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Vertical drift chambers for the Hall A high-resolution spectrometers at Jefferson Lab

The High-Resolution Spectrometers in Hall A at Jefferson Laboratory have been instrumented with state-of-the-art Vertical Drift Chambers designed and constructed by the Nuclear Interactions Group at MITLNS in conjunction with the Physics Division at Jefferson Lab. These chambers rely on a unique, high cell-density design made possible by the absence of field-shaping wires. Each chamber has an inhe

Observation of Exclusive Deeply Virtual Compton Scattering in Polarized Electron Beam Asymmetry Measurements

We report the first results of the beam-spin asymmetry measured in the reaction →ep→epγ at a beam energy of 4.25 GeV. A large asymmetry with a sinφ modulation is observed, as predicted for the interference term of deeply virtual compton scattering (DVCS) and the Bethe-Heitler process. The amplitude of this modulation is α=0.202±0.028. In leading-order and leading-twist perturbative QCD, the α is d

Konstitutionen som politisk arena : Feministers kamp om jämlikhet i det ”nya” Egypten

Det här kapitlet handlar om egyptiska kvinnorättsaktivister och deras arbete med att påverka Egyptens nya konstitution efter revolutionen 2011. Aktivisternas mål var att stärka kvinnors konstitutionella rättigheter och det försökte man nå genom att etablera en arbetsgrupp som på nära håll följde konstitutionsprocessen. I kapitlet analyseras dessa aktivisters kritik av utkasten till konstitutionen

After Image

21 fotografier producerade mellan 2012-2014 som visades i Research Pavilion som en del av Venedig Biennalen 2015. Producenter för utställningen var University of the Arts, Helsingfors

Measurements of the elastic electromagnetic form factor ratio μpGEp/GMp via polarization transfer

We present measurements of the ratio of the proton elastic electromagnetic form factors, μpGEp/GMp. The Jefferson Lab Hall A Focal Plane Polarimeter was used to determine the longitudinal and transverse components of the recoil proton polarization in ep elastic scattering; the ratio of these polarization components is proportional to the ratio of the two form factors. These data reproduce the obse

Exclusive electroproduction of φ mesons at 4.2 GeV

We studied the exclusive reaction e→pe′p′φ using the →φK+K− decay mode. The data were collected using a 4.2 GeV incident electron beam and the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. Our experiment covers the range in Q2 from 0.7 to 2.2 GeV2, and W from 2.0 to 2.6 GeV. Taken together with all previous data, we find a consistent picture of φ

Polarization Measurements in High-Energy Deuteron Photodisintegration

We present measurements of the recoil proton polarization for the d(→γ,→p)n reaction at θc.m.=90° for photon energies up to 2.4 GeV. These are the first data in this reaction for polarization transfer with circularly polarized photons. The induced polarization py vanishes above 1 GeV, contrary to meson-baryon model expectations, in which resonances lead to large polarizations. However, the polariz

The Longitudinal and transverse response of the He-4 (e,e-prime p) reaction in the dip region

A high-resolution study of the (e,e'p) reaction on Helium-4 was carried out at the Institut fuer Kernphysik in Mainz, Germany. The measurements were done in parallel kinematics (momentum transfer q=685 MeV/c, energy transfer omega=334 MeV) at different incident beam energies in order to enable the Rosenbluth separation of the longitudinal and transverse response functions.

The ep→e′pη Reaction at and above the S11(1535) Baryon Resonance

New cross sections for the reaction ep→epη are reported for total center of mass energy W=1.5–1.86GeV and invariant momentum transfer Q2=0.25–1.5(GeV/c)2. This large kinematic range allows extraction of important new information about response functions, photocouplings, and ηN coupling strengths of baryon resonances. Newly observed structure at W∼1.65GeV is shown to come from interference between

The epidemiology of scaphoid fractures in Sweden : a nationwide registry study

The epidemiology of scaphoid fractures has been described in limited populations, and incidence reports have been inconsistent. We investigated the nationwide incidence of scaphoid fractures by evaluating data on 34,377 patients in the Swedish National Patient Register for the years 2006–2015 regarding diagnosis, age, sex and treatment. The data were validated in 300 random patients, and incidence

Combining Depth Fusion and Photometric Stereo for Fine-Detailed 3D Models

In recent years, great progress has been made on the problem of 3D scene reconstruction using depth sensors. On a large scale, these reconstructions look impressive, but often many fine details are lacking due to limitations in the sensor resolution. In this paper we combine two well-known principles for recovery of 3D models, namely fusion of depth images with photometric stereo to enhance the de

Intensional Protocols for Dynamic Epistemic Logic

In dynamical multi-agent systems, agents are controlled by protocols. In choosing a class of formal protocols, an implicit choice is made concerning the types of agents, actions and dynamics representable. This paper investigates one such choice: An intensional protocol class for agent control in dynamic epistemic logic (DEL), called ‘DEL dynamical systems’. After illustrating how such protocols m

A programmable 16-lane SIMD ASIP for massive MIMO

This paper presents a 16-lane, 16-bit complex application-specific instruction processor (ASIP) for baseband processing in massive multiple-input multiple-output (MIMO). The architecture utilizes a 3/4-way very large instruction word (VLIW) with highly efficient pre- and post-processing units specifically trimmed for massive MIMO requirements. Architecture optimizations include features like singl

Contribution of volatiles to the antifungal effect of Lactobacillus paracasei in defined medium and yogurt

Lactic acid bacteria with antifungal properties can be used to control spoilage of food and feed. Previously, most of the identified metabolites have been isolated from cell-free fermentate of lactic acid bacteria with methods suboptimal for detecting possible contribution from volatiles to the antifungal activity. The role of volatile compounds in the antifungal activity of Lactobacillus paracase

Cleaning up NMR spectra with reference deconvolution for improving multivariate analysis of complex mixture spectra

NMR spectroscopy provides valuable data for metabolomics, but the information sought can be partly obscured by errors from hardware imperfection, causing frequency, phase, and spectral lineshape to change significantly between measurements. Clearly, this is a highly undesirable source of variation in multivariate quantitative studies such as metabolomics. Fortunately, many hardware imperfections

Toward Reliable Lipoprotein Particle Predictions from NMR Spectra of Human Blood : An Interlaboratory Ring Test

Lipoprotein profiling of human blood by 1H nuclear magnetic resonance (NMR) spectroscopy is a rapid and promising approach to monitor health and disease states in medicine and nutrition. However, lack of standardization of measurement protocols has prevented the use of NMR-based lipoprotein profiling in metastudies. In this study, a standardized NMR measurement protocol was applied in a ring test

A VLSI Implementation of Angular-Domain Massive MIMO Detection

This paper presents an angular-domain massive MIMO detector which exploits sparsity in massive MIMO channel along with a reconfigurable systolic array architecture to achieve high area efficiency. The underlying idea is to perform signal detection in the angular domain, where the channel matrix can have much lower dimension due the limited number of dominant angles (of arrival and departure) of th