1,030 research outputs found
Adverse drug reactions in hospitalized children in Germany are decreasing: results of a nine year cohort-based comparison
published_or_final_versio
Experimental Indicators of Accretion Processes in Active Galactic Nuclei
Bright Active Galactic Nuclei are powered by accretion of mass onto the super
massive black holes at the centers of the host galaxies. For fainter objects
star formation may significantly contribute to the luminosity. We summarize
experimental indicators of the accretion processes in Active Galactic Nuclei
(AGN), i.e., observable activity indicators that allow us to conclude on the
nature of accretion. The Galactic Center is the closest galactic nucleus that
can be studied with unprecedented angular resolution and sensitivity.
Therefore, here we also include the presentation of recent observational
results on Sagittarius A* and the conditions for star formation in the central
stellar cluster. We cover results across the electromagnetic spectrum and find
that the Sagittarius A* (SgrA*) system is well ordered with respect to its
geometrical orientation and its emission processes of which we assume to
reflect the accretion process onto the super massive black hole.Comment: 16 pages, 4 figures, conference proceeding: Accretion Processes in
Cosmic Sources - APCS2016 - 5-10 September 2016, Saint Petersburg, Russi
The application of predictive modelling for determining bio-environmental factors affecting the distribution of blackflies (Diptera: Simuliidae) in the Gilgel Gibe watershed in Southwest Ethiopia
Blackflies are important macroinvertebrate groups from a public health as well as ecological point of view. Determining the biological and environmental factors favouring or inhibiting the existence of blackflies could facilitate biomonitoring of rivers as well as control of disease vectors. The combined use of different predictive modelling techniques is known to improve identification of presence/absence and abundance of taxa in a given habitat. This approach enables better identification of the suitable habitat conditions or environmental constraints of a given taxon. Simuliidae larvae are important biological indicators as they are abundant in tropical aquatic ecosystems. Some of the blackfly groups are also important disease vectors in poor tropical countries. Our investigations aim to establish a combination of models able to identify the environmental factors and macroinvertebrate organisms that are favourable or inhibiting blackfly larvae existence in aquatic ecosystems. The models developed using macroinvertebrate predictors showed better performance than those based on environmental predictors. The identified environmental and macroinvertebrate parameters can be used to determine the distribution of blackflies, which in turn can help control river blindness in endemic tropical places. Through a combination of modelling techniques, a reliable method has been developed that explains environmental and biological relationships with the target organism, and, thus, can serve as a decision support tool for ecological management strategies
The impact of Stieltjes' work on continued fractions and orthogonal polynomials
Stieltjes' work on continued fractions and the orthogonal polynomials related
to continued fraction expansions is summarized and an attempt is made to
describe the influence of Stieltjes' ideas and work in research done after his
death, with an emphasis on the theory of orthogonal polynomials
The feasibility of using dose-banded syringes to improve the safety and availability of patient-controlled opioid analgesic infusions in children
Current practice of preparing morphine infusions for nurse/patient-controlled analgesia in a UK paediatric hospital: healthcare professionals' views and experiences
Objective To explore the views and experiences of healthcare professionals (HCPs) regarding the preparation of morphine infusions for nurse/patient-controlled analgesia (N/PCA). Methods Three focus groups were conducted with HCPs (anaesthetists, nurses in theatres and wards) at one UK children's hospital. Focus groups were transcribed verbatim and content analysis was used to identify themes. Results A variety of approaches are used to prepare morphine infusions. A lack of appreciation of the excess volume present in morphine ampoules that nominally contain 1 or 2 mL was identified. Other sources of error were miscalculation, complexity of the multistep procedure, distractions and time pressure. Participants suggested that ‘ready-to-use’ prefilled syringes and preprogrammed syringe pumps would improve practice and minimise the risk of error. Conclusions Risks associated with the preparation of infusions for paediatric N/PCA, in particular non-appreciation of the overage (excess volume) in morphine ampoules, raise concerns about the accuracy of current practices
Dual-Beam Actuation of Piezoelectric AlN RF MEMS Switches Monolithically Integrated with AlN Contour-Mode Resonators
This work reports on piezoelectric Aluminum Nitride (AlN) based dual-beam RF MEMS switches that have been monolithically integrated with AlN contour-mode resonators. The dual-beam switch design presented in this paper intrinsically compensates for the residual stress in the deposited films, requires low actuation voltage (5 to 20 V), facilitates active pull-off to open the switch and exhibits fast switching times (1 to 2 μs). This work also presents the combined response (cascaded S parameters) of a resonator and a switch that were co-fabricated on the same substrate. The response shows that the resonator can be effectively turned on and off by the switch. A post-CMOS compatible process was used for the co-fabrication of both the switches and the resonators. The single-chip RF solution presented herein constitutes an unprecedented step forward towards the realization of compact, low loss and integrated multi-frequency RF front-ends
Hybrid Ultra-Compact 4th Order Band-Pass Filters Based On Piezoelectric AlN Contour-Mode MEMS Resonators
This work reports on the design, fabrication and testing of a new class of hybrid (filter design using combined electrical and mechanical coupling techniques) ultra-compact (800×120 μm) 4th order band-pass filters based on piezoelectric Aluminum Nitride (AlN) contour-mode microelectromechanical (MEM) resonators. The demonstrated 110 MHz filter shows a low insertion loss of 5.2 dB in air, a high out-of-band rejection of 65 dB, a fractional bandwidth as high as 1.14% (hard to obtain when only conventional electrical coupling is used in the AlN contour-mode technology), and unprecedented 30 dB and 50 dB shape factors of 1.93 and 2.36, respectively. All these are achieved in an extremely small footprint and by using just half the space that any other 4th order filter would have taken. In terms of nonlinearities, the 110 MHz filter shows a 1 dB compression point higher than +63 dBmV and input third order intercept point (IIP3) values well beyond +153 dBmV. This new hybrid design represents a net improvement over the state of the art and constitutes a very promising solution for intermediate frequency (IF) filtering in many wireless communication systems
Methotrexate-mediated activation of an AMPK-CREB-dependent pathway: a novel mechanism for vascular protection in chronic systemic inflammation
Aims Premature cardiovascular events complicate chronic inflammatory conditions. Low-dose weekly methotrexate (MTX), the most widely used disease-modifying drug for rheumatoid arthritis (RA), reduces disease-associated cardiovascular mortality. MTX increases intracellular accumulation of adenosine monophosphate (AMP) and 5-aminoimidazole-4-carboxamide ribonucleotide which activates AMP-activated protein kinase (AMPK). We hypothesised that MTX specifically protects the vascular endothelium against inflammatory injury via induction of AMPK-regulated protective genes. Methods/results In the (NZW×BXSB)F1 murine model of inflammatory vasculopathy, MTX 1 mg/kg/week significantly reduced intramyocardial vasculopathy and attenuated end-organ damage. Studies of human umbilical vein endothelial cells (HUVEC) and arterial endothelial cells (HAEC) showed that therapeutically relevant concentrations of MTX phosphorylate AMPKαThr172, and induce cytoprotective genes including manganese superoxide dismutase (MnSOD) and haem oxygenase-1 (HO-1). These responses were preserved when HUVECs were pretreated with tumour necrosis factor-α to mimic dysfunctional endothelium. Furthermore, MTX protected against glucose deprivation-induced endothelial apoptosis. Mechanistically, MTX treatment led to cyclic AMP response element-binding protein (CREB)Ser133 phosphorylation, while AMPK depletion attenuated this response and the induction of MnSOD and HO-1. CREB siRNA inhibited upregulation of both cytoprotective genes by MTX, while chromatin immunoprecipitation demonstrated CREB binding to the MnSOD promoter in MTX-treated EC. Likewise, treatment of (NZW×BXSB)F1 mice with MTX enhanced AMPKαThr172 phosphorylation and MnSOD, and reduced aortic intercellular adhesion molecule-1 expression. Conclusions These data suggest that MTX therapeutically conditions vascular endothelium via activation of AMPK-CREB. We propose that this mechanism contributes to the protection against cardiovascular events seen in patients with RA treated with MTX
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