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DRC Ministry of Health declared the 9th outbreak of Ebola Virus Disease (EVD) in the Equator province on May 8, 2018, that ended on July 25, 2018. There were 54 cases with 38 confirmed, 33 deaths (61%), and 21 survivors in three “zones de santé” (districts). On August 1, 2018, the 10th EVD outbreak of the country was declared in the Ituri and North Kivu provinces. This one is the most important outbreak ever experienced. By November 18, 2018, 373 cases were reported with 326 confirmed and 214 deaths (58%) in two provinces including 14 “zones de santé.” While the 9th outbreak occurred in hard-to-reach areas, the 10th is occurring in fragile security settings, requiring specific strategic/operational approaches.
To describe strategic and operational approaches including IMSs used to address these deadly outbreaks.
A case study methodology using response strategy documents and observations was used, coupled with the use of operation review exercises.
The response strategy evolved continuously taking into account the epidemiological context, including geographical spread. It also took into account cultural, political, and sociological (community resistances) sensitivities. Conditions of pre-existing health system and services were considered. The prevailing security context (armed groups) was taken into account. The evolving situation impacted implementation of response areas including critical interventions like setting up confirmation and treatment centres, rapid response teams, and IMS structures. Areas of response were reviewed continuously, including response structures with further decentralization, outreach, or locally delegated interventions to ensure geographical access and continuity in response services.
Response areas to deal with EVD outbreaks are well known. However, an effective response requires a continuous adjustment of the strategy and a flexible response structures with related IMSs based on regular deep situation analysis. Social sciences still have a critical role to play for that purpose.
It is well known that severe iodine deficiency during pregnancy may cause impaired brain development in the child, with effects on cognitive and motor function, hearing and speech. Whether mild-to-moderate deficiency also affects neurological development is less well known, but in the past decade a number of observational studies have been conducted to answer this question and these studies are reviewed in this article. The picture is now emerging that even mild-to-moderate iodine deficiency during pregnancy may be associated with subtle impairments in cognition and school performance, although the evidence from randomised controlled trials is still lacking. As global efforts to eradicate iodine deficiency in populations continue, it is more likely that mild-to-moderate, rather than severe, iodine deficiency will be the issue of concern in pregnancy, and therefore further research in regions of mild-to-moderate deficiency is required to strengthen the research base and to inform public-health policy.
Post-magmatic alteration of certain magmatic Ni sulfide ores in Western Australia, the Miitel deposit and the Sarah's Find prospect, produced Ni–As–PGE haloes around massive sulfides. A study of the composition of arsenide grains from these hydrothermal haloes, along with arsenides from various magmatic and hydrothermal mineralized environments in other localities, was conducted in order to compare their composition, and assess their potential use as indicator minerals for exploration vectoring, as well as to gain knowledge on their crystallization history. Concentrations in trace elements such as platinum-group elements (PGEs), Au and other metals was obtained by laser ablation inductively coupled plasma mass spectroscopy analyses. Results show that variations in PGEs and Au compositions can be related to the magmatic vs. hydrothermal origin of the grains; and to their provenance from deposits enriched in either Ni, Au or both. Magmatic NiCoFe sulfarsenides have strongly correlated, high IPGE (Os, Ir, Ru, Rh) contents up to 100 ppm Ir, compared with maximum values in hydrothermal sulfarsenides of ~1 ppm. Gold in hydrothermal sulfarsenides from Au-mineralized ultramafic rocks extends up to 500 ppm, with typical values of 3–30 ppm; similar values are also found in nickeline (also called niccolite). These results suggest that nickel arsenides could potentially be used as indicator minerals for nickel and gold exploration. Trace-element contents of arsenide grains in shear zones could be used to deduce the presence of Ni or Au mineralization upstream in the fluid pathway.
To determine the effectiveness of vestibular rehabilitation using the Wii Fit balance platform, in adults with dizziness.
A single-site prospective clinical trial was conducted in a university hospital in the UK. Forty patients with dizziness, who would normally be candidates for vestibular rehabilitation, were identified and considered as potential participants. Participants were randomised into either the treatment group (the Wii Fit group) or the control group (standard customised vestibular rehabilitation protocol). Participants were assessed over a 16-week period using several balance and quality of life questionnaires.
Both exercise regimes resulted in a reduction of dizziness and an improvement in quality of life scores over time, but no statistically significant difference between the two interventions was identified.
This pilot study demonstrated that use of the Wii Fit balance platform resulted in a statistically significant improvement in balance function and quality of life. Furthermore, outcomes were comparable to a similar group of individuals following a standard customised vestibular rehabilitation protocol. The study provides useful information to inform the design and execution of a larger clinical trial.
DNA nanotechnology is a materials design paradigm in which synthetic nucleic acids are used to program the structure and dynamics of nanometer-scale devices and materials. Driven by the convergence of decreasing DNA synthesis costs, advanced yet easy-to-use computational design and analysis tools, and, most importantly, a myriad of innovative studies demonstrating DNA’s extraordinary power to organize functional materials, DNA nanotechnology is spreading into diverse areas of traditional materials science. To further promote the integration of DNA nanotechnology into materials science, this issue of MRS Bulletin provides an overview of the unique capabilities offered by DNA nanotechnology, a set of practical techniques that make it accessible to a broad audience, and a vision for its future applications, described by international leaders in the field.
Iodine deficiency is present in certain groups of the UK population, notably in pregnant women; this is of concern as iodine is required for fetal brain development. UK milk is rich in iodine and is the principal dietary iodine source. UK sales of milk-alternative drinks are increasing but data are lacking on their iodine content. As consumers may replace iodine-rich milk with milk-alternative drinks, we aimed to measure the iodine concentration of those available in the UK. Using inductively coupled plasma-MS, we determined the iodine concentration of seven types of milk-alternative drink (soya, almond, coconut, oat, rice, hazelnut and hemp) by analysing forty-seven products purchased in November/December 2015. For comparison, winter samples of conventional (n 5) and organic (n 5) cows’ milk were included. The median iodine concentration of all of the unfortified milk-alternative drinks (n 44) was low, at 7·3 μg/kg, just 1·7 % of our value for winter conventional cows’ milk (median 438 μg/kg). One brand (not the market leader), fortified its soya, oat and rice drinks with iodine and those drinks had a higher iodine concentration than unfortified drinks, at 280, 287 and 266 μg/kg, respectively. The iodine concentration of organic milk (median 324 μg/kg) was lower than that of conventional milk. Although many milk-alternative drinks are fortified with Ca, at the time of this study, just three of forty-seven drinks were fortified with iodine. Individuals who consume milk-alternative drinks that are not fortified with iodine in place of cows’ milk may be at risk of iodine deficiency unless they consume alternative dietary iodine sources.
Seafood intake in pregnancy has been positively associated with childhood cognitive outcomes which could potentially relate to the high vitamin D content of oily fish. However, whether higher maternal vitamin D status (serum 25-hydroxyvitamin D (25(OH)D)) in pregnancy is associated with a reduced risk of offspring suboptimal neurodevelopmental outcomes is unclear. A total of 7065 mother–child pairs were studied from the Avon Longitudinal Study of Parents and Children cohort who had data for both serum total 25(OH)D concentration in pregnancy and at least one measure of offspring neurodevelopment (pre-school development at 6–42 months; ‘Strengths and Difficulties Questionnaire’ scores at 7 years; intelligence quotient (IQ) at 8 years; reading ability at 9 years). After adjustment for confounders, children of vitamin D-deficient mothers (<50·0 nmol/l) were more likely to have scores in the lowest quartile for gross-motor development at 30 months (OR 1·20; 95 % CI 1·03, 1·40), fine-motor development at 30 months (OR 1·23; 95 % CI 1·05, 1·44) and social development at 42 months (OR 1·20; 95 % CI 1·01, 1·41) than vitamin D-sufficient mothers (≥50·0 nmol/l). No associations were found with neurodevelopmental outcomes, including IQ, measured at older ages. However, our results suggest that deficient maternal vitamin D status in pregnancy may have adverse effects on some measures of motor and social development in children under 4 years. Prevention of vitamin D deficiency may be important for preventing suboptimal development in the first 4 years of life.
Bloat in ruminants is a digestive disorder arising from an abnormal distension of the rumen with gas, and may prove fatal. It is termed chronic when protracted due to physiological disorders and acute when transitory due to feed factors (Cole et al., 1945). Bloat in grazing ruminants is recognised as acute, although the chronic condition at pasture is known (Lyons, 1928). Acute bloat may result from a frothy admixture of gas and ingesta, or from free gas in the rumen (McIntosh, 1941).
The incidence of bloat is world-wide. It is reported most frequently in association with grazing highjy productive pastures and its unpredictability and rapid onset seriously hamper animal and pasture husbandry.
In the same spirit as the local organising committee’s “post-final announcement” I should like, as chairman of this session, to extend an invitation to myself to present a few pre-concluding remarks before asking Brian to summarise his view of the highlights of the past few days. My comments will be eclectic, coloured by a theorist’s wish to impose pattern on chaos; order on the anarchy of observations.
It is now well established, following the classic work of Smak, Warner and Nather, that discs in dwarf novae possess an anisotropic radiation pattern responsible for the hump, or shoulder, that occurs prior to eclipse in the quiescent state, and, in systems with suitable inclination such as TT Gem, responsible also for the primary eclipse itself. In systems with higher inclination such as Z Cha, the primary eclipse is composed of both this anisotropic disc component and the inner-disc/white-dwarf primary component.
Following earlier work of Lynden-Bell & Pringle (1974) and Lightman (1974a, 1974b), Bath & Pringle (1981) have presented a simple method for studying the time-dependent evolution of viscous accretion discs. These models are axisymmetrlc, with the vertical structure reduced to integrated averages of local physical conditions. Published work examines models of dwarf nova eruptions driven by mass transfer bursts (Bath & Pringle 1981 – Paper I), eruptions produced by global viscous changes within the disc (Bath & Pringle 1982a Paper II), and the time-dependent properties of giant discs in symbiotic binaries (Bath & Pringle 1982b – Paper III).
At outburst the classical nova generates an extended optically-thick wind driven by radiation pressure in the continuum. At maximum light the optical luminosity is close to the Eddington-limit. The subsequent decline illustrates the interaction between radiation and matter in a wind which gradually thins as the mass loss rate falls at an approximately constant Eddington-limit luminosity. As the wind thins so the effective photosphere shrinks back into the underlying binary, and an increasing fraction of the radiation is emitted at ultraviolet wavelengths. Model atmosphere computations show how the increasing flux of ultraviolet photons is associated with the shell becoming more and more ionized through radiative ionization. Attempts to study the internal structure of the wind confirm that the luminosity must be close to the Eddington limit and must be expelled from close to the white dwarf surface. It is generally agreed that the outbursts are caused by runaway nuclear burning of accreted material at the white dwarf surface, but it is possible that some events of the classical nova type may be caused by runaway accretion at a super-critical rate.
In dwarf novae very different behaviour is evident. The outbursts are located within the accretion disc and are generated either by mass-transfer bursts due to dynamical instability of the Roche-lobe filling star, or by an instability within the disc itself. In either case the eruption behaviour is due to an enhanced accretion flux through the accretion disc. One important aspect of the radiation hydrodynamics is the luminosity generated by impact of the mass-transfer stream with the accretion disc and penetration by the stream within the disc. Attempts at examining this penetration region are described and results compared with observed behaviour of disc evolution through the course of an outburst. The possibility that disc instabilities will not propogate in realistic discs which deviate from axial symmetry is considered.
We present results for IUE, optical and IR observations of Nova Muscae 1983, from early outburst to January 1986 obtained by the European IUE Target of Opportunity Team. A detailed description of the data will appear elsewhere (Hassall et al., 1989), but here we summarise the most important results.
The outburst lightcurve initially indicated a fast speed class for this nova, but was later characterised by a rather slow optical decline with two or more secondary outbursts with sudden doubling of the bolometric flux. In Figure 1, we show the contributions of X-ray, UV, optical and IR to the total luminosity for 1200 days following outburst, assuming a distance of 4.3kpc and an interstellar extinction E(B-V)=0.5. In the absence of dust formation, first the UV and later the X-ray flux (Ögelman et al, 1984) dominate the radiative energy late into the nebular phase. There was a plateau stage lasting about 500 days, with a bolometric luminosity of ~ 1038ergs s−1 near the Eddington limit. The secondary outbursts were thus super-Eddington. We estimate a total outburst energy (including kinetic and gravitational potential energy of the ejecta) of ~ 5·l046 ergs, corresponding to a mass of ~ 4·10−6Mº of hydrogen burnt in the thermonuclear runaway.
Three aspects of mass transfer instability models of dwarf novae are examined. The hydrodynamic development of instabilities in the secondary are examined within Roche geometry and shown to extend at least a few degrees away from the line of centres. The form of the outburst light curves observed in SS Cygni are shown to be a natural consequence of mass transfer bursts with a duration either less than, or greater than, the disk viscous timescale. Finally the two-dimensional structure of the disc in the plane of the orbit is studied. As with α-disks the viscous evolution time following a burst of mass transfer determines the size of viscosity within the disk. Significant deviations from axial symmetry are found to be present.