Is the Earth Crying Wolf? Exploring Knowledge Source and Certainty in High School Students\u27 Analysis of Global Warming News

The marked contrast between the scientific consensus on global warming and public beliefs indicates a need to research how high schoolers, as future citizens, engage with and make meaning from news articles on such topics. In the case of socioscientific issues (SSIs) such as global warming, students’ acquisition of knowledge from the news is mediated by their epistemic understandings of the nature of science (NOS) and use of informal reasoning in evaluating claims, evidence, and sources. This exploratory qualitative study examined twelve U.S. high school students’ understandings, opinions, and epistemic beliefs concerning global warming knowledge. Researchers examined microgenetic changes as students discussed global warming during semi-structured interviews and a close reading of global warming news texts. Although results showed that most students could articulate a working concept of global warming, in follow-up questions, a subset offered personal opinions that differed from or contradicted their previously stated understandings. Meanwhile, students who offered opinions consistent with the scientific consensus often argued that the dangers of global warming were exaggerated by politicians and scientists who wished to profit from the issue. This study suggests a need for more explicit focus on NOS and scientific news literacy in curricula, as well as further research into the interplay between epistemic beliefs and the informal reasoning students use to negotiate diverse sources of SSI knowledge—from the classroom to the news media and public life

Two-Loop Sudakov Form Factor in a Theory with Mass Gap

The two-loop Sudakov form factor is computed in a U(1) model with a massive gauge boson and a $U(1)\times U(1)$ model with mass gap. We analyze the result in the context of hard and infrared evolution equations and establish a matching procedure which relates the theories with and without mass gap setting the stage for the complete calculation of the dominant two-loop corrections to electroweak processes at high energy.Comment: Latex, 5 pages, 2 figures. Bernd Feucht is Bernd Jantzen in later publications. (The contents of the paper is unchanged.

The impact of health programmes to prevent vertical transmission of HIV. Advances, emerging health challenges and research priorities for children exposed to or living with HIV: Perspectives from South Africa

Over the past three decades, tremendous global progress in preventing and treating paediatric HIV infection has been achieved. This paper highlights the emerging health challenges of HIV-exposed uninfected (HEU) children and the ageing population of children living with HIV (CLHIV), summarises programmatic opportunities for care, and highlights currently conducted research and remaining research priorities in high HIV-prevalence settings such as South Africa. Emerging health challenges amongst HEU children and CLHIV include preterm delivery, suboptimal growth, neurodevelopmental delay, mental health challenges, infectious disease morbidity and mortality, and acute and chronic respiratory illnesses including tuberculosis, pneumonia, bronchiectasis and lymphocytic interstitial pneumonitis. CLHIV and HEU children require three different categories of care: (i) optimal routine child health services applicable to all children; (ii) routine care currently provided to all HEU children and CLHIV, such as HIV testing or viral load monitoring, respectively, and (iii) additional care for CLHIV and HEU children who may have growth, neurodevelopmental, behavioural, cognitive or other deficits such as chronic lung disease, and require varying degrees of specialised care. However, the translation thereof into practice has been hampered by various systemic challenges, including shortages of trained healthcare staff, suboptimal use of the patient-held child’s Road to Health book for screening and referral purposes, inadequate numbers and distribution of therapeutic staff, and shortages of assistive/diagnostic devices, where required. Additionally, in low-middle-income high HIV-prevalence settings, there is a lack of evidence-based solutions/models of care to optimise health amongst HEU and CLHIV. Current research priorities include understanding the mechanisms of preterm birth in women living with HIV to optimise preventive interventions; establishing pregnancy pharmacovigilance systems to understand the short-, medium- and long-term impact of in utero ART and HIV exposure; understanding the role of preconception maternal ART on HEU child infectious morbidity and long-term growth and neurodevelopmental trajectories in HEU children and CLHIV, understanding mental health outcomes and support required in HEU children and CLHIV through childhood and adolescence; monitoring HEU child morbidity and mortality compared with HIV-unexposed children; monitoring outcomes of CLHIV who initiated ART very early in life, sometimes with suboptimal ART regimens owing to medication formulation and registration issues; and testing sustainable models of care for HEU children and CLHIV including later reproductive care and support

Hypoxia induces dilated cardiomyopathy in the chick embryo: mechanism, intervention, and long-term consequences

Background: Intrauterine growth restriction is associated with an increased future risk for developing cardiovascular diseases. Hypoxia in utero is a common clinical cause of fetal growth restriction. We have previously shown that chronic hypoxia alters cardiovascular development in chick embryos. The aim of this study was to further characterize cardiac disease in hypoxic chick embryos. Methods: Chick embryos were exposed to hypoxia and cardiac structure was examined by histological methods one day prior to hatching (E20) and at adulthood. Cardiac function was assessed in vivo by echocardiography and ex vivo by contractility measurements in isolated heart muscle bundles and isolated cardiomyocytes. Chick embryos were exposed to vascular endothelial growth factor (VEGF) and its scavenger soluble VEGF receptor-1 (sFlt-1) to investigate the potential role of this hypoxia-regulated cytokine. Principal Findings: Growth restricted hypoxic chick embryos showed cardiomyopathy as evidenced by left ventricular (LV) dilatation, reduced ventricular wall mass and increased apoptosis. Hypoxic hearts displayed pump dysfunction with decreased LV ejection fractions, accompanied by signs of diastolic dysfunction. Cardiomyopathy caused by hypoxia persisted into adulthood. Hypoxic embryonic hearts showed increases in VEGF expression. Systemic administration of rhVEGF165 to normoxic chick embryos resulted in LV dilatation and a dose-dependent loss of LV wall mass. Lowering VEGF levels in hypoxic embryonic chick hearts by systemic administration of sFlt-1 yielded an almost complete normalization of the phenotype. Conclusions/Significance: Our data show that hypoxia causes a decreased cardiac performance and cardiomyopathy in chick embryos, involving a significant VEGF-mediated component. This cardiomyopathy persists into adulthood

Closing the gaps to eliminate mother-to-child transmission of HIV (MTCT) in South Africa: Understanding MTCT case rates, factors that hinder the monitoring and attainment of targets, and potential game changers

Background. Ninety percent of the world’s HIV-positive pregnant women live in 22 countries. These 22 countries, including South Africa (SA) have prioritised the elimination of mother-to-child transmission of HIV (EMTCT). Since 2016 all 22 countries recommend lifelong antiretroviral treatment for all HIV-positive pregnant and lactating women. To measure South African national, provincial and district-level progress towards attaining EMTCT, we analysed the number of in utero (IU) paedatric HIV infections per 100 000 live births (IU case rate), and synthesised factors hindering the monitoring of EMTCT progress and attainment from the viewpoint of provincial and district-level healthcare managers and implementers. We highlight potential innovations to strengthen health systems and improve EMTCT programme delivery. Methods. We reviewed national-, provincial- and district-level birth HIV testing data from routine National Health Laboratory Services (NHLS) records between April 2016 and March 2017. To obtain a qualitative perspective from healthcare managers and implementers, we synthesised information from the nine 2016 provincial-level EMTCT stock-taking workshops. These workshops involve key provincial and district-level staff, mentors and supporting partners. Lastly, we highlight potential innovations presented at these workshops to overcome operational challenges. Results. The national IU mother-to-child transmission (MTCT) rate was 0.9%, which translated to an IU case rate of 245 HIV-positive neonates per 100 000 live births. Provincial IU percent MTCT risk ranged from 0.6% to 1.3%, with IU case rates ranging between 168 and 325 cases per 100 000 live births. District-level IU percent MTCT risk ranged from 0.4% to 1.9%. Potential game changers include: pre-conception counselling to optimise maternal-partner health, weekly dissemination of HIV polymerase chain reaction (PCR) and viral load reports from the NHLS to specific individuals who trace mothers and infants needing care, use of ward-based outreach teams and community caregivers to trace HIV-infected mothers and their infants to link them into care, inclusion of a unique identifier in patient-held infant Road to Health booklets to facilitate infant tracing and continuous quality improvement (CQI) processes within facilities and districts and implementation of an HIV-positive baby tool to understand the characteristics and risks of HIV-positive infants. On an ecological level, provinces and districts using community-based approaches and CQI methodology seemed to have lower MTCT and IU case rates. Conclusions. More quantitative analyses are needed to understand what proportion of the success can be attributed to community-based and CQI approaches and the impact of the potential game changers on progress towards EMTCT

Parental access to hospitalised children during infectious disease pandemics such as COVID-19

The COVID-19 pandemic has resulted in many hospitals severely limiting or denying parents access to their hospitalised children. This article provides guidance for hospital managers, healthcare staff, district-level managers and provincial managers on parental access to hospitalised children during a pandemic such as COVID-19. It: (i) summarises legal and ethical issues around parental visitation rights; (ii) highlights four guiding principles; (iii) provides 10 practical recommendations to facilitate safe parental access to hospitalised children; (iv) highlights additional considerations if the mother is COVID-19-positive; and (v) provides considerations for fathers. In summary, it is a child’s right to have access to his or her parents during hospitalisation, and parents should have access to their hospitalised children; during an infectious disease pandemic such as COVID-19, there is a responsibility to ensure that parental visitation is implemented in a reasonable and safe manner. Separation should only occur in exceptional circumstances, e.g. if adequate in-hospital facilities do not exist to jointly accommodate the parent/caregiver and the newborn/infant/child. Both parents should be allowed access to hospitalised children, under strict infection prevention and control (IPC) measures and with implementation of non-pharmaceutical interventions (NPIs), including handwashing/sanitisation, face masks and physical distancing. Newborns/infants and their parents/caregivers have a reasonably high likelihood of having similar COVID-19 status, and should be managed as a dyad rather than as individuals. Every hospital should provide lodger/boarder facilities for mothers who are COVID-19-positive, COVID-19-negative or persons under investigation (PUI), separately, with stringent IPC measures and NPIs. If facilities are limited, breastfeeding mothers should be prioritised, in the following order: (i) COVID-19-negative; (ii) COVID-19 PUI; and (iii) COVID-19-positive. Breastfeeding, or breastmilk feeding, should be promoted, supported and protected, and skin-to-skin care of newborns with the mother/caregiver (with IPC measures) should be discussed and practised as far as possible. Surgical masks should be provided to all parents/caregivers and replaced daily throughout the hospital stay. Parents should be referred to social services and local community resources to ensure that multidisciplinary support is provided. Hospitals should develop individual-level policies and share these with staff and parents. Additionally, hospitals should ideally track the effect of parental visitation rights on hospital-based COVID-19 outbreaks, the mental health of hospitalised children, and their rate of recovery.South African Medical Research Councilhttp://www.samj.org.zaPaediatrics and Child Healt

The impact of health programmes to prevent vertical transmission of HIV. Advances, emerging health challenges and research priorities for children exposed to or living with HIV : perspectives from South Africa

CITATION: Goga, A., et al. 2019. The impact of health programmes to prevent vertical transmission of HIV. Advances, emerging health challenges and research priorities for children exposed to or living with HIV : perspectives from South Africa. South African Medical Journal, 109(11b):77-82, doi:10.7196/SAMJ.2019.v109i11b.14292.The original publication is available at http://www.samj.org.zaENGLISH ABSTRACT: Over the past three decades, tremendous global progress in preventing and treating paediatric HIV infection has been achieved. This paper highlights the emerging health challenges of HIV-exposed uninfected (HEU) children and the ageing population of children living with HIV (CLHIV), summarises programmatic opportunities for care, and highlights currently conducted research and remaining research priorities in high HIV-prevalence settings such as South Africa. Emerging health challenges amongst HEU children and CLHIV include preterm delivery, suboptimal growth, neurodevelopmental delay, mental health challenges, infectious disease morbidity and mortality, and acute and chronic respiratory illnesses including tuberculosis, pneumonia, bronchiectasis and lymphocytic interstitial pneumonitis. CLHIV and HEU children require three different categories of care: (i) optimal routine child health services applicable to all children; (ii) routine care currently provided to all HEU children and CLHIV, such as HIV testing or viral load monitoring, respectively, and (iii) additional care for CLHIV and HEU children who may have growth, neurodevelopmental, behavioural, cognitive or other deficits such as chronic lung disease, and require varying degrees of specialised care. However, the translation thereof into practice has been hampered by various systemic challenges, including shortages of trained healthcare staff, suboptimal use of the patient-held child’s Road to Health book for screening and referral purposes, inadequate numbers and distribution of therapeutic staff, and shortages of assistive/diagnostic devices, where required. Additionally, in low-middle-income high HIV-prevalence settings, there is a lack of evidence-based solutions/models of care to optimise health amongst HEU and CLHIV. Current research priorities include understanding the mechanisms of preterm birth in women living with HIV to optimise preventive interventions; establishing pregnancy pharmacovigilance systems to understand the short-, medium- and long-term impact of in utero ART and HIV exposure; understanding the role of preconception maternal ART on HEU child infectious morbidity and long-term growth and neurodevelopmental trajectories in HEU children and CLHIV, understanding mental health outcomes and support required in HEU children and CLHIV through childhood and adolescence; monitoring HEU child morbidity and mortality compared with HIV-unexposed children; monitoring outcomes of CLHIV who initiated ART very early in life, sometimes with suboptimal ART regimens owing to medication formulation and registration issues; and testing sustainable models of care for HEU children and CLHIV including later reproductive care and support.http://www.samj.org.za/index.php/samj/article/view/12806Publisher's versio

Tumor Angiogenesis and Vascular Patterning: A Mathematical Model

Understanding tumor induced angiogenesis is a challenging problem with important consequences for diagnosis and treatment of cancer. Recently, strong evidences suggest the dual role of endothelial cells on the migrating tips and on the proliferating body of blood vessels, in consonance with further events behind lumen formation and vascular patterning. In this paper we present a multi-scale phase-field model that combines the benefits of continuum physics description and the capability of tracking individual cells. The model allows us to discuss the role of the endothelial cells' chemotactic response and proliferation rate as key factors that tailor the neovascular network. Importantly, we also test the predictions of our theoretical model against relevant experimental approaches in mice that displayed distinctive vascular patterns. The model reproduces the in vivo patterns of newly formed vascular networks, providing quantitative and qualitative results for branch density and vessel diameter on the order of the ones measured experimentally in mouse retinas. Our results highlight the ability of mathematical models to suggest relevant hypotheses with respect to the role of different parameters in this process, hence underlining the necessary collaboration between mathematical modeling, in vivo imaging and molecular biology techniques to improve current diagnostic and therapeutic tools