The concept of strong and weak virtual reality

We approach the virtual reality phenomenon by studying its relationship to set theory, and we investigate the case where this is done using the wellfoundedness property of sets. Our hypothesis is that non-wellfounded sets (hypersets) give rise to a different quality of virtual reality than do familiar wellfounded sets. We initially provide an alternative approach to virtual reality based on Sommerhoff's idea of first and second order self-awareness; both categories of self-awareness are considered as necessary conditions for consciousness in terms of higher cognitive functions. We then introduce a representation of first and second order self-awareness through sets, and assume that these sets, which we call events, originally form a collection of wellfounded sets. Strong virtual reality characterizes virtual reality environments which have the limited capacity to create only events associated with wellfounded sets. In contrast, the more general concept of weak virtual reality characterizes collections of virtual reality mediated events altogether forming an entirety larger than any collection of wellfounded sets. By giving reference to Aczel's hyperset theory we indicate that this definition is not empty, because hypersets encompass wellfounded sets already. Moreover, we argue that weak virtual reality could be realized in human history through continued progress in computer technology. Finally, we reformulate our characterization into a more general framework, and use Baltag's Structural Theory of Sets (STS) to show that within this general hyperset theory Sommerhoff's first and second order self-awareness as well as both concepts of virtual reality admit a consistent mathematical representation.Comment: 17 pages; several edits in v

Intraoperative magnetic resonance imaging-assisted transsphenoidal pituitary surgery in patients with acromegaly

In this largest study to date of GH-producing pituitary adenomas in which iMR imaging-guided transsphenoidal surgery was analyzed, the results suggest that this method is a highly effective and safe treatment modality, even compared with previously published surgical series in which high-field iMR imaging was used. Limitations of iMR imaging are the detection of small residual tumor in the cavernous sinus and persisting disease that could not be observed, even on diagnostic high-field follow-up MR images. This points to a general limitation regarding remission rates that can be achieved using iMR imaging. Nevertheless, iMR imaging led to an increase of the remission rate in this study

Extensive spherical amyloid deposition presenting as a pituitary tumor

A 71-yr-old man was admitted for further evaluation and trans-sphenoidal surgery of a pituitary tumor. He complained of impotence and decreased libido over a period of about 40 yr. Thirty-eight yr ago he was treated for bilateral gynecomastia with galactorrhea. Endocrinological investigation at presentation revealed only mild hyperprolactinemia and hypogonadotropic hypogonadism. Pituitary magnetic resonance imaging (MRI) showed a tumor up to 2.5 cm in diameter with infiltration of the sphenoid sinus and right cavernous sinus. The tumor exhibited a heterogeneous hyperintense signal on T1-weighted images and hypointense signal on T2-weighted images. Standard trans-sphenoidal surgery was performed and a brownish mass was found inside the sella, which was removed. Histological examination of the mass revealed extensive spherical amyloid deposits with strongly positive immunohistochemical staining for prolactin. Therefore, a prolactinoma with extensive spherical amyloid deposition was diagnosed. Extensive spherical amyloid deposition is a rare finding in prolactin-secreting pituitary adenomas. So far, characteristic radiological findings by MRI have been described only twice. Due to characteristic MRI findings, the diagnosis of extensive intrasellar amyloid deposition can be entertained pre-operatively. Trans-sphenoidal surgical resection is essential to confirm the diagnosis histologically and because of the potential lack of tumor shrinkage under dopaminagonist therapy in this type of prolactinom

Antibiotic-Impregnated Versus Silver-Bearing External Ventricular Drainage Catheters: Preliminary Results in a Randomized Controlled Trial

Background: Evaluation of antibiotic-impregnated (AI) and ionized silver particle coated external ventricular drainage catheters (EVD) in patients with subarachnoid (SAH) or intracranial hemorrhage (ICH). Methods: Between February 2011 and June 2012, 40 patients with acute hydrocephalus due to SAH, ICH or intraventricular hemorrhage were enrolled in a prospective, randomized, mono-center pilot study. Primary endpoints were defined as: number of events of cerebrospinal fluid (CSF) infections. Secondary endpoints were defined as: neurosurgical complications following the placement of the EVD, number of revisions of EVD catheters, and cost effectiveness. Results: Sixty-one EVD placements in 40 patients, 32 antibiotic-coated (Bactiseal®), 29 silver-bearing catheters (VentriGuard®), have been performed. Confirmed or high suspicion of CSF infections occurred in 11 out of 61 events (confirmed infection: p=0.71, probable infection: p=0.90). Revisions of EVD were needed in 13 cases (22%) due to CSF infection, dysfunction, impaired healing, or malplacement (p=0.37). Conclusion: Regarding CSF infection rate and dysfunction, no statistical significant differences between the two EVD catheters Bactiseal® versus VentriGuard® were found. The silver-bearing catheter might offer a safe and cost-conscious alternative to the AI cathete

Health, stress, and well-being in Swiss adult survivors of child welfare practices and child labor: Investigating the mediating role of socio-economic factors

BACKGROUND: With widespread deprivation in the education of minors affected by child welfare practices (CWP) in the last century, affected individuals often continued a life dominated by socio-economic disadvantage. According to life course theories, the impact of socio-economic disadvantage can accumulate across the life span, leading to worse health in later life. However, the scientific examination of health correlates of CWP in later life and the mediating role of socio-economic factors (SEF) has previously been neglected. OBJECTIVE: This study examined whether Swiss survivors of CWP, including former Verdingkinder, have poorer health in later life compared to controls, and whether this association is mediated by socio-economic factors: education, income, satisfaction with financial situation, socio-economic status. PARTICIPANTS AND SETTING: Two face-to-face interviews were conducted with N = 257 participants (risk group, RG, n = 132, M$_{AGE}$ = 70.83 years, 58 % male; control group, CG, n = 125, M$_{AGE}$ = 70.6 years, 49 % male). METHODS: A broad set of physical health outcomes, stress, well-being, and SEF were assessed with psychometric instruments. RESULTS: The RG reported more physical illnesses, vascular risk factors, health symptoms, stress, and lower well-being, compared to the CG. Mediation analyses revealed that SEF were relevant mediators for the significant health and stress disparities between groups. CONCLUSIONS: Results suggest that SEF can play a crucial role in mitigating the negative effects and health impairments in individuals formerly affected by CWP. Public health services and policies that target these SEF could improve current welfare practices by providing opportunities to overcome early-life disadvantage and facilitating healthier life trajectories

"Well, not me, but other women do not register because..."- Barriers to seeking antenatal care in the context of prevention of mother-to-child transmission of HIV among Zimbabwean women: a mixed-methods study.

BACKGROUND: While barriers to uptake of antenatal care (ANC) among pregnant women have been explored, much less is known about how integrating prevention of mother-to-child transmission (PMTCT) programmes within ANC services affects uptake. We explored barriers to uptake of integrated ANC services in a poor Zimbabwean community. METHODS: A cross-sectional survey was conducted among post-natal women at Mbare Clinic, Harare, between September 2010 and February 2011. Collected data included participant characteristics and ANC uptake. Logistic regression was conducted to determine factors associated with ANC registration. In-depth interviews were held with the first 21 survey participants who either did not register or registered after twenty-four weeks gestation to explore barriers. Interviews were analysed thematically. RESULTS: Two hundred and ninety-nine participants (mean age 26.1 years) were surveyed. They came from ultra-poor households, with mean household income of US$181. Only 229 (76.6$10-increase in household income 1.02 (95% confidence interval, CI, 1.0-1.04), as was education which interacted with having planned the pregnancy (OR for planned pregnancy with completed ordinary level education 3.27 (95%CI 1.55-6.70). Divorced women were less likely to register than married women, OR 0.20 (95%CI 0.07-0.58). In the qualitative study, barriers to either ANC or PMTCT services limited uptake of integrated services. Women understood the importance of integrated services for PMTCT purposes and theirs and the babies' health and appeared unable to admit to barriers which they deemed "stupid/irresponsible", namely fear of HIV testing and disrespectful treatment by nurses. They represented these commonly recurring barriers as challenges that "other women" faced. The major proffered personal barrier was unaffordability of user fees, which was sometimes compounded by unsupportive husbands who were the breadwinners. CONCLUSION: Women who delayed/did not register were aware of the importance of ANC and PMTCT but were either unable to afford or afraid to register. Addressing the identified challenges will not only be important for integrated PMTCT/ANC services but will also provide a model for dealing with challenges as countries scale up 'treat all' approaches

Manuscript title: Facilitators and barriers to cotrimoxazole prophylaxis among HIV exposed babies: a qualitative study from Harare, Zimbabwe.

BACKGROUND: Implementation of cotrimoxazole prophylaxis (CTX-p) among HIV-exposed infants (HEI) is poor in southern Africa. We conducted a study to investigate barriers to delivery of CTX-p to HEI in Zimbabwe at each step of the care cascade. Here we report findings of the qualitative component designed to investigate issues related to adherence conducted among women identified as HIV positive whose babies were started on CTX-p postnatally. Of note, Zimbabwe also provided nevirapine prophylaxis for HIV exposed babies, so the majority were giving nevirapine and CTX-p to their babies. METHODS: Between Feb-Dec 2011, the first 20 HIV infected mothers identified were invited for in-depth interview 4-5months postnatally. Interviews were recorded, transcribed, translated and analysed thematically. RESULTS: All women desired their baby's health above all else, and were determined to do all they could to ensure their wellbeing. They did not report problems remembering to give drugs. The baby's apparent good health was a huge motivator for continued adherence. However, most women reported that their husbands were less engaged in HIV care, refusing to be HIV tested and in some cases stealing drugs prescribed for their wives for themselves. In two instances the man stopped the woman from giving CTX-p to the baby either because of fear of side effects or not appreciating its importance. Stigma continues to be an important issue. Mothers reported being reluctant to disclose their HIV status to other people so found it difficult to collect prescription refills from the HIV clinic for fear of being seen by friends/relatives. Some women reported that it was hard to administer the drugs if there were people around at home. Other challenges faced were stock-outs of CTX-p at the clinic, which occurred three times in 2011. The baby would then go without CTX-p if the woman could not afford buying at a private pharmacy. CONCLUSIONS: The study highlights that adherence knowledge and desire alone is insufficient to overcome the familial and structural barriers to maintaining CTX-p. Improving adherence to CTX-p among HEI will require interventions to improve male involvement, reduce HIV stigma in communities and ensure adequate supply of drugs

Conceptualisation and psychometric evaluation of positive psychological outcome measures used in adolescents and young adults living with HIV:a mixed scoping and systematic review protocol

Introduction Sub-Saharan Africa bears the greatest burden of HIV. Concomitant mental disorders are common, necessitating the integration of mental healthcare into routine HIV care. Consequently, it is necessary to holistically evaluate the mental health of adolescents and young adults living with HIV (AYALHIV, 10–24 years old) by measuring negative and positive psychological constructs (eg, anxiety and self-acceptance, respectively). There has been a proliferation of positive psychological outcome measures, but the evidence of their psychometric robustness is fragmented. This review, therefore, seeks to (1) identify positive psychological outcomes used in AYALHIV in sub-Saharan Africa and map the constructs onto corresponding measures and (2) critically appraise the psychometrics of the identified outcomes Methods and analysis This mixed review will be done in two parts. First, a scoping review will identify positive psychological outcomes and map them onto corresponding outcome measures. Subsequently, we will systematically evaluate the psychometric properties of the outcomes identified from the scoping review. Independent and blinded reviewers will search articles in PubMed, Scopus, Web of Science, Africa-Wide Information, CINAHL, PsychINFO and Google Scholar from inception through 30 September 2022. Thereafter, separate independent reviewers will screen the retrieved articles. We will apply a narrative synthesis to map the key constructs emerging from the scoping review. For the systematic review, the risk of bias across studies will be evaluated using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist. The quality of the psychometric properties will be rated using the COSMIN checklist and qualitatively synthesised using the modified Grading of Recommendations Assessment, Development and Evaluation checklist. Ethics and dissemination No ethical approvals are needed. The mixed-review outputs will collectively inform the development, implementation and evaluation of bespoke interventions for AYALHIV. Review outcomes will be disseminated in a peer-reviewed journal, on social media and through policy briefs

'This is what is going to help me': Developing a co-designed and theoretically informed harm reduction intervention for mobile youth in South Africa and Uganda

Young migrants in sub-Saharan Africa are particularly vulnerable to HIV-acquisition. Despite this, they are consistently under-served by services, with low uptake and engagement. We adopted a community-based participatory research approach to conduct longitudinal qualitative research among 78 young migrants in South Africa and Uganda. Using repeat in-depth interviews and participatory workshops we sought to identify their specific support needs, and to collaboratively design an intervention appropriate for delivery in their local contexts. Applying a protection-risk conceptual framework, we developed a harm reduction intervention which aims to foster protective factors, and thereby nurture resilience, for youth ‘on the move’ within high-risk settings. Specifically, by establishing peer supporter networks, offering a ‘drop-in’ resource centre, and by identifying local adult champions to enable a supportive local environment. Creating this supportive edifice, through an accessible and cohesive peer support network underpinned by effective training, supervision and remuneration, was considered pivotal to nurture solidarity and potentially resilience. This practical example offers insights into how researchers may facilitate the co-design of acceptable, sustainable interventions

"I don't feel shy because I will be among others who are just like me…": The role of support groups for children perinatally infected with HIV in Zimbabwe.

As access to paediatric antiretroviral therapy (ART) continues to improve in sub-Saharan Africa, a new historically specific cohort of HIV-perinatally infected children surviving into adolescent has emerged. Although remarkable successes have been made clinically in keeping this cohort alive and in reasonable health, their social support experiences are still unknown. The research being reported here sought to explore peer social support experiences of HIV-perinatally infected children in Harare, Zimbabwe. In this article, we draw on 56 repeat in-depth interviews (IDIs) conducted in three phases and two focus group discussions (FGDs) with HIV-infected children (11-13 years). Additional interviews were held with 10 carers. Study findings suggested that both children and carers perceive support groups as a safe social space for learning and acquiring HIV information as well as gaining confidence. Additionally, findings highlighted the importance of consistency of participation. Structural and personal barriers to access and participation in support group were also identified. We conclude that support groups are a useful resource for HIV-infected children and therefore should be supported by stable funding