Metadiscourse Tagging in Academic Lectures

This thesis presents a study into the nature and structure of academic lectures, with a special focus on metadiscourse phenomena. Metadiscourse refers to a set of linguistics expressions that signal specific discourse functions such as the Introduction: “Today we will talk about...” and Emphasising: “This is an important point”. These functions are important because they are part of lecturers’ strategies in understanding of what happens in a lecture. The knowledge of their presence and identity could serve as initial steps toward downstream applications that will require functional analysis of lecture content such as a browser for lectures archives, summarisation, or an automatic minute-taker for lectures. One challenging aspect for metadiscourse detection and classification is that the set of expressions are semi-fixed, meaning that different phrases can indicate the same function. To that end a four-stage approach is developed to study metadiscourse in academic lectures. Firstly, a corpus of metadiscourse for academic lectures from Physics and Economics courses is built by adapting an existing scheme that describes functional-oriented metadiscourse categories. Second, because producing reference transcripts is a time-consuming task and prone to some errors due to the manual efforts required, an automatic speech recognition (ASR) system is built specifically to produce transcripts of lectures. Since the reference transcripts lack time-stamp information, an alignment system is applied to the reference to be able to evaluate the ASR system. Then, a model is developed using Support Vector Machines (SVMs) to classify metadiscourse tags using both textual and acoustical features. The results show that n-grams are the most inductive features for the task; however, due to data sparsity the model does not generalise for unseen n-grams. This limits its ability to solve the variation issue in metadiscourse expressions. Continuous Bag-of-Words (CBOW) provide a promising solution as this can capture both the syntactic and semantic similarities between words and thus is able to solve the generalisation issue. However, CBOW ignores the word order completely, something which is very important to be retained when classifying metadiscourse tags. The final stage aims to address the issue of sequence modelling by developing a joint CBOW and Convolutional Neural Network (CNN) model. CNNs can work with continuous features such as word embedding in an elegant and robust fashion by producing a fixed-size feature vector that is able to identify indicative local information for the tagging task. The results show that metadiscourse tagging using CNNs outperforms the SVMs model significantly even on ASR outputs, owing to its ability to predict a sequence of words that is more representative for the task regardless of its position in the sentence. In addition, the inclusion of other features such as part-of-speech (POS) tags and prosodic cues improved the results further. These findings are consistent in both disciplines. The final contribution in this thesis is to investigate the suitability of using metadiscourse tags as discourse features in the lecture structure segmentation model, despite the fact that the task is approached as a classification model and most of the state-of-art models are unsupervised. In general, the obtained results show remarkable improvements over the state-of-the-art models in both disciplines

Seroprevalence of SARS-CoV-2 (COVID-19) among Healthcare Workers in Saudi Arabia: Comparing Case and Control Hospitals

Healthcare workers (HCWs) stand at the frontline for fighting coronavirus disease 2019 (COVID-19) pandemic. This puts them at higher risk of acquiring the infection than other individuals in the community. Defining immunity status among health care workers is therefore of interest since it helps to mitigate the exposure risk. This study was conducted between May 20th and 30th, 2020. Eighty-five hospitals across Kingdom of Saudi Arabia were divided into 2 groups: COVID-19 referral hospitals are those to which RT-PCR-confirmed COVID-19 patients were admitted or referred for management (Case-hospitals). COVID-19 nonaffected hospitals where no COVID-19 patients had been admitted or managed and no HCW outbreak (Control hospitals). Next, seroprevalence of severe acute respiratory syndrome coronavirus 2 among HCWs was evaluated; there were 12,621 HCWs from the 85 hospitals. There were 61 case-hospitals with 9379 (74.3%) observations, and 24 control-hospitals with 3242 (25.7%) observations. The overall positivity rate by the immunoassay was 299 (2.36%) with a significant difference between the case-hospital (2.9%) and the control-group (0.8%) (P value <0.001). There was a wide variation in the positivity rate between regions and/or cities in Saudi Arabia, ranging from 0% to 6.31%. Of the serology positive samples, 100 samples were further tested using the SAS2pp neutralization assay; 92 (92%) samples showed neutralization activity. The seropositivity rate in Kingdom of Saudi Arabia is low and varies across different regions with higher positivity in case-hospitals than control-hospitals. The lack of neutralizing antibodies (NAb) in 8% of the tested samples could mean that assay is a more sensitive assay or that neutralization assay has a lower detection limits; or possibly that some samples had cross-reaction to spike protein of other coronaviruses in the assay, but these were not specific to neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)

Knowledge, attitude and compliance of infection control guidelines among dental faculty members and students in KSU

Abstract Background Infection is one of the most crucial problems in health care services worldwide. It is considered one of the most important causes of morbidity and mortality associated with clinical, diagnostic and therapeutic procedures. Therefore, the purpose of this study was to investigate knowledge, attitude, and compliance with recommended infection control guidelines among dental faculty members and students at King Saud University, Riyadh, Kingdom of Saudi Arabia. Methods A cross-sectional study was conducted to obtain information regarding knowledge, attitude, and compliance with recommended infection control guidelines. The sample (n = 317) comprised of dental faculty members and students (3rd, 4th and 5th year) in both male and female campuses of College of Dentistry (KSU). This questionnaire contained three parts (knowledge, attitude, and compliance) and was distributed to the participants. After validation of the survey, data were collected, entered and analyzed by SPSS software. Results A total of 317 dental faculty members and students participated in this study. Out of the total study subjects, 141 (44.5%) were female and 176 (55.5%) were male. A comparison between dental faculty members and students was made based on their knowledge, attitude, and compliance, which resulted in almost equal percentages of knowledge (49.6, 49.0% respectively). In addition, it revealed that faculty members’ attitude toward infection control in the dental clinic was more positive compared to their compliance with the infection control guidelines (70.6, 65.2% respectively) while with the students it was vice versa (67.2, 69.6% respectively). There is no statistically significant difference in the knowledge and attitude of dental faculty members and students regarding infection control guidelines (P > 0.05). Conclusion Our study showed that dental undergraduate student and faculty members at KSU demonstrated a good adherence to infection control guidelines. On the other hand, there was a lack in the knowledge of the basics of infection control standards

The value of assessing case difficulty and its effect on endodontic iatrogenic errors: A retrospective cross-sectional study

The American Association of Endodontists (AAE) released a case difficulty assessment form to help general dentists and students treat cases within their expertise or refer advanced cases to reduce the risk of iatrogenic errors. The purpose of this study was to determine the incidence of iatrogenic complications after the use of the case difficulty assessment form. A random sample of 1000 cases that received root canal treatment in undergraduate clinics during the academicyear (2016–2017) was selected. Case difficulty assessment was made for each case before treatment onset. Once the case was approved for treatment in the undergraduate clinics, the endodontic treatments were performed following the standard procedure the endodontic department of the Dentistry School of King Abdulaziz University mandates. Digital radiographs were obtained during routine root canal treatment and were evaluated by four observers to detect any iatrogenic errors, after which the data were analyzed statistically. Iatrogenic errors were correlated significantly with case difficulty (p= 0.003), and were detected in 22.1% of all teeth treated in the undergraduate clinics. Underfilling accounted for the highestpercent of errors detected (8.4%), followed by ledge formation (4.2%). Molar teeth had the highest frequency of errors, and mesio-buccal roots of maxillary molars showed the highest percentage of errors. The AAE developed a significantly useful tool to determine the difficulty of each case treated in undergraduate clinics, and following their recommendations will minimize the risk of iatrogenic errors

Mitochondrial DNA haplogroup analysis in Saudi Arab patients with multiple sclerosis.

Previous studies have suggested that mitochondrial DNA (mtDNA) variants are associated with multiple sclerosis (MS), a complex neurodegenerative immune-mediated disease of the central nervous system. Since mtDNA is maternally inherited without recombination, specific mtDNA variants defining genetic background are associated with the susceptibility to human diseases. To assess the contribution of mtDNA haplogroups to the predisposition of MS in an Arab population, we analysed sequencing data of mitochondrial genomes from 47 native Saudi Arab individuals including 23 patients with relapsing-remitting MS (RRMS) and 24 healthy controls. All patients and controls could be classified into ten haplogroups. The European-specific haplogroup U was more prevalent in patients than in the controls (26.1% vs. 4.2%), whereas haplogroup T was only present in patients and haplogroups HV and N were only found in controls. Haplogroup U was significantly association with increased risk of MS (odds ratio = 6.26, p0.05). Definition site of haplogroup U include the variant m.12308A>G in MT-TL2 gene which was found to affect highly conserved position within the variable arm of tRNALeu(CUN) and thus may impact mitochondrial protein synthesis, and two other variants namely m.11467A>G in MT-ND4 gene and m.12372G>A in MT-ND5 gene which were previously linked with mitochondrial function. Despite the small number of subjects, which may limit the statistical power of the study, our results showed for the first time a possible contribution of haplogroup U to the predisposition to MS in an Arab population. These findings warrant further validation in a large cohort to distinguish a genuine effect specific to MS from a chance finding due to small sampling

eHomeCaregiving: A Diabetes Patient-Centered Blockchain Ecosystem for COVID-19 Caregiving

The pandemic has triggered an unprecedented global demand for home caregiving to manage asymptomatic and mild COVID-19 cases. Older people and others with pre-existing medical conditions (including diabetes) appear to be more vulnerable to severe illness caused by the severe acute respiratory syndrome coronavirus 2. Approximately 25% of Saudis suffer from diabetes; these 4 million patients require 5.5 million consultations and follow-up visits each year to manage their disease. Furthermore, with the increasing number of patients with diabetes and their need for professional care, it is difficult and time consuming to share patient-care information among caregivers in a traditional way; this increases the financial and psychological burden of home caregivers. Although the pandemic has also triggered a global demand for digital health technology adoption worldwide to achieve higher standards of health, recent developments in advanced technologies and mobile health (mHealth) applications have failed to equip the caregivers with the right ecosystem for patient-centered information sharing to allow for informed care decisions. Therefore, there is a gap in the literature as the current solutions fall short of facilitating an effective communication channel among caregivers and between them and their patients, supporting diverse caregiving groups with multiple languages, distributing tasks between caregivers to alleviate the burden on one caregiver, providing a treatment plan by a specialized care team to be viewed and followed by caregivers and patients, and alerting everyone in case of an emergency. Based on the need for empowering home caregivers to cope with the pressure, we propose eHomeCaregiving, an mHealth solution that can build a transparent blockchain-based patient-centered family caregiving ecosystem. eHomeCaregiving facilitates care continuity in patients with type 2 diabetes in Saudi Arabia by integrating care, saving time and efforts of all caregivers, and improving the patient’s quality of life and outcomes, particularly in terms of facing emerging challenges amid the pandemic

Simultaneous Action of Silymarin and Dopamine Enhances Defense Mechanisms Related to Antioxidants, Polyamine Metabolic Enzymes, and Tolerance to Cadmium Stress in Phaseolus vulgaris

Silymarin (Sm) and dopamine (DA) act synergistically as potential antioxidants, mediating many physiological and biochemical processes. As a first report, we investigated the synergistic effect of Sm and DA in mitigating cadmium stress in Phaseolus vulgaris plants. Three experiments were conducted simultaneously using 40 cm diameter pots to elucidate how Sm and DA affect cadmium tolerance traits at morphological, physiological, and biochemical levels. Cadmium stress triggered a marked reduction in growth, productivity, and physio-biochemical characteristics of common bean plants compared to unstressed plants. Seed priming (SP) and foliar spraying (FS) with silymarin (Sm) or dopamine (DA) ((DA (SP) + Sm (FS) and Sm (SP) + DA (FS)) ameliorated the damaging effects of cadmium stress. Sm seed priming + DA foliar spraying (Sm (SP) + DA (FS)) was more efficient. The treated stressed common bean plants showed greater tolerance to cadmium stress by diminishing oxidative stress biomarkers (i.e., O2&bull;&minus;, H2O2, and MDA) levels through enhanced enzymatic (SOD, CAT, POD, APX) and non-enzymatic (ascorbic acid, glutathione, &alpha;-tocopherol, choline, phenolics, flavonoids) antioxidant activities and osmoprotectants (proline, glycine betaine, and soluble sugars) contents, as well as through improved photosynthetic efficiency (total chlorophyll and carotenoids contents, photochemical activity, and efficiencies of carboxylation (iCE) and PSII (Fv/Fm)), polyamines (Put, Spd, and Spm), and polyamine metabolic enzymes (ADC and ODC) accumulation. These findings signify that Sm and DA have remarkable anti-stress effects, which can help regulate plant self-defense systems, reflecting satisfactory plant growth and productivity. Thus, realizing the synergistic effect of Sm and DA in cadmium tolerance confers potential new capabilities for these compounds to function in sustainable agriculture

Antitumor properties of certain spirooxindoles towards hepatocellular carcinoma endowed with antioxidant activity

In the current medical era, spirooxindole motif stands out as a privileged heterospirocyclic scaffold that represents the core for a wide range of bioactive naturally isolated products (such as Strychnofoline and spirotryprostatins A and B) and synthetic compounds. Interestingly, no much attention has been paid to develop spirooxindole derivatives with dual antioxidant and anticancer activities. In this context, a series of spirooxindoles 6a-p was examined for their anticancer effect towards HepG2 hepatocellular carcinoma and PC-3 prostate cancer cell lines. Spirooxindole 6a was found to be an efficient anti-proliferative agent towards both HepG2 and PC-3 cells (IC50 = 6.9 and 11.8 µM, respectively). Afterwards, spirooxindole 6a was assessed for its apoptosis induction potential in HepG2 cells, where its pro-apoptotic impact was approved via the significant elevation in the Bax/Bcl-2 ratio and the expression levels of caspase-3

Novel Diamide-Based Benzenesulfonamides as Selective Carbonic Anhydrase IX Inhibitors Endowed with Antitumor Activity: Synthesis, Biological Evaluation and In Silico Insights

In this work, we present the synthesis and biological evaluation of novel series of diamide-based benzenesulfonamides 5a&#8722;h as inhibitors of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) isoforms hCA I, II, IX and XII. The target tumor-associated isoforms hCA IX and XII were undeniably the most affected ones (KIs: 8.3&#8722;123.3 and 9.8&#8722;134.5 nM, respectively). Notably, diamides 5a and 5h stood out as a single-digit nanomolar hCA IX inhibitors (KIs = 8.8 and 8.3 nM). The SAR outcomes highlighted that bioisosteric replacement of the benzylidene moiety, compounds 5a&#8722;g, with the hetero 2-furylidene moiety, compound 5h, achieved the best IX/I and IX/II selectivity herein reported with SIs of 985 and 13.8, respectively. Molecular docking simulations of the prepared diamides within CA IX active site revealed the ability of 5h to establish an additional H-bond between the heterocyclic oxygen and HE/Gln67. Moreover, benzenesulfonamides 5a, 5b and 5h were evaluated for their antitumor activity against renal cancer UO-31 cell line. Compound 5h was the most potent derivative with about 1.5-fold more enhanced activity (IC50 = 4.89 &#177; 0.22 &#956;M) than the reference drug Staurosporine (IC50 = 7.25 &#177; 0.43 &#956;M). Moreover, 5a and 5h were able to induce apoptosis in UO-31 cells as evidenced by the significant increase in the percent of annexinV-FITC positive apoptotic cells by 22.5- and 26.5-folds, respectively