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This study holistically examines the status quo of learner-on-learner bullying in South African schools. An exposition is given pertaining to inter alia constitutional law, common law, statutory provisions and case law. Since bullying is a global problem, a legal comparative study is necessary in order to place the phenomenon of bullying into context. Concepts such as bystander behaviour, bullycide and restorative justice feature prominently in this dissertation. Important findings include the necessity of drafting of anti-bullying legislation as well as the inception of bullycide as a statutory crime. Furthermore, restorative justice processes are critically important to not only rehabilitate and reintegrate the bully, but also to vindicate the victim in a way that protects and promotes the rights of all parties involved. Recommendations are made with regard to the importance of a national anti-bullying policy to be implemented in conjunction with existing codes of conduct. / Dissertation (LLM)--University of Pretoria, 2012. / Private Law / unrestricted

Pancreatic cancer (PC) is a highly aggressive disease with unmet therapeutic needs. Recent advances in the use of oncolytic viruses (OVs) as cancer therapeutic agents bring new hope to fight the notorious disease that is PC. Although OVs have shown promising results in certain cancers, some tumors remain resistant to OV therapy due to their inherent residual antiviral mechanisms. We hypothesized that the use of OV-encoded artificial microRNAs (amiRNAs) could help target the cellular antiviral components associated with the observed OV resistance and could also sensitize neighboring tumor cells to OV therapy and small molecule inhibitors through the secretion of amiRNA-containing extracellular vesicles (EVs) from infected cells. To find such amiRNAs, a viral surrogate library encoding ~16,000 unique amiRNAs was passaged in pancreatic cancer cell lines to enrich for sequences that could enhance OV replication. An amiRNA that improves PC cell killing when expressed from an OV was identified. Target identification of this amiRNA (amiR-4) revealed ARID1A as a key player in resistance to OV therapy in pancreatic cancers. This target is of particular interest, since its downregulation acts in a synthetic lethal fashion with inhibition of the EZH2 methyltransferase. Combining VSV51-amiR-4 with a small molecule inhibitor of EZH2 enhances PC cell death. Moreover, amiR-4 is packaged in cancer cell-secreted EVs which can reach neighboring naïve cells to sensitize them to EZH2 inhibition-mediated cell death and to spread the OV-mediated tumor killing effect throughout the tumor. This data translates into tumor debulking and survival in animal models of highly aggressive PC. This work not only broadens our knowledge on the resistance of select tumors to oncolytic virotherapy and the EV-mediated bystander killing effect in OV-infected tumors, but it also establishes OVs as a novel tool to produce anti-cancer therapeutic EVs in situ to improve therapeutic gain. Ultimately, our work provides new hope for a cure to the grim disease that is PC.

The collective nature of group affiliation may inhibit an individual from exhibiting prosocial behavior regarding acts of religiously-motivated terror. This study's purpose was to investigate the nature of bystander intervention as it relates to religious group affiliation. Darley and Latane's bystander effect theory provided the theoretical framework for this study. The research questions examined the impact of religious group affiliation and group size on the dependent variables of civic moral disengagement (CMD) and commitment to the war on terror (CWT). Three validated survey instruments were administered to a random participant pool of 206 respondents. An ANCOVA and Spearman's rho correlation were employed to address the research questions. Findings revealed that neither religious group affiliation nor group size significantly predicts either CWT or CMD after controlling for the degree of religious commitment. Further research should test alternative theories associated with leadership and group dynamics. Positive social change is advanced by acknowledging that bystanders to acts of terrorism may not be influenced by factors such as group affiliation or size of religious group affiliations. These findings underscore the complexity of the relationship between behavior and religious affiliation. Policy makers and future researchers may benefit by redirecting their focus for prevention and intervention toward influences such as the motivational dynamic between religious leaders and their followers.

School bullying has become a serious issue in U.S. schools, with children being harassed, hurt, and even killed or driven to suicide or homicide as a result of being bullied. Bullying in schools has persisted despite the various intervention measures taken to curtail the phenomenon. The purpose of this phenomenological exploration was to explore how teachers and principals at a U.S. middle school perceive the school's existing bullying programs and elicit recommendations about how to improve the programs. The theoretical basis of this investigation was Bandura's social learning theory. Data were collected through interviews with 4 principles and 6 teachers. Interview data were transcribed, and then coded and analyzed using a modified Van Kaam procedure, as revised by Moustakas. Nine themes emerged from the data analysis that encompassed participants' perceptions of the causes of bullying and how teachers and principals can help to prevent bullying. The key finding is that teachers reported that more professional training to reduce bullying is needed. Additionally, social learning theory is explanatory of participant experiences as they noted that encouraging positive behavior, kindness, and empathy in the classroom will help minimize bullying conduct in schools. This study may foster societal change by providing insight to educational leaders about how to improve antibullying programs, which may lead to reductions in school dropout rates, incidents of homicide and suicide as a result of school bullying, and other antisocial behaviors associated with school bullying.

Being the victim of school bullying is associated with many negative outcomes, including depression, anxiety, substance abuse, school refusal, and suicide. Peer bystanders are present in the majority of bullying situations and bystander intervention has been found to be very important in ending a bullying incident. However, most of the time bystanders do not step in to help the victim. The present study investigated the impact of parent and family influences on children’s bystander behavior. Seventy-three third- through sixth-grade students were given a questionnaire that asked about their behavior in bullying situations (engaging in bullying behavior, helping or encouraging the bully, defending the victim, or staying away from the situation altogether). Their mothers completed three questionnaires that evaluated symptoms of depression, quality of the parent-child relationship, and parent responses and experiences of anger. Key findings were: (a) parents who were more frustrated with their relationship with their children had children who were less likely to help their peers and were more likely to stay out of the incident. (b) children whose parents were less satisfied with their school were more likely to engage in bullying behavior; (c) the way parents expressed and controlled their own anger predicted whether or not their child would defend a peer; and (d) older children were both more likely to defend their peers and more likely remain uninvolved.

Ethnic minorities often experience microaggressions that cause psychological distress and increase health risks. Bystander interventions are good ways to intervene when microaggressions take place and provide emotional support for ethnic minority targets. White interveners and interventions that pose low threats to White aggressors are perceived more positively than ethnic minority interveners and interventions that are more confrontational and direct. Furthermore, a support-based intervention that validates White aggressors’ good intention and effort without judgement may help White aggressors feel less defensive and more receptive to the intervention. Asian Americans face unique microaggressive themes and their racial experiences are influenced by the stereotype that they are model minorities. Asian Americans may prefer the supportive interventions because they are congruent with Asian cultural values such as relational harmony. The current set of studies assessed the effect of different intervention formats (high threat, low threat, support based) and race of interveners (Asian vs. White) on Asian American targets and White witnesses’ emotional change, perceptions of the intervention, and willingness for future interracial interactions. Among three intervention formats, Asian American targets perceived the intervener and aggressor least negatively in the support intervention. Asian American targets perceived the intervener least positively, whereas White witnesses perceived intervener most negatively in the high-threat intervention. White witnesses perceived the intervener more positively and had more interests in making friends with them when they are White than Asian in high-threat and supportive interventions. White witnesses’ favorable perceptions of aggressor were only influenced by a high degree of racial colorblindness. Overall, the support approach seems to be the most socially appropriate and accepting bystander intervention strategy to intervene in microaggressions targeted at Asian Americans. The high-threat approach is likely to damage interveners’ social image, especially when the intervener is Asian.

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The effects of low doses of ionizing radiation on living things is a continually evolving area of research. Importantly, low dose effects were historically overlooked and not properly accounted for the assessment of risk to human health, as is the case with the contentious linear no-threshold model. These low dose effects are now known to be relevant to human health in both accidental and intentional exposures, including doses relevant to medical diagnostics and therapeutics. Furthermore, there is a relative dearth of information on low dose effects in non-human species, which necessitates further investigation and evaluation of radiosensitivity. Radiation-induced bystander effects occur in organisms due to the receipt of signals from directly irradiated cells, which act to communicate radiation damage to surrounding cells. Recent research has identified one type of bystander signal which is carried by photons of biological origin, however the effects produced in bystander cells receiving these photons has not been extensively investigated. It was suspected, based on previous research, that reactive oxygen species participate in the manifestation of this bystander effect. Three mammalian cell lines were assessed for their ability to produce bystander photons upon direct irradiation; subsequently, radiologically unexposed cells were exposed to the resulting photons and assayed for biological effects. The human cell lines used exhibited significant photon emissions and oxidative stress, clonogenic cell death, reduced cellular metabolism, and compromised mitochondrial oxidative phosphorylation following exposure to these photons. The use of a melanocyte cell line indicated that these effects are attenuated by melanin, and this is suspected to occur through photoabsorption or antioxidant mechanisms. Additionally, the same assays were conducted following cell exposure to hydrogen peroxide at low concentrations to assess responses to oxidative stress relevant to bystander responses, indicating less overall sensitivity in the examined melanocytes. These findings are significant because they contribute to our understanding of the mechanisms behind low dose biological effects, because they further challenge the linear no-threshold model and other models based on target theory, because they provide evidence for differential responses to the physical bystander signal in non-human species, and because secondary photon emissions are likely relevant to the medical radiation sciences. / Thesis / Master of Science (MSc) / Low doses of ionizing radiation interact with living things differently than high doses. Low dose effects are now known to be relevant to human health and protection of the environment. Radiation-induced bystander effects occur in cells due to the receipt of signals from irradiated cells which act to communicate radiation damage to surrounding cells. One type of bystander signal is carried by photons emitted from directly irradiated cells, however the effects produced in bystander cells receiving these photons has not been extensively investigated. This thesis investigates the cellular effects of these “biophotons”, including cell survival, oxidative stress, and metabolism.

The historical narrative and our understanding about the low dose effects of radiation on the immune system has changed drastically from the beginning of the 20th century to now. A paradigm shift from the DNA target hit model to the one that also considers non-targeted effects (NTE) has attracted a lot of interest recently. Investigations to delineate mechanisms of NTE in the biological tissue have been carried out by various research groups where radiation induced genomic instability (RIGI), bystander effect (RIBE) and abscopal effect (AE) are the effects with most evidence available. This thesis addresses the question of whether low dose ionizing radiation (LDIR) stimulates or suppresses the immune system and how NTEs contribute to this immune modulation by adopting a two-pronged approach where first a narrative review constituting the introduction and literature review was performed followed by a systematic review using PRISMA guidelines to synthesize existing LDIR literature. This was prompted by our recent discovery that UVA photons are emitted by the irradiated cells and that these photons can trigger bystander effects in unirradiated recipients of these photons. Given the well-known association between UV radiation and the immune response, where these biphotons may pose as bystander signals potentiating processes in deep tissues as a consequence of ionising radiation, it is timely to revisit the field with a fresh lens. After reviewing various pathways and immune components that contribute to the beneficial and adverse effects induced by LDIR, it was found that these modulations can occur by way of NTE. However, the exact mechanistic underpinnings are still unclear and the literature examining low to medium dose effects of ionising radiation on the immune system is complex and controversial. Early work was compromised by lack of good dosimetry while later work mainly focuses on the involvement of immune responses in radiotherapy which typically uses high dose radiation. There is a lack of research in the LDIR/NTE field focussing on immune responses although bone marrow stem cells and lineages were critical in the identification and characterisation of NTE. This may be in part, a result of the difficulty of isolating NTE in whole organisms which are essential for good immune response studies. Models involving inter organism transmission of NTE are a promising route to overcome these issues. It is concluded that the simple question of whether LDIR stimulates or suppress the immune system is not as simple as initially hypothesized. An attempt was made to analyze if LDIR shifts the balance to immune suppression or enhancement via systematic review but, due to too many differences in the experimental methods in the current radiation and immune studies, a cookie-cutter answer was not possible. However, this thesis did point out the areas of concern such as lack of standardised tools in the field of radiobiological experimental research and quality of methods used which requires urgent attention. / Thesis / Master of Science (MSc)