53 research outputs found
A data compression and optimal galaxy weights scheme for Dark Energy Spectroscopic Instrument and weak lensing datasets
Combining different observational probes, such as galaxy clustering and weak
lensing, is a promising technique for unveiling the physics of the Universe
with upcoming dark energy experiments. The galaxy redshift sample from the Dark
Energy Spectroscopic Instrument (DESI) will have a significant overlap with
major ongoing imaging surveys specifically designed for weak lensing
measurements: the Kilo-Degree Survey (KiDS), the Dark Energy Survey (DES) and
the Hyper Suprime-Cam (HSC) survey. In this work we analyse simulated redshift
and lensing catalogues to establish a new strategy for combining high-quality
cosmological imaging and spectroscopic data, in view of the first-year data
assembly analysis of DESI. In a test case fitting for a reduced parameter set,
we employ an optimal data compression scheme able to identify those aspects of
the data that are most sensitive to the cosmological information, and amplify
them with respect to other aspects of the data. We find this optimal
compression approach is able to preserve all the information related to the
growth of structure; we also extend this scheme to derive weights to be applied
to individual galaxies, and show that these produce near-optimal results.Comment: 14 pages, 12 Figures, DESI collaboration articl
From ‘shallow’ to ‘deep’ policing:‘crash-for-cash’ insurance fraud investigation in England and Wales and the need for greater regulation
The policing of insurance fraud has traditionally been dealt with beyond the criminal justice system as a private matter between the claimant and the insurer with only a few iconic cases referred to the criminal justice system each year. The growth of insurance fraud, particularly ‘crash-for-cash’ fraud, and the disinterest of the police, has led to a change in the response of the insurance industry. This paper will argue that this response can be characterised as a shift from the traditional ‘shallow’ to a ‘deeper’ form of policing which sees greater focus upon criminal and quasi-criminal outcomes. This paper explores some of the private and innovative methods the industry has developed and illustrates what greater private criminal investigation might look like at a time when police privatisation has become a higher profile issue. The paper argues the shift to ‘deeper’ policing necessitates greater regulation of the private investigation of crime and outlines a number of proposals to address this gap which require further consideration and debate
Importance of rostral ventrolateral medulla neurons in determining efferent sympathetic nerve activity and blood pressure
Accentuated sympathetic nerve activity (SNA) is a risk factor for cardiovascular events. In this review, we investigate our working hypothesis that potentiated activity of neurons in the rostral ventrolateral medulla (RVLM) is the primary cause of experimental and essential hypertension. Over the past decade, we have examined how RVLM neurons regulate peripheral SNA, how the sympathetic and renin-angiotensin systems are correlated and how the sympathetic system can be suppressed to prevent cardiovascular events in patients. Based on results of whole-cell patch-clamp studies, we report that angiotensin II (Ang II) potentiated the activity of RVLM neurons, a sympathetic nervous center, whereas Ang II receptor blocker (ARB) reduced RVLM activities. Our optical imaging demonstrated that a longitudinal rostrocaudal column, including the RVLM and the caudal end of ventrolateral medulla, acts as a sympathetic center. By organizing and analyzing these data, we hope to develop therapies for reducing SNA in our patients. Recently, 2-year depressor effects were obtained by a single procedure of renal nerve ablation in patients with essential hypertension. The ablation injured not only the efferent renal sympathetic nerves but also the afferent renal nerves and led to reduced activities of the hypothalamus, RVLM neurons and efferent systemic sympathetic nerves. These clinical results stress the importance of the RVLM neurons in blood pressure regulation. We expect renal nerve ablation to be an effective treatment for congestive heart failure and chronic kidney disease, such as diabetic nephropathy
From ‘shallow’ to ‘deep’ policing: ‘crash-for-cash’ insurance fraud investigation in England and Wales and the need for greater regulation
The policing of insurance fraud has traditionally been dealt with beyond the criminal justice system as a private matter between the claimant and the insurer with only a few iconic cases referred to the criminal justice system each year. The growth of insurance fraud, particularly ‘crash-for-cash’ fraud, and the disinterest of the police, has led to a change in the response of the insurance industry. This paper will argue that this response can be characterised as a shift from the traditional ‘shallow’ to a ‘deeper’ form of policing which sees greater focus upon criminal and quasi-criminal outcomes. This paper explores some of the private and innovative methods the industry has developed and illustrates what greater private criminal investigation might look like at a time when police privatisation has become a higher profile issue. The paper argues the shift to ‘deeper’ policing necessitates greater regulation of the private investigation of crime and outlines a number of proposals to address this gap which require further consideration and debate
Search for Gravitational Waves from Intermediate Mass Binary Black Holes
We present the results of a weakly modeled burst search for gravitational
waves from mergers of non-spinning intermediate mass black holes (IMBH) in the
total mass range 100--450 solar masses and with the component mass ratios
between 1:1 and 4:1. The search was conducted on data collected by the LIGO and
Virgo detectors between November of 2005 and October of 2007. No plausible
signals were observed by the search which constrains the astrophysical rates of
the IMBH mergers as a function of the component masses. In the most efficiently
detected bin centered on 88+88 solar masses, for non-spinning sources, the rate
density upper limit is 0.13 per Mpc^3 per Myr at the 90% confidence level.Comment: 13 pages, 4 figures: data for plots and archived public version at
https://dcc.ligo.org/cgi-bin/DocDB/ShowDocument?docid=62326, see also the
public announcement at http://www.ligo.org/science/Publication-S5IMBH
An embedding technique to determine ττ backgrounds in proton-proton collision data
An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe
Exclusive photoproduction of pi degrees up to large values of Mandelstam variables s, t, and u with CLAS
Exclusive photoproduction cross sections have been measured for the process
with the Dalitz decay final state
using tagged photon energies in the range of GeV.
The complete angular distribution of the final state , for the entire
photon energy range up to large values of and , has been measured for
the first time. The data obtained show that the cross section , at
mid to large angles, decreases with energy as . This is in
agreement with the perturbative QCD quark counting rule prediction of . Paradoxically, the size of angular distribution of measured cross sections
is greatly underestimated by the QCD based Generalized Parton Distribution
mechanism at highest available invariant energy GeV. At the same
time, the Regge exchange based models for photoproduction are more
consistent with experimental data.Comment: 7 pages, 6 figure
Performance of missing transverse momentum reconstruction in proton-proton collisions at root s=13 TeV using the CMS detector
The performance of missing transverse momentum ((p) over right arrow (miss)(T)) reconstruction algorithms for the CMS experiment is presented, using proton-proton collisions at a center-of-mass energy of 13 TeV, collected at the CERN LHC in 2016. The data sample corresponds to an integrated luminosity of 35.9 fb(-1). The results include measurements of the scale and resolution of (p) over right arrow (miss)(T), and detailed studies of events identified with anomalous (p) over right arrow (miss)(T). The performance is presented of a (p) over right arrow (miss)(T) reconstruction algorithm that mitigates the effects of multiple proton-proton interactions, using the "pileup per particle identification" method. The performance is shown of an algorithm used to estimate the compatibility of the reconstructed (p) over right arrow (miss)(T) with the hypothesis that it originates from resolution effects.Peer reviewe
Ten Years of Cooperative Helicopter Aeroacoustics Research in the DNW.
Both the main rotor and the tail rotor of a helicopter generate noise as individual sources. They also interact aerodynamically, causing "interaction noise". Since there is no uniform inflow into the rotor, an individual rotor blade is subjected to widely differing flow conditions. To make the helicopter an environmentally acceptable aircraft, it must be quiet. It is, therfore, the task of the scientist and the research engineer to further the understanding of the mechanisms of noise generation of helicopter rotor, to develop means of controlling these mechanisms towards less noise generation, and to provide the helicopter manufacturer and the operator with guidance on how to build and fly an acoustically "non-intrusive" aircraft. The German Dutch Wind Tunnel (DNW) meets most of these stringent qualifications for conducting high quality aeroacoustic rotor system tests. In this paper some of the more outstanding research projects that were conducted in the DNW by the staffs of the DLR, of the NASA-Langley Research Center and of the US-Army, frequently cooperative and within the framework of "Memoranda of Understanding" or of "Letters of Agreement" are discussed
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