230 research outputs found
Post-modernism's use and abuse of Nietzsche
I focus on Nietzsche's architectural metaphor of self-construction in arguing for the claim that postmodern readings of Nietzsche misunderstand his various attacks on dogmatic philosophy as paving the way for acceptance of a self characterized by fundamental disunity. Nietzsche's attack on essentialist dogmatic metaphysics is a call to engage in a purposive self-creation under a unifying will, a will that possesses the strength to reinterpret history as a pathway to "the problem that we are". Nietzsche agrees with the postmodernists that unity is not a pre-given, however he would disavow their rejection of unity as a goal. Where the postmodernists celebrate "the death of the subject" Nietzsche rejects this valorization of disunity as a form of Nihilism and prescribes the creation of a genuine unified subjectivity to those few capable of such a goal. Postmodernists are nearer Nietzsche's idea of the Last Man than his idea of the Overman.Articl
Use of double-blind placebo-controlled N-of-1 trials among stimulant-treated youths in The Netherlands: a descriptive study.
Objectives An N-of-1 trial is a double-blind placebo-controlled randomized trial to objectively and systematically evaluate the individual's response. This approach seems extraordinarily suitable for assessing the efficacy of stimulants in the treatment of attention deficit hyperactivity disorder (ADHD). The aim is to examine the use of N-of-1 trials among youths in the Netherlands, the protocols used, and the continuation of stimulant treatment thereafter. Methods Physicians requesting N-of-1 trials with stimulants were interviewed about their rationale and protocol. Prevalence and continuation were investigated by extracting N-of-1 trials among youths <20 years of age from a large pharmacy dispensing database for 2000-2004. Results The main purpose of N-of-1 trials mentioned by physicians was the assessing of individuals' response and dose-finding. Trial length, dosing schedule and efficacy assessment differed per physician. Trials consisted of a maximum of two treatment periods per dose. The annual percentage of youths starting stimulant treatment with an N-of-1 trial fluctuated between 0.6% (3/462) and 3.3% (10/301). No statistical significant difference could be detected between the continuation of stimulant treatment with or without an N-of-1 trial (p=0.71). Conclusions N-of-1 trials with stimulants are infrequently and not optimally used in the Netherlands. The results of N-of-1 protocols described by physicians are of questionable value, due to the small number of treatment periods per dose. More uniformity in the protocols would make it easier to encompass the N-of-1 methodology in physicians' daily practice
Nearby quasar remnants and ultra-high energy cosmic rays
As recently suggested, nearby quasar remnants are plausible sites of
black-hole based compact dynamos that could be capable of accelerating
ultra-high energy cosmic rays (UHECRs). In such a model, UHECRs would originate
at the nuclei of nearby dead quasars, those in which the putative underlying
supermassive black holes are suitably spun-up. Based on galactic optical
luminosity, morphological type, and redshift, we have compiled a small sample
of nearby objects selected to be highly luminous, bulge-dominated galaxies,
likely quasar remnants. The sky coordinates of these galaxies were then
correlated with the arrival directions of cosmic rays detected at energies EeV. An apparently significant correlation appears in our data. This
correlation appears at closer angular scales than those expected when taking
into account the deflection caused by typically assumed IGM or galactic
magnetic fields over a charged particle trajectory. Possible scenarios
producing this effect are discussed, as is the astrophysics of the quasar
remnant candidates. We suggest that quasar remnants be also taken into account
in the forthcoming detailed search for correlations using data from the Auger
Observatory.Comment: 2 figures, 4 tables, 11 pages. Final version to appear in Physical
Review
HI in the Outskirts of Nearby Galaxies
The HI in disk galaxies frequently extends beyond the optical image, and can
trace the dark matter there. I briefly highlight the history of high spatial
resolution HI imaging, the contribution it made to the dark matter problem, and
the current tension between several dynamical methods to break the disk-halo
degeneracy. I then turn to the flaring problem, which could in principle probe
the shape of the dark halo. Instead, however, a lot of attention is now devoted
to understanding the role of gas accretion via galactic fountains. The current
cold dark matter theory has problems on galactic scales, such as
the core-cusp problem, which can be addressed with HI observations of dwarf
galaxies. For a similar range in rotation velocities, galaxies of type Sd have
thin disks, while those of type Im are much thicker. After a few comments on
modified Newtonian dynamics and on irregular galaxies, I close with statistics
on the HI extent of galaxies.Comment: 38 pages, 17 figures, invited review, book chapter in "Outskirts of
Galaxies", Eds. J. H. Knapen, J. C. Lee and A. Gil de Paz, Astrophysics and
Space Science Library, Springer, in pres
DXA-derived hip shape is related to osteoarthritis:findings from in the MrOS cohort
BF conducted this research whilst on a clinical research primer fellowship awarded by the Elizabeth Blackwell Institute, University of Bristol, UK. This study was funded by Arthritis Research UK project grant ref 20244. CG is funded by Arthritis Research UK grant ref 20000. The Osteoporotic Fractures in Men (MrOS) Study is supported by National Institutes of Health funding. The following institutes provide support: the National Institute on Aging (NIA), the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), the National Center for Advancing Translational Sciences (NCATS), and NIH Roadmap for Medical Research under the following grant numbers: R01 AR052000, K24 AR048841, U01 AG027810, U01 AG042124, U01 AG042139, U01 AG042140, U01 AG042143, U01 AG042145, U01 AG042168, U01 AR066160, and UL1 TR000128.Peer reviewedPostprin
Fitting the integrated Spectral Energy Distributions of Galaxies
Fitting the spectral energy distributions (SEDs) of galaxies is an almost
universally used technique that has matured significantly in the last decade.
Model predictions and fitting procedures have improved significantly over this
time, attempting to keep up with the vastly increased volume and quality of
available data. We review here the field of SED fitting, describing the
modelling of ultraviolet to infrared galaxy SEDs, the creation of
multiwavelength data sets, and the methods used to fit model SEDs to observed
galaxy data sets. We touch upon the achievements and challenges in the major
ingredients of SED fitting, with a special emphasis on describing the interplay
between the quality of the available data, the quality of the available models,
and the best fitting technique to use in order to obtain a realistic
measurement as well as realistic uncertainties. We conclude that SED fitting
can be used effectively to derive a range of physical properties of galaxies,
such as redshift, stellar masses, star formation rates, dust masses, and
metallicities, with care taken not to over-interpret the available data. Yet
there still exist many issues such as estimating the age of the oldest stars in
a galaxy, finer details ofdust properties and dust-star geometry, and the
influences of poorly understood, luminous stellar types and phases. The
challenge for the coming years will be to improve both the models and the
observational data sets to resolve these uncertainties. The present review will
be made available on an interactive, moderated web page (sedfitting.org), where
the community can access and change the text. The intention is to expand the
text and keep it up to date over the coming years.Comment: 54 pages, 26 figures, Accepted for publication in Astrophysics &
Space Scienc
Hansenula polymorpha Swi1p and Snf2p are essential for methanol utilisation
We have cloned the Hansenula polymorpha SWI1 and SNF2 genes by functional complementation of mutants that are defective in methanol utilisation. These genes encode proteins similar to Saccharomyces cerevisiae Swi1p and Snf2p, which are subunits of the SWI/SNF complex. This complex belongs to the family of nucleosome-remodeling complexes that play a role in transcriptional control of gene expression.
Analysis of the phenotypes of constructed H. polymorpha SWI1 and SNF2 disruption strains indicated that these genes are not necessary for growth of cells on glucose, sucrose, or various organic nitrogen sources which involve the activity of peroxisomal oxidases. Both disruption strains showed a moderate growth defect on glycerol and ethanol, but were fully blocked in methanol utilisation. In methanol-induced cells of both disruption strains, two peroxisomal enzymes involved in methanol metabolism, alcohol oxidase and dihydroxyacetone synthase, were hardly detectable, whereas in wild-type cells these proteins were present at very high levels. We show that the reduction in alcohol oxidase protein levels in H. polymorpha SWI1 and SNF2 disruption strains is due to strongly reduced expression of the alcohol oxidase gene. The level of Pex5p, the receptor involved in import of alcohol oxidase and dihydroxyacetone synthase into peroxisomes, was also reduced in both disruption strains compared to that in wild-type cells.
Astronomical Distance Determination in the Space Age: Secondary Distance Indicators
The formal division of the distance indicators into primary and secondary leads to difficulties in description of methods which can actually be used in two ways: with, and without the support of the other methods for scaling. Thus instead of concentrating on the scaling requirement we concentrate on all methods of distance determination to extragalactic sources which are designated, at least formally, to use for individual sources. Among those, the Supernovae Ia is clearly the leader due to its enormous success in determination of the expansion rate of the Universe. However, new methods are rapidly developing, and there is also a progress in more traditional methods. We give a general overview of the methods but we mostly concentrate on the most recent developments in each field, and future expectations. © 2018, The Author(s)
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