (1995-2008) were trained at the University of Johannesburg (UJ), TWR and RAU, 21.5% at UDW and University of KwaZulu-Natal (UKZN), 23.7% at UNIN and the University of Limpopo (UL), 4% at the University of Free State (UFS) and others (2.6%) had trained outside South Africa. As at 2008, the majority (51.7%) of all registered optometrists were White, 22.2% were Black, 21.9% were Indian while 4.2% were Coloured and included 57.8% females and 42.2% males. The results of this study indicate that the number of females in all racial categories has increased post-democracy. Although the number of Black optometrists has increased in the post-democracy era, the increase does not yet reflect the national population distribution. Optometry departments need to improve on the equity targets.(S Afr Optom 2011 70(3) 123-128)
A review of the role of oxidative stress in the pathogenesis of eye diseases
Authors: Oduntan O. A. , Masige K. P.
Published: October 2016

Free radicals, referred to as oxidants are molecules in the body with unpaired electrons, hence are unstable and ready to bond with other molecules with unpaired electrons.  They include Reactive Oxygen Species (ROS) such as superoxide anion radicals (·O¯), hydrogen peroxide (H202), and hydroxyl free radicals (·OH).  Endogenous sources of ROS include metabolic and other organic processes, while exogenous sources include ultraviolet radiation and environmental toxins such as smoke.  Antioxidants (oxidant scavengers) such as ascorbate, alpha-tocopherol and glutathione as well as various enzymatic compounds such as superoxide dismutase (SOD), catalase and glutathione reductase are also present in the body and in manyfoods or food supplements.  An imbalance between oxidants and antioxidants in favour of oxidantsis termed oxidative stress and can lead to cell or tissue damage and aging. Oxidative stress has been implicated in the pathogenesis of many serious systemic diseases such as diabetes, cancer and neurological disorders.  Also, laboratory and epidemiological studies have implicated oxidative stress in the pathogenesis of the majority of common serious eye diseases such as cataract, primary open angle glaucoma and age-related macular degeneration. In this article, we reviewed the current information on the roles of oxidative stress in the pathogenesis of various eye diseases and the probable roles of antioxidants.  Eye care practitioners will find this article useful as it provides information on the pathogenesis of common eye diseases. (S Afr Optom 2011 70(4) 182-190)
Neurobiology of developmental dyslexia: Part 1: A review of evidence from autopsy and structural neuro-imaging studies
Authors: Wajuihian S. O.
Published: October 2016

Developmental dyslexia (DD) is a language-based neurological disorder which impairs readingability but does not result from low intelligence,lack of motivation, sensory impairment, or inadequate instruction. Although the neurological basisof dyslexia has long been assumed, the exact natureof the altered brain structure associated with DD remains unknown and has been a subject of autopsyand neuro-imaging research.  Autopsy studies provide consistent evidence of symmetry of the planum temporale (PT), thalamus and cortical malformations, whereas results from structural imaging studies such as computed tomography (CT) and magnetic resonance imaging (MRI) are inconsistent. To address the possible etiology of DD, this paper reviews evidence from autopsy and structural imaging studies on developmental dyslexia and discusses possible methodological sources of some inconsistent results. The role of the optometrist in the multidisciplinary management of dyslexia is highlighted. (S Afr Optom 2011 70(4) 191-202)
Knowledge of diabetes mellitus in privately- funded diabetic patients attending a rural optometric practice in Malmesbury, South Africa*
Authors: Phillips K. C. , Mashige K. P. , Clarke-Farr P. C.
Published: October 2016

Patient knowledge about diabetes mellitus (DM) and appropriate timely management with respect to the condition are important factors for limiting the complications of the disease. The aim of this study was to evaluate knowledge and practices regarding DM, its ocular effects and management protocols among privately-funded diabetic patients. A questionnaire containing questions on these issues and certain demographics was provided to 73 self-funding or privately-funded diabetic patients attending an optometric practice in a rural district of the Western Cape. Respondents ages ranged from 33 to 80 years (mean = 57 ± 11.2 years) and included 59% males and 41% females. Above half(56%) of the respondents knew that there were two main types of DM. Less than half (46%) of the respondents reported having Type 2 DM, 4% reported having Type 1 DM and 49% did not knowwhat type of DM they had. Although 82% of the respondents reported owning a glucometer and 98% knew that controlling their blood sugar levels may help reduce diabetic complications, only 29% measured their blood sugar levels on a daily basis. Most respondents (97%) agreed that DM could affect their vision yet only 37% stated that they had annual eye examinations. A significant proportion of the respondents did not know that DM could cause strabismus (57%), colour vision problems (44%), cataracts (41%), retinopathy (37%) and contribute to causing glaucoma (63%). Most respondents took their medication regularly and as prescribed (89%) and underwent regular medical check-ups (82%). However, a large proportion of the respondents did not exercise regularly (61%), had no regular eye testing (63%) nor Body Mass Index (BMI) monitoring (84%) in their manage-ment of DM. This study indicates that, despite access to private health care, these subjects level of knowledge of DM and its ocular effects was sub-optimal. It also indicated poor self-management practices of the diabetic patients towards diabetes care and management. Optometrists should form part of a team of health professionals to assist in the management of DM. (S Afr Optom 2012 71(2) 70-77)
Ocular injuries - a review
Authors: Sukati V. N.
Published: October 2016

No abstract available
Benign intracranial hypertension diagnosed with bilateral papilloedema
Authors: Phillips K. C. , Clarke-Farr P. C.
Published: October 2016

This article presents a case of benign intracranial hypertension (BIH) diagnosed from the presence of papilloedema. This potentially sight-threatening condition particularly affects younger obese females and can be idiopathic, caused by adverse reaction to certain prescription medications or by systemic disease. Prompt treatment is essentialto avoid optic atrophy and low energy diet and exercise forms part of long-term treatment to avoid relapse. Optometrists can play a critical primary health care role in the detection of papilloedema and referring appropriately.
Traditional eye medicine practice in Benin-City, Nigeria
Authors: Ebeigbe J. A.
Published: October 2016

The use of traditional eye medicines as a form of eye care in Africa is very common.  However, there is concern about the harmful effects of some traditional medicines on the eyes. This study was a cross-sectional survey conducted in Benin-City, Edo state, Nigeria. Sixty-eight traditional medicine practitioners (TMPs) who treated eye conditions participated in this study.  Most (87%) were males and 13% were females. Their age ranged between 25 to 65 years with a mean age of 42.25 ± 2.14 years.  Information was obtained through one-on-one oral interviews and a structured questionnaire consisting of open-ended questions. The most common method of training (46%) was by father-to-son tutelage. Conjunctivitis, itching and poor vision were the most common conditions treated by all practitioners. The majority of the TMPs (62%), practiced full time while 38% practiced part time. Forty six percent considered patients’ case histories as more important than physical examination of the eye while 54% felt both history and examination were equally important. Thirty-six percent of practitioners reported inverting the upper eyelids as part of their examination. Couching of cataracts was done by 38%. While 49% had referred ‘difficult’ or ‘stubborn’ cases to orthodox hospitals, 51% had never referred a case.  Traditional healers are well accepted in their communities and will continue to be consulted by the people.  Health education programs with emphasis on safe eye care practices need to be established for traditional healers. Working with healers and training them to recognize cases needing urgent referral and encouraging the use of non-harmful practices may provide a more sustainable health care structure in the community. Cooperation between these two aspects of medicine is extremely important for the provision of primary eye care services in rural Africa. (S Afr Optom 2013 72(4) 167-172)
Visual acuity, amplitude of accommodation and near point of convergence and academic achievement in primary school learners in Bloemfontein
Authors: Nel Mariette , Hartley Stephen , Maartens Melissa , Pheiffer Carla , Nonkula Monwabisi , Steyn Anel
Published: October 2016

Introduction: Learning problems influencing the social and psychological development of children may result from poor visual acuity (VA), insufficient amplitude of accommodation and receded near point of convergence (NPC). This study assessed Grade 4 and 5 academic achievement (< 50%, 51-69% and ≥ 70%) in relation to visual acuity, amplitude of accommodation and NPC. The study attempts to determine the association between these visual functions and academic performance. Methods: A cross-sectional study included a randomised sample of learners (n = 199) selected from five public schools in Bloemfontein. Information was obtained on each participant regarding history, visual acuity (distance and near), amplitude of accommodation and NPC (subjective and objective). Participant aggregates for the most recent school term and the grade average were compared to measures of these visual functions.Results: The children’s median age was 10.3 years (with range 8.7 to 12.7 years) and 53.8% were female. More than 50% of children were Sesotho-speaking. Complaints revealed by his-tory-taking were mostly headaches (57.8%) and eyestrain (58.3%). Regarding academic achievement, 18.6% of the learners were below average, 53.8% on average and 27.6% above average. Of the learners tested, 42.2% achieved a VA of 6/6 or better on both distance and near visual acuity. Amplitude of accommodation was less than the minimum requirements in 17.6% of participants. Approximately 30% of those below grade average did not meet the minimum requirements for amplitude of accommodation, compared to 13% of learners above grade average, which was statistically significant. More than 70% had a receded break point (> 5 cm) for NPC and 85.7% had a receded recovery point (> 7 cm).Conclusion: Of the three visual functions evaluated in this study, the only visual function associated with academic achievement was amplitude of accommodation. It would thus be recommended that learners are screened for optimal visual function earlier in life if especially the amplitude of accommodation is receded.
From the Editor’s Desk
Authors: Rubin A.
Published: October 2016

No abstract available.
Association analysis of g.68G  → A SNP in CAPN1 gene with carcass and meat
quality traits in goose raised in organic dehesa
Authors: Solé Marina , Negro Sara , Membrillo Alberto , Peña Francisco , Domenech Valeriano , Verona Juan Carlos , Rubí Maria , Valera Mercedes , Molina Antonio
Published: October 2016

Abstract. Meat quality is an important concern for the poultry industry. Domestic geese products obtained from free-range systems usually have rather tough meat, and it is necessary to select them to improve meat tenderness. The relation of the calpain 1 (CAPN1) gene with the post-mortem tenderness process of meat has been demonstrated in several species. Thus, the objective of the present study was to identify polymorphisms in this gene and to perform an association analysis between these polymorphisms and related economic traits in goose raised in the dehesa ecosystem. For the analysis, 50 geese of 3 different subpopulations (20 Embden Anser anser; 20 Toulouse Anser anser; 10 F1 cross) were studied. The experimental protocols were followed complying with principles of animal welfare. A novel SNP was found in the CAPN1 gene, g.68G → A. This polymorphism was statistically associated with different carcass and meat quality traits such as thigh muscle width (P = 0.020) and the b* 10-day meat colour parameter (P = 0.024) for the global goose population. The association of this gene with meat tenderness (Warner–Bratzler shear force) was confirmed in the case of female individuals of the Toulouse breed (P = 0.043). The results suggest the possibility of using molecular markers in CAPN1 gene as a potential tool for improving carcass and meat quality traits in goose breeding programmes.
Four dimensional variational inversion of black carbon emissions during ARACTAS-CARB with WRFDA-Chem
Authors: Guerrette Jonathan J. , Henze Daven K.
Published: October 2016

Abstract. Biomass burning emissions of atmospheric aerosols, including black carbon, are growing due to increased global drought, and comprise a large source of uncertainty in regional climate and air quality studies. We develop and apply new incremental 4D-Var capabilities in WRFDA-Chem to find optimal spatially and temporally distributed biomass burning (BB) and anthropogenic black carbon (BC) aerosol emissions. The constraints are provided by aircraft BC concentrations from the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites in collaboration with the California Air Resources Board (ARCTAS-CARB) field campaign and surface BC concentrations from the Interagency Monitoring of PROtected Visual Environment (IMPROVE) network on 22, 23, and 24 June, 2008. We consider multiple BB inventories, including Fire INventory from NCAR (FINN) v1.0 and v1.5 and Quick Fire Emissions Database (QFED) v2.4r8. On 22 June, aircraft observations are able to reduce the spread between QFED × ⅓ and FINNv1.0 from ×3.5 to ×2.1. On 23 and 24 June, the spread is reduced from ×3.4 to ×1.4. The posterior corrections to emissions are heterogenous in time and space, and exhibit similar spatial patterns of sign for both inventories. The posterior diurnal BB patterns indicate that multiple daily emission peaks might be warranted in specific regions of California. The U.S. EPA's 2005 National Emissions Inventory (NEI05) is used as the anthropogenic prior. On 23 and 24 June, the coastal California posterior is scaled by × ½, where highway sources dominate, while inland sources are increased near Barstow by ×5. Relative BB emission variances are reduced from the prior by up to 35 % in grid cells close to aircraft flight paths and up to 60 % for fires near surface measurements. Anthropogenic variance reduction is as high as 40 % and is similarly limited to sources close to observations. We find that the 22 June aircraft observations are able to constrain approximately 14 degrees of freedom of signal (DOF), while surface and aircraft observations together on 23/24 June constrain 23 DOF. Improving hourly to daily scale concentration predictions of BC and other aerosols during BB events will require more comprehensive and/or targeted measurements and a more complete accounting of sources of error besides the emissions.
Comparing multiple model-derived aerosol optical properties to collocated ground-based and satellite measurements
Authors: Ocko Ilissa B. , Ginoux Paul A.
Published: October 2016

Abstract. Anthropogenic aerosols are a key factor governing Earth’s climate, and play a central role in human-caused climate change. However, because of aerosols’ complex physical, optical, and dynamical properties, aerosols are one of the most uncertain aspects of climate modeling. Fortunately, aerosol measurement networks over the past few decades have led to the establishment of long-term observations for numerous locations worldwide. Further, the availability of datasets from several different measurement techniques (such as ground-based and satellite instruments) can help scientists increasingly improve modeling efforts. This study explores the value of evaluating several model-simulated aerosol properties with data from collocated instruments. We compare optical depth (total, scattering, and absorption), single scattering albedo, Ångström exponent, and extinction vertical profiles in two prominent global climate models to seasonal observations from collocated instruments (AERONET and CALIOP) at seven polluted and biomass burning regions worldwide. We find that models may accurately reproduce one variable while totally failing at another; data from collocated instruments can reveal underlying aerosol-governing physics; column properties may wash out important vertical distinctions; and "improved" models does not mean all aspects are improved. We conclude that it is important to make use of all available data (parameters and instruments) when evaluating aerosol properties derived by models.
A fifteen year record of CO emissions constrained by MOPITT CO observations
Authors: Jiang Zhe , Worden John R. , Worden Helen , Deeter Merritt , Jones Dylan B. A. , Arellano Avelino F. , Henze Daven K.
Published: October 2016

Abstract. Long-term measurements from satellites and surface stations have demonstrated a decreasing trend of tropospheric carbon monoxide (CO) in the Northern Hemisphere over the past decade. Likely explanations for this decrease include changes in anthropogenic, fires, and/or biogenic emissions or changes in the primary chemical sink hydroxyl radical (OH). Using remotely sensed CO measurements from the Measurement of Pollution in the Troposphere (MOPITT) satellite instrument, in-situ methyl chloroform (MCF) measurements from World Data Centre for Greenhouse Gases (WDCGG), and the adjoint of the GEOS-Chem model, we estimate the change in global CO emissions from 2001–2015. We show that the loss rate of MCF varies by 0.2 % in the past 15 years, indicating that changes in global OH distributions do not explain the recent decrease in CO. Our two-step inversion approach for estimating CO emissions is intended to mitigate the effect of bias errors in the MOPITT data as well as model errors in transport and chemistry, which are the primary uncertainties when quantifying CO emissions using these remotely sensed data. Our results confirm that the decreasing trend of tropospheric CO in the Northern Hemisphere is due to decreasing CO emissions from anthropogenic and biomass burning sources. In particular, we find decreasing CO emissions from the United States and China in the past 15 years, unchanged anthropogenic CO emissions from Europe since 2008, and likely a positive trend from India and southeast Asia, in contrast to recently reported results. We find decreasing trends of biomass burning CO emissions from boreal North America, boreal Asia and South America, but little change over Africa. The inconsistency between our analysis with recent study suggests more efforts are needed for robust conclusion about the variation of anthropogenic CO emissions for India and Southeast Asia.
Comparison of aerosol LIDAR retrieval methods for boundary layer height detection using ceilometer backscatter data
Authors: Caicedo Vanessa , Rappenglueck Bernhard , Lefer Barry , Morris Gary , Toledo Daniel , Delgado Ruben
Published: October 2016

Abstract. Three algorithms for estimating the boundary layer heights are assessed: an aerosol gradient method, a cluster analysis method, and a Haar wavelet method. Over 40 daytime radiosonde profiles are used to compare aerosol backscatter boundary layer heights retrieved by a Vaisala CL31 ceilometer. Overall good agreement between radiosonde and aerosol derived boundary layer heights was found for all methods. The cluster method was found to be particularly sensitive to noise in ceilometer signals and lofted aerosol layers (48.8 % of comparisons), while the gradient method showed limitations in low aerosol backscatter conditions. The Haar Wavelet method demonstrating to be the most robust only showing limitations (22.5 % of all observations) due to the basic assumptions used to derive BLH from aerosol backscatter concentrations rather than errors with the algorithm itself. Disagreement between thermodynamically and aerosol derived boundary layer heights and the methodology used to estimate these heights was seen with all methods.
Physiological response of a golden tide alga (Sargassum muticum) to the interaction of ocean acidification and phosphorus enrichment
Authors: Xu Zhiguang , Gao Guang , Xu Juntian , Wu Hongyan
Published: October 2016

Abstract. The evolvement of golden tides would be influenced by global change factors, such as ocean acidification and eutrophication, but the related studies are very scarce. In this study, we cultured a golden tide alga, Sargasssum muticum, at two levels of pCO2 (400, 1000 µatm) and phosphate (0.5 µM, 40 µM) conditions to investigate the interactive effects of elevated pCO2 and phosphate on physiological properties of the thalli. The higher pCO2 level and phosphate (P) level alone increased the relative growth rate by 40.82 % and 47.78 %, net photosynthetic rate by 46.34 % and 55.16 %, soluble carbohydrates by 32.78 % and 61.83 % respectively whilst the combination of these two levels did not promote growth or soluble carbohydrates further. The higher levels of pCO2 and P alone also enhanced the nitrate uptake rate by 68.27 % and 35.89 %, nitrate reductase activity by 89.08 % and 39.31 %, and soluble protein by 19.05 % and 15.13 % respectively. The nitrate uptake rate and soluble protein was further enhanced although the nitrate reductase activity was reduced when the higher levels of pCO2 and P worked together. The higher pCO2 level and higher P level alone did not affect the dark respiration rate of thalli but they together increased it by 32.30 % compared to the condition of the lower pCO2 and lower P. The mute effect of the higher level of pCO2 and higher P on growth, soluble carbohydrates, combined with the promoting effect of it on soluble protein and dark respiration, suggests more energy was drawn from carbon assimilation to nitrogen assimilation at the condition of higher pCO2 and higher P, probably to act against the higher pCO2 caused acid-base perturbation via synthesizing H+ transport-related protein. Our results indicate ocean acidification and eutrophication may not boost the gold tides events synergistically although each of them alone has a promoting effect.