1,722 research outputs found
Development of supercritical pressure cryogenic storage and supply systems incorporating the radial bumper-discrete shield design Final report
Design of super critical pressure cryogenic storage and supply equipment with radial bumper shiel
Schuivende panelen
Schuivende panelen was de titel van een partijprogramma uit de jaren tachtig. Deze
rede is echter geen politiek manifest. Hoewel een wetenschapper in staat moet zijn
om politiek te bedrijven en de Allergologie als discipline sinds haar oprichting speelbal
geweest is van politieke krachten gaat deze lezing vooral over verschuivingen en
ontwikkelingen in het vakgebied.
rede
In verkorte vorm uitgesproken
ter gelegenheid van het aanvaarden
van het ambt van bijzonder hoogleraar
met als leeropdracht Allergologie
aan het Erasmus MC, faculteit van de
Erasmus Universiteit Rotterdam, op 20 april 200
Positive and negative AIT trials: What makes the difference?
Background: Allergen immunotherapy has proven to be efficacious in allergic rhinitis and asthma. However, results from randomised clinical trials may vary substantially. Clinical trials may unexpectedly fail. The purpose of this review is to discuss the possible factors that may contribute to a successful or unsuccessful study. Methods: Descriptive review exploring the possible causes of negative outcomes in allergen immunotherapy trials. Results: A series of factors may lead to negative results. Among of these are underpowering of the study, low allergen content in tested extracts, insufficient allergen exposure during monitoring and recruitment of inappropriate patients. In addition, the choice of the primary endpoint may be critical. Discussion: A clinical trial aims to evaluate the efficacy of an agent. However, studies with potential effective compounds may fail because of methodical issues. Sometimes, they are the cause of discrepancies between successful phase II and unsuccessful phase III trials. To understand more about failure of studies, investigators and editors should be encouraged to publish negative trials
Comparison of nasal responsiveness to histamine, methacholine and phentolamine in allergic rhinitis patients and controls
In a selected group of rhinitis patients with an IgE‐mediated allergy to house dust mites the nasal response to insufflation of histamine chloride, methacholine and phentolamine was demonstrated to be higher than in a control group. With the methods used histamine chloride was better at discriminating between healthy subjects and patients than methacholine or phentolamine. This discrimination was shown by assessing the severity of reflex‐mediated symptoms such as the number of sneezes and the amount of secretion, and not by differences in nasal airway resistance. Copyrigh
Nasal allergy to avian antigens
This study describes the case of a patient who developed symptoms of rhinoconjunctivitis on exposure to budgerigars and parrots. An IgE‐mediated allergy to budgerigar, parrot and pigeon antigens was demonstrated using both in‐vivo challenge tests (skin and nasal provocation tests) and in‐vitro investigations (radio‐allergo‐sorbent test, histamine release test). The study shows that the development of nasal disease can be associated with allergy to avian antigens. Copyrigh
Start to end simulations of the ERL prototype at Daresbury Laboratory
Daresbury Laboratory is currently building an Energy Recovery Linac Prototype (ERLP) that will serve as a research and development facility for the study of beam dynamics and accelerator technology important to the design and construction of the proposed 4th Generation Light Source (4GLS) project. Two major objectives of the ERLP are the demonstration of energy recovery and of energy recovery from a beam disrupted by an FEL interaction as supplied by an infrared oscillator system. In this paper we present start-to-end simulations of the ERLP including such an FEL interaction. The beam dynamics in the highbrightness injector, which consists of a DC photocathode Gun and a superconducting booster, have been modelled using the particle tracking code ASTRA. After the booster the particles have been tracked with the code elegant. The 3D code GENESIS 1.3 was used to model the FEL interaction with the electron beam at 35 MeV. A brief summary of impedance and wakefield calculations for the whole machine is also given
Compact single-shot electro-optic detection system for THz pulses with femtosecond time resolution at MHz repetition rates
Electro-optical detection has proven to be a valuable technique to study
temporal profiles of THz pulses with pulse durations down to femtoseconds. As
the Coulomb field around a relativistic electron bunch resembles the current
profile, electro-optical detection can be exploited for non-invasive bunch
length measurements at accelerators. We have developed a very compact and
robust electro-optical detection system based on spectral decoding for bunch
length monitoring at the European XFEL with single-shot resolution better than
200~fs. Apart from the GaP crystal and the corresponding laser optics at the
electron beamline, all components are housed in 19\" chassis for rack mount and
remote operation inside the accelerator tunnel. An advanced laser
synchronization scheme based on radio-frequency down-conversion has been
developed for locking a custom-made Yb-fiber laser to the radio-frequency of
the European XFEL accelerator. In order to cope with the high bunch repetition
rate of the superconducting accelerator, a novel linear array detector
(KALYPSO) has been employed for spectral measurements of the Yb-fiber laser
pulses at frame rates of up to 2.26~MHz. In this paper, we describe all
sub-systems of the electro-optical detection system as well as the measurement
procedure in detail, and discuss first measurement results of longitudinal
bunch profiles of around 400~fs (rms) with an arrival-time jitter of 35~fs
(rms)
Geometric representations for minimalist grammars
We reformulate minimalist grammars as partial functions on term algebras for
strings and trees. Using filler/role bindings and tensor product
representations, we construct homomorphisms for these data structures into
geometric vector spaces. We prove that the structure-building functions as well
as simple processors for minimalist languages can be realized by piecewise
linear operators in representation space. We also propose harmony, i.e. the
distance of an intermediate processing step from the final well-formed state in
representation space, as a measure of processing complexity. Finally, we
illustrate our findings by means of two particular arithmetic and fractal
representations.Comment: 43 pages, 4 figure
Intranasal cold dry air is superior to histamine challenge in determining the presence and degree of nasal hyperreactivity in nonallergic noninfectious perennial rhinitis
The objective of the study was to compare cold dry air (CDA) and histamine
in differentiating patients with nonallergic noninfectious perennial
rhinitis (NANIPER) from control subjects. Nasal reactivity (nasal patency,
mucus production, and sneezing) in 16 symptomatic nonsmoking patients with
NANIPER and seven nonsmoking control subjects was measured with
standardized CDA and histamine provocation series in a randomized
crossover study. Intranasal CDA resulted in increased mucus production and
nasal blockage in a dose-dependent manner in patients with NANIPER but not
in control subjects. Sneezing did not occur. The reproducibility of CDA
for patency and mucus production was good. Sen
SAT-based Explicit LTL Reasoning
We present here a new explicit reasoning framework for linear temporal logic
(LTL), which is built on top of propositional satisfiability (SAT) solving. As
a proof-of-concept of this framework, we describe a new LTL satisfiability
tool, Aalta\_v2.0, which is built on top of the MiniSAT SAT solver. We test the
effectiveness of this approach by demonnstrating that Aalta\_v2.0 significantly
outperforms all existing LTL satisfiability solvers. Furthermore, we show that
the framework can be extended from propositional LTL to assertional LTL (where
we allow theory atoms), by replacing MiniSAT with the Z3 SMT solver, and
demonstrating that this can yield an exponential improvement in performance
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