pinecone/core-2020-05-10-deduplication huggingface dataset:
GATE: a simulation toolkit for PET and SPECT

Monte Carlo simulation is an essential tool in emission tomography that can assist in the design of new medical imaging devices, the optimization of acquisition protocols and the development or assessment of image reconstruction algorithms and correction techniques. GATE, the Geant4 Application for Tomographic Emission, encapsulates the Geant4 libraries to achieve a modular, versatile, scripted simulation toolkit adapted to the field of nuclear medicine. In particular, GATE allows the description of time-dependent phenomena such as source or detector movement, and source decay kinetics. This feature makes it possible to simulate time curves under realistic acquisition conditions and to test dynamic reconstruction algorithms. This paper gives a detailed description of the design and development of GATE by the OpenGATE collaboration, whose continuing objective is to improve, document and validate GATE by simulating commercially available imaging systems for PET and SPECT. Large effort is also invested in the ability and the flexibility to model novel detection systems or systems still under design. A public release of GATE licensed under the GNU Lesser General Public License can be downloaded at http:/www-lphe.epfl.ch/GATE/. Two benchmarks developed for PET and SPECT to test the installation of GATE and to serve as a tutorial for the users are presented. Extensive validation of the GATE simulation platform has been started, comparing simulations and measurements on commercially available acquisition systems. References to those results are listed. The future prospects towards the gridification of GATE and its extension to other domains such as dosimetry are also discussed
A light sterile neutrino from Friedberg–Lee symmetry

Light sterile neutrinos of mass about an eV with mixing <math altimg="si1.gif" xmlns="http://www.w3.org/1998/Math/MathML"><msub><mrow><mover accent="true"><mrow><mi>U</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mi>l</mi><mi>s</mi></mrow></msub></math> of a few percent to active neutrinos may solve some anomalies shown in experimental data related to neutrino oscillation. How to have light sterile neutrinos is one of the theoretical problems which have attracted a lot of attentions. In this article we show that such an eV scale light sterile neutrino candidate can be obtained in a seesaw model in which the right-handed neutrinos satisfy a softly-broken Friedberg–Lee (FL) symmetry. In this model a right-handed neutrino is guaranteed by the FL symmetry to be light comparing with other two heavy right-handed neutrinos. It can be of eV scale when the FL symmetry is softly broken and can play the role of eV scale sterile neutrino needed for explaining the anomalies of experimental data. This model predicts that one of the active neutrino is massless. We find that this model prefers inverted hierarchy mass pattern of active neutrinos than normal hierarchy. An interesting consequence of this model is that realizing relatively large <math altimg="si2.gif" xmlns="http://www.w3.org/1998/Math/MathML"><mo stretchy="false">|</mo><msub><mrow><mover accent="true"><mrow><mi>U</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mi>e</mi><mi>s</mi></mrow></msub><mo stretchy="false">|</mo></math> and relatively small <math altimg="si3.gif" xmlns="http://www.w3.org/1998/Math/MathML"><mo stretchy="false">|</mo><msub><mrow><mover accent="true"><mrow><mi>U</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mi>μ</mi><mi>s</mi></mrow></msub><mo stretchy="false">|</mo></math> in this model naturally leads to a relatively small <math altimg="si4.gif" xmlns="http://www.w3.org/1998/Math/MathML"><mo stretchy="false">|</mo><msub><mrow><mover accent="true"><mrow><mi>U</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mi>τ</mi><mi>s</mi></mrow></msub><mo stretchy="false">|</mo></math> . This interesting prediction can be tested in future atmospheric or solar neutrino experiments
Classical conformal blocks and Painlevé VI

We study the classical c → ∞ limit of the Virasoro conformal blocks. We point out that the classical limit of the simplest nontrivial null-vector decoupling equation on a sphere leads to the Painlevé VI equation. This gives the explicit representation of generic four-point classical conformal block in terms of the regularized action evaluated on certain solution of the Painlevé VI equation. As a simple consequence, the monodromy problem of the Heun equation is related to the connection problem for the Painlevé VI
Multiparticle Higgs and vector boson amplitudes at threshold

In a spontaneously broken gauge theory we consider (sub)-processes in which one virtual intermediate state (it can be a Higgs or a gauge field) produces many on-shell Higgses and massive vector bosons. In the kinematic regime where all final states are produced on their mass threshold, we show how to compute iteratively all tree-level amplitudes A 1 → n + m $$ {\mathcal{A}}_{1\to n+ m} $$ involving an arbitrary number n of Higgs bosons and m of longitudinal vector bosons in the final state, and list the amplitudes coefficients for up to n =32 and m =32. Wefindthattheseamplitudesexhibitfactorialgrowthnotonlyinthenumberof scalar fields, but also in the number of longitudinal gauge fields, A 1 → n + m $$ {\mathcal{A}}_{1\to n+ m} $$ ~ n ! m !. This growth is not expected to disappear at loop-level in the fixed-order perturbation theory. We conclude that at energies accessible at the next generation of hadron colliders, such as the 50-100 TeV FCC, where s ^ $$ \sqrt{\widehat{s}} $$ is sufficient to produce ≫1 /α W of W, Z and H , perturbation theory breaks down when applied to the multiparticle electroweak production, at least near the kinematic multiparticle mass threshold where the electroweak gauge-Higgs sector becomes strongly coupled
Measurement of the doubly-polarized He3→(γ→,n)pp reaction at 16.5 MeV and its implications for the GDH sum rule

We report new measurements of the double-polarized photodisintegration of 3 He at an incident photon energy of 16.5 MeV, carried out at the High Intensity γ -ray Source (HI γ S) facility located at Triangle Universities Nuclear Laboratory (TUNL). The spin-dependent double-differential cross sections and the contribution from the three-body channel to the Gerasimov–Drell–Hearn (GDH) integrand were extracted and compared with the state-of-the-art three-body calculations. The calculations, which include the Coulomb interaction and are in good agreement with the results of previous measurements at 12.8 and 14.7 MeV, deviate from the new cross section results at 16.5 MeV. The GDH integrand was found to be about one standard deviation larger than the maximum value predicted by the theories
"These things are dangerous": understanding induced abortion trajectories in urban Zambia

Unsafe abortion is a significant but preventable cause of global maternal mortality and morbidity. Zambia has among the most liberal abortion laws in sub-Saharan Africa, however this alone does not guarantee access to safe abortion, and 30% of maternal mortality is attributable to unsafe procedures. Too little is known about the pathways women take to reach abortion services in such resource-poor settings, or what informs care-seeking behaviours, barriers and delays. In-depth qualitative interviews were conducted in 2013 with 112 women who accessed abortion-related care in a Lusaka tertiary government hospital at some point in their pathway. The sample included women seeking safe abortion and also those receiving hospital care following unsafe abortion. We identified a typology of three care-seeking trajectories that ended in the use of hospital services: clinical abortion induced in hospital; clinical abortion initiated elsewhere, with post-abortion care in hospital; and non-clinical abortion initiated elsewhere, with post-abortion care in hospital. Framework analyses of 70 transcripts showed that trajectories to a termination of an unwanted pregnancy can be complex and iterative. Individuals may navigate private and public formal healthcare systems and consult unqualified providers, often trying multiple strategies. We found four major influences on which trajectory a woman followed, as well as the complexity and timing of her trajectory: i) the advice of trusted others ii) perceptions of risk iii) delays in care-seeking and receipt of services and iv) economic cost. Even though abortion is legal in Zambia, girls and women still take significant risks to terminate unwanted pregnancies. Levels of awareness about the legality of abortion and its provision remain low even in urban Zambia, especially among adolescents. Unofficial payments required by some providers can be a major barrier to safe care. Timely access to safe abortion services depends on chance rather than informed exercise of entitlement
Characterization of the anticipated synchronization regime in the coupled FitzHugh–Nagumo model for neurons

7 pages, 5 figures.-- PACS nrs.: 05.45.Xt; 05.40.Ca; 87.19.Bb.-- Printed version published Jul 1, 2003.-- Contributed to: "Stochastic Systems: From Randomness to Complexity" (Erice, Italy, Jul 26-Aug 1, 2002).ArXiv pre-print available at: http://arxiv.org/abs/cond-mat/0210261We characterize numerically the regime of anticipated synchronization in the coupled FitzHugh–Nagumo model for neurons. We consider two neurons, coupled unidirectionally (in a master–slave configuration), subject to the same random external forcing and with a recurrent inhibitory delayed connection in the slave neuron. We show that the scheme leads to anticipated synchronization, a regime in which the slave neuron fires the same train of pulses as the master neuron, but earlier in time. We characterize the synchronization in the parameter space (coupling strength, anticipation time) and introduce several quantities to measure the degree of synchronization.The work is supported by MCyT (Spain) and FEDER, projects BFM2001-0341-C02-01 and BMF2000-1108. C. Masoller acknowledges partial support from the Universitat de les Illes Balears.Peer reviewe
Second-harmonic generation in highly textured LiNbO3 films prepared by pulsed laser deposition

LiNbO3 films have been deposited on (001) sapphire substrates by pulsed laser deposition, in an oxygen environment. Films grown at substrate temperatures of 650°C are crystalline, strongly textured, and show a degree of twining that is lower the higher the oxygen pressure is in the range of 0.5-1 Torr. Values of the nonlinear optical coefficients d33 and d31 of the films, measured via second-harmonic generation, are close to those for the bulk LiNbO3 single crystal. The dependence of both the degree of twining and the nonlinear optical response on the film thickness suggests that the films become closer to single domain for larger thickness. © 2000 American Institute of Physics.Peer Reviewe
Risk profiles and prognosis of treated and untreated hypertensive men and women in a population-based longitudinal study: the Reykjavik Study

To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldThe aim was to examine the risk profiles and prognosis of treated and untreated hypertensive subjects and examine to what degree confounding by indication was present in a population-based cohort study with up to 30-year follow-up. The study population consisted of 9328 men and 10 062 women, aged 33-87 years at the time of attendance from 1967 to 1996. The main outcome measures were myocardial infarction (MI), cardiovascular disease (CVD) mortality and all-cause mortality. Comparing the risk profiles between treated and untreated subjects entering the study showed significantly higher values for some risk factors for treated subjects. During the first 10 years, hypertensive men without treatment, compared with those treated, had a significantly lower risk of suffering MI, CVD and all-cause mortality, hazard ratio (HR) 0.72 (95% CI; 0.57, 0.90), 0.75 (95% CI; 0.59, 0.95) and 0.81 (95% CI; 0.61, 0.98), respectively. No significant differences in outcome were seen during the following 20 years. In identically defined groups of women, no significant differences in mortality were seen between groups. Subgroup analysis, at two stages of the study 5 years apart, revealed that some cardiovascular risk factors had a higher prevalence in hypertensive men who were treated at the later stage, compared with those who remained untreated (P=0.004). In conclusion, hypertensive treated men had a worse prognosis during the first 10 years of follow-up than untreated ones, which is most likely due to worse baseline risk profile. Hypertensive men that were treated at a later stage had a worse risk profile than those not treated at a later stage
A variant in MCF2L is associated with osteoarthritis.

To access publisher full text version of this article. Please click on the hyperlink in Additional Links field.Osteoarthritis (OA) is a prevalent, heritable degenerative joint disease with a substantial public health impact. We used a 1000-Genomes-Project-based imputation in a genome-wide association scan for osteoarthritis (3177 OA cases and 4894 controls) to detect a previously unidentified risk locus. We discovered a small disease-associated set of variants on chromosome 13. Through large-scale replication, we establish a robust association with SNPs in MCF2L (rs11842874, combined odds ratio [95% confidence interval] 1.17 [1.11-1.23], p = 2.1 × 10(-8)) across a total of 19,041 OA cases and 24,504 controls of European descent. This risk locus represents the third established signal for OA overall. MCF2L regulates a nerve growth factor (NGF), and treatment with a humanized monoclonal antibody against NGF is associated with reduction in pain and improvement in function for knee OA patients
Targeted prostate cancer screening in BRCA1 and BRCA2 mutation carriers: results from the initial screening round of the IMPACT study.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files.\ud
This article is open access.Men with germline breast cancer 1, early onset (BRCA1) or breast cancer 2, early onset (BRCA2) gene mutations have a higher risk of developing prostate cancer (PCa) than noncarriers. IMPACT (Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted screening in BRCA1/2 mutation carriers and controls) is an international consortium of 62 centres in 20 countries evaluating the use of targeted PCa screening in men with BRCA1/2 mutations.To report the first year's screening results for all men at enrollment in the study.We recruited men aged 40-69 yr with germline BRCA1/2 mutations and a control group of men who have tested negative for a pathogenic BRCA1 or BRCA2 mutation known to be present in their families. All men underwent prostate-specific antigen (PSA) testing at enrollment, and those men with PSA >3 ng/ml were offered prostate biopsy.PSA levels, PCa incidence, and tumour characteristics were evaluated. The Fisher exact test was used to compare the number of PCa cases among groups and the differences among disease types.We recruited 2481 men (791 BRCA1 carriers, 531 BRCA1 controls; 731 BRCA2 carriers, 428 BRCA2 controls). A total of 199 men (8%) presented with PSA >3.0 ng/ml, 162 biopsies were performed, and 59 PCas were diagnosed (18 BRCA1 carriers, 10 BRCA1 controls; 24 BRCA2 carriers, 7 BRCA2 controls); 66% of the tumours were classified as intermediate- or high-risk disease. The positive predictive value (PPV) for biopsy using a PSA threshold of 3.0 ng/ml in BRCA2 mutation carriers was 48%-double the PPV reported in population screening studies. A significant difference in detecting intermediate- or high-risk disease was observed in BRCA2 carriers. Ninety-five percent of the men were white, thus the results cannot be generalised to all ethnic groups.The IMPACT screening network will be useful for targeted PCa screening studies in men with germline genetic risk variants as they are discovered. These preliminary results support the use of targeted PSA screening based on BRCA genotype and show that this screening yields a high proportion of aggressive disease.In this report, we demonstrate that germline genetic markers can be used to identify men at higher risk of prostate cancer. Targeting screening at these men resulted in the identification of tumours that were more likely to require treatment
A multipopulation parallel genetic simulated annealing-based QoS routing and wavelength assignment integration algorithm for multicast in optical networks

In this paper, we propose an integrated Quality of Service (QoS) routing algorithm for optical networks. Given a QoS multicast request and the delay interval specified by users, the proposed algorithm can find a flexible-QoS-based cost suboptimal routing tree. The algorithm first constructs the multicast tree based on the multipopulation parallel genetic simulated annealing algorithm, and then assigns wavelengths to the tree based on the wavelength graph. In the algorithm, routing and wavelength assignment are integrated into a single process. For routing, the objective is to find a cost suboptimal multicast tree. For wavelength assignment, the objective is to minimize the delay of the multicast tree, which is achieved by minimizing the number of wavelength conversion. Thus both the cost of multicast tree and the user QoS satisfaction degree can approach the optimal. Our algorithm also considers load balance. Simulation results show that the proposed algorithm is feasible and effective. We also discuss the practical realization mechanisms of the algorithm
Extended phase field higher-order active contour models for networks.

This paper addresses the segmentation from an image of entities that have the form of a ‘network’, i.e. the region in the image corresponding to the entity is composed of branches joining together at junctions, e.g. road or vascular networks. We present new phase field higher-order active contour (HOAC) prior models for network regions, and apply them to the segmentation of road networks from very high resolution satellite images. This is a hard problem for two reasons. First, the images are complex, with much ‘noise’ in the road region due to cars, road markings, etc., while the background is very varied, containing many features that are locally similar to roads. Second, network regions are complex to model, because they may have arbitrary topology. In particular, we address a limitation of a previous model in which network branch width was constrained to be similar to maximum network branch radius of curvature, thereby providing a poor model of networks with straight narrow branches or highly curved, wide branches. We solve this problem by introducing first an additional nonlinear nonlocal HOAC term, and then an additional linear nonlocal HOAC term to improve the computational speed. Both terms allow separate control of branch width and branch curvature, and furnish better prolongation for the same width, but the linear term has several advantages: it is more efficient, and it is able to model multiple widths simultaneously. To cope with the difficulty of parameter selection for these models, we perform a stability analysis of a long bar with a given width, and hence show how to choose the parameters of the energy functions. After adding a likelihood energy, we use both models to extract the road network quasi-automatically from pieces of a QuickBird image, and compare the results to other models in the literature. The state-of-the-art results obtained demonstrate the superiority of our new models, the importance of strong prior knowledge in general, and of the new terms in particular
Data characterizing the chloroplast genomes of extinct and endangered Hawaiian endemic mints (Lamiaceae) and their close relatives.

These data are presented in support of a plastid phylogenomic analysis of the recent radiation of the Hawaiian endemic mints (Lamiaceae), and their close relatives in the genus Stachys, “The quest to resolve recent radiations: Plastid phylogenomics of extinct and endangered Hawaiian endemic mints (Lamiaceae)” [1]. Here we describe the chloroplast genome sequences for 12 mint taxa. Data presented include summaries of gene content and length for these taxa, structural comparison of the mint chloroplast genomes with published sequences from other species in the order Lamiales, and comparisons of variability among three Hawaiian taxa vs. three outgroup taxa. Finally, we provide a list of 108 primer pairs targeting the most variable regions within this group and designed specifically for amplification of DNA extracted from degraded herbarium material
Ellipsoidal plasma mirror focusing of high power laser pulses to ultra-high intensities

The design and development of an ellipsoidal F/1 focusing plasma mirror capable of increasing the peak intensity achievable on petawatt level laser systems to > 10 22 Wcm-2 is presented. A factor of 2.5 reduction in the focal spot size is achieved when compared to F/3 focusing with a conventional (solid state) optic. We find a factor 3.6 enhancement in peak intensity, taking into account changes in plasma mirror reflectivity and focal spot quality. The sensitivity of the focusing plasma optic to misalignment is also investigated. It is demonstrated that an increase in peak laser intensity from 3 x 10 20 Wcm-2 to 10 21 Wcm-3 results in a factor of two increase in the maximum energy of sheath-accelerated protons from a thin foil positioned at the focus of the intense laser light
Multi-pair states in electron-positron pair creation

Ultra strong electromagnetic fields can lead to spontaneous creation of
single or multiple electron-positron pairs. A quantum field theoretical
treatment of the pair creation process combined with numerical methods provides
a description of the fermionic quantum field state, from which all observables
of the multiple electron-positron pairs can be inferred. This allows to study
the complex multi-particle dynamics of electron-positron pair creation
in-depth, including multi-pair statistics as well as momentum distributions and
spin. To illustrate the potential benefit of this approach, it is applied to
the intermediate regime of pair creation between nonperturbative Schwinger pair
creation and perturbative multiphoton pair creation where the creation of
multi-pair states becomes nonnegligible but cascades do not yet set in.
Furthermore, it is demonstrated how spin and helicity of the created electrons
and positrons are affected by the polarization of the counterpropagating laser
fields, which induce the creation of electron-positron pairs
Impact of the first-forbidden $\beta$ decay on the production of $A \sim
  195$ r-process peak

We investigated the effects of first-forbidden transitions in $\beta$ decays
on the production of the r-process $A \sim 195$ peak. The theoretical
calculated $\beta$-decay rates with $\beta$-delayed neutron emission were
examined using several astrophysical conditions. As the first-borbidden decay
is dominant in $N \sim 126$ neutron-rich nuclei, their inclusion shortens
$\beta$-decay lifetimes and shifts the abundance peak towards higher masses.
Additionally, the inclusion of the $\beta$-delayed neutron emission results in
a wider abundance peak, and smoothens the mass distribution by removing the
odd-even mass staggering. The effects are commonly seen in the results of all
adopted astrophysical models. Nevertheless there are quantitative differences,
indicating that remaining uncertainty in the determination of half-lives for
$N=126$ nuclei is still significant in order to determine the production of the
r-process peak.Comment: 6 pages, 4 figures, 1 table, Phys. Lett. B, in pres