Developmental and sex modulated neurological alterations in autism spectrum disorder

Autism Spectrum Disorder (ASD) was first described in 1943 by Dr. Leo Kranner in a case study published in The Nervous Child. It is a neurodevelopment disorder, with a range of clinical symptoms. According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), used by clinicians to diagnose mental disorders, a child needs to have persistent social deficits, language impairments, and repetitive behaviors, that cannot be explained by neurological damage or intellectual disability. It is known that children diagnosed with ASD are often are developmentally delayed therefore alterations in the typical developmental trajectory should be a major factor in consideration when studying ASD. As of 2016, 1 in 68 children in the USA is diagnosed with ASD, of those diagnosed young males are four times more likely to be diagnosed than their female peers. Although genetic and behavioral theories exist to explain these differences, the cause for the disparity is still unknown. This Dissertation presents a unique opportunity to understand the intersection of altered neurodevelopment and the alarming sex disparities in patients with ASD from a neuroimaging perspective. The hypothesis is that there exist differences due to development and sex in with ASD. Access to ABIDE (Autism Brain Imaging Data Exchange), a open source large scale data sharing consortium of functional and anatomical MR data. Analyzing MR data for alterations due to ASD, developmental trajectory, and sex as well as the intersection of these factors. Theses modulations are observed in three Project Aims that employ various analytical approaches: (1) Structural Morphology, (2) Resting-state Functional Connectivity, and (3) Graph Theory. The major findings lie at the interaction of these three factors; developmental stage-by-diagnosis-by-sex. Structural Morphological Analyses of anatomical data show differences in cortical thickness, on the left rostral middle frontal gyrus and surface area in along the sensory motor strip, of the left paracentral gyrus and right precentral gyrus. Resting-state Functional Connectivity analyzed in multiple data driven approaches, and altered resting state connectivity patterns between the left frontal parietal network and the left parahippcampal gyrus are reported. The regions found in the Morphological Analyses are used as seeds for a priori connectivity analysis, connectivity between the left rostral middle frontal cortex and bilateral superior temporal gyrus as well as the right precentral gyrus and right middle frontal gyrus and left inferior frontal gyrus are described. Finally using Graph Theory analysis, which quantifies a whole brain connectivity matrix to calculate metrics such as path length, cluster coefficient, local efficiency, and betweeness centrality all of which are altered by the interaction of all three factors. The last investigation is an attempt to correlate the behavioral assessments, conducted by clinicians with theses neuroimaging findings to determine if there exist a relationship between them. Significant interaction effects of sex and development on ASD diagnosis are observed. The goal of the Study is to provide more information on the disorder that is by nature highly heterogeneous in symptomatology. Studying these interactions, may be key to better understand a disorder that was introduced into the medical literature 75 years ago

Understanding the Aggregation of Model Island and Archipelago Asphaltene Molecules near Kaolinite Surfaces using Molecular Dynamics

The solubility of asphaltenes in hydrocarbons changes with pressure, composition, and temperature, leading to precipitation and deposition, thereby causing one of the crucial problems that negatively affects oil production, transportation, and processing. Because, in some circumstances, it might be advantageous to promote asphaltene agglomeration into small colloidal particles, molecular dynamics simulations were conducted here to understand the impacts of a chemical additive inspired by cyclohexane on the mechanism of aggregation of model island and archipelago asphaltene molecules in toluene. We compared the results in the presence and absence of a kaolinite surface at 300 and 400 K. Cluster size analyses, radial distribution functions, angles between asphaltenes, radius of gyration, and entropic and energetic calculations were used to provide insights on the behavior of these systems. The results show that the hypothetical additive inspired by cyclohexane promoted the aggregation of both asphaltenes. Structural differences were observed among the aggregates obtained in our simulations. These differences are attributed to the number of aromatic cores and side chains on the asphaltene molecules as well as to that of heteroatoms. For the island structure, aggregation in the bulk phase was less pronounced than that in the proximity of the kaolinite surface, whereas the opposite was observed for the archipelago structure. In both cases, the additive promoted stacking of asphaltenes, yielding more compact aggregates. The results provided insights into the complex nature of asphaltene aggregation, although computational approaches that can access longer time and larger size scales should be chosen for quantifying emergent meso- and macroscale properties of systems containing asphaltenes in larger numbers than those that can currently be sampled via atomistic simulations

‘You’re Othered here and you’re Othered there’: Centring the clothing practices of Black Muslim Women in Britain

By using clothing practices, the thesis illustrates how we become Black Muslim women in relation to a multitude of objects, bodies, gazes and spaces. This contributes to research within critical race studies on the performance and production of racialised bodies across different spaces. Specifically, the thesis asks what analytical tools can be developed to understand how Black Muslim women negotiate presentations beyond a fixed categorisation of our beings and how clothing practices highlight different experiences of being Black Muslim women across a multitude of spaces. This extends work on the territorialisation of the body, emotional and affective geographies, performativity and material culture, as well as visual studies through phenomenological readings of race. Building these fields through the lens of Black Muslim stylisation illustrates how centring Black Muslim women in Britain provides the opportunity to develop new and critical knowledges on the co-production of different bodies, gazes and spaces within Social Geography. I explore how we perform our beings through the use of clothes journals and semi-structured interviews (based on Black feminist dialogue) with 21 Black Muslim women in Manchester and Sheffield. These methods (along with the research design and analysis) speak from and build upon a wider ethical commitment to reflexively build knowledge with Black Muslim women, and to challenge spaces of knowledge production and legitimisation that have excluded and/or objectified this diversity of beings across different spaces. To highlight these experiences of being, there are three analytical tools that come in and out of focus throughout the project; comfort, layering and visibility are developed within the interludes running between the empirical chapters. Meanwhile, the empirical chapters expand on our beings as shifting in relation to our presentations across three spaces (home, prayer and work). Home clothing illustrates how boundaries around the body shifts as we interact with different bodies (and boundaries) in and around the home. The clothes used for prayer speaks to the relationship between layering and prayer’s brief (and racialised) temporality: even after the material layer used for prayer is removed, the performance of prayer remains part of our overarching beings. Finally, I use work outfits to think through the clothing practices used to ‘fit’ into (i.e. negotiate visibility within) different spaces. By framing this thesis through the geographies of Black Muslim women, I extend research on how bodies are produced and shift across different spaces. This highlights different experiences of being across a multitude of spaces, and challenges a homogeneous and static reading of Black (and) Muslim women as Other to a white Self

Evaluation of Burnout, Coping Strategies and Resilience in Paediatric Oncology Health Care Workers in Cape Town

Background: Burnout is a work-related condition with a significant footprint in the medical profession. It is characterised by emotional exhaustion (EE), depersonalisation (DP), and a low sense of personal accomplishment (PA) at one’s job. Depending on situational and individual factors, the prevalence of burnout among healthcare workers (HCWs) has shown an upward trajectory with peaks in certain medical specialities. Paediatric oncology unit (POU) HCWs are at a high risk of developing burnout because of the immense physical and emotional involvement that can be associated with caring for children with cancer. The burnout process can, however, be influenced by adopted coping strategies and resilience. Research into the phenomenon of burnout and associated factors in POU HCWs is low in South Africa in spite of the global attention it has commanded. Because of the need to institute appropriate and acceptable intervention strategies and to avoid erroneous conclusions often associated with burnout, it is imperative to understand the local prevalence and the possible associated factors. This study, therefore, seeks to establish the prevalence of burnout in POU HCWs and to understand how the adopted coping strategies and level of resilience influence the burnout process in a defined setting. Acknowledging and understanding how these psychosocial factors affect HCWs is fundamental to designing interventions to reduce work-related stress conditions. Objectives: This study seeks to determine the following: prevalence of burnout among POU HCWs in Red Cross War Memorial Children’s Hospital, Cape Town; identify adopted coping strategies by the HCWs; evaluate the level of resilience in the HCWs; and make recommendations that may help reduce burnout in paediatric oncology care and, probably, other fields of health care in South Africa. Methodology: This research used a mixed method approach (quantitative and qualitative) to explore burnout, coping and resilience amongst POU HCWs. A questionnaire consisting of validated instruments (Maslach Burnout Inventory-Human Services Survey [MBI- HSS], Brief Resilience Scale [BRS], the Brief COPE and researcher-designed questions) was used to conduct a survey after obtaining ethical clearance (HREC REF: 051/2017). Depending on preference, electronic or paper-based questionnaires were distributed to POU staff. Data analysis was performed using Microsoft EXCEL (2010 version). Results: The response rate was 50% (n= 25). Five out of the total respondents were dropped due to gross omissions in responses to the survey questions. The majority of the respondents were females (95%), and by profession, nurses had the highest representation (80%). Eightyfive per cent (85%) of the respondents have worked in the POU for more than a year. The burnout prevalence was 15% – 45% across the three dimensions of burnout - high EE (20%), high DP (15%) and reduced PA (45%). The majority (70%) of the respondents were moderately resilient. The coping styles predominantly used by the respondents in this study were positive reframing, religion, acceptance, planning, self-distraction and active coping. The least used coping styles were substance use, denial and behavioural disengagement, which are all maladaptive coping strategies. There was no statistically significant association between burnout and demographic characteristics. However, with a high prevalence of 45%, reduced personal accomplishment (rPA) was also associated with most demographic characteristics. rPA was high in females; age groups 25-25 and 46-60; single and married; respondents with number of children >1; respondents with a graduate level of education; POU professionals that are nurses and administrators; respondents with work experience in medicine and work experience in oncology for less than 10 years. Respondents with low levels of resilience experienced average levels of burnout as evidenced by average EE and DP scores, while those with moderate levels of resilience experienced low burnout as evidenced by low EE and DP scores (P< 0.05) Furthermore, EE and DP correlated negatively with the BRS while PA correlated positively with the BRS. Concerning coping strategies, EE and DP correlated positively with denial, substance use, behavioural disengagement, venting and self-blame. PA correlated positively with emotional support, positive reframing and religion but negatively correlated with active coping. Generally, the respondents expressed the desire for better goal-focused teamwork in the POU as well as the implementation of effective intervention strategies. Conclusion: The prevalence of burnout in this study is between 15% - 45%. The particularly high prevalence of reduced personal accomplishment (45%) is of interest because it cuts across most demographic features. This is suggestive of a stronger influence of situation specific factors, common to all respondents, contributing to burnout. The predominant use of emotion and problem-focused coping methods, and the moderate level of resilience in the majority of the staff appear to be protective against burnout. There is, however, the need and desire for implementation of effective group and institutional intervention programmes for burnout in the POU staff in terms of availability, awareness and accessibility

Assessing the Impact of Usability from Evaluating Mobile Health Applications

Software applications that are used to monitor, track, and improve health are called Mobile Health Applications or mHAs. They are developed with or without the help of medical professionals to potentially aid health, achieve health goals and improve lifestyle or behavior. Although mobile Health Applications have been on the market since the advent of mobile applications, the pandemic saw to a 25% increase in the number of mobile health applications available on the app stores. This indicates the growing demand for mHAs. This research was conducted to evaluate the impact of usability of mobile health applications. The dataset used to carry out this research is a review data set of health-condition management focused apps. These apps managed conditions like Diabetes, Depression, Hypertension, etc. System Usability Score, Net Promoter Score, App Ratings, Patient engagement was some of the features that were used to conduct the research. There were low correlations between App’s reaction to dangerous information and usability score (0.17), Existence of privacy policy and usability score (-0.032), IOS App Rating and Usability Score (0.053), Android App Rating and Usability Score (-0.029). Patient, Caregiver/Clinicians engagement-based variables like ‘does the app makes reference to specific disease guidelines’, ‘in what way does the app engage patients’, ‘does the app provide support through social media’ showed higher correlations with usability scores and clinical utility. It is recommended that to evaluate the usability of mobile health applications, a combination of usability measuring methods be used

Delayed referral and treatment of paediatric cancer in Nigeria: Time to stop blaming the victim

Background: Caregiver delay in presentation has been cited as a major contributor to poor prognosis of paediatric cancers in low-middle income countries like Nigeria. This study explored the time duration between onset of symptoms and presentation to healthcare facilities, diagnosis, and referral for specialist care. Methods: Data were compiled from caregivers of newly registered children at a teaching hospital in Nigeria. Sociodemographic and clinical history of the child were taken. Type of cancer, date of diagnosis, centre where the diagnosis was made, treatment start date, and duration of symptoms until treatment were elicited from consenting caregivers and documented. Results: Acute lymphoblastic leukaemia was the most prevalent cancer type among the patients. The mean time from first symptom to presentation was 15 weeks and from presentation at any health care facility to specialist referral and diagnosis was 38 and 39 weeks, respectively. Time from diagnosis to treatment was a mean of 8 weeks (range: 1 to 27 weeks) Conclusion: Delayed presentation has become a commonly cited factor for poor cancer outcomes in Nigeria and may often inaccurately assign blame to the patient/caregivers. The results of this study point to delayed detection, delayed diagnosis and delayed referral for specialist care, as more accurate contributors to late-stage presentation and consequently worse outcomes of paediatric cancers in Nigeria. Strengthening of community and primary level healthcare professionals’ understanding of paediatric cancers, establishment of simple detection algorithms and national implementation of efficient referral protocols will potentially reduce delays in specialist attention and improve outcomes

Structural reliability of pre-stressed concrete containments

This paper presents probabilistic analysis of structural capacity of pre-stressed concrete containments subjected to internal pressure. The conventional design methods for containments are based on allowable stress codes which ensure certain factor of safety between expected load and expected structural strength. Such an approach may give different values of structural reliability in different situations. In recent years, two international round robin exercises have been conducted aimed at predicting the capacity of lined and unlined pre-stressed concrete containments used in nuclear industry. These exercises involved experimental testing and numerical analysis of the models. The first exercise involved 1/4 scale steel-lined Pre-stressed Concrete Containment Vessel (PCCV) which was tested at Sandia National Laboratories (SNL) in USA. The second used an unlined containment being tested by the Bhabha Atomic Research Centre (BARC), Tarapur, India. These studies are essentially deterministic studies that have helped validate the analysis methodology and modelling techniques that can be used to predict pre-stressed concrete containment capacity and failure modes. The paper uses these two examples to apply structural reliability method to estimate the probability of failure of the containment. The two international round robin exercises have already established the ultimate structural collapse mode of the containments under internal pressure loading which indicate that the failure takes place in the general field of the containment wall around mid-height and away from any major structural discontinuities like the penetrations. This is because robust design procedures have been used to avoid structural failure at discontinuities by providing adequate compensation. Based on these experimental studies and the attendant numerical analyses a failure function is presented that assumes first yielding in the hoop direction at mid-height of the cylinder wall. A failure function equating the free-field membrane hoop stress to the hoop strength as a function of cross-sectional area (per unit height) and yield stresses of concrete, rebar, liner plate and tendons is developed. First Order Reliability Method (FORM) is applied to predict probability of failure of the containments. Probability of failure vs internal pressure is presented for both types of containments. The paper presents a simple method to establish structural reliability of a pre-stressed concrete containment which can be useful for probabilistic safety assessment when considering extreme events that lead to over-pressurisation of the containment. The FORM approach was validated by comparison to the results of analogous calculations using Subset Simulation and Importance Sampling techniques for Monte Carlo simulation. It was found that at high pressures the Advanced FORM approach yields a good approximation to the true probability of failure. The sensitivity of the probability of failure to the assumed coefficients of variation of properties of the containment was studied using the Sobol and Total Sensitivity Indices. At design pressure it was found that the coefficients of variation of the tendon yield and tendon area are the most important parameters followed by the applied pressure and containment radius. At higher pressures it was found that the coefficients of variation of the applied pressure and containment radius are the most important parameters. The variability of the probability of failure is decreased at higher pressures, but the coefficients of variation still play an important role

Physicochemical and sensory properties of corn starch custard soured with tamarind, soursop and lime

Custard is a convenient food product, similar to ogi in appearance and viscosity, but lacks the sour taste typical of ogi. In this study, extracts (10% w/w) from tamarind, soursop and lime was added to custard samples and the physicochemical and sensory properties of the mixture was analysed. Corn gruel was included as the reference sample. Carbohydrate was the major component of the corn gruel (61.72%) and custard samples (66.27-74.42%). Corn gruel had substantially higher protein content (18.03%) than custard samples (8.03-8.62%). Custard samples were more dispersible in water, showed higher swelling power and significantly higher peak and final viscosities than the corn flour sample. However, the addition of souring agent did not significantly alter the cooking time and pasting temperature of custard. Custard may be soured with lime, tamarind and soursop to improve dispersibility, consistency, appearance, viscosity and sourness without significant changes in the overall acceptability of the product

Occurrence of Orthetrum abbotti Calvert (1892) (Odonata, Libellulidae) and intraguild predation on Clarias gareipinus Burchell, 1822 (Suliformes, Clariidae) and Oreochromis niloticus L., 1758 (Perciformes, Cichlidae) fry in Lagos fish farms

Intraguild predation occurs when species competing for the same resource prey upon or parasitize one another. This may result in economic losses under commercial circumstances. A survey of the insect species of fish farms in Badagry and Ojo Areas of Lagos State, Nigeria was carried out followed by an evaluation of the predatory ability of Orthetrum abbotti nymphs on fish fry. Nymph predation was evaluated in the laboratory against fry of Clarias gariepinus and Oreochromis niloticus. Samples of insects were randomly collected from 10 earthen ponds, 10 concrete ponds and the vegetation surrounding the ponds and identified over a period of 12 weeks from three study fish farms. Six species of insects belonging to four orders namely Notonecta unifasciata, Gerris remigis, O. abbotti, Aedes aegypti, Dysticus marginalis and Acentria ephemerella syn. niveus were collected from the ponds. Studies on feeding preference of 5th nymphal instar of O. abbotti on fry of C. gariepinus and O.  niloticus over other food types revealed  that the dragonfly preferred to feed more on C. gariepinus fry than on O. niloticus although there was no significant difference in the number of O. niloticus and C. gariepinus fry preyed upon by O. abbotti nymphs