Polytropic Behavior of Solar Wind Protons Observed by Parker Solar Probe

A polytropic process describes the transition of a fluid from one state to another through a specific relationship between the fluid density and temperature. The value of the polytropic index that governs this relationship determines the heat transfer and the effective degrees of freedom during the process. In this study, we analyze solar wind proton plasma measurements, obtained by the Faraday cup instrument on-board Parker Solar Probe. We examine the large-scale variations of the proton plasma density and temperature within the inner heliosphere explored by the spacecraft. We also address a polytropic behavior in the density and temperature fluctuations in short-time intervals, which we analyze in order to derive the effective polytropic index of small time-scale processes. The large-scale variations of the solar wind proton density and temperature which are associated with the plasma expansion through the heliosphere, follow a polytropic model with a polytropic index ~5/3. On the other hand, the short time-scale fluctuations which may be associated with turbulence, follow a model with a larger polytropic index. We investigate possible correlations between the polytropic index of short time-scale fluctuations and the plasma speed, plasma beta, and the magnetic field direction. We discuss the scenario of mechanisms including energy transfer or mechanisms that restrict the particle effective degrees of freedom.Comment: 20 pages, 9 figure

Faster magnetic resonance imaging in emergency room patients with right lower quadrant pain and suspected acute appendicitis

Purpose: Emergency Departments (ED) are becoming busier, with a resultant increase in the number of imaging referrals. The purpose of this study was to assess the diagnostic accuracy of an abbreviated two sequence magnetic resonance (MR) protocol for evaluating ED patients with right lower quadrant pain and suspected acute appendicitis, with a view to expediting patient turnaround times and imaging costs. Material and methods: Fifty patients (49 females, one male; mean age 25.4 ± 5.2 years) who underwent ED MR imaging from July 2014 to March 2015 for right lower quadrant pain were retrospectively reviewed. MR abdomen/pelvis was performed on 1.5 T MR obtaining axial T1 gradient echo in/out of phase, transverse fast spin echo T2 with fat sat/motion correction, axial/coronal T2 HASTE (half-Fourier acquisition single-shot turbo spin-echo), and axial DWI (diffusion-weighted imaging) sequences. Images were reviewed by two fellowship-trained radiologists on a five-point confidence scale. Mean acquisition/interpretation times for the standard departmental protocol and the proposed abbreviated MR protocol (comprising T2 HASTE and DWI images) were calculated. Sensitivity, specificity, and diagnostic accuracy for the abbreviated protocol against the full protocol were also calculated. Results: Mean scanning time for abbreviated protocol and standard protocol was calculated to be 21.1 minutes and 40.5 minutes, respectively. Mean interpretation time for abbreviated protocol for reader one and two was 4.1 ± 1.5 minutes and 4.5 ± 1.4 minutes, respectively, and for standard protocol was 8.1 ± 1.8 minutes and 7.1 ± 1.4 minutes, respectively. Sensitivity, specificity, and accuracy for the FAST protocol were calculated to be 100% each for reader one and 75%, 100%, and 94%, respectively, for reader two. Conclusions: The proposed abbreviated MR protocol has comparable diagnostic accuracy in diagnosing ED patients with right lower quadrant pain, with significant reduction in imaging/interpretation times. It thus has the potential to be implemented in ED imaging with significant reduction in patient turnaround times and costs

A theoretical framework for studying worker participation: The psychosocial contract

[Δε διατίθεται περίληψη / no abstract available][Δε διατίθεται περίληψη / no abstract available

Functional neuroimaging Using UWB Impulse Radar: a feasibility study

Microwave imaging is a promising new modality for studying brain function. In the current paper we assess the feasibility of using a single chip implementation of an ultra- wideband impulse radar for developing a portable and low-cost functional neuroimaging device. A numerical model is used to predict the level of attenuation that will occur when detecting a volume of blood in the cerebral cortex. A phantom liquid is made, to study the radar’s performance at different attenuation levels. Although the radar is currently capable of detecting a point reflector in a phantom liquid with submillimeter accuracy and high temporal resolution, object detection at the desired level of attenuation remains a challenge

Testosterone and the tendency to engage in self-employment

Does testosterone increase the tendency to engage in self-employment? The results presented to date have been mixed. Using three different studies, we provide additional evidence on the relationship between testosterone and self-employment. Drawing on a cross-section of 2,146 individuals (1,178 males and 968 females) from the National Health and Nutrition Examination Surveys’ (NHANES’) 2011-2012 sample, and controlling for endogeneity (with red blood cell count, percentage Hematocrit, and zinc supplements intake in the past 30-days as instruments), serum testosterone levels are positively associated with self-employment for males (marginally significant, two-tailed test). As testosterone levels could be affected by social, economic, and biological factors during one’s life course, to draw more robust inferences we assess whether the 2D:4D digit ratio, a marker of prenatal testosterone exposure, influences the likelihood of self-employment. We reviewed a sample of 971 cases (449 males and 525 females) from Understanding Society’s Innovation Panel 6 (IP6), and our results indicate that males (females) with lower 2D:4D ratio in their left hand, or higher prenatal testosterone exposure, have a significantly greater (marginally significant for females) likelihood of self-employment (two-tailed test). Finally, we examine the twin testosterone transfer effect in a sample of opposite-sex and same-sex twins from the National Survey of Midlife Development (MIDUS I) in the Unites States and provide additional support for the marginally significant (two-tailed test) positive association between testosterone and self-employment

The Impact of Turbulent Solar Wind Fluctuations on Solar Orbiter Plasma Proton Measurements

Solar Orbiter will observe the Sun and the inner heliosphere to study the connections between solar activity, coronal structure, and the origin of the solar wind. The plasma instruments on board Solar Orbiter will determine the three-dimensional velocity distribution functions of the plasma ions and electrons with high time resolution. The analysis of these distributions will determine the plasma bulk parameters, such as density, velocity, and temperature. This paper examines the effects of short-time-scale plasma variations on particle measurements and the estimated bulk parameters of the plasma. For the purpose of this study, we simulate the expected observations of solar wind protons, taking into account the performance of the Proton-Alpha Sensor (PAS) on board Solar Orbiter. We particularly examine the effects of Alfv\'enic and slow-mode-like fluctuations, commonly observed in the solar wind on timescales of milliseconds to hours, on the observations. We do this by constructing distribution functions from modeled observations and calculate their statistical moments in order to derive plasma bulk parameters. The comparison between the derived parameters with the known input allows us to estimate the expected accuracy of Solar Orbiter proton measurements in the solar wind under typical conditions. We find that the plasma fluctuations due to these turbulence effects have only minor effects on future SWA-PAS observation

Ethos

Ethos – meaning the characteristic spirit of a culture, era, or community as manifested in its beliefs and aspirations – is a piece that explores Greek music from the 3rd Millennium B.C.E. to the folk tunes and dances of the 16th century C.E. Ethos incorporates multiphonics, quarter tones, ancient tonal systems and folk scales to show the differences and similarities between ancient and folk styles. The piece also features the traditional Greek drum ‘Daouli’ and mimics ancient instruments with those in a traditional orchestra. As the piece develops, ancient musical fragments can be heard thought the orchestra, chiefly in string and woodwind passages. The violin, harp, flute and clarinet depict the kithara, lyre, floyera and aulos, respectively. The ever present increase in tempo drives both virtuosic and drone like characters to develop and transform

MaxSAT Evaluation 2019 - Benchmark: Identifying Security-Critical Cyber-Physical Components in Weighted AND/OR Graphs

This paper presents a MaxSAT benchmark focused on identifying critical nodes in AND/OR graphs. We use AND/OR graphs to model Industrial Control Systems (ICS) as they are able to semantically grasp intricate logical interdependencies among ICS components. However, identifying critical nodes in AND/OR graphs is an NP-complete problem. We address this problem by efficiently transforming the input AND/OR graph-based model into a weighted logical formula that is then used to build and solve a Weighted Partial MaxSAT problem. The benchmark includes 80 cases with AND/OR graphs of different size and composition as well as the optimal cost and solution for each case

A novel c.5308_5311delGAGA mutation in Senataxin in a Cypriot family with an autosomal recessive cerebellar ataxia

<p>Abstract</p> <p>Background</p> <p>Senataxin (chromosome 9q34) was recently identified as the causative gene for an autosomal recessive form of Ataxia (ARCA), termed as Ataxia with Oculomotor Apraxia, type 2 (AOA2) and characterized by generalized incoordination, cerebellar atrophy, peripheral neuropathy, "oculomotor apraxia" and increased alpha-fetoprotein (AFP). Here, we report a novel Senataxin mutation in a Cypriot ARCA family.</p> <p>Methods</p> <p>We studied several Cypriot autosomal recessive cerebellar ataxia (ARCA) families for linkage to known ARCA gene loci. We linked one family (909) to the SETX locus on chromosome 9q34 and screened the proband for mutations by direct sequencing.</p> <p>Results</p> <p>Sequence analysis revealed a novel c.5308_5311delGAGA mutation in exon 11 of the SETX gene. The mutation has not been detected in 204 control chromosomes from the Cypriot population, the remaining Cypriot ARCA families and 37 Cypriot sporadic cerebellar ataxia patients.</p> <p>Conclusion</p> <p>We identified a novel SETX homozygous c.5308_5311delGAGA mutation that co-segregates with ARCA with cerebellar atrophy and raised AFP.</p

A consensus exercise identifying priorities for research into clinical effectiveness among children's orthopaedic surgeons in the United Kingdom

Aims: High-quality clinical research in children’s orthopaedic surgery has lagged behind other surgical subspecialties. This study used a consensus-based approach to identify research priorities for clinical trials in children’s orthopaedics. / Methods: A modified Delphi technique was used, which involved an initial scoping survey, a two-round Delphi process and an expert panel formed of members of the British Society of Children’s Orthopaedic Surgery. The survey was conducted amongst orthopaedic surgeons treating children in the United Kingdom and Ireland. / Results: A total of 86 clinicians contributed to both rounds of the Delphi process, scoring priorities from one (low priority) to five (high priority). Elective topics were ranked higher than those relating to trauma, with the top ten elective research questions scoring higher than the top question for trauma. Ten elective, and five trauma research priorities were identified, with the three highest ranked questions relating to the treatment of slipped capital femoral epiphysis (mean score 4.6/ 5), Perthes’ disease (4.5) and bone infection (4.5). / Conclusion: This consensus-based research agenda will guide surgeons, academics and funders to improve the evidence in children’s orthopaedic surgery and encourage the development of multicentre clinical trials