Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Daan Nel is active.

Publication


Featured researches published by Daan Nel.


Journal of Neuropsychiatry and Clinical Neurosciences | 2008

The neuropsychiatry and neuropsychology of Lipoid Proteinosis

Helena B. Thornton; Daan Nel; Dorothy Thornton; Jack van Honk; Gus A. Baker; Dan J. Stein

Lipoid proteinosis is a rare hereditary disease which often results in bilateral calcifications in the medial temporal region. Thirty-four adults living with lipoid proteinosis (>10% of the world population) were extensively assessed with standardized neuropsychiatric and neuropsychological measures. Of these, 27 patients representing a homogenous group living in the Northern Cape were matched with 47 controls. Subjects with lipoid proteinosis had a high incidence of neuropsychiatric disorders and performed poorly on facial recognition of positive and negative emotions and on many neuropsychological measures. These findings are consistent with involvement of the medial temporal areas in cognitive and emotive processing.


Progress in Neuro-psychopharmacology & Biological Psychiatry | 2003

fluoxetine decreases stereotypic behavior in primates

Charmaine Hugo; Jürgen V. Seier; Chris Mdhluli; W. M. U. Daniels; Brian H Harvey; D F Du Toit; Sonia Wolfe-Coote; Daan Nel; Dan J. Stein

BACKGROUND Primates reared in captivity may display stereotypic behaviors. These behaviors are arguably reminiscent of human obsessive-compulsive or posttraumatic symptoms, which respond to selective serotonin reuptake inhibitors (SSRIs). Captive primates with marked stereotypic behaviors were entered into a randomized controlled study of the SSRI, fluoxetine. METHODS A sample of 10 vervet monkeys with behaviors such as marked saluting, somersaulting, weaving, or head tossing was selected. Subjects were randomized to receive fluoxetine 1 mg/kg for 6 weeks (n=5) or no treatment (n=5). A rater blind to the medication status of subjects noted the frequency of the stereotypic behaviors. RESULTS Repeated-measures analysis of variance (RM-ANOVA) demonstrated a significant GroupxTime difference with significantly fewer stereotypic symptoms in the fluoxetine group by endpoint. At this time, three of the five fluoxetine-treated subjects (but none of the no-treatment subjects) were responders on the Clinical Global Impressions (CGI) change item (CGI < or =2). CONCLUSIONS Stereotypic behaviors in captive vervets gradually and partially decrease in response to administration of an SSRI, paralleling research on human anxiety symptoms. Further research on animal stereotypies may be useful in providing appropriate veterinary care, and in exploring the underlying neurobiology of certain psychiatric disorders.


Burns | 2012

The aetiology of adult burns in the Western Cape, South Africa

David Maritz; Lee A. Wallis; A. Elbie Van der Merwe; Daan Nel

Rural to urban migration to major cities in South Africa continues to lead to the proliferation of informal settlements. There is little recent published data on the epidemiology of adult burns in the Western Cape, South Africa. A retrospective review of patients on the Burn Unit database was undertaken, looking at patients admitted to the Burn Unit between January 2003 and December 2008. This study discusses the characteristics and outcome of patients who were treated at the Tygerburg Burn unit. A total of 1908 patients were admitted to the burn unit during the 6 year period under review. Most fatal injuries occurred in the 20-40 year age group. Injuries due to shack fires and fuel stoves comprised 21% (399) of all admissions. Mortality due to these injuries comprised 28% (137) of total mortality. Gas stoves accounted for 24% with kerosene stoves accounting for 71% of injuries. The burn death rate in this study (25%) was found to have increased dramatically from the last audit done from 1986 to 1995 in which a burn death rate of 7.5% was observed. Reasons for this are explored. It is likely that those with HIV/AIDS have poorer outcomes. Shack fires and injuries due to fuel stoves are a common reason for admission to the burn unit and mostly involve young male individuals. Other research from the Southern African region does not mention shack fires as a separate entity making it difficult to obtain an accurate idea of the scale of the problem. Their injuries are severe with a high mortality. The use of kerosene stoves are a major contributing factor. Recommendations include enforceable legislation to promote safer stove design, research into safer bio fuels and materials for building shacks as well promoting fire safety among schoolchildren in the community. Further research is needed to determine the impact of HIV/AIDS on the outcome of acute burns within the Southern African region.


Depression and Anxiety | 2008

Exploratory and confirmatory factor analysis of the Multidimensional Anxiety Scale for Children among adolescents in the cape town metropole of South Africa

Dylan S. Fincham; Johannes Schickerling; Michael Temane; Daan Nel; Winnie De Roover; Soraya Seedat

There are no published data on the factor structure of the Multidimensional Anxiety Scale for Children (MASC) among adolescents in the Cape Town metropole of South Africa. The objectives of this study were (i) to establish the exploratory factor structure of the MASC using a principal components exploratory factor analysis (EFA); (ii) to confirm the derived factor structure using confirmatory factor analysis (CFA); and (iii) to examine gender, age, and race effects among adolescents in the Western Cape of South Africa. A convenience sample of 1,051 adolescents was selected from nine different schools in the Cape Town metropole of South Africa. An EFA yielded a four‐factor structure congruent to the factor structure established previously in other samples. Furthermore, the CFA showed that the four‐factor structure fit the data well. Black participants reported significantly higher levels of Harm Avoidance than other racial groups, and Black and Coloured (mixed race) participants reported significantly higher levels of Anxious Coping than White and Asian participants. Black and Coloured participants reported significantly higher levels of Separation/Panic than White participants, and Black participants reported higher levels than Asian and Coloured participants. Finally, there were no significant age effects, but females scored significantly higher overall and on all MASC subscales. The MASC seems to be a useful tool for assessing and distinguishing anxiety symptoms among adolescents in the Cape Town metropole of South Africa. Depression and Anxiety, 2008.


Southern Forests | 2014

Variation in strength, stiffness and related wood properties in young South African-grown Pinus patula

C Brand Wessels; Francois S Malan; Daan Nel; Tim Rypstra

The objective of this study was to examine the variation in and intercorrelation among wood properties determining the suitability of 16- to 20-year-old South African-grown Pinus patula trees for structural timber. A total of 1 112 sawn boards from 340 logs, 170 trees and 17 different compartments were examined. Sawlogs were taken from two height levels from each tree. The mean modulus of elasticity measured on edge (MOEedge) was far below, and the mean twist higher than the limits set for structural grade softwood timber in South Africa. All the desirable properties for structural timber improved with distance from the pith with the exception of the fifth percentile value for modulus of rupture (MOR), which was higher at the pith than for the boards processed adjacent to the pith. Boards processed from the lower part of the stem were superior in most of the important properties compared to the properties higher up in the stem. The correlation between the dynamic modulus of elasticity (MOEdyn) and MOR of boards processed from the logs taken higher up in the stem was much weaker than in the case of the boards processed from the log taken from the lower part in the stem, suggesting that indirect (non-destructive) prediction of MOR decreased in reliability with increase in height in trees. A relatively strong negative correlation was found between the mean growth ring widths of the pith boards and the mean MOEdyn values per compartment, suggesting that slower initial growth in a compartment resulted in increased mean stiffness of boards from that compartment.


International Journal of Gynecology & Obstetrics | 2017

Fetal foot length at delivery as a tool for determining gestation length in non‐macerated stillbirths

Elaine Geldenhuys; Jean Coldrey; Colleen A. Wright; Daan Nel; Drucilla J. Roberts; Theonia K. Boyd; Hein J. Odendaal

To assess whether fetal foot length at autopsy could reliably indicate gestation duration at stillbirth and the effects of maceration on this method.


Maderas-ciencia Y Tecnologia | 2010

Correlation between drying defects, their parameters and moisture gradient in kiln-dried, south african grown Eucalyptus Grandis poles

Paul Mugabi; Tim Rypstra; H. F. Vermaas; Daan Nel

Non-destructive testing for drying defects in Eucalyptus grandis utility poles would be highly advantageous. These defects can negatively affect creosote preservative treatment and in-service performance. The objective of this study was to assess correlations between drying defects such as surface checking, honeycombing, collapse, their parameters and moisture content (MC) gradient in poles, to possibly find a simple and quick but reliable method to assess internal and external drying defects. Defects and moisture content gradients were measured in 39 kiln-dried E. grandis poles. After measuring surface check length, width and depth using a measuring tape, a ruler and a depth gauge, destructive sampling at the theoretical ground line (TGL) was done to measure the MC gradient between the shell and core of poles. Digital image analysis of cross-sections of discs cut at TGL was used to measure honeycomb check width, length and area, as well as counting individual closed surface checks. Collapse was assessed using qualitative methods. Results showed that honeycombing and collapse were positively, and surface checking and MC gradient were negatively correlated. Surface check width, length and depth were also correlated. Honeycomb count, check width, length and area were strongly correlated. It was concluded that measuring any of these surface check and/or honeycomb parameters may give meaningful deductions about the extent of surface checking and honeycombing respectively.


Israel Journal of Psychiatry and Related Sciences | 2008

Cluster Analysis of Obsessive-Compulsive Symptomatology: Identifying Obsessive-Compulsive Disorder Subtypes

Christine Lochner; Sian Hemmings; Craig J. Kinnear; Daan Nel; Soraya Seedat; Johanna C. Moolman-Smook; Dan J. Stein


Journal of Studies on Alcohol and Drugs | 2009

Alcohol-induced Psychotic Disorder: A comparative study on the clinical characteristics of patients with Alcohol Dependence and Schizophrenia

Gerhard P. Jordaan; Daan Nel; Richard H. Hewlett; Robin Emsley


Metabolic Brain Disease | 2014

Alcohol-induced psychotic disorder: brain perfusion and psychopathology-before and after anti-psychotic treatment

Gerhard P. Jordaan; James Warwick; Daan Nel; Richard H. Hewlett; Robin Emsley

Collaboration


Dive into the Daan Nel's collaboration.

Top Co-Authors

Avatar

Tim Rypstra

Stellenbosch University

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Paul Mugabi

Stellenbosch University

View shared research outputs
Top Co-Authors

Avatar

Dan J. Stein

University of Cape Town

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Robin Emsley

Stellenbosch University

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Brian H Harvey

Potchefstroom University for Christian Higher Education

View shared research outputs
Researchain Logo
Decentralizing Knowledge