Geology, geochemistry and geochronology of the Songwe Hill carbonatite, Malawi

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Songwe Hill, Malawi, is one of the least studied carbonatites but has now become particularly important as it hosts a relatively large rare earth deposit. The results of new mapping, petrography, geochemistry and geochronology indicate that the 0.8 km diameter Songwe Hill is distinct from the other Chilwa Alkaline Province carbonatites in that it intruded the side of the much larger (4 x 6 km) and slightly older (134.6 ± 4.4 Ma) Mauze nepheline syenite and then evolved through three different carbonatite compositions (C1–C3). Early C1 carbonatite is scarce and is composed of medium–coarse-grained calcite carbonatite containing zircons with a U–Pb age of 132.9 ± 6.7 Ma. It is similar to magmatic carbonatite in other carbonatite complexes at Chilwa Island and Tundulu in the Chilwa Alkaline Province and others worldwide. The fine-grained calcite carbonatite (C2) is the most abundant stage at Songwe Hill, followed by a more REE- and Sr-rich ferroan calcite carbonatite (C3). Both stages C2 and C3 display evidence of extensive (carbo)-hydrothermal overprinting that has produced apatite enriched in HREE (<2000 ppm Y) and, in C3, synchysite-(Ce). The final stages comprise HREE-rich apatite fluorite veins and Mn-Fe-rich veins. Widespread brecciation and incorporation of fenite into carbonatite, brittle fracturing, rounded clasts and a fenite carapace at the top of the hill indicate a shallow level of emplacement into the crust. This shallow intrusion level acted as a reservoir for multiple stages of carbonatite-derived fluid and HREE-enriched apatite mineralisation as well as LREE-enriched synchysite-(Ce). The close proximity and similar age of the large Mauze nepheline syenite suggests it may have acted as a heat source driving a hydrothermal system that has differentiated Songwe Hill from other Chilwa carbonatites.Thanks are due to A. Lemon, A. Zabula, C. Mcheka, I. Nkukumila (Mkango Resources Ltd.), É. Deady (BGS) and P. Armitage (Paul Armitage Consulting Ltd.) for logistical support and enthusiastic discussions in the field. This contribution benefitted from reviews by Jindřich Kynický and Ray Macdonald, as well as anonymous reviewers, who we thank for their time and insightful comments. This work was funded by a NERC BGS studentship to SBF (NEE/J50318/1; S208), the NERC SoS RARE consortium (NE/M011429/1) and by Mkango Resources Ltd. AGG publishes with the permission of the Executive Director of the British Geological Survey (NERC)

The global distribution and burden of dengue.

Dengue is a systemic viral infection transmitted between humans by Aedes mosquitoes. For some patients, dengue is a life-threatening illness. There are currently no licensed vaccines or specific therapeutics, and substantial vector control efforts have not stopped its rapid emergence and global spread. The contemporary worldwide distribution of the risk of dengue virus infection and its public health burden are poorly known. Here we undertake an exhaustive assembly of known records of dengue occurrence worldwide, and use a formal modelling framework to map the global distribution of dengue risk. We then pair the resulting risk map with detailed longitudinal information from dengue cohort studies and population surfaces to infer the public health burden of dengue in 2010. We predict dengue to be ubiquitous throughout the tropics, with local spatial variations in risk influenced strongly by rainfall, temperature and the degree of urbanization. Using cartographic approaches, we estimate there to be 390 million (95% credible interval 284-528) dengue infections per year, of which 96 million (67-136) manifest apparently (any level of disease severity). This infection total is more than three times the dengue burden estimate of the World Health Organization. Stratification of our estimates by country allows comparison with national dengue reporting, after taking into account the probability of an apparent infection being formally reported. The most notable differences are discussed. These new risk maps and infection estimates provide novel insights into the global, regional and national public health burden imposed by dengue. We anticipate that they will provide a starting point for a wider discussion about the global impact of this disease and will help to guide improvements in disease control strategies using vaccine, drug and vector control methods, and in their economic evaluation

Prostatic sarcoma after treatment of rectal cancer

<p>Abstract</p> <p>Background</p> <p>The relationship between radiation exposure for treatment of cancer and occurrence of a second primary cancer at the irradiated site is well known. This phenomenon is however rare in prostate.</p> <p>Case presentation</p> <p>A 75-year-old farmer was treated for rectal cancer with preoperative 45 Gy of radiotherapy and abdominoperineal resection. Four years later he developed symptoms of bladder outlet obstruction and acute urinary retention. He underwent a transurethral resection of the prostate. Histological examination of the removed prostate tissue and immunohistochemistry revealed it to be a poorly differentiated sarcoma.</p> <p>Conclusion</p> <p>We believe this to be the first reported case of radiation-induced sarcoma following radiotherapy treatment for rectal cancer. Since radiotherapy plays a pivotal role in the contemporary treatment of rectal adenocarcinoma, it is relevant to be aware of the potential long-term carcinogenic complications of radiotherapy of the pelvis.</p

Predictors of longitudinal change in bone mineral density in a cohort of HIV-positive and negative subjects.

OBJECTIVE: Although low bone mineral density (BMD) is prevalent in HIV, changes in BMD over time remain unclear. We aimed to compare rates of, and factors associated with, BMD change between HIV-positive and HIV-negative subjects. METHODS: In a prospective, 3-year cohort, HIV-positive and HIV-negative subjects provided annual demographic and clinical data, fasting bloods and dual x-ray absorptiometry (DXA). Using longitudinal mixed models we compared and determined predictors of rate of change in BMD. RESULTS: Of 384 subjects (45.8% HIV-positive), 120 contributed two and 264 contributed three BMD measurements. Those with HIV were younger (median (IQR) 39 (34-46) vs 43 (35-50) years; p=0.04), more often male (61% vs 46%; p = 0.003) and less likely Caucasian (61% vs 82%; p 30 years, Caucasian ethnicity, and not being on ART during follow-up were associated with greater decline and higher parathyroid hormone associated with a smaller decline in BMD at the femoral neck. We found no association between BMD change and exposure to tenofovir disoproxil fumarate or protease inhibitors. CONCLUSIONS: We observed no difference in rate of BMD decline regardless of HIV status and in HIV positive subject, having started ART within the previous three months was the only factor associated with greater BMD decline at all 3 sites

Football fans in training: the development and optimization of an intervention delivered through professional sports clubs to help men lose weight, become more active and adopt healthier eating habits

&lt;p&gt;Background: The prevalence of obesity in men is rising, but they are less likely than women to engage in existing weight management programmes. The potential of professional sports club settings to engage men in health promotion activities is being increasingly recognised. This paper describes the development and optimization of the Football Fans in Training (FFIT) programme, which aims to help overweight men (many of them football supporters) lose weight through becoming more active and adopting healthier eating habits.&lt;/p&gt; &lt;p&gt;Methods: The MRC Framework for the design and evaluation of complex interventions was used to guide programme development in two phases. In Phase 1, a multidisciplinary working group developed the pilot programme (p-FFIT) and used a scoping review to summarize previous research and identify the target population. Phase 2 involved a process evaluation of p-FFIT in 11 Scottish Premier League (SPL) clubs. Participant and coach feedback, focus group discussions and interviews explored the utility/acceptability of programme components and suggestions for changes. Programme session observations identified examples of good practice and problems/issues with delivery. Together, these findings informed redevelopment of the optimized programme (FFIT), whose components were mapped onto specific behaviour change techniques using an evidence-based taxonomy.&lt;/p&gt; &lt;p&gt;Results: p-FFIT comprised 12, weekly, gender-sensitised, group-based weight management classroom and ‘pitch-side’ physical activity sessions. These in-stadia sessions were complemented by an incremental, pedometer-based walking programme. p-FFIT was targeted at men aged 35-65 years with body mass index ≥ 27 kg/m2. Phase 2 demonstrated that participants in p-FFIT were enthusiastic about both the classroom and physical activity components, and valued the camaraderie and peer-support offered by the programme. Coaches appreciated the simplicity of the key healthy eating and physical activity messages. Suggestions for improvements that were incorporated into the optimized FFIT programme included: more varied in-stadia physical activity with football-related components; post-programme weight management support (emails and a reunion session); and additional training for coaches in SMART goal setting and the pedometer-based walking programme.&lt;/p&gt; &lt;p&gt;Conclusions: The Football Fans in Training programme is highly acceptable to participants and SPL coaches, and is appropriate for evaluation in a randomised controlled trial.&lt;/p&gt

A First- and Second-Order Motion Energy Analysis of Peripheral Motion Illusions Leads to Further Evidence of “Feature Blur” in Peripheral Vision

Anatomical and physiological differences between the central and peripheral visual systems are well documented. Recent findings have suggested that vision in the periphery is not just a scaled version of foveal vision, but rather is relatively poor at representing spatial and temporal phase and other visual features. Shapiro, Lu, Huang, Knight, and Ennis (2010) have recently examined a motion stimulus (the “curveball illusion”) in which the shift from foveal to peripheral viewing results in a dramatic spatial/temporal discontinuity. Here, we apply a similar analysis to a range of other spatial/temporal configurations that create perceptual conflict between foveal and peripheral vision.To elucidate how the differences between foveal and peripheral vision affect super-threshold vision, we created a series of complex visual displays that contain opposing sources of motion information. The displays (referred to as the peripheral escalator illusion, peripheral acceleration and deceleration illusions, rotating reversals illusion, and disappearing squares illusion) create dramatically different perceptions when viewed foveally versus peripherally. We compute the first-order and second-order directional motion energy available in the displays using a three-dimensional Fourier analysis in the (x, y, t) space. The peripheral escalator, acceleration and deceleration illusions and rotating reversals illusion all show a similar trend: in the fovea, the first-order motion energy and second-order motion energy can be perceptually separated from each other; in the periphery, the perception seems to correspond to a combination of the multiple sources of motion information. The disappearing squares illusion shows that the ability to assemble the features of Kanisza squares becomes slower in the periphery.The results lead us to hypothesize “feature blur” in the periphery (i.e., the peripheral visual system combines features that the foveal visual system can separate). Feature blur is of general importance because humans are frequently bringing the information in the periphery to the fovea and vice versa

Insidious procedures: diversity awards legitimize unfair organizational practices

This is the author's version of an article subsequently published in Social Justice Research in final format. The final publication is available at Springer via http://dx.doi.org/10.1007/s11211-015-0240-zDoes the presence (versus absence) of an organizational diversity award increase the perceived fairness of biased personnel procedures? Participants examined fair or unfair personnel procedures at a company that had received a diversity award or an award unrelated to diversity. When the company had received a diversity award (versus a control award), participants perceived the unfair personnel procedure as fairer for minorities, and White participants were more supportive of enacting the biased procedure. These findings suggest that organizations perceived as successfully supporting diversity might be afforded particular legitimacy to enact policies and procedures that disadvantage the very groups they are perceived as valuing.National Science Foundatio

Cleanup of industrial effluents containing heavy metals : a new opportunity of valorising the biomass produced by brewing industry

Heavy metal pollution is a matter of concern in industrialised countries. Contrary to organic pollutants, heavy metals are not metabolically degraded. This fact has two main consequences: its bioremediation requires another strategy and heavy metals can be indefinitely recycled. Yeast cells of Saccharomyces cerevisiae are produced at high amounts as a by-product of brewing industry constituting a cheap raw material. In the present work, the possibility of valorising this type of biomass in the bioremediation of real industrial effluents containing heavy metals is reviewed. Given the auto-aggregation capacity (flocculation) of brewing yeast cells, a fast and off-cost yeast separation is achieved after the treatment of metal-laden effluent, which reduces the costs associated with the process. This is a critical issue when we are looking for an effective, eco-friendly, and low-cost technology. The possibility of the bioremediation of industrial effluents linked with the selective recovery of metals, in a strategy of simultaneous minimisation of environmental hazard of industrial wastes with financial benefits from reselling or recycling the metals, is discussed