pinecone/core-2020-05-10-deduplication huggingface dataset:
The ion beam shepherd: A new concept for asteroid deflection

A novel slow push asteroid deflection strategy has been recently proposed in which an Earth threatening asteroid can be deflected by exploiting the momentum transmitted by a collimated beam of quasi-neutral plasma impinging against the asteroid surface. The beam can be generated with state-of-the art ion engines from a hovering spacecraft with no need for physical attachment or gravitational interaction with the celestial body. The spacecraft, placed at a distance of a few asteroid diameters, would need an ion thruster pointed at the asteroid surface as well as a second propulsion system to compensate for the ion engine reaction and keep the distance between the asteroid and the shepherd satellite constant throughout the deflection phase. A comparison in terms of required spacecraft mass per total imparted deflection impulse shows that the method outperforms the gravity tractor concept by more than one order of magnitude for asteroids up to about 200 m diameter. The two methods would yield comparable performance for asteroids larger than about 2 k
Ionization energies of amphoteric-doped Cu2ZnSnS4: Photovoltaic application

The substitution of Cu, Sn or Zn in the quaternary Cu2ZnSnS4 semiconductor by impurities that introduce intermediate states in the energy bandgap could have important implications either for photovoltaic or spintronic applications. This allows more generation–recombination channels than for the host semiconductor. We explore and discuss this possibility by obtaining the ionization energies from total energy first-principles calculations. The three substitutions of Cu, Sn and Zn by impurities are analyzed. From these results we have found that several impurities have an amphoteric behavior with the donor and acceptor energies in the energy bandgap. In order to analyze the role of the ionization energies in both the radiative and non-radiative processes, the host energy bandgap and the acceptor and the donor energies have been obtained as a function of the inward and outward impurity-S displacements. We carried out the analysis for both the natural and synthetic CZTS. The results show that the ionization energies are similar, whereas the energy band gaps are different
How similar can co-occurring species be in the presence of competition and ecological drift?

If two species live on a single resource, the one with a slight advantage will out-compete the other: complete competitors cannot coexist. This is known as the competitive exclusion principle. If no extinction occurs, it is because evolutionary adaptation to slightly different niches takes place. Therefore, it is widely accepted that ecological communities are assembled by evolutionary differentiation and progressive adaptation of species to different niches. However, some ecologists have recently challenged this classic paradigm highlighting the importance of chance and stochasticity. Using a synthetic  framework for community dynamics, here we show that, while deterministic descriptors predict coexistence, species similarity is limited in a more restrictive way in the presence of stochasticity. We analyse the stochastic extinction phenomenon, showing that extinction occurs as competitive overlap increases above a certain threshold well below its deterministic counterpart. We also prove that the extinction threshold cannot be ascribed only to demographic fluctuations around small population sizes. The more restrictive limit to species similarity is, therefore, a consequence of the complex interplay between competitive interactions and ecological drift. As a practical implication, we show that the existence of a stochastic limit to similarity has important consequences in the recovery of fragmented habitats
Use of the point defect model to interpret the iron oxidation kinetics under proton irradiation

This article concerns the study of iron corrosion in wet air under mega-electron-volt proton irradiation for different fluxes at room temperature and with a relative humidity fixed to 45%. Oxidized iron sample surfaces are characterized by ion beam analysis (Rutherford backscattering spectrometry and elastic recoil detection analysis), for the elemental analysis. The structural and physicochemical characterization is performed using the x-ray photoelectron spectroscopy and transmission electron microscopy techniques. We have also measured the iron oxidation kinetics. Radiation enhanced diffusion and transport processes have been evidenced. The modeling of the experimental data shows that the apparent oxygen diffusion coefficient increases whereas the oxygen transport velocity decreases as function of flux. Finally, the point defect model has been used to determine the electric field value in the samples. Results have shown that the transport process can be attributed to the presence of an electrical potential gradient
Mechanical studies of the multi-gap spoke cavity for European project HIPPI

Within the HIPPI (high intensity pulsed proton injector) project, supported by the 6th PCRD (framework programme for research and development) of the European Union, the German research centre Forschungszentrum Jülich proposed a multi-spoke H-cavity for the intermediate energy section (β = 0.5) of high power proton linear accelerators. The IPN Orsay is associated with FZ Jülich for the prototype design, and before that, all preliminary mechanical studies. A triple-spoke superconducting cavity has a more complicated geometry, compared to the same beta elliptical cavity. As a consequence the design requires some sophisticated tools, like the CAD (computer aided design) code Catia. In addition, in order to solve the specific mechanical problems imposed by external constraints, a sophisticated mechanical simulation tool Cast3m (Calcul et Analyse de Structure et Thermique par la méthode des Eléments Finis) is used [H. Gassot, in: Proceedings of the 8th European Particle Accelerator Conference, June 2002, Paris, [1]]. But no commercial modeling/FEA exchange software exists between Catia and Cast3m, so the first investigation consisted in the development of a dedicated program for this purpose. The mechanical behaviour of the triple spoke cavity in static and dynamic regime was studied with these codes. The results are presented and discussed in this report
GATE: improving the computational efficiency

5 pages, 3 figures, 3 tables - submitted to NIMA presented by S. StaelensInternational audienceGATE is a software dedicated to Monte Carlo simulations in Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET). An important disadvantage of those simulations is the fundamental burden of computation time. This manuscript describes three different techniques in order to improve the efficiency of those simulations. Firstly, the implementation of variance reduction techniques (VRTs), more speciﬁcally the incorporation of geometrical importance sampling, is discussed. After this, the newly designed cluster version of the GATE software is described. The experiments have shown that GATE simulations scale very well on a cluster of homogeneous computers. Finally, an elaboration on the deployment of GATE on the EGEE (Enabling Grids for E-Science in Europe) Grid will conclude the description of efficiency enhancement efforts. The three aforementioned methods improve the efficiency of GATE to a large extent and make realistic patient-speciﬁc overnight Monte Carlo simulations achievable
Phase transformations induced in relaxed amorphous silicon by indentation at room temperature

The deformation behavior of self-ion-implanted amorphous-Si (a-Si) has been studied using
spherical nanoindentation in both relaxed (annealed) and unrelaxed (as-implanted) a-Si.
Interestingly, phase transformations were clearly observed in the relaxed state, with the load–unload
curves from these samples displaying characteristic discontinuities and cross-sectional transmission
electron microscopy images indicating the presence of high-pressure crystalline phases Si-III and
Si-XII following pressure release. Thus, an amorphous to crystalline phase transformation has been
induced by indentation at room temperature. In contrast, no evidence of a phase transformation was
observed in unrelaxed a-Si, which appeared to deform via plastic flow of the amorphous phase.
Furthermore, in situ electrical measurements clearly indicate the presence of a metallic Si phase
during loading of relaxed a-Si but no such behavior was observed for unrelaxed a-S
Third-generation sequencing reveals extensive polycistronism and transcriptional  overlapping in a baculovirus

The Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is an insect-pathogen baculovirus. In this study, we applied the Oxford Nanopore Technologies platform for the analysis of the polyadenylated fraction of the viral transcriptome using both cDNA and direct RNA sequencing methods. We identified and annotated altogether 132 novel transcripts and transcript isoforms, including 4 coding and 4 non-coding RNA molecules, 47 length variants,  5 splice isoforms, as well as 23 polycistronic and 49 complex transcripts. All of the identified novel protein-coding genes were 5'-truncated forms of longer host  genes. In this work, we demonstrated that in the case of transcript start site isoforms, the promoters and the initiator sequence of the longer and shorter variants belong to the same kinetic class. Long-read sequencing also revealed a complex meshwork of transcriptional overlaps, the function of which needs to be clarified. Additionally, we developed bioinformatics methods to improve the transcript annotation and to eliminate the non-specific transcription reads generated by template switching and false priming
In situ control of As dimer orientation on Ge(100) surfaces

We investigated the preparation of single domain Ge(100):As surfaces in a metal-organic vapor phase epitaxy reactor. In situ reflection anisotropy spectra (RAS) of vicinal substrates change when arsenic is supplied either by tertiarybutylarsine or by background As4 during annealing. Low energy electron diffraction shows mutually perpendicular orientations of dimers, scanning tunneling microscopy reveals distinct differences in the step structure, and x-ray photoelectron spectroscopy confirms differences in the As coverage of the Ge(100): As samples. Their RAS signals consist of contributions related to As dimer orientation and to step structure, enabling precise in situ control over preparation of single domain Ge(100): As surfaces
Evaluation and improvement of empirical models of global solar irradiation: Case study northern Spain

This paper presents a new methodology to build parametric models to estimate global solar\ud
irradiation adjusted to specific on-site characteristics based on the evaluation of variable im-\ud
 portance. Thus, those variables higly correlated to solar irradiation on a site are implemented\ud
in the model and therefore, different models might be proposed under different climates. This\ud
methodology is applied in a study case in La Rioja region (northern Spain). A new model is\ud
proposed and evaluated on stability and accuracy against a review of twenty-two already exist-\ud
ing parametric models based on temperatures and rainfall in seventeen meteorological stations\ud
in La Rioja. The methodology of model evaluation is based on bootstrapping, which leads to\ud
achieve a high level of confidence in model calibration and validation from short time series (in\ud
 this case five years, from 2007 to 2011).\ud
  The model proposed improves the estimates of the other twenty-two models with average\ud
 mean absolute error (MAE) of 2.195 MJ/m2 day and average confidence interval width (95%\ud
  C.I., n=100) of 0.261 MJ/m2 day. 41.65% of the daily residuals in the case of SIAR and 20.12% in\ud
 that of SOS Rioja fall within the uncertainty tolerance of the pyranometers of the two networks\ud
(10% and 5%, respectively). Relative differences between measured and estimated irradiation\ud
on an annual cumulative basis are below 4.82%. Thus, the proposed model might be useful\ud
to estimate annual sums of global solar irradiation, reaching insignificant differences between\ud
 measurements from pyranometers
Electrochemical Impedance Characterization of Nafion-Coated Carbon Film Resistor Electrodes for Electroanalysis

Carbon film disk electrodes with Nafion coatings have been characterized by electrochemical impedance spectroscopy (EIS) with a view to a better understanding of their advantages and limitations in electroanalysis, particularly in anodic stripping voltammetry of metal ions. After initial examination by cyclic voltammetry, spectra were recorded over the full potential range in acetate buffer solution at the bare electrodes, electrodes electrochemically pretreated in acid solution, and Nafion-coated pretreated electrodes in the presence and absence of dissolved oxygen. EIS equivalent circuit analysis clearly demonstrated the changes between these electrode assemblies. In order to simulate anodic stripping voltammetry conditions, spectra were also obtained in the presence of cadmium and lead ions in solution at Nafion-coated electrodes, both after metal ion deposition and following re-oxidation. Permanent changes to the structure of the Nafion film occurred, which has implications for use of these electrode assemblies in anodic stripping voltammetry at relatively high trace metal ion concentrations.http://dx.doi.org/10.1002/elan.20040312
The joint role of trimming and constraints in robust estimation for mixtures of Gaussian factor analyzers.

Producción CientíficaMixtures of Gaussian factors are powerful tools for modeling an unobserved heterogeneous
population, offering – at the same time – dimension reduction and model-based clustering. The high prevalence of spurious solutions and the disturbing effects of outlying observations in maximum likelihood estimation may cause biased or misleading inferences. Restrictions for the component covariances are considered in order to avoid spurious solutions, and trimming is also adopted, to provide robustness against violations of normality assumptions of the underlying latent factors. A detailed AECM algorithm for this new approach is presented. Simulation results and an application to the AIS dataset show the aim and effectiveness of the proposed methodology.Ministerio de Economía y Competitividad and FEDER, grant MTM2014-56235-C2-1-P, and by Consejería de Educación de la Junta de Castilla y León, grant VA212U13, by grant FAR 2015 from the University of Milano-Bicocca and by grant FIR 2014 from the University of Catania
Time Series Classification by Class-Specific Mahalanobis Distance
  Measures

To classify time series by nearest neighbors, we need to specify or learn one
or several distance measures. We consider variations of the Mahalanobis
distance measures which rely on the inverse covariance matrix of the data.
Unfortunately --- for time series data --- the covariance matrix has often low
rank. To alleviate this problem we can either use a pseudoinverse, covariance
shrinking or limit the matrix to its diagonal. We review these alternatives and
benchmark them against competitive methods such as the related Large Margin
Nearest Neighbor Classification (LMNN) and the Dynamic Time Warping (DTW)
distance. As we expected, we find that the DTW is superior, but the Mahalanobis
distance measures are one to two orders of magnitude faster. To get best
results with Mahalanobis distance measures, we recommend learning one distance
measure per class using either covariance shrinking or the diagonal approach
Electrical and magnetic properties of the complete solid solution series
  between SrRuO3 and LaRhO3: Filling t2g versus tilting

A complete solid solution series between the t2g^4 perovskite ferromagnet
SrRuO3 and the diamagnetic t2g^6 perovskite LaRhO3 has been prepared. The
evolution with composition x in (SrRuO3)(1-x)(LaRhO3)(x) of the crystal
structure and electrical and magnetic properties has been studied and is
reported here. As x increases, the octahedral tilt angle gradually increases,
along with the pseudocubic lattice parameter and unit cell volume. Electrical
resistivity measurements reveal a compositionally driven metal to insulator
transition between x = 0.1 and 0.2. Ferromagnetic ordering gives over to glassy
magnetism for x > 0.3 and no magnetic ordering is found above 2 K for x > 0.5.
M_sat and Theta_CW decrease with increasing x and remain constant after x =
0.5. The magnetism appears poised between localized and itinerant behavior, and
becomes more localized with increasing x as evidenced by the evolution of the
Rhodes-Wohlfarth ratio. mu_eff per Ru is equal to the quenched spin-only S
value across the entire solid solution. Comparisons with Sr(1-x)Ca(x)RuO3
reinforce the important role of structural distortions in determining magnetic
ground state. It is suggested that electrical transport and magnetic properties
are not strongly coupled in this system
Baryon Mass Extrapolation

Consideration of the analytical properties of pion-induced baryon
self-energies leads to new functional forms for the extrapolation of light
baryon masses. These functional forms reproduce the leading non-analytic
behavior of chiral perturbation theory, the correct heavy-quark limit and have
the advantage of containing information on the extended structure of hadrons.
The forms involve only three unknown parameters which may be optimized by
fitting to present lattice data. Recent dynamical fermion results from CP-PACS
and UK-QCD are extrapolated using these new functional forms. We also use these
functions to probe the limit of the chiral perturbative regime and shed light
on the applicability of chiral perturbation theory to the extrapolation of
present lattice QCD results.Comment: LATTICE99 (QCD Spectrum and Quark Masses
Simulation of ion behavior in an open three-dimensional Paul trap using
  a power series method

Simulations of the dynamics of ions trapped in a Paul trap with terms in the
potential up to the order 10 have been carried out. The power series method is
used to solve numerically the equations of motion of the ions. The stability
diagram has been studied and the buffer gas cooling has been implemented by a
Monte Carlo method. The dipole excitation was also included. The method has
been applied to an existing trap and it has shown good agreement with the
experimental results and previous simulations using other methods
The asymptotic regimes of tilted Bianchi II cosmologies

In this paper we give, for the first time, a complete description of the dynamics of tilted spatially homogeneous cosmologies of Bianchi type II. The source is assumed to be a perfect fluid with equation of state $p = (\gamma -1) \mu$, where $\gamma$ is a constant. We show that unless the perfect fluid is stiff, the tilt destabilizes the Kasner solutions, leading to a Mixmaster-like initial singularity, with the tilt being dynamically significant. At late times the tilt becomes dynamically negligible unless the equation of state parameter satisfies $\gamma > {10/7}$. We also find that the tilt does not destabilize the flat FL model, with the result that the presence of tilt increases the likelihood of intermediate isotropization
Entanglement, Information and Multiparticle Quantum Operations

Collective operations on a network of spatially-separated quantum systems can
be carried out using local quantum (LQ) operations, classical communication
(CC) and shared entanglement (SE). Such operations can also be used to
communicate classical information and establish entanglement between distant
parties. We show how these facts lead to measures of the inseparability of
quantum operations, and argue that a maximally-inseparable operation on 2
qubits is the SWAP operation. The generalisation of our argument to N qubit
operations leads to the conclusion that permutation operations are
maximally-inseparable. For even N, we find the minimum SE and CC resources
which are sufficient to perform an arbitrary collective operation. These
minimum resources are 2(N-1) ebits and 4(N-1) bits, and these limits can be
attained using a simple teleportation-based protocol. We also obtain lower
bounds on the minimum resources for the odd case. For all $N{\geq}4$, we show
that the SE/CC resources required to perform an arbitrary operation are
strictly greater than those that any operation can establish/communicate
DNA single-strand break repair and spinocerebellar ataxia with axonal neuropathy-1

DNA single-strand breaks (SSBs) are the commonest DNA lesions arising spontaneously in cells, and if not repaired may block transcription or may be converted into potentially lethal/clastogenic DNA double-strand breaks (DSBs). Recently, evidence has emerged that defects in the rapid repair of SSBs preferentially impact the nervous system. In particular, spinocerebellar ataxia with axonal neuropathy (SCAN1) is a human disease that is associated with mutation of TDP1 (tyrosyl DNA phosphodiesterase 1) protein and with a defect in repairing certain types of SSBs. Although SCAN1 is a rare neurodegenerative disorder, understanding the molecular basis of this disease will lead to better understanding of neurodegenerative processes. Here we review recent progress in our understanding of TDP1, single-strand break repair (SSBR), and neurodegenerative disease
Overview of the ShARe/CLEF eHealth evaluation lab 2013

Discharge summaries and other free-text reports in healthcare transfer information between working shifts and geographic locations. Patients are likely to have difficulties in understanding their content, because of their medical jargon, non-standard abbreviations, and ward-specific idioms. This paper reports on an evaluation lab with an aim to support the continuum of care by developing methods and resources that make clinical reports in English easier to understand for patients, and which helps them in finding information related to their\ud
condition. This ShARe/CLEFeHealth2013 lab offered student mentoring and shared tasks: identification and normalisation of disorders (1a and 1b) and normalisation of abbreviations and acronyms (2) in clinical reports with respect to terminology standards in healthcare as well as information retrieval (3) to address questions patients may have when reading clinical reports. The focus on patients' information needs as opposed to the specialised information needs of physicians and other healthcare workers was the main feature of the lab distinguishing it from previous shared tasks. De-identied clinical reports for the three tasks were from US intensive care and originated from the MIMIC II database. Other text documents for Task 3 were from the Internet and originated from the Khresmoi project. Task 1 annotations originated from the ShARe annotations. For Tasks 2 and 3, new annotations, queries, and relevance\ud
assessments were created. 64, 56, and 55 people registered their interest in Tasks 1, 2, and 3, respectively. 34 unique teams (3 members per team on average) participated with 22, 17, 5, and 9 teams in Tasks 1a, 1b, 2 and 3, respectively. The teams were from Australia, China, France, India, Ireland, Republic of Korea, Spain, UK, and USA. Some teams developed\ud
and used additional annotations, but this strategy contributed to the system performance only in Task 2. The best systems had the F1 score of 0.75 in Task 1a; Accuracies of 0.59 and 0.72 in Tasks 1b and 2; and\ud
Precision at 10 of 0.52 in Task 3. The results demonstrate the substantial community interest and capabilities of these systems in making clinical\ud
reports easier to understand for patients. The organisers have made data and tools available for future research and development