Exploring the characteristics of abusive behaviour in online social media settings

Online abusive behaviour can impact interaction amongst contributors and moderators. It may lead to physical harm or threats. Existing research has not addressed the perception of moderation activity, discussion and disagreement can cause contributors to react aggressively. This thesis investigates the factors that lead to abusive behaviour in conversations within online settings. In particular, empirical analyses were conducted to identify the factors that contribute to abuse in online settings and to distinguish between polite and abusive forms of disagreement. Three contributions were presented in this research to address each to social computing, computational social science and cyber abuse research domains. The analyses suggested that moderators on Reddit view themselves as members of their community and work hard to both guard against violations, but also with contributors to enhance the quality of their content. Moderators also reported the nuances that distinguish polite and abusive disagreement. Furthermore, the analyses revealed that the differences between in-person and online conversations can help identify abusive behaviour. Specifically, the setting of discussion fosters participant behaviours (less hedging, more extreme sentiment, greater willingness to express personal opinion and straying from topic) that are known to increase the likelihood of abusive behaviour. Additionally, the findings revealed how consensus-building factors can influence disagreement in different settings. Finally, we showed how disagreement can be identified and can affect votes based on linguistics contexts. It was shown that different forms of disagreement can be detected better when using specific abuse, politeness and sentiment textual features using models of multi label text classification. The above research findings conceptualised the development of moderation systems to combat online abusive behaviour, based on analysis of the type of disagreement a contribution embodies and other linguistic and behavioural characteristics

Performance Evaluation of Insoluble Surfactants on the Behavior of Two Electric Layers

The purpose of this study is to establish the effects of insoluble surfactants on the stability of two layers flow down an inclined wall in the limit of Stokes and long-wavelength approximations. The dynamics of the liquid-liquid interface is described for arbitrary amplitudes by evolution equations derived from the basic hydrodynamic equations, in which the fluids are subjected to a uniform electric field. The principle aim of this work is to investigate the interfacial stability as well as the growth rate in the presence of insoluble surfactants. The parameters governing the flow system, such as Marangoni, Weber, capillary numbers and the inclined substrate strongly affect the waveforms and their amplitudes and hence the stability of the fluid. Approximate solutions of this system of linear evolution equations are performed. epending on the selected parameters, the phenomenon of the dual role is found with respect to the electric Weber number as well as the viscosity ratio. The interfacial waves will be more stable due to the growth of the Marangoni number while, while the opposite effect is found for the increase in capillary number. In the longwave perturbations, the stability process is found to confirm the stabilizing effect of the Marangoni number and the destabilizing influence of both capillary and Reynolds numbers, whereas the dual role is observed for the dielectric ratio

Autozygome-guided exome sequencing in retinal dystrophy patients reveals pathogenetic mutations and novel candidate disease genes

Retinal dystrophy (RD) is a heterogeneous group of hereditary diseases caused by loss of photoreceptor function and contributes significantly to the etiology of blindness globally but especially in the industrialized world. The extreme locus and allelic heterogeneity of these disorders poses a major diagnostic challenge and often impedes the ability to provide a molecular diagnosis that can inform counseling and gene-specific treatment strategies. In a large cohort of nearly 150 RD families, we used genomic approaches in the form of autozygome-guided mutation analysis and exome sequencing to identify the likely causative genetic lesion in the majority of cases. Additionally, our study revealed six novel candidate disease genes (C21orf2, EMC1, KIAA1549, GPR125, ACBD5, and DTHD1), two of which (ACBD5 and DTHD1) were observed in the context of syndromic forms of RD that are described for the first time

Global wealth disparities drive adherence to COVID-safe pathways in head and neck cancer surgery

Peer reviewe

Effect of Utility Cut Patching on Pavement Deterioration

Utility Cut Patching (UCP) is a major cause of pavement deterioration in city streets. The streets of the city of Riyadh are no exception. A study was undertaken to investigate factors related to UCP and possibly contributing to pavement deterioration. Existing pavement condition, materials properties of patch and pavement, and geometry of trench were among factors investigated. Pavement deterioration was evaluated by deflection measurements at various points on the patch and existing pavement using falling weight deflectometer. Analysis of the results indicated that deflection at center of patch is the most critical one. Furthermore, deflection readings at various points on the patch indicated the dependency of patch deflection on trench geometry and existing pavement structural conditions. Investigation of patching effects on pavement roughness suggested an increase in roughness of pavement due to UCP

Effect of Utility Cut Patching on Pavement Deterioration

Utility Cut Patching (UCP) is a major cause of pavement deterioration in city streets. The streets of the city in Riyadh are no exception. A study was undertaken to investigate factors related to UCP and possibly contributing to pavement deterioration. Existing pavement condition, materials properties of patch and pavement, and geometry of trench were among factors investigated. Pavement deterioration was evaluated by deflection measurements at various points on the patch and existing pavement using falling weight deflectometer, Analysis of the results indicated that deflection at center of patch is the most critical one. Furthermore, deflection readings at various points on the patch indicated the dependency of palthdeflection on trenchgeometry and existing pavement structural conditions. Investigation of patching effects on pavement roughness suggested an increase in roughness of pavement due to UCCorresponding Author: Prof. Abdulrahman Saleh Al-Suhaibani, Department of Civil Engineering, College of Engineering, King Saud University,P.O. Box 800, Riyadh 11421 Saudi Arabia. Email: [email protected]

The Impact of the COVID-19 Pandemic on Ophthalmic Outpatient Care in a Tertiary Care Center in Riyadh

In this paper, we measured the impact of a full COVID-19 lockdown on ophthalmic patients after a period of lockdown in Saudi Arabia, from March to September 2020. A cross-sectional analytical study was carried out on 180 patients who had their appointments delayed or canceled due to the lockdown. Data was collected from electronic medical records and patients via voice calls using a validated questionnaire that were analyzed using a multivariable binary regression analysis. The results show no statistically significant mean difference in visual acuity when comparing pre- and post-lockdown measurements. The median number of appointment cancellations/delays per patient was two, and the estimated delay for the first canceled appointments was equal to 178.8 days. Of the cohort studied, 15.4% of patients faced delays in necessary surgical and therapeutic interventions; 22.1% of patients sought eye care at other institutions due to the delay, and 15% of those were seen by doctors unspecialized in ophthalmology. The odds of dissatisfaction with care were higher in patients who experienced cancellations in a surgical procedure and patients who experienced difficulty in obtaining medications. In conclusion, the pandemic hampered ophthalmic patients’ access to medications. Subjective visual outcomes of patients were also negatively affected; however, the change in objective visual parameters was not statistically significant

The outcomes and prognostic factors of vitrectomy in chronic diabetic traction macular detachment

Muneera A Abunajma,1 Hassan Al-Dhibi,1 Emad B Abboud,1 Yahya Al Zahrani,1 Essam Alharthi,2 Abdullah Alkharashi,3 Nicola G Ghazi1,4 1Vitreoretinal Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia; 2Al Hokama Eye Center, Riyadh, Saudi Arabia; 3Department of Ophthalmology, College of Medicine, King Saud University Riyadh, Saudi Arabia; 4Department of Ophthalmology, University of Virginia, Charlottesville, VA, USA Purpose: To investigate the outcomes of pars plana vitrectomy (PPV) for chronic diabetic traction macular detachment (CTMD).Methods: Ninety-six eyes that underwent PPV for CTMD of at least 6 months duration were retrospectively analyzed. Retinal reattachment rate, final vision, and prognostic factors for poor visual outcome were the main outcome measures.Results: All eyes had long-standing TMD (median 12, range: 6–70 months). The median postoperative follow-up was 15 (range: 3–65) months. Eighty-seven eyes (90.6%) had their retina and macula reattached after one PPV. At final examination, 84 eyes (87.5%) had stable vision or at least one line improvement, and three had no light perception. Seventeen (17.7%) and 41 (43%) eyes had preoperative visual acuity of ≥20/200 and ≥5/200 as compared to 40 (41.6%; P=0.0005) and 64 (66.7%; P=0.0014) eyes at final follow-up, respectively. Age >50 years (Odds ratio [OR] =5.84, 95% confidence interval [CI] =1.53–22.19, P=0.01), preoperative vision <20/400 (OR =7.012, 95% CI =1.82–26.93, P=0.005), and ischemic macula (OR =14.13, 95% CI =3.61–55.33, P<0.001) were significantly associated with final vision <20/400.Conclusion: PPV for CTMD may be beneficial particularly in patients who are relatively younger and have good baseline vision and no macular ischemia. Keywords: chronic diabetic traction macular detachment, diabetic retinopathy, diabetic traction macular detachment, pars plana vitrectom

IL-17/Notch1/STAT3 Pathway Contributes to 5-Fluorouracil-Induced Intestinal Mucositis in Rats: Amelioration by Thymol Treatment

5-Fluorouracil (5-FU) is an anticancer drug with intestinal mucositis (IM) as a deleterious side effect. Thymol is a monoterpene phenol which has been reported to possess an antioxidant and anti-inflammatory activity versus 5-FU-induced IM. The Notch pathway affects multiple cellular activities, such as cellular proliferation, in addition to inflammatory responses modulation. Accordingly, this work was carried out in order to elucidate the role of the Notch pathway in 5-FU-induced IM and to further elucidate the immunomodulatory protective mechanisms of thymol. Experimental rats were divided randomly into four groups: Control, 5-FU, 5-FU+thymol (60 mg/kg/day), and 5-FU+thymol (120 mg/kg/day). 5-FU was injected intraperitoneally at a dose of 150 mg/kg on days 6 and 7, while thymol was orally administered daily for 11 days. By the end of the study, intestinal tissues were collected for the determination of IL-17, CD4, CD8, Notch1, Hes-1, pSTAT3, and STAT-3 protein expressions. The effect of thymol on 5-FU cytotoxicity was also examined using WST1 assay. 5-FU induced a marked increase in IL-17 levels, along with a marked downregulation of CD4 and the upregulation of CD8, Notch1, Hes-1 protein expressions, and activation of STAT3 in the intestinal tissue when compared with the control group. Thymol ameliorated the changes that occurred in these parameters. Additionally, cytotoxicity testing revealed that thymol augmented the antiproliferative action of 5-FU against breast and colorectal human cancer cell lines. This study was the first to show that the IL-17/Notch1/STAT3 pathway is involved in the molecular mechanism of 5-FU-induced IM, as well as the immunomodulatory activity of thymol

Exposure to Methylmercury at Juvenile Stage Worsens Autism-like Symptoms in Adult BTBR T+tf/J Mice Due to Lack of Nuclear Factor Erythroid 2-Related Factor 2 Signaling Upregulation in Periphery and Brain

Autism spectrum disorder (ASD) is a multifaceted developmental condition that first appears in infancy. The condition is characterized by recurrent patterns in behavior and impairments in social and vocalization abilities. Methylmercury is a toxic environmental pollutant, and its derivatives are the major source of organic mercury to human beings. Inorganic mercury, which is released from a variety of pollutants into oceans, rivers, and streams, is transformed into methylmercury by bacteria and plankton in the water, which later builds up in fish and shellfish, and then enters humans through the consumption of fish and shellfish and increases the risk of developing ASD by disturbing the oxidant–antioxidant balance. However, there has been no prior research to determine the effect of juvenile exposure of methylmercury chloride on adult BTBR mice. Therefore, the current study evaluated the effect of methylmercury chloride administered during the juvenile stage on autism-like behavior (three-chambered sociability, marble burying, self-grooming tests) and oxidant–antioxidant balance (specifically Nrf2, HO-1, SOD-1, NF-kB, iNOS, MPO, and 3-nitrotyrosine) in the peripheral neutrophils and cortex of adult BTBR and C57BL/6 (B6) mice. Our results show that exposure to methylmercury chloride at a juvenile stage results in autism-like symptoms in adult BTBR mice which are related to a lack of upregulation of the Nrf2 signaling pathway as demonstrated by no significant changes in the expression of Nrf2, HO-1, and SOD-1 in the periphery and cortex. On the other hand, methylmercury chloride administration at a juvenile stage increased oxidative inflammation as depicted by a significant increase in the levels of NF-kB, iNOS, MPO, and 3-nitrotyrosine in the periphery and cortex of adult BTBR mice. This study suggests that juvenile exposure to methylmercury chloride contributes to the worsening of autism-like behavior in adult BTBR mice through the disruption of the oxidant–antioxidant balance in the peripheral compartment and CNS. Strategies that elevate Nrf2 signaling may be useful to counteract toxicant-mediated worsening of ASD and may improve quality of life