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Space Infrared Telescope for Cosmology and Astrophysics (SPICA), the cryogenic infrared space telescope recently pre-selected for a ‘Phase A’ concept study as one of the three remaining candidates for European Space Agency (ESA's) fifth medium class (M5) mission, is foreseen to include a far-infrared polarimetric imager [SPICA-POL, now called B-fields with BOlometers and Polarizers (B-BOP)], which would offer a unique opportunity to resolve major issues in our understanding of the nearby, cold magnetised Universe. This paper presents an overview of the main science drivers for B-BOP, including high dynamic range polarimetric imaging of the cold interstellar medium (ISM) in both our Milky Way and nearby galaxies. Thanks to a cooled telescope, B-BOP will deliver wide-field 100–350
m images of linearly polarised dust emission in Stokes Q and U with a resolution, signal-to-noise ratio, and both intensity and spatial dynamic ranges comparable to those achieved by Herschel images of the cold ISM in total intensity (Stokes I). The B-BOP 200
m images will also have a factor
30 higher resolution than Planck polarisation data. This will make B-BOP a unique tool for characterising the statistical properties of the magnetised ISM and probing the role of magnetic fields in the formation and evolution of the interstellar web of dusty molecular filaments giving birth to most stars in our Galaxy. B-BOP will also be a powerful instrument for studying the magnetism of nearby galaxies and testing Galactic dynamo models, constraining the physics of dust grain alignment, informing the problem of the interaction of cosmic rays with molecular clouds, tracing magnetic fields in the inner layers of protoplanetary disks, and monitoring accretion bursts in embedded protostars.
The National Institute for Health and Care Excellence referral guidelines prompting urgent two-week referrals were updated in 2015. Additional symptoms with a lower threshold of 3 per cent positive predictive values were integrated. This study aimed to examine whether current pan-London urgent referral guidelines for suspected head and neck cancer lead to efficient and accurate referrals by assessing frequency of presenting symptoms and risk factors, and examining their correlation with positive cancer diagnoses.
The risk factors and symptoms of 984 consecutive patients (over a six-month period in 2016) were collected retrospectively from urgent referral letters to University College London Hospital for suspected head and neck cancer.
Only 37 referrals (3.76 per cent) resulted in a head and neck cancer diagnosis. Four of the 23 recommended symptoms demonstrated statistically significant results. Nine of the 23 symptoms had a positive predictive value of over 3 per cent.
The findings indicate that the current referral guidelines are not effective at detecting patients with cancer. Detection rates have decreased from 10–15 per cent to 3.76 per cent. A review of the current head and neck cancer referral guidelines is recommended, along with further data collection for comparison.
Introduction: Sepsis in cancer patients is associated with higher mortality rates than non-cancer patients. As a whole, hematological or solid tumor cancers have not demonstrated a prognostic link to sepsis survival rates in intensive care units (ICU), however poor-prognosis solid tumours (less than 25% 5-year survival) have not been investigated. This study examined ICU mortality rate and its predictive factors of patients with sepsis and poor-prognosis solid tumors in comparison to patients with higher prognosis solid tumours. Methods: A 6-year retrospective chart review of 79 patients with sepsis and solid tumour cancers and/or metastatic cancers admitted to the ICU was conducted. Information regarding mortality rate within 14 days, length of ICU stay, incidence of intubation, and other primary reasons for ICU admission was collected. Data was analysed using logistic regression. Results: Logistic regression results showed intubation as the only significant factor contributing to patient mortality (p < .001), with the odds of mortality being 12.3 times higher for intubated than non-intubated patients. Five-year cancer survival rate was the second best predictor (p = .082), while age, sex, and metastasis were also not significant predictive factors for survival. Intubated patients with poor prognosis cancers had the lowest survival chance as further indicated by the 16 patients who met this criterion, of which 14 died within two weeks of ICU admission. Conclusion: The fact that poor prognosis cancers in sepsis were not significantly predictive of ICU mortality supports current literature regarding solid tumors in general, while intubation being a significant predictor for mortality in patients with sepsis and cancer regardless of type builds on previous research. A limitation of this study is the relative low number of included cases with poor-prognosis cancer types. Further evaluation is needed to understand the implications of our results for end-of-life care and ICU admission for patients with these characteristics.
Norovirus is a predominant cause of infectious gastroenteritis in countries worldwide [1–5]. It accounts for approximately 50% of acute gastroenteritis (AGE) and >90% of viral gastroenteritis outbreaks [6, 7]. The incubation period ranges between 10 and 48 h and illness duration is generally 1–3 days with self-limiting symptoms; however, this duration is often longer (e.g. 4–6 days) in vulnerable populations such as hospital patients or young children [2, 8]. Symptomatic infection of norovirus presents as acute vomiting, diarrhoea, abdominal cramps and nausea, with severe vomiting and diarrhoea (non-bloody) being most common [2, 5, 9].
In the National Institutes of Health (NIH) Clinical Center, patients colonized or infected with vancomycin-resistant Enterococcus (VRE) are placed in contact isolation until they are deemed “decolonized,” defined as having 3 consecutive perirectal swabs negative for VRE. Some decolonized patients later develop recurrent growth of VRE from surveillance or clinical cultures (ie, “recolonized”), although that finding may represent recrudescence or new acquisition of VRE. We describe the dynamics of VRE colonization and infection and their relationship to receipt of antibiotics.
In this retrospective cohort study of patients at the National Institutes of Health Clinical Center, baseline characteristics were collected via chart review. Antibiotic exposure and hospital days were calculated as proportions of VRE decolonized days. Using survival analysis, we assessed the relationship between antibiotic exposure and time to VRE recolonization in a subcohort analysis of 72 decolonized patients.
In total, 350 patients were either colonized or infected with VRE. Among polymerase chain reaction (PCR)-positive, culture (Cx)-negative (PCR+/Cx−) patients, PCR had a 39% positive predictive value for colonization. Colonization with VRE was significantly associated with VRE infection. Among 72 patients who met decolonization criteria, 21 (29%) subsequently became recolonized. VRE recolonization was 4.3 (P = .001) and 2.0 (P = .22) times higher in patients with proportions of antibiotic days and antianaerobic antibiotic days above the median, respectively.
Colonization is associated with clinical VRE infection and increased mortality. Despite negative perirectal cultures, re-exposure to antibiotics increases the risk of VRE recolonization.
Lung surfactant (LS), a thin layer of phospholipids and proteins inside the alveolus of the lung is the first biological barrier to inhaled nanoparticles (NPs). LS stabilizes and protects the alveolus during its continuous compression and expansion by fine-tuning the surface tension at the air-water interface. Previous modelling studies have reported the biophysical function of LS monolayer and its role, but many open questions regarding the consequences and interactions of airborne nano-sized particles with LS monolayer remain. In spite of gold nanoparticles (AuNPs) having a paramount role in biomedical applications, the understanding of the interactions between bare AuNPs (as pollutants) and LS monolayer components still unresolved. Continuous inhalation of NPs increases the possibility of lung ageing, reducing the normal lung functioning and promoting lung malfunction, and may induce serious lung diseases such as asthma, lung cancer, acute respiratory distress syndrome, and more. Different medical studies have shown that AuNPs can disrupt the routine lung functions of gold miners and promote respiratory diseases. In this work, coarse-grained molecular dynamics simulations are performed to gain an understanding of the interactions between bare AuNPs and LS monolayer components at the nanoscale. Different surface tensions of the monolayer are used to mimic the biological process of breathing (inhalation and exhalation). It is found that the NP affects the structure and packing of the lipids by disordering lipid tails. Overall, the analysed results suggest that bare AuNPs impede the normal biophysical function of the lung, a finding that has beneficial consequences to the potential development of treatments of various respiratory diseases.
As renewable energy supply chains have grown increasingly globalized, national clean energy transitions have become highly influenced by international dynamics. However, these dynamics are themselves collectively shaped by domestic policy that drives the deployment of renewables. While spatial spillovers of domestic renewable energy policies have been studied on an aggregate level regarding policy diffusion or the flows of technology across countries, implications on an actor-level have been largely neglected. This article addresses this gap by analyzing global patterns of market openings for wind, solar PV, and biomass, focusing on the role of private project developers in developing countries. We use a mixed method design, based on a newly merged dataset encompassing eighty countries, and on interviews with pioneering project developers. Results highlight how patterns in market openings are shaped considerably by technology characteristics. Further, empirical results show international private developers are a key first mover in many developing countries. We explore drivers for this internationalization trend, including the impact of international developers' home country policies and the accumulation of tacit knowledge from home country markets for market openings abroad. Finally, we discuss implications for industrial policy and argue for further research on global spillovers of national policies on the actor-level.
Detecting gastrointestinal (GI) infection transmission among men who have sex with men (MSM) in England is complicated by a lack of routine sexual behavioural data. We investigated whether gender distributions might generate signals for increased transmission of GI pathogens among MSM. We examined the percentage male of laboratory-confirmed patient-episodes for patients with no known travel history for 10 GI infections of public health interest in England between 2003 and 2013, stratified by age and region. An adult male excess was observed for Shigella spp. (annual maximum 71% male); most pronounced for those aged 25–49 years and living in London, Brighton and Manchester. An adult male excess was observed every year for Entamoeba histolytica (range 59.8–76.1% male), Giardia (53.1–57.6%) and Campylobacter (52.1–53.5%) and for a minority of years for hepatitis A (max. 69.8%) and typhoidal salmonella (max. 65.7%). This approach generated a signal for excess male episodes for six GI pathogens, including a characterised outbreak of Shigella among MSM. Stratified analyses by geography and age group were consistent with MSM transmission for Shigella. Optimisation and routine application of this technique by public health authorities elsewhere might help identify potential GI infection outbreaks due to sexual transmission among MSM, for further investigation.
Electron and proton microprobes, along with electron backscatter diffraction (EBSD) analysis were used to study the microstructure of the contemporary Al–Cu–Li alloy AA2099-T8. In electron probe microanalysis, wavelength and energy dispersive X-ray spectrometry were used in parallel with soft X-ray emission spectroscopy (SXES) to characterize the microstructure of AA2099-T8. The electron microprobe was able to identify five unique compositions for constituent intermetallic (IM) particles containing combinations of Al, Cu, Fe, Mn, and Zn. A sixth IM type was found to be rich in Ti and B (suggesting TiB2), and a seventh IM type contained Si. EBSD patterns for the five constituent IM particles containing Al, Cu, Fe, Mn, and Zn indicated that they were isomorphous with four phases in the 2xxx series aluminium alloys including Al6(Fe, Mn), Al13(Fe, Mn)4 (two slightly different compositions), Al37Cu2Fe12 and Al7Cu2Fe. SXES revealed that Li was present in some constituent IM particles. Al SXES mapping revealed an Al-enriched (i.e., Cu, Li-depleted) zone in the grain boundary network. From the EBSD analysis, the kernel average misorientation map showed higher levels of localized misorientation in this region, suggesting greater deformation or stored energy. Proton-induced X-ray emission revealed banding of the TiB2 IM particles and Cu inter-band enrichment.
Introduction: The field of Clinical Informatics (CI) and specifically the electronic health record, has been identified as a key facilitator to achieve a sustainable evidence-based healthcare system for the future. International graduate medical education programs have been challenged to ensure their trainees are provided with appropriate skills to deliver effective and efficient healthcare in an evolving environment. This study explored how international Emergency Medicine (EM) specialist training standards address training in relevant areas of CI. Methods: A list of categories of CI competencies relative to EM was developed following a thematic review of published references documenting CI curriculum and competencies. Publically available, published documents outlining core content, curriculum and competencies from international organizations responsible for specialty graduate medical education and/or credentialing in EM for the United States, Canada, Australasia, the United Kingdom and Europe. These EM training standards were reviewed to identify inclusion of topics related to the relevant categories of CI competencies. Results: A total of 23 EM curriculum documents were included in the thematic analysis. Curricula content related to critical appraisal/evidence based medicine, leadership, quality improvement and privacy/security were included in all EM curricula. The CI topics related to fundamental computer skills, computerized provider order entry and patient-centered informatics were only included in the EM curricula documents for the United States and were absent for each other organization. Conclusion: There is variation in the CI related content of the international EM specialty training standards which were reviewed. Given the increasing importance of CI in the future delivery of healthcare, organizations responsible for training and credentialing specialist emergency physicians must ensure their training standards incorporate relevant CI content, thus ensuring their trainees gain competence in essential aspects of CI.
Commercial point-of-care (POC) diagnostic tests for Group A Streptococcus, Streptococcus pneumoniae, and influenza virus have large potential diagnostic and financial impact. Many published reports on test performance, often funded by diagnostics companies, are prone to bias. The Standards for Reporting of Diagnostic Accuracy (STARD 2015) are a protocol to encourage accurate, transparent reporting. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool evaluates risk of bias and transportability of results. We used these tools to evaluate diagnostic test accuracy studies of POC studies for three respiratory pathogens. For the 96 studies analysed, compliance was <25% for 14/34 STARD 2015 standards, and 3/7 QUADAS-2 domains showed a high risk of bias. All reports lacked reporting of at least one criterion. These biases should be considered in the interpretation of study results.
A new species of Begonia (B. lecongkietii N.S.Lý & M.Hughes) is described from Mount Dầu in the South Central Coast Region, Vietnam, an area with an abundance of recently described endemic plant taxa. The new species is allied to Begonia lamxayana Souvann., which occurs 600 km away in Laos, differing chiefly in having larger villose tepals with an undulate margin and larger androecium with 86–116 (versus 20–30) stamens. Begonia lecongkietii is considered Critically Endangered, owing to its small area of occupancy and decline of habitat quality.
A revision of Begonia sect. Symbegonia, endemic to New Guinea, is presented, with descriptions of five new species (B. arauensis M.Hughes, B. asaroensis J.Gagul, B. erodiifolia Sands, B. mimikaensis Sands and B. vinkii Sands). There are 18 species now recognised, and a key is provided for their identification. Ten of the species are assessed to belong to the IUCN category Data Deficient, and eight to Least Concern.
The management of human immunodeficiency virus (HIV) infection continues to evolve rapidly. Amazing advances have been made in therapy of primary infection, prevention of opportunistic infections, and prevention of perinatal transmission since the first cases of acquired immune deficiency syndrome (AIDS) were described in 1981. Perinatal transmission rates have decreased from 20–30% early in the epidemic to < 1% in high-income countries with the use of antiretroviral therapy and scheduled cesarean delivery.
Hughes defined a class of groups that act as local similarities on compact ultrametric spaces. Guba and Sapir had previously defined braided diagram groups over semigroup presentations. The two classes of groups share some common characteristics: both act properly by isometries on CAT(0) cubical complexes, and certain groups in both classes have type F∞, for instance.
Here we clarify the relationship between these families of groups: the braided diagram groups over tree-like semigroup presentations are precisely the groups that act on compact ultrametric spaces via small similarity structures. The proof can be considered a generalization of the proof that Thompson's group V is a braided diagram group over a tree-like semigroup presentation.
We also prove that certain additional groups, such as the Houghton groups Hn, and QAut(T2,c), lie in both classes.
In , Hughes described a class of groups that act as homeomorphisms on compact ultrametric spaces. Fix a compact ultrametric space X. The essence of the idea was to associate to X a finite similarity structure, which is a function that associates to each ordered pair of balls B1,B2 ⊆ X a finite set SimX(B1,B2) of surjective similarities from B1 to B2. (A similarity is a map that stretches or contracts distances by a fixed constant.) The finite sets SimX(B1,B2) are assumed to have certain desirable closure properties (such as closure under composition). A homeomorphism h : X → X is said to be locally determined by SimX if each x ∈ X has a ball neighborhood B with the property that h(B) is a ball and the restriction of h to B agrees with one of the local similarities σ ∈ SimX(B, h(B)). The collection of all homeomorphisms that are locally determined by SimX forms a group under composition. We will call such a group an FSS group (finite similarity structure group) for short. Hughes  proved that each FSS group has the Haagerup property, and even acts properly on a CAT(0) cubical complex. In , the authors described a class of FSS groups that have type F∞. That class includes Thompson's group V, and the main theorem of  is best understood as a generalization of , where Brown originally showed that V has type F∞.
We demonstrate an application of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images to detect and monitor supraglacial lakes on glaciers in the Mount Everest region in Tibet (Xizang) and Nepal. ASTER offers powerful capabilities to monitor supraglacial lakes in terms of (1) surface area, growth and disappearance (spatial resolution =15m), (2) turbidity (15m resolution), and (3) temperature (90m resolution). Preliminary results show an overall similarity of supraglacial lakes on three glaciers. Lakes have widely varying turbidity as indicated by color in visible/near-infrared bands 1–3, the largest lakes being bright blue (highly turbid), cold (near 0°C) and hydraulically connected with other lakes and supraglacial streams, while small lakes are mostly darkblue (relatively clear water), warmer (>4°C), and appear hydraulically isolated. High levels of turbidity in supraglacial lakes indicate high rates of meltwater input from streams or erosion of ice cliffs, and thus are an indirect measure relating to the activity and hydraulic integration of the lake with respect to other lakes and streams in the glacier.
Our objective is to measure the mechanical properties of anisotropic ice of the EPICA ice core, from Dome Concordia, Antarctica, through the full depth of the borehole in deformation experiments under simulated ice-sheet conditions of temperature and pressure. We propose to undertake experiments on the EPICA core using both a conventional triaxial-test apparatus and a new, true, triaxial-test apparatus incorporating automated tomographic imaging of the ice-fabric evolution during deformation. We present the design of this new apparatus together with our testing methodology for EPICA ice. The new apparatus is capable of deforming an ice specimen, up to 200 mm × 100 mm × 40 mm, under servo-controlled biaxial loading with a superimposed confining pressure of 50 MPa and at temperatures down to –40°C. Highly unusual problems arising from the true triaxial nature of the apparatus and tomographic imaging are discussed.