A source of extended HCO+ emission in young stellar objects

Anomalous molecular line profile shapes are the strongest indicators of the presence of the infall of gas that is associated with star formation. Such profiles are seen for well-known tracers, such as HCO+, CS and H2CO. In certain cases, optically thick emission lines with appropriate excitation criteria may possess the asymmetric double-peaked profiles that are characteristic of infall. However, recent interpretations of the HCO+ infall profile observed towards the protostellar infall candidate B335 have revealed a significant discrepancy between the inferred overall column density of the molecule and that which is predicted by standard dark cloud chemical modelling. This paper presents a model for the source of the HCO+ emission excess. Observations have shown that, in low-mass star-forming regions, the collapse process is invariably accompanied by the presence of collimated outflows; we therefore propose the presence of an interface region around the outflow in which the chemistry is enriched by the action of jets. This hypothesis suggests that the line profiles of HCO+, as well as other molecular species, may require a more complex interpretation than can be provided by simple, chemically quiescent, spherically symmetric infall models. The enhancement of HCO+ depends primarily on the presence of a shock-generated radiation field in the interface. Plausible estimates of the radiation intensity imply molecular abundances that are consistent with those observed. Further, high-resolution observations of an infall-outflow source show HCO+ emission morphology that is consistent with that predicted by this model

Modelling of partially-resolved oceanic symmetric instability

A series of idealized numerical models have been developed to investigate the effects of partially resolved symmetric instability (SI) in oceanic general circulation models. An analysis of the energetics of symmetric instability is used to argue that the mixed layer can be at least partially restratified even when some SI modes are absent due to either large horizontal viscosity or coarse model resolution. Linear stability analysis reveals that in the idealized models the amount of restratification can be predicted as a function of the grid spacing and viscosity. The models themselves are used to demonstrate these predictions and reveal three possible outcomes in steady-state: (1) incomplete restratification due to viscosity, (2) incomplete restratification due to resolution, and (3) excessive restratification due to anisotropy of the viscosity. The third outcome occurs even on a high-resolution isotropic grid and in two separate numerical models, and thus appears to be a sort of robust numerical feature. The three outcomes are used to recommend criteria that a successful SI parameterization should satisfy.The authors gratefully acknowledge support from the Natural Environment Research Council, award NE/J010472/1.This is the final published version. It originally was originally published by Elsevier at http://www.sciencedirect.com/science/article/pii/S1463500314000961

Before Sustainable Development Goals (SDG): why Nigeria failed to achieve the Millennium Development Goals (MDGs).

World leaders adopted the UN Millennium Declaration in 2000, which committed the nations of the world to a new global partnership, aimed at reducing extreme poverty and other time-bound targets, with a stated deadline of 2015. Fifteen years later, although significant progress has been made worldwide, Nigeria is lagging behind for a variety of reasons, including bureaucracy, poor resource management in the healthcare system, sequential healthcare worker industrial action, Boko Haram insurgency in the north of Nigeria and kidnappings in the south of Nigeria. The country needs to tackle these problems to be able to significantly advance with the new sustainable development goals (SDGs) by the 2030 target date

Before Sustainable Development Goals (SDG): why Nigeria failed to achieve the Millennium Development Goals (MDGs).

World leaders adopted the UN Millennium Declaration in 2000, which committed the nations of the world to a new global partnership, aimed at reducing extreme poverty and other time-bound targets, with a stated deadline of 2015. Fifteen years later, although significant progress has been made worldwide, Nigeria is lagging behind for a variety of reasons, including bureaucracy, poor resource management in the healthcare system, sequential healthcare worker industrial action, Boko Haram insurgency in the north of Nigeria and kidnappings in the south of Nigeria. The country needs to tackle these problems to be able to significantly advance with the new sustainable development goals (SDGs) by the 2030 target date

Ebola virus disease epidemic in West Africa: Lessons learned and issues arising from West African countries

© Royal College of Physicians 2015. All rights reserved.The current Ebola virus disease (EVD) outbreak ravaging three nations in West Africa has affected more than 14,000 persons and killed over 5,000. It is the longest and most widely spread Ebola epidemic ever seen. At the time of this overview (written November 2014), having affected eight different nations, Nigeria and Senegal were able to control and eliminate the virus within a record time. Ghana has successfully, to date, kept the virus away from the country, despite economic and social relationships with affected nations. What lessons can we learn from Nigeria, Senegal and Ghana in the current epidemic? How can the world improve the health systems in low- and middle-income countries to effectively manage future outbreaks? Recently, the Royal College of Physicians launched a new partnership with the West African College of Physicians to curtail the effects of HIV/AIDS, malaria and tuberculosis in the region. We believe that strengthened health systems, skilled human resources for health and national ownership of problems are key to effective management of outbreaks such as EVD

Hepatic steatosis and fibrosis: Non-invasive assessment

Chronic liver disease is a major cause of morbidity and mortality worldwide and usually develops over many years, as a result of chronic inflammation and scarring, resulting in end-stage liver disease and its complications. The progression of disease is characterised by ongoing inflammation and consequent fibrosis, although hepatic steatosis is increasingly being recognised as an important pathological feature of disease, rather than being simply an innocent bystander. However, the current gold standard method of quantifying and staging liver disease, histological analysis by liver biopsy, has several limitations and can have associated morbidity and even mortality. Therefore, there is a clear need for safe and noninvasive assessment modalities to determine hepatic steatosis, inflammation and fibrosis. This review covers key mechanisms and the importance of fibrosis and steatosis in the progression of liver disease. We address non-invasive imaging and blood biomarker assessments that can be used as an alternative to information gained on liver biopsy

Sustainable Health Development Goals (SHDG): breaking down the walls.

The worlds governments failed to achieve the Health for All 2000 goals from the Alma Ata Declaration of 1978. Although a lot of milestones have been covered since 2000, the worlds governing authorities are unlikely to achieve the current Millennium Development Goals (MDGs) which expire by the end of this year. The inability to achieve these goals may be linked to the multiplicity of health-related directives and fragmentation of health systems in many countries. However, with the proposed 17 sustainability development goals, health has only one universal aim: to ensure healthy lives and promote wellbeing for all at all ages. Accomplishing this will require a focus on health systems (system-thinking), commonization of services and full integration of services with total dismantling of vertical programs across the world

Is the prevalence of HIV wrongly estimated in Nigeria? Some insights from a 2017 World AIDS day experience from a Nigerian Non-Governmental Organisation

Introduction: HIV is still a major public health challenge, especially in resource-limited settings. In Nigeria, it is estimated that over 50% of those infected with HIV do not know their status. With the recent Nigerian governmental approval of a "Test and Start Strategy", we embarked on HIV testing and services in four defined locations to mark 2017 World AIDS Day. The aim of this report is to document the process and outcome of the exercise. Methods: four teams led by senior clinical associates implemented the services and were mandated to test at least 100 persons per location. At each location, we carried out the following activities: (1) short advocacy to community leaders, (2) HIV testing and counselling, (3) disclosure of results, post-test counselling and healthy life-style education and (4) distribution of free male condoms and Information, Education and Communication (IEC) material. Results: a total of 237 people (male 195, female 42) were tested, the majority of whom were between 19 and 49 years (93.7%). Two people were found to be positive, giving a 0.84% positivity rate. Informal interactions between service providers and the people tested revealed that people were aware of HIV as a public health problem, and people positively received HIV services. Although there is a selection bias, as those tested will not be truly representative of the population, the current positively rate of less than 1% is low compared to previous Nigerian estimates, which are based on antenatal testing. However, the exercise showed a willingness to be tested and fair knowledge of HIV as a problem. Population-based data from across Nigeria should be aggregated to determine community prevalence pending the National population-based HIV survey in 2018. Such information will inform evidence-based decisions on the necessity of such large-scale surveys in future years. Conclusion: there is an urgent need to define the real prevalence of HIV in Nigeria through a well planned and executed community based survey

Meta-analysis: the diagnostic accuracy of critical flicker frequency in minimal hepatic encephalopathy

BACKGROUND: Minimal hepatic encephalopathy (MHE) reduces quality of life, increases the risk of road traffic incidents and predicts progression to overt hepatic encephalopathy and death. Current psychometry-based diagnostic methods are effective, but time-consuming and a universal ‘gold standard’ test has yet to be agreed upon. Critical Flicker Frequency (CFF) is a proposed language-independent diagnostic tool for MHE, but its accuracy has yet to be confirmed. AIM: To assess the diagnostic accuracy of CFF for MHE by performing a systematic review and meta-analysis of all studies, which report on the diagnostic accuracy of this test. METHODS: A systematic literature search was performed to locate all publications reporting on the diagnostic accuracy of CFF for MHE. Data were extracted from 2 × 2 tables or calculated from reported accuracy data. Collated data were meta-analysed for sensitivity, specificity, diagnostic odds ratio (DOR) and summary receiver operator curve (sROC) analysis. Prespecified subgroup analysis and meta-regression were also performed. RESULTS: Nine studies with data for 622 patients were included. Summary sensitivity was 61% (95% CI: 55–67), specificity 79% (95% CI: 75–83) and DOR 10.9 (95% CI: 4.2–28.3). A symmetrical sROC gave an area under the receiver operator curve of 0.84 (SE = 0.06). The heterogeneity of the DOR was 74%. CONCLUSIONS: Critical Flicker Frequency has a high specificity and moderate sensitivity for diagnosing minimal hepatic encephalopathy. Given the advantages of language independence and being both simple to perform and interpret, we suggest the use of critical flicker frequency as an adjunct (but not replacement) to psychometric testing