The invisible support networks of doctoral candidates : what acknowledgement sections of doctoral theses reveal

CITATION: Leshem, S. & Bitzer, E. 2021. The invisible support networks of doctoral candidates : what acknowledgement sections of doctoral theses reveal. South African Journal of Higher Education, 35(3):1-12, doi:10.20853/35-3-3538.The original publication is available at http://www.journals.ac.za/index.php/sajheAlthough some argue that acknowledgement sections should not form part of doctoral theses, others welcome such sections and are of the opinion that they reflect original and personal contributions, constituting a neglected genre. Previous research on acknowledgement texts have focused more on their linguistic characteristics as related to the academic writing of theses. The present study, however, inquired into acknowledgement sections from a social support perspective. The aim of the study was to bring to light the dimension of the social milieu and its importance in supporting doctoral students in successfully achieving their doctorate. More specifically, the study sought to investigate the role of “significant others” in the academic success of doctoral students as reflected in the genres of acknowledgement in doctoral theses by analysing such texts from 30 completed doctoral theses in South Africa and Israel. Follow-up interviews with graduates assisted to probe deeper into the meaning of the texts. Although limited in nature, the study found that, based on who doctoral graduates acknowledge, several role-players and supporters seem to contribute to doctoral success. This includes family members, friends, colleagues, study supervisors, funders and university administrators. What also became clear was that doctoral candidates rely mainly on psycho-social forms of support and that particular kinds of such support are crucial at different stages of the doctoral journey. Acknowledgement studies confirm the doctoral research process as an activity stream that integrates the personal, the interpersonal and the institutional to reveal the mostly hidden, but very important, influences on the doctorate.https://www.journals.ac.za/index.php/sajhe/article/view/3538Publisher's versio

Multichannel interference mitigation methods in radio astronomy

Radio-astronomical observations are increasingly corrupted by RF interference, and online detection and filtering algorithms are becoming essential. To facilitate the introduction of such techniques into radio astronomy, we formulate the astronomical problem in an array signal processing language, and give an introduction to some elementary algorithms from that field. We consider two topics in detail: interference detection by rank estimation of short-term covariance matrices, and spatial filtering by subspace estimation and projection. We discuss experimental data collected at the Westerbork radio telescope, and illustrate the effectiveness of the space-time detection and blanking process on the recovery of a 3C48 absorption line in the presence of GSM mobile telephony interference.Comment: 39 pages, 18 figures.Enhanced figures can be downloaded from http://cas.et.tudelft.nl/~leshem/postscripts/leshem/figs34567.ps.gz To appear in Astrophysical Journal Supplements serie

Cutaneous manifestations of COVID-19: Report of three cases and a review of literature

Background: Various cutaneous manifestations have been observed in patients with COVID-19 infection. However, overall similarities in the clinical presentation of these dermatological manifestations have not yet been summarized. Objective: This review aims to provide an overview of various cutaneous manifestations in patients with COVID-19 through three case reports and a literature review. Methods: A literature search was conducted using PubMed, OVID, and Google search engines for original and review articles. Studies written in the English language that mentioned cutaneous symptoms and COVID-19 were included. Results: Eighteen articles and three additional cases reported in this paper were included in this review. Of these studies, 6 are case series and 12 are case report studies. The most common cutaneous manifestation of COVID-19 was found to be maculopapular exanthem (morbilliform), presenting in 36.1% (26/72) patients. The other cutaneous manifestations included: a papulovesicular rash (34.7%, 25/72), urticaria (9.7%, 7/72), painful acral red purple papules (15.3%, 11/72) of patients, livedo reticularis lesions (2.8%, 2/72) and petechiae (1.4%, 1/72). Majority of lesions were localized on the trunk (66.7%, 50/72), however, 19.4% (14/72) of patients experienced cutaneous manifestations in the hands and feet. Skin lesion development occurred before the onset of respiratory symptoms or COVID-19 diagnosis in 12.5% (9/72) of the patients, and lesions spontaneously healed in all patients within 10 days. Majority of the studies reported no correlation between COVID-19 severity and skin lesions. Conclusion: Infection with COVID-19 may result in dermatological manifestations with various clinical presentations, which may aid in the timely diagnosis of this infection

The association between mental health trajectories and somatic symptoms following a second lockdown in Israel : a longitudinal study

Objectives To identify mental health prospective trajectories before and after a second lockdown during the COVID-19 pandemic and their associations with somatic symptoms. Design Prospective Study. Setting Population-based study drawn from a probability-based internet panel of over 100 000 Israelis. Participants Adults aged 18 years or more, representative of the adult Israeli population. The participants were measured at two time points (time 1 (T1) pre-second lockdown N=1029; response rate=76.17%; time 2 (T2) post-second lockdown N=764; response rate=74.24%). Main outcome measures Trajectories of anxiety and adjustment disorder based on clinical cut-off score for probable diagnoses across T1-T2, somatic symptoms at T2. The four trajectories: stable-low, (no probable diagnosis), stable-high (stable probable diagnosis), exacerbation (no probable diagnosis at T1, probable diagnosis at T2), recovery (probable diagnosis at T1, no probable diagnosis at T2). Results Three anxiety trajectories predicted probable somatic symptoms (stable-high OR=6.451; exacerbation OR=5.379; recovery OR=2.025) compared with the stable-low trajectory. The three adjustment disorder trajectories also predicted somatic symptoms (stable-high OR=4.726; exacerbation OR=6.419; recovery OR=4.666) compared with the stable-low trajectory. Conclusions Our data show elevated somatic symptoms among those whose mental health trajectories were poor, exacerbated and those who recovered following the second lockdown. The presentation of somatic symptoms may mask psychological vulnerabilities, even among those who appear to have recovered from the stressor. This indicates that lockdown may be a double-edged sword and should be carefully administered given these populations vulnerabilities

The Ukraine-Russia war : a symptoms network of complex posttraumatic stress disorder during continuous traumatic stress

Objective: This study is aimed to test the symptoms network of ICD-11 Complex Post-traumatic Stress Disorder (CPTSD) symptoms, using data collected from Ukrainian civilians during the 2022 Russia-Ukraine war. Findings can inform our understanding of the stress response in individuals exposed to continuous trauma and give insight into the nature of CPTSD during war. Methods: A network analysis was conducted on CPTSD symptoms as assessed by the International Trauma Questionnaire using data from a nationally representative sample of 2000 Ukrainians. Results: While Post-traumatic Stress Disorder (PTSD) and Disturbances in Self Organization (DSO) clusters did not enmesh, several communities within these clusters were merged. Results highlight that in terms of strength centrality, emotional dysregulation (emotional numbing) and a heightened sense of threat were most prominent. Conclusion: The results confirm the ICD-11 structure of CPTSD but suggest that continuous traumatic stress manifests in more condensed associations between CPTSD symptoms and that emotional regulation may play a vital role in activating the CPTSD network. War-exposed populations could be provided with scalable, brief self-help materials focused on fostering emotion regulation and sense of threat

Optimization of placebo use in clinical trials with systemic treatments for atopic dermatitis: an International Eczema Council survey-based position statement.

Background: As novel systemic therapeutics for patients with atopic dermatitis (AD) are developed, ethical and methodological concerns regarding placebo-controlled-trials (PCT) have surfaced. Objective: To guide the design and implementation of PCT in AD, focusing on trials with systemic medications. Methods: A subgroup of the International Eczema Council (IEC) developed a consensus e-survey, which was disseminated to IEC members. Results: The response rate was 43/82 (52%). Consensus was reached on 24/27 statements and on 3/11 options from multiple-selection statements, including: performing monotherapy studies in proof-of-concept phases; avoiding concomitant topical corticosteroids or calcineurin inhibitors until a predefined timepoint as rescue (borderline consensus); selection of sites and assessors with recognized expertise in AD clinical trials; clear definition and identification of baseline disease severity; minimizing time and proportion of patients on placebo; using daily emollients with several options provided; instigating open-label extension studies for enrolment after a predefined timepoint; and including outcomes which set a higher bar for disease clearance. Conclusion: Conducting PCT in AD requires balancing several, sometimes opposing principles, including ethics, methodology, regulatory requirements and real-world needs. This paper can provide a framework for conducting PCT with systemic medications for patients with AD

Radio Interferometric Calibration Using The SAGE Algorithm

The aim of the new generation of radio synthesis arrays such as LOFAR and SKA is to achieve much higher sensitivity, resolution and frequency coverage than what is available now, especially at low frequencies. To accomplish this goal, the accuracy of the calibration techniques used is of considerable importance. Moreover, since these telescopes produce huge amounts of data, speed of convergence of calibration is a major bottleneck. The errors in calibration are due to system noise (sky and instrumental) as well as the estimation errors introduced by the calibration technique itself, which we call solver noise. We define solver noise as the distance between the optimal solution (the true value of the unknowns, uncorrupted by the system noise) and the solution obtained by calibration. We present the Space Alternating Generalized Expectation Maximization (SAGE) calibration technique, which is a modification of the Expectation Maximization algorithm, and compare its performance with the traditional Least Squares calibration based on the level of solver noise introduced by each technique. For this purpose, we develop statistical methods that use the calibrated solutions to estimate the level of solver noise. The SAGE calibration algorithm yields very promising results both in terms of accuracy and speed of convergence. The comparison approaches we adopt introduce a new framework for assessing the performance of different calibration schemes.Comment: 12 pages, 10 figures, Accepted for publication in MNRA

Evaluation of the health-related quality of life of children in Schistosoma haematobium-endemic communities in Kenya: a cross-sectional study.

BACKGROUND: Schistosomiasis remains a global public health challenge, with 93% of the ~237 million infections occurring in sub-Saharan Africa. Though rarely fatal, its recurring nature makes it a lifetime disorder with significant chronic health burdens. Much of its negative health impact is due to non-specific conditions such as anemia, undernutrition, pain, exercise intolerance, poor school performance, and decreased work capacity. This makes it difficult to estimate the disease burden specific to schistosomiasis using the standard DALY metric. METHODOLOGY/PRINCIPAL FINDINGS: In our study, we used Pediatric Quality of Life Inventory (PedsQL), a modular instrument available for ages 2-18 years, to assess health-related quality of life (HrQoL) among children living in a Schistosoma haematobium-endemic area in coastal Kenya. The PedsQL questionnaires were administered by interview to children aged 5-18 years (and their parents) in five villages spread across three districts. HrQoL (total score) was significantly lower in villages with high prevalence of S. haematobium (-4.0%, p<0.001) and among the lower socioeconomic quartiles (-2.0%, p<0.05). A greater effect was seen in the psychosocial scales as compared to the physical function scale. In moderate prevalence villages, detection of any parasite eggs in the urine was associated with a significant 2.1% (p<0.05) reduction in total score. The PedsQL reliabilities were generally high (Cronbach alphas ≥0.70), floor effects were acceptable, and identification of children from low socioeconomic standing was valid. CONCLUSIONS/SIGNIFICANCE: We conclude that exposure to urogenital schistosomiasis is associated with a 2-4% reduction in HrQoL. Further research is warranted to determine the reproducibility and responsiveness properties of QoL testing in relation to schistosomiasis. We anticipate that a case definition based on more sensitive parasitological diagnosis among younger children will better define the immediate and long-term HrQoL impact of Schistosoma infection

Biomolecular condensates formed by designer minimalistic peptides

Inspired by the role of intracellular liquid-liquid phase separation (LLPS) in formation of membraneless organelles, there is great interest in developing dynamic compartments formed by LLPS of intrinsically disordered proteins (IDPs) or short peptides. However, the molecular mechanisms underlying the formation of biomolecular condensates have not been fully elucidated, rendering on-demand design of synthetic condensates with tailored physico-chemical functionalities a significant challenge. To address this need, here we design a library of LLPS-promoting peptide building blocks composed of various assembly domains. We show that the LLPS propensity, dynamics, and encapsulation efficiency of compartments can be tuned by changes to the peptide composition. Specifically, with the aid of Raman and NMR spectroscopy, we show that interactions between arginine and aromatic amino acids underlie droplet formation, and that both intra- and intermolecular interactions dictate droplet dynamics. The resulting sequence-structure-function correlation could support the future development of compartments for a variety of applications

A different role for hydrogen peroxide and the antioxidative system under short and long salt stress in Brassica oleracea roots

Salinity affects normal growth and development of plants depending on their capacity to overcome the induced stress. The present study was focused on the response and regulation of the antioxidant defence system in Brassica oleracea roots under short and long salt treatments. The function and the implications of hydrogen peroxide as a stressor or as a signalling molecule were also studied. Two different zones were analysed—the elongation and differentiation zone and the fully differentiated root zone—in order to broaden the knowledge of the different effects of salt stress in root. In general, an accumulation of hydrogen peroxide was observed in both zones at the highest (80 mM NaCl) concentration. A higher accumulation of hydrogen peroxide was observed in the stele of salt-treated roots. At the subcellular level, mitochondria accumulated hydrogen peroxide in salt-treated roots. The results confirm a drastic decrease in the antioxidant enzymes catalase, ascorbate peroxidase, and peroxidases under short salt treatments. However, catalase and peroxidase activities were recovered under long salt stress treatments. The two antioxidant molecules analysed, ascorbate and glutathione, showed a different trend during salt treatments. Ascorbate was progressively accumulated and its redox state maintained, but glutathione was highly accumulated at 24 h of salt treatment, but then its concentration and redox state progressively decreased. Concomitantly, the antioxidant enzymes involved in ascorbate and glutathione regeneration were modified under salt stress treatments. In conclusion, the increase in ascorbate levels and the maintenance of the redox state seem to be critical for root growth and development under salt stress