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We present an overview of the Middle Ages Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey, a Large Program on the European Southern Observatory Very Large Telescope. MAGPI is designed to study the physical drivers of galaxy transformation at a lookback time of 3–4 Gyr, during which the dynamical, morphological, and chemical properties of galaxies are predicted to evolve significantly. The survey uses new medium-deep adaptive optics aided Multi-Unit Spectroscopic Explorer (MUSE) observations of fields selected from the Galaxy and Mass Assembly (GAMA) survey, providing a wealth of publicly available ancillary multi-wavelength data. With these data, MAGPI will map the kinematic and chemical properties of stars and ionised gas for a sample of 60 massive (
${>}7 \times 10^{10} {\mathrm{M}}_\odot$
) central galaxies at
$0.25 < z <0.35$
in a representative range of environments (isolated, groups and clusters). The spatial resolution delivered by MUSE with Ground Layer Adaptive Optics (
$0.6-0.8$
arcsec FWHM) will facilitate a direct comparison with Integral Field Spectroscopy surveys of the nearby Universe, such as SAMI and MaNGA, and at higher redshifts using adaptive optics, for example, SINS. In addition to the primary (central) galaxy sample, MAGPI will deliver resolved and unresolved spectra for as many as 150 satellite galaxies at
$0.25 < z <0.35$
, as well as hundreds of emission-line sources at
$z < 6$
. This paper outlines the science goals, survey design, and observing strategy of MAGPI. We also present a first look at the MAGPI data, and the theoretical framework to which MAGPI data will be compared using the current generation of cosmological hydrodynamical simulations including EAGLE, Magneticum, HORIZON-AGN, and Illustris-TNG. Our results show that cosmological hydrodynamical simulations make discrepant predictions in the spatially resolved properties of galaxies at
$z\approx 0.3$
. MAGPI observations will place new constraints and allow for tangible improvements in galaxy formation theory.
The paper describes an ongoing effort in developing a declarative system for supporting operators in the Nuclear Power Plant (NPP) control room. The focus is on two modules: diagnosis and explanation of events that happened in NPPs. We describe an Answer Set Programming (ASP) representation of an NPP, which consists of declarations of state variables, components, their connections, and rules encoding the plant behavior. We then show how the ASP program can be used to explain the series of events that occurred in the Three Mile Island, Unit 2 (TMI-2) NPP accident, the most severe accident in the USA nuclear power plant operating history. We also describe an explanation module aimed at addressing answers to questions such as “why an event occurs?” or “what should be done?” given the collected data.
Background: Biallelic variants in POLR1C are associated with POLR3-related leukodystrophy (POLR3-HLD), or 4H leukodystrophy (Hypomyelination, Hypodontia, Hypogonadotropic Hypogonadism), and Treacher Collins syndrome (TCS). The clinical spectrum of POLR3-HLD caused by variants in this gene has not been described. Methods: A cross-sectional observational study involving 25 centers worldwide was conducted between 2016 and 2018. The clinical, radiologic and molecular features of 23 unreported and previously reported cases of POLR3-HLD caused by POLR1C variants were reviewed. Results: Most participants presented between birth and age 6 years with motor difficulties. Neurological deterioration was seen during childhood, suggesting a more severe phenotype than previously described. The dental, ocular and endocrine features often seen in POLR3-HLD were not invariably present. Five patients (22%) had a combination of hypomyelinating leukodystrophy and abnormal craniofacial development, including one individual with clear TCS features. Several cases did not exhibit all the typical radiologic characteristics of POLR3-HLD. A total of 29 different pathogenic variants in POLR1C were identified, including 13 new disease-causing variants. Conclusions: Based on the largest cohort of patients to date, these results suggest novel characteristics of POLR1C-related disorder, with a spectrum of clinical involvement characterized by hypomyelinating leukodystrophy with or without abnormal craniofacial development reminiscent of TCS.
We study the inverse boundary value problem for fractional diffusion in a multilayer composite medium. Given data in the right boundary of the second layer, the problem is to recover the temperature distribution in the first layer, which is inaccessible for measurement. The problem is ill-posed and we propose a Fourier spectral approach to achieve Hölder approximations. The convergence analysis is performed in both the $L^{2}$- and $L^{\infty }$-settings.
To assess general medical residents’ familiarity with antibiograms using a self-administered survey
DESIGN
Cross-sectional, single-center survey
PARTICIPANTS
Residents in internal medicine, family medicine, and pediatrics at an academic medical center
METHODS
Participants were administered an anonymous survey at our institution during regularly scheduled educational conferences between January and May 2012. Questions collected data regarding demographics, professional training; further open-ended questions assessed knowledge and use of antibiograms regarding possible pathogens, antibiotic regimens, and prescribing resources for 2 clinical vignettes; a series of directed, closed-ended questions followed. Bivariate analyses to compare responses between residency programs were performed.
RESULTS
Of 122 surveys distributed, 106 residents (87%) responded; internal medicine residents accounted for 69% of responses. More than 20% of residents could not accurately identify pathogens to target with empiric therapy or select therapy with an appropriate spectrum of activity in response to the clinical vignettes; correct identification of potential pathogens was not associated with selecting appropriate therapy. Only 12% of respondents identified antibiograms as a resource when prescribing empiric antibiotic therapy for scenarios in the vignettes, with most selecting the UpToDate online clinical decision support resource or The Sanford Guide. When directly questioned, 89% reported awareness of institutional antibiograms, but only 70% felt comfortable using them and only 44% knew how to access them.
CONCLUSIONS
When selecting empiric antibiotics, many residents are not comfortable using antibiograms as part of treatment decisions. Efforts to improve antibiotic use may benefit from residents being given additional education on both infectious diseases pharmacotherapy and antibiogram utilization.
Carbonated calcium apatites doped with a monovalent cation (Li+, Na+, or K+) or a divalent cation (Mg2+ or Zn2+) were prepared in aqueous solution and analysed by powder X-ray diffraction, inductively coupled plasma atomic emission spectroscopy and infrared spectroscopy. The hypothesis that the location of carbonate in the apatite structure, either in place of hydroxide ions in the c-axis channels (A-type substitution) or in place of phosphate (B-type substitution), is affected by the solution energetics of the cation (specifically its enthalpy of hydration) was strengthened by the observation of larger amounts of Atype carbonate in apatites containing the monovalent cations in aqueous solution. It is shown that cations with low negative enthalpies of hydration favour A-type substitution, whereas cations with higher negative hydration enthalpies, such as divalent cations (Mg2+, Zn2+), favour B-type substitution.
Central nervous system infections (CNSI) are a leading cause of death and long-term disability in children. Using ICD-10 data from 2005 to 2015 from three central hospitals in Ho Chi Minh City (HCMC), Vietnam, we exploited generalized additive mixed models (GAMM) to examine the spatial-temporal distribution and spatial and climatic risk factors of paediatric CNSI, excluding tuberculous meningitis, in this setting. From 2005 to 2015, there were 9469 cases of paediatric CNSI; 33% were ⩽1 year old at admission and were mainly diagnosed with presumed bacterial CNSI (BI) (79%), the remainder were >1 year old and mainly diagnosed with presumed non-bacterial CNSI (non-BI) (59%). The urban districts of HCMC in proximity to the hospitals as well as some outer districts had the highest incidences of BI and non-BI; BI incidence was higher in the dry season. Monthly BI incidence exhibited a significant decreasing trend over the study. Both BI and non-BI were significantly associated with lags in monthly average temperature, rainfall, and river water level. Our findings add new insights into this important group of infections in Vietnam, and highlight where resources for the prevention and control of paediatric CNSI should be allocated.
Information about viral acute respiratory infections (ARIs) is essential for prevention, diagnosis and treatment, but it is limited in tropical developing countries. This study described the clinical and epidemiological characteristics of ARIs in children hospitalized in Vietnam. Nasopharyngeal samples were collected from children with ARIs at Ho Chi Minh City Children's Hospital 2 between April 2010 and May 2011 in order to detect respiratory viruses by polymerase chain reaction. Viruses were found in 64% of 1082 patients, with 12% being co-infections. The leading detected viruses were human rhinovirus (HRV; 30%), respiratory syncytial virus (RSV; 23·8%), and human bocavirus (HBoV; 7·2%). HRV was detected all year round, while RSV epidemics occurred mainly in the rainy season. Influenza A (FluA) was found in both seasons. The other viruses were predominant in the dry season. HRV was identified in children of all age groups. RSV, parainfluenza virus (PIV) 1, PIV3 and HBoV, and FluA were detected predominantly in children aged <6 months, 6–12 months, 12–24 months, and >24 months, respectively. Significant associations were found between PIV1 with croup (P < 0·005) and RSV with bronchiolitis (P < 0·005). HBoV and HRV were associated with hypoxia (P < 0·05) and RSV with retraction (P < 0·05). HRV, RSV, and HBoV were detected most frequently and they may increase the severity of ARIs in children.
Molecular epidemiology and clinical impact of human rhinovirus (HRV) are not well documented in tropical regions. This study compared the clinical characteristics of HRV to other common viral infections and investigated the molecular epidemiology of HRV in hospitalized children with acute respiratory infections (ARIs) in Vietnam. From April 2010 to May 2011, 1082 nasopharyngeal swabs were screened for respiratory viruses by PCR. VP4/VP2 sequences of HRV were further characterized. HRV was the most commonly detected virus (30%), in which 70% were diagnosed as either pneumonia or bronchiolitis. Children with single HRV infections presented with significantly higher rate of hypoxia than those infected with respiratory syncytial virus or parainfluenza virus (PIV)-3 (12·4% vs. 3·8% and 0%, respectively, P < 0·05), higher rate of chest retraction than PIV-1 (57·3% vs. 34·5%, P = 0·028), higher rate of wheezing than influenza A (63·2% vs. 42·3%, P = 0·038). HRV-C did not differ to HRV-A clinically. The genetic diversity and changes of types over time were observed and may explain the year-round circulation of HRV. One novel HRV-A type was discovered which circulated locally for several years. In conclusion, HRV showed high genetic diversity and was associated with significant morbidity and severe ARIs in hospitalized children.
Seasonal as well as weekly cycles in suicide have been described, replicated and poorly understood for a long time. In Western countries, suicides are typically least frequent on weekends and most frequent on Mondays and Tuesdays. To improve understanding of this phenomenon a strategy is required which focuses on anomalous findings beyond the regular patterns. Here, we focused on instances where the weekly suicide patterns disappear or are interrupted.
Methods.
We used data from Swiss and Austrian mortality statistics for the periods 1969–2010 and 1970–2010, respectively. First, the data were cross-tabulated by days of the week and the available socio-demographic information (sex, age, religious affiliation and region). Second, time series of cumulated daily frequencies of suicide were analysed by seasonal Autoregressive Integrated Moving Average (ARIMA) models which included intervention effects accounting for Easter and Pentecost (Whit) holidays.
Results.
First, the cross tabulations showed that weekly cycles may be smoothed above all in young persons and smoothed in drowning, jumping and car gas exhaustion suicides. Second, the ARIMA analyses displayed occasional preventive effects for holidays Saturdays and Sundays, and more systematic effects for holiday Mondays. There were no after effects on Tuesdays following holiday Mondays.
Conclusions.
In general, the weekend dip and the Monday backlog effect in suicide show striking similarities to the Advent season effect and are interpretable within the same template. The turning points between low and high frequencies possibly provide promising frames for the timing of prevention activities.
Non-typhoidal Salmonella are an important but poorly characterized cause of paediatric diarrhoea in developing countries. We conducted a hospital-based case-control study in children aged <5 years in Ho Chi Minh City to define the epidemiology and examine risk factors associated with Salmonella diarrhoeal infections. From 1419 diarrhoea cases and 571 controls enrolled between 2009 and 2010, 77 (5·4%) diarrhoea cases were stool culture-positive for non-typhoidal Salmonella. Salmonella patients were more likely to be younger than controls (median age 10 and 12 months, respectively) [odds ratio (OR) 0·97; 95% confidence interval (CI) 0·94–0·99], to report a recent diarrhoeal contact (8·1% cases, 1·8% controls; OR 5·98, 95% CI 1·8–20·4) and to live in a household with >2 children (cases 20·8%, controls 10·2%; OR 2·32, 95% CI 1·2–4·7). Our findings indicate that Salmonella are an important cause of paediatric gastroenteritis in this setting and we suggest that transmission may occur through direct human contact in the home.
EuroRotaNet, a laboratory network, was established in order to determine the diversity of co-circulating rotavirus strains in Europe over three or more rotavirus seasons from 2006/2007 and currently includes 16 countries. This report highlights the tremendous diversity of rotavirus strains co-circulating in the European population during three years of surveillance since 2006/2007 and points to the possible origins of these strains including genetic reassortment and interspecies transmission. Furthermore, the ability of the network to identify strains circulating with an incidence of ⩾1% allowed the identification of possible emerging strains such as G8 and G12 since the beginning of the study; analysis of recent data indicates their increased incidence. The introduction of universal rotavirus vaccination in at least two of the participating countries, and partial vaccine coverage in some others may provide data on diversity driven by vaccine introduction and possible strain replacement in Europe.
Multiple gastroenteritis outbreaks occurred between 25 and 31 July 2006 in 10 workplace canteens in south-western Finland. One vegetable processing plant provided raw vegetables to all the canteens. We conducted cohort studies in the three most visited canteens and environmental investigations in the kitchens and the plant. Patients' stools, food, water and environmental samples were tested for enteric bacteria and viruses. Of the three canteens, 150/273 respondents (response rate 82%) had gastroenteritis. Consumption of mixed raw vegetables was significantly associated with the illness but no single vegetable explains the outbreak. An identical norovirus GII.1 genotype was detected from all genotyped patient samples. Water, food, and environmental samples were negative for norovirus. The facilities had appropriate hygienic conditions and no staff member had gastroenteritis prior to the outbreak. Tracing back the vegetables to the farm level proved unsuccessful. This was the largest foodborne norovirus outbreak in Finland.
The boundary-element method is used to solve Stokes equations for periodic arrays of force-free and torque-free rigid particles. Simple cubic arrays of spheres, spheroids, cubes, and clusters of spheres are subjected to a bulk simple shearing flow. The effective volume-averaged stress tensor for the suspension and the detailed velocity and stress fields throughout the Newtonian suspending fluid are calculated. We find that even crude meshes give very good volume-averaged results, but fine meshes are required to track local minima and maxima in the stress field. For simple cubic arrays of spheres, the boundary-element results are in excellent agreement with the analytical viscosity predictions of Nunan & Keller (1984). Even at the highest concentration of solids studied, no significant normal stress differences were observed, in agreement with Nunan & Keller's results (1984). Up to moderate concentrations of particles, the volume-averaged properties of the suspension display only a weak dependence on the particle geometry. Suspensions of spheroids and cubes behave approximately as suspensions of spheres on the average despite large differences in the local micromechanics of stress and velocity fields. Simple cubic arrays of clusters of spheres tend to behave on a macroscopic level as a cubic array of spheres whose effective volume fraction is about 150% of the total volume fraction of the spheres in the clusters.
The swimming of a flagellar micro-organism by the propagation of helical waves along its flagellum is analysed by a boundary-element method. The method is not restricted to any particular geometry of the organism nor does it assume a specific wave motion for the flagellum. However, only results for an organism with a spherical or ellipsoidal cell body and a helically beating flagellum are presented here.
With regard to the flagellum, it is concluded that the optimum helical wave (amplitude α and wavenumber k) has αk ≈ 1 (pitch angle of 45°) and that for the optimum flagellar length L/A = 10 (L being the flagellar length, A being the radius of the assumed spherical cell body) the optimum number of wavelengths Nλ is about 1.5. Furthermore there appears to be no optimal value for the flagellar radius a, with the thinner flagella being favoured. These conclusions show excellent quantitative agreement with those of slender-body theory.
For the case of an ellipsoidal cell body, the optimum aspect ratios B/A and C/A of the ellipsoid are about 0.7 and 0.3 respectively; A, B and C are the principal radii of the ellipsoid. These and all of the above conclusions show good qualitative agreement with experimental observations of efficiently swimming micro-organisms.
Poly-β-hydroxybuterate (PHB), a biodegradable polyester, is accumulated as a storage compound in many species of bacteria. It belongs to a class of polymers called polyhydroxyalkanoates (PHAs). PHA's were originally identified in 1923.However these polymers first came to the attention of industry in the early 1980's when they were recognized as having thermoplastic properties.Monsanto currently markets a form of PHA produced via fermentation under the trade name Biopol™. It is used to make biodegradable plastic products such as credit cards, bottles and disposable drinking cups. However fermentation is an expensive route to production. The use of crop plants genetically engineered to produce PHA's could provide a less expensive source of the plastic and therefore a more attractive alternative to traditional non-biodegradable petrochemical derived plastics. PHB production in plants was first demonstrated in 1992 in transgenic Arabidopsis thaliana by Chris Somerville and coworkers. They showed that PHB production was tolerated by the plant if it was targeted to the chloroplasts.
Effect of low level doping of boron and phosphorus on the properties of amorphous silicon films (a-Si:H) was studied. Doping level of both boron and phosphorus was in the range of 1017 atoms/cm3. Apparent improvement in the stability of dark and photoconductivity of a-Si:H films upon low level doping does not result from the elimination of light-induced defects. The stability of the dark and photoconductivity upon doping is an indication of pinning of the Fermi level.
Carbon grading in the buffer layer at the p/i interface increases the open circuit voltage of both p-i-n and n-i-p amorphous silicon solar cells. We propose that carbon grading enlarges the electric field and reduces the electron tunneling at the p/i interface.
Amorphous hydrogenated silicon carbide alloy films (a-SiC:H) were produced by the decomposition of methane and silane in a glow discharge deposition system. A deposition rate of 13 Å/sec was achieved for good quality films. Amorphous SiC:H films of p+ type and n+ type of a band gap of 1.86 eV and 1.8 eV and the activation energy of 0.4 eV and 0.23 eV, respectively were obtained. Results show that p+ type and n+ type a-SiC:H films can be good window layers and good diffusion barriers for indium in polyimide/metal/n-i-p(p-i-n)/ITO amorphous silicon solar cells.