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The ‘Vulnerable’ Swinhoe’s Rail Coturnicops exquisitus is believed to occur in only two regions in Russia’s Far East and China’s Heilongjiang province, separated by more than 1,000 km. Recent observations suggest that the Amur region, situated between the two known populations, might be inhabited by this secretive species as well. As the species is rather similar in appearance and field characteristics to its Nearctic sister taxon, the Yellow Rail C. noveboracensis, and almost all field records relate to flushed individuals in flight, we aimed to complement the field observations by genetic evidence. Samples were obtained from four individuals and one eggshell and their mitochondrial cytochrome b genes were amplified and sequenced. The genetic analyses unequivocally confirmed that swab samples and eggshell were attributable to Swinhoe’s Rail, thus constituting the first known breeding record of this species for 110 years. It is therefore likely that the individuals observed in the field also belonged to this species. It seems possible that Swinhoe’s Rail is more widely distributed in the Amur region and was overlooked in the past, possibly due to a misleading description of its calls in the literature.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
Anomalies in the abundance measurements of short lived radionuclides in meteorites indicate that the protosolar nebulae was irradiated by a large number of energetic particles (E≳ 10 MeV), often called solar cosmic rays. The particle flux of the contemporary Sun cannot explain these anomalies, but, similar to T Tauri stars, the young Sun was more active and probably produced enough high energy particles. However, the stellar particle (SP) flux of young stars is essentially unknown. We model the impact of high-energy ionization sources on the chemistry of the circumstellar environment (disks and envelopes). The model includes X-ray radiative transfer and makes use of particle transport models to calculate the individual molecular hydrogen ionization rates. We study the impact on the chemistry via the ionization tracers HCO+ and N2H+. We argue that spatially resolved observations of those molecules combined with detailed models allow for disentangling the contribution of the individual high-energy ionization sources and to put constraints on the SP flux in young stars.
Guidelines for a healthy diet aim to decrease the risk of chronic diseases. It is unclear as to what extent a healthy diet is also an environmentally friendly diet. In the Dutch sub-cohort of the European Prospective Investigation into Cancer and Nutrition, the diet was assessed with a 178-item FFQ of 40 011 participants aged 20–70 years between 1993 and 1997. The WHO’s Healthy Diet Indicator (HDI), the Dietary Approaches to Stop Hypertension (DASH) score and the Dutch Healthy Diet index 2015 (DHD15-index) were investigated in relation to greenhouse gas (GHG) emissions, land use and all-cause mortality risk. GHG emissions were associated with HDI scores (−3·7 % per sd increase (95 % CI −3·4, −4·0) for men and −1·9 % (95 % CI −0·4, −3·4) for women), with DASH scores in women only (1·1 % per sd increase, 95 % CI 0·9, 1·3) and with DHD15-index scores (−2·5 % per sd increase (95 % CI −2·2, −2·8) for men and −2·0 % (95 % CI −1·9, −2·2) for women). For all indices, higher scores were associated with less land use (ranging from −1·3 to −3·1 %). Mortality risk decreased with increasing scores for all indices. Per sd increase of the indices, hazard ratios for mortality ranged from 0·88 (95 % CI 0·82, 0·95) to 0·96 (95 % CI 0·92, 0·99). Our results showed that adhering to the WHO and Dutch dietary guidelines will lower the risk of all-cause mortality and moderately lower the environmental impact. The DASH diet was associated with lower mortality and land use, but because of high dairy product consumption in the Netherlands it was also associated with higher GHG emissions.
The breeding areas of the Critically Endangered Slender-billed Curlew Numenius tenuirostris are all but unknown, with the only well-substantiated breeding records being from the Omsk province, western Siberia. The identification of any remaining breeding population is of the highest priority for the conservation of any remnant population. If it is extinct, the reliable identification of former breeding sites may help determine the causes of the species’ decline, in order to learn wider conservation lessons. We used stable isotope values in feather samples from juvenile Slender-billed Curlews to identify potential breeding areas. Modelled precipitation δ2H data were compared to feather samples of surrogate species from within the potential breeding range, to produce a calibration equation. Application of this calibration to samples from 35 Slender-billed Curlew museum skins suggested they could have originated from the steppes of northern Kazakhstan and part of southern Russia between 48°N and 56°N. The core of this area was around 50°N, some way to the south of the confirmed nesting sites in the forest steppes. Surveys for the species might be better targeted at the Kazakh steppes, rather than around the historically recognised nest sites of southern Russia which might have been atypical for the species. We consider whether agricultural expansion in this area may have contributed to declines of the Slender-billed Curlew population.
The Protoplanetary Discussions conference—held in Edinburgh, UK, from 2016 March 7th–11th—included several open sessions led by participants. This paper reports on the discussions collectively concerned with the multi-physics modelling of protoplanetary discs, including the self-consistent calculation of gas and dust dynamics, radiative transfer, and chemistry. After a short introduction to each of these disciplines in isolation, we identify a series of burning questions and grand challenges associated with their continuing development and integration. We then discuss potential pathways towards solving these challenges, grouped by strategical, technical, and collaborative developments. This paper is not intended to be a review, but rather to motivate and direct future research and collaboration across typically distinct fields based on community-driven input, to encourage further progress in our understanding of circumstellar and protoplanetary discs.
We present a new determination of the solar nitrogen abundance making use of 3D hydrodynamical modelling of the solar photosphere, which is more physically motivated than traditional static 1D models. We selected suitable atomic spectral lines, relying on equivalent width measurements already existing in the literature. For atmospheric modelling we used the co5bold 3D radiation hydrodynamics code. We investigated the influence of both deviations from local thermodynamic equilibrium (non-LTE effects) and photospheric inhomogeneities (granulation effects) on the resulting abundance. We also compared several atlases of solar flux and centre-disc intensity presently available. As a result of our analysis, the photospheric solar nitrogen abundance is A(N) = 7.86 ± 0.12.
Both background rotation and small depths are said to enforce the two-dimensionality of flows. In the current paper, we describe a systematic study of the two-dimensionality of a shallow monopolar vortex subjected to background rotation. Using a perturbation analysis of the Navier–Stokes equations for small aspect ratio (with the fluid depth and a typical radial length scale of the vortex), we found nine different regimes in the parameter space where the flow is governed to lowest order by different sets of equations. From the properties of these sets of equations, it was determined that the flow can be considered as quasi-two-dimensional in only five of the nine regimes. The scaling of the velocity components as given by these sets of equations was compared with results from numerical simulations to find the actual boundaries of the different regimes in the parameter space (), where is the Ekman boundary layer thickness and is the equivalent boundary layer thickness for a monopolar vortex without background rotation. Even though background rotation and small depths do promote the two-dimensionality of flows independently, the combination of these two characteristics does not necessarily have that same effect.
Detection and tracking of stem cell state are difficult due to insufficient means for rapidly screening cell state in a noninvasive manner. This challenge is compounded when stem cells are cultured in aggregates or three-dimensional (3D) constructs because living cells in this form are difficult to analyze without disrupting cellular contacts. Multiphoton laser scanning microscopy is uniquely suited to analyze 3D structures due to the broad tunability of excitation sources, deep sectioning capacity, and minimal phototoxicity but is throughput limited. A novel multiphoton fluorescence excitation flow cytometry (MPFC) instrument could be used to accurately probe cells in the interior of multicell aggregates or tissue constructs in an enhanced-throughput manner and measure corresponding fluorescent properties. By exciting endogenous fluorophores as intrinsic biomarkers or exciting extrinsic reporter molecules, the properties of cells in aggregates can be understood while the viable cellular aggregates are maintained. Here we introduce a first generation MPFC system and show appropriate speed and accuracy of image capture and measured fluorescence intensity, including intrinsic fluorescence intensity. Thus, this novel instrument enables rapid characterization of stem cells and corresponding aggregates in a noninvasive manner and could dramatically transform how stem cells are studied in the laboratory and utilized in the clinic.
There is a lack of rigour in the usual explanation for the scaling of the vertical velocity of shallow flows based on geometrical arguments and the continuity equation. In this paper we show, by studying shallow axisymmetric swirl flows, that the dynamics of the flow are crucial to determine the proper scaling. In addition, we present two characteristic scaling parameters for such flows: Reδ2 for the radial velocity and Reδ3 for the vertical velocity, where Re is the Reynolds number of the swirl flow and δ=H/L is the flow aspect ratio with H the fluid depth and L a typical horizontal length scale. This scaling contradicts the common assumption that the vertical velocity should scale with the primary motion proportional to the aspect ratio δ. Moreover, if this scaling applies, then the primary flow can be considered as quasi-two-dimensional. Numerical simulations of a decaying Lamb–Oseen vortex served to test the analytical results and to determine their range of validity. It was found that the primary flow can be considered as quasi-two-dimensional only if δRe1/2≲3 and δRe1/3≲1.
Bleeding after cardiac surgery correlates with morbidity and mortality. The aim of this study was to determine the influence of antiplatelet therapy on bleeding and transfusion rates in coronary artery bypass grafting.
Forty patients receiving aspirin and/or clopidogrel/ticlopidine within 7 days prior to surgery were retrospectively compared to 40 control patients lacking antiplatelet therapy for at least 8 preoperative days. Blood loss was assessed as chest-tube drainage during the first 12 h after surgery. Units transfused were recorded intraoperatively and during stay in the intensive care unit.
Both groups were comparable for pre- and intraoperative data. Irrespective of single or combined antiplatelet therapy, treated patients demonstrated lower fractions of the creatine-kinase isoenzyme MB (5.8 ± 3.1 vs. 8.2 ± 4.1%; P = 0.004) and infarction rates (0 vs. 3; P = 0.240) than control patients, but had significantly more haemorrhages (940 ± 861 mL vs. 412 ± 590 mL; P = 0.002) and transfusion requirements (red cells: 4.5 ± 4.9 vs. 1.5 ± 2.3, plasma: 4.9 ± 6.4 vs. 1.3 ± 2.5, platelets: 1.5 ± 1.3 vs. 0.1 ± 0.2; all P ⩽ 0.001). The differences to control patients were more pronounced for only short antiplatelet therapy free intervals or ongoing antiplatelet therapy (P⩽2 days ⩽ 0.019). For antiplatelet therapy free intervals longer than 2 days, bleeding and transfusion rates (except for platelets) were nonsignificantly higher as compared to control patients (P ⩾ 0.058).
To overcome increased blood loss and transfusion rates, antiplatelet therapy should be discontinued for at least 2 days before elective coronary surgery. Whether patients at high risk for myocardial infarction might benefit from ongoing antiplatelet therapy remains to be investigated.
The effect of Raman instabilities on the production of fast electrons in laser–plasma interaction has been investigated for laser intensities well above the electron trapping threshold. The results of one-dimensional particle-in-cell simulations show that in this regime the presence of Raman backscattering (RBS) hampers fast-electron production, and that its suppression increases the yield of high-energy electrons ($>$15 MeV). Such suppression has been realized either through deletion of all backscattered radiation from the simulations or through direct stimulation of Raman forward scattering (RFS). An increased high-energy electron yield has been observed for both methods. In addition, the influence of various laser and plasma parameters on the production of highly energetic electrons has been investigated. Specifically, the effects of plasma density ramps, skews in the temporal envelopes of the laser pulses, and laser frequency chirp (both pulse-length preserving and bandwidth preserving) have been examined. For each parameter, its influence on the yield of high-energy electrons can be explained from the way it affects the balance between RBS and RFS excitation in laser–plasma interaction.
The benefit of screening healthcare workers (HCWs) at risk for methicillin-resistant Staphylococcus aureus (MRSA) carriage and furloughing MRSA-positive HCWs to prevent spread to patients is controversial. We evaluated our MRSA program for HCWs between 1992 and 2002.
A university medical center in the Netherlands, where methicillin resistance has been kept below 0.5% of all nosocomial S. aureus infections using active surveillance cultures and isolation of colonized patients.
HCWs caring for MRSA-positive patients or patients in foreign hospitals were screened for MRSA. MRSA-positive HCWs had additional cultures, temporary exclusion from patient-related work, assessment of risk factors for persisting carriage, decolonization therapy with mupirocin intranasally and chlorhexidine baths for skin and hair, and follow-up cultures.
Fifty-nine HCWs were colonized with MRSA. Seven of 840 screened employees contracted MRSA in foreign hospitals; 36 acquired MRSA after contact with MRSA-positive patients despite isolation precautions (attack rate per outbreak varied from less than 1% to 15%). Our hospital experienced 17 MRSA outbreaks, including 13 episodes in which HCWs were involved. HCWs were index cases of at least 4 outbreaks. In 8 outbreaks, HCWs acquired MRSA after caring for MRSA-positive patients despite isolation precautions.
Postexposure screening of HCWs allowed early detection of MRSA carriage and prevention of subsequent transmission to patients. Where the MRSA prevalence is higher, the role of HCWs may be greater. In such settings, an adapted version of our program could help prevent dissemination.
To determine incidence rates of hospital-acquired infections and to develop preventive measures to reduce the risk of hospital-acquired infections.
Prospective surveillance for hospital-acquired infections was performed during a 5-year period in the wards housing general and vascular, thoracic, orthopedic, and general gynecologic and gynecologic-oncologic surgery of the University Medical Center Utrecht, the Netherlands. Data were collected from patients with and without infections, using criteria of the Centers for Disease Control and Prevention.
The infection control team recorded 648 hospital-acquired infections affecting 550 (14%) of 3,845 patients. The incidence density was 17.8 per 1,000 patient-days. Patients with hospital-acquired infections were hospitalized for 19.8 days versus 7.7 days for patients without hospital-acquired infections.
Prolongation of stay among patients with hospital-acquired infections may have resulted in 664 fewer admissions due to unavailable beds. Different specialties were associated with different infection rates at different sites, requiring a tailor-made approach. Interventions were recommended for respiratory tract infections in the thoracic surgery ward and for surgical-site infections in the orthopedic and gynecologic surgery wards.
Surveillance in four surgical wards showed that each had its own prominent infection, risk factors, and indications for specific recommendations. Because prospective surveillance requires extensive resources, we considered a modified approach based on a half-yearly point-prevalence survey of hospital-acquired infections in all wards of our hospital. Such surveillance can be extended with procedure-specific prospective surveillance when indicated.
Ten transmission trials with Actinobacillus pleuropneumoniae were carried out. The observed transmission was highly variable, which was surprising since the design of the trials was very similar. We investigated whether the variable transmission could be explained by variation in infectivity of A. pleuropneumoniae infected pigs. We looked for measurable characteristics, which could be indicative for infectious pigs or for the level of infectivity. The characteristic that appeared to be most indicative for a pig being infectious was an A. pleuropneumoniae positive tonsil at necropsy. The characteristic that was correlated to the level of infectivity was the number of A. pleuropneumoniae colonies isolated from the nasal swab, i.e. the probability for an infectious pig to infect a susceptible pig was tenfold higher on days where at least ten colonies were isolated. In this study it is shown that it is possible to measure the bacterial transmission of A. pleuropneumoniae under controlled circumstances if variation in infectivity is taken into account.
Background and objective: We assessed the analgesic efficacy of postoperative epidural infusions of ropivacaine 0.1 and 0.2% combined with sufentanil 1 μg mL−1 in a prospective, randomized, double-blinded study.
Methods: Twenty-two ASA I—III patients undergoing elective total-knee replacement were included. Lumbar epidural blockade using ropivacaine 0.75% was combined with either propofol sedation or general anaesthesia for surgery. After surgery, the epidural infusion was commenced. Eleven patients in each group received either an epidural infusion of ropivacaine 0.1% with 1 μg mL−1 sufentanil (Group 1) or ropivacaine 0.2% with 1 μg mL−1 sufentanil (Group 2) at a rate of 5–9 mL h−1. All patients had access to intravenous pirinatrimide (piritramide) via a patient-controlled analgesia (PCA) device.
Results: Motor block was negligible for the study duration in both groups. There was no significant difference with the 100 mm visual analogue scale (VAS) scores, with the consumption of rescue analgesia or with patient satisfaction. Patients in Group 1 experienced significantly less nausea (P < 0.05) than those in Group 2. Both treatment regimens provided effective postoperative analgesia with only a minimal use of supplemental opioid PCA.
Conclusions: We recommend the use of ropivacaine 0.1% with 1 μg mL−1 sufentanil for postoperative analgesia after total knee replacement as it provides efficient pain relief with no motor block of the lower limbs. In addition, compared with 0.2% ropivacaine with sufentanil, the mixture reduces local anaesthetic consumption without compromise in patient satisfaction or VAS scores. Patients even experience less nausea.
Making use of the polar nature of III-nitride heterostructures, a new FET device concept is proposed. The structure contains an InGaN QW channel sandwiched in between two GaN barrier layers. The charge inthis structure is mainly generated by the strain field in the InGaN layer and is an electron/hole dipole sheet charge located at the opposite InGaN/GaN interfaces. To obtain nchannel characteristics the hole charge at the rear interface (for Ga-face oriented material) is compensated by donor doping of the channel or by modulation doping from the real GaN barrier layer. Growth, processing technology and characteristics of first fabricated devices is discussed.
Several isolates of the entomopathogenic Metarhizium anisopliae that harboured dsRNA viruses of similar electrophoretic band sizes
(1.8 and 2.0 kbp) were assessed for homologies of the dsRNA by Northern analysis. The isolates were also characterised genetically
by RAPD and VCG. Similarly sized dsRNA, as visualised by electrophoresis, were not always homologous, suggesting that the
comparison of dsRNA based solely on electrophoretic banding patterns is an unreliable method of dsRNA characterisation. Several
isolates, but not all, harbouring multiple dsRNA patterns, including a 1.8 and 2.0 kbp doublet, also showed homologies to strains
harbouring only the dsRNA banding doublet. This suggests that mixed infections of different dsRNA elements are found in M.
anisopliae. Genetically similar fungi, based on RAPD banding patterns and vegetative compatibility, were more likely to harbour
genetically related dsRNA. The findings suggested that dsRNA elements in M. anisopliae are horizontally transferred to genetically
related isolates or are maintained through clonal lineages.