julilili42/papers huggingface dataset:
Paleoenvironment and human hunting activity during MIS 2 in southern Jordan: Isotope records of prey remains and paleosols
2022-03-18

Stable carbon and oxygen isotopic compositions of faunal remains unearthed from the rock shelter site of Tor Hamar in southern Jordan were analyzed for reconstructing paleoenvironments and hunting activities in the region. The site is located at the Jebel Qalkha area and has archaeological deposits dated to the Early Upper Paleolithic (ca. 38–37 ka) and the Epipaleolithic (ca. 24–15 ka) periods. The excavations at the site have yielded remains of animal prey in addition to lithic tools enabling estimation of paleoenvironments during the late Pleistocene. Despite the poorly preserved condition of animal remains, which is typical of this region, we performed isotope analysis together with identification by morphological analysis and peptide sequencing on animal tooth fragments in addition to the isotope analysis on paleosol organic matters. The in-situ paleosol isotope data points to an environmental shift from a wetter condition in the older period yielding the Qalkhan artifacts (∼24–18 ka) to a drier condition in the later period yielding the Mushabian artifacts (∼15.5–15.2 ka). The results are consistent with the Pleistocene lake-level shift of Lake Lisan and its pollen data that indicate a sudden shift towards a drier condition since ∼15–16 ka. This evidence points to a paleoclimatic trend opposite to the one in Mediterranean coast and an even more prominent shift than is recorded in Soreq and Tzavoa cave speleothems during the terminal Pleistocene of the northern Negev. Yet the environmental shift around Tor Hamar was not mirrored in gazelle isotope data. The data show among the greatest isotopic variations in Levant suggesting a change in human hunting strategy that possibly targeted multiple different species of genus Gazella and/or a use of different hunting areas particularly between the Qalkhan and the Mushabian periods.
Slick Potassium Channels Control Pain and Itch in Distinct Populations of Sensory and Spinal Neurons in Mice
2022-03-18

Background Slick, a sodium-activated potassium channel, has been recently identified in somatosensory pathways, but its functional role is poorly understood. The authors of this study hypothesized that Slick is involved in processing sensations of pain and itch. Methods Immunostaining, in situ hybridization, Western blot, and real-time quantitative reverse transcription polymerase chain reaction were used to investigate the expression of Slick in dorsal root ganglia and the spinal cord. Mice lacking Slick globally (Slick –/– ) or conditionally in neurons of the spinal dorsal horn (Lbx1-Slick –/– ) were assessed in behavioral models. Results The authors found Slick to be enriched in nociceptive Aδ-fibers and in populations of interneurons in the spinal dorsal horn. Slick –/– mice, but not Lbx1-Slick –/– mice, showed enhanced responses to noxious heat in the hot plate and tail-immersion tests. Both Slick –/– and Lbx1-Slick –/– mice demonstrated prolonged paw licking after capsaicin injection (mean ± SD, 45.6 ± 30.1 s [95% CI, 19.8 to 71.4]; and 13.1 ± 16.1 s [95% CI, 1.8 to 28.0]; P = 0.006 [Slick –/– {n = 8} and wild-type {n = 7}, respectively]), which was paralleled by increased phosphorylation of the neuronal activity marker extracellular signal–regulated kinase in the spinal cord. In the spinal dorsal horn, Slick is colocalized with somatostatin receptor 2 (SSTR2), and intrathecal preadministration of the SSTR2 antagonist CYN-154806 prevented increased capsaicin-induced licking in Slick –/– and Lbx1-Slick –/– mice. Moreover, scratching after intrathecal delivery of the somatostatin analog octreotide was considerably reduced in Slick –/– and Lbx1-Slick –/– mice (Slick –/– [n = 8]: 6.1 ± 6.7 bouts [95% CI, 0.6 to 11.7]; wild-type [n =8]: 47.4 ± 51.1 bouts [95% CI, 4.8 to 90.2]; P = 0.039). Conclusions Slick expressed in a subset of sensory neurons modulates heat-induced pain, while Slick expressed in spinal cord interneurons inhibits capsaicin-induced pain but facilitates somatostatin-induced itch. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New
Polyhedral Divisors and Algebraic Torus Actions
2022-03-18

We provide a complete description of normal affine varieties with effective algebraic torus action in terms of what we call proper polyhedral divisors on semiprojective varieties. Our theory extends classical cone constructions of Dolgachev, Demazure and Pinkham to the multigraded case, and it comprises the theory of affine toric varieties.
X-ray properties of NGC 300 I. Global properties of X-ray point sources and their optical counterparts
2022-03-18

We present X-ray properties of NGC 300 point sources, extracted from 66 ksec of XMM-Newton data taken in 2000 December and 2001 January. A total of 163 sources were detected in the energy range of 0.3-6 kev. We report on the global properties of the sources detected inside the D25 optical disk, such as the hardness ratio and X-ray fluxes, and on the properties of their optical counterparts found in B, V, and R images from the 2.2m MPG/ESO telescope. Furthermore, we cross-correlate the X-ray sources with SIMBAD, the USNO-A2.0 catalog, and radio catalogues.
Is large-scale rapid CoV-2 testing a substitute for lockdowns?
2022-03-18

Background Various forms of contact restrictions have been adopted in response to the Covid-19 pandemic. Around February 2021, rapid testing appeared as a new policy instrument. Some claim it may serve as a substitute for contact restrictions. We study the strength of this argument by evaluating the effects of a unique policy experiment: In March and April 2021, the city of Tübingen set up a testing scheme while relaxing contact restrictions. Methods We compare case rates in Tübingen county to an appropriately identified control unit. We employ the synthetic control method. We base interpretations of our findings on an extended SEIR model. Findings The experiment led to an increase in the reported case rate. This increase is robust across alternative statistical specifications. This is also due to more testing leading initially to more reported cases. An epidemiological model that corrects for ‘more cases due to more testing’ and ‘reduced testing and reporting during the Easter holiday’ confirms that the overall effect of the experiment led to more infections. Interpretation The number of rapid tests were not sufficiently high in this experiment to compensate for more contacts and thereby infections caused by relaxing contact restrictions.
Ion Mobility Studies of Pyrroloquinoline Quinone Aza-Crown Ether–Lanthanide Complexes
2022-03-18

Lanthanide-dependent enzymes and their biomimetic complexes have arisen as an interesting target of research in the past decade. These enzymes, specifically, pyrroloquinoline quinone (PQQ)-bearing methanol dehydrogenases, efficiently convert alcohols to the respective aldehydes. To rationally design bioinspired alcohol dehydrogenation catalysts, it is imperative to understand the species involved in catalysis. However, given the extremely flexible coordination sphere of lanthanides, it is often difficult to assess the number and nature of the active species. Here, we show how such questions can be addressed by using a combination of ion mobility spectrometry, mass spectrometry, and quantum-chemical calculations to study the test systems PQQ and lanthanide-PQQ-crown ether ligand complexes. Specifically, we determine the gas-phase structures of [PQQH<sub>2</sub>]<sup>-</sup>, [PQQH<sub>2</sub>+H<sub>2</sub>O]<sup>-</sup>, [PQQH<sub>2</sub>+MeOH]<sup>-</sup>, [PQQ-15c5+H]<sup>+</sup>, and [PQQ-15c5+Ln+NO<sub>3</sub>]<sup>2+</sup> (Ln = La to Lu, except Pm). In the latter case, a trend to smaller collision cross sections across the lanthanide series is clearly observable, in line with the well-known lanthanide contraction. We hope that in the future such investigations will help to guide the design and understanding of lanthanide-based biomimetic complexes optimized for catalytic function.
Heterospecific eavesdropping of jays (Garrulus glandarius) on blackbird (Turdus merula) mobbing calls
2022-03-18

Abstract Heterospecifics eavesdrop on mobbing calls and respond with appropriate behavior, but the functional aspects are less studied. Here, I studied whether jays ( Garrulus glandarius ) eavesdrop on blackbird ( Turdus merula ) mobbing calls in comparison to blackbird song. Furthermore, it was studied whether jays provided with extra information about predators differ in their response. Three different experimental designs were carried out: (1) control playback of blackbird song to control for the species’ presence, (2) experimental playback of different mobbing events of blackbirds towards different predators, (3) experimental playback similar to (2) but combined with different predator models. In the combined experiments, mobbing calls were tied to the respective visual stimuli. Comparing the experiments with and without predator presentation, a similar number of jays occurred during the playback-only experiment ( n = 7) and the playback combined with model presentation ( n = 6). However, during the playback-only experiment, jays approached the speaker closer and stayed for longer time in the nearer surrounding. These results show that jays need extra information to make an informed decision.
When Sharing Isn't Caring: How Educational Institutions Share Students’ Personally Identifiable Information on Facebook
2022-03-18

Schools and school districts now use social media for a variety of reasons, but alongside the benefits that accompany these K-12 educational institutions' social media use come questions about privacy and safety. We use a dataset of around 18 million posts by United States schools and districts on Facebook to explore how these posts might risk the privacy and safety of students by depicting (showing a photo of a student's face) or identifying (by depicting a student and naming them with their first and last name) them in public posts. We also examine which Facebook page characteristics and structural factors (i.e., the size of the district) might be associated with posts that depict or identify students. Through our sequential mixed methods design involving qualitative coding of a sample of 400 posts, we found that around 4.9 million posts depict students and that around 725,000 posts identify students. Districts with a higher student poverty rate and districts that post more were more likely to depict students in any one post. We discuss these findings and suggest directions for future research in terms of data ethics.
Spherical Hartree-Fock calculations with linear momentum projection before the variation.Part I: Energies, form factors, charge densities and mathematical sum rules
2022-03-18

Spherical Hartree--Fock calculations with projection onto zero total linear momentum before the variation are performed for the nuclei 4He, 12C, 16O, 28Si, 32S and 40Ca using a density--independent effective nucleon--nucleon interaction. The results are compared to those of usual spherical Hartree--Fock calculations subtracting the kinetic energy of the center of mass motion either before or after the variation and to the results obtained analytically with oscillator occupations. Total energies, hole--energies, elastic charge form factors and charge densities and the mathematical Coulomb sum rules are discussed.
Topologically non-trivial field configurations - interplay of vortices and Dirac eigenmodes
2022-03-18

Gluon field configurations with non-trivial topology like instantons, magnetic monopoles and center vortices play a crucial role in QCD and, in particular, for the spontaneous breaking of chiral symmetry. Moreover, center vortices are strongly correlated with confinement. We present evidence, that there is a deep connection between the topology of gauge fields and center vortices. We use the chirally improved lattice Dirac operator to compute eigenvectors and eigenvalues of various lattice gauge field configurations. Removing vortices from thermalized configurations also removes the topological content of the gauge field. As a consistency check, we apply random changes to the raw configurations.
Noncommutative continuous Bernoulli shifts
2022-03-18

We introduce a non-commutative extension of Tsirelson-Vershik's noises, called (non-commutative) continuous Bernoulli shifts. These shifts encode stochastic independence in terms of commuting squares, as they are familiar in subfactor theory. Such shifts are, in particular, capable of producing Arveson's product system of type I and type II. We investigate the structure of these shifts and prove that the von Neumann algebra of a (scalar-expected) continuous Bernoulli shift is either finite or of type III. The role of (`classical') stationary flows for Tsirelson-Vershik's noises is now played by cocycles of continuous Bernoulli shifts. We show that these cocycles provide an operator algebraic notion for Levy processes. They lead, in particular, to units and `logarithms' of units in Arveson's product systems. Furthermore, we introduce (non-commutative) white noises, which are operator algebraic versions of Tsirelson's `classical' noises. We give examples coming from probability, quantum probability and from Voiculescu's theory of free probability. Our main result is a bijective correspondence between additive and unital shift cocycles. For the proof of the correspondence we develop tools which are of interest on their own: non-commutative extensions of stochastic Ito integration, stochastic logarithms and exponentials.
A novel improved action for SU(3) lattice gauge theory
2022-03-18

SU(3) lattice gauge theory is studied by means of an improved action where a Wilson loop is supplemented to the standard plaquette term. By contrast to earlier studies using a tree level improvement, the prefactor of the Wilson term is determined by minimizing the breaking of rotational symmetry detected from the static quark-antiquark potential. On coarse lattices, the novel action is superior to the Iwasaki action and comparable with DBW2 action. The scaling behavior of the novel action is studied by using the static quark potential and the ratio of the deconfinement temperature and the string tension.
Induction and Mutually Obstructing Equilibria
2022-03-18

A unified, consistent and simple view of the Faraday law of induction is presented, which consists of two points: discriminating the lab- from the rest-frame electric field and understanding it is the impossibility for both fields to vanish simultaneously, which generates and maintains the circular current. A number of illustrative examples are considered, including a mechano-electric pendulum to exhibit periodic and reversible conversion between electrical and mechanical energy.
On local CR-transformations of Levi-degenerate group orbits in compact Hermitian symmetric spaces
2022-03-18

Let be a real-analytic hypersurface in or, more generally, a CR-submanifold in a complex manifold of arbitrary CR-codimension. This paper addresses the question, when a local biholomorphic map between open sets in sending an open piece of into extends to a global biholomorphic self-map of preserving . We give answers for a large class of Levi-degenerate group orbits in compact Hermitian symmetric spaces.
Multi-excited random walks on integers
2022-03-18

We introduce a class of nearest-neighbor integer random walks in random and non-random media, which includes excited random walks considered in the literature. At each site the random walker has a drift to the right, the strength of which depends on the environment at that site and on how often the walker has visited that site before. We give exact criteria for recurrence and transience and consider the speed of the walk.
Research compendium for 'Practical and technical aspects for the 3D scanning of lithic artefacts using micro-computed tomography techniques and laser light scanners for subsequent geometric morphometric analysis. Introducing the StyroStone protocol'
2022-03-18

Abstract: Here, we present a new method to scan a large number of lithic artefacts using three-dimensional (3D) scanning technology. Despite the rising use of high-resolution 3D surface scanners in archaeological sciences, no virtual studies have focused on the 3D digitization and analysis of small lithic implements such as bladelets, microblades, and microflakes. This is mostly due to difficulties in creating reliable 3D meshes of these artefacts resulting from several inherent features (i.e., size, translucency, and acute edge angles), which compromise the efficiency of structured light or laser scanners and photogrammetry. Our new protocol StyroStone addresses this problem by proposing a step-by-step procedure relying on the use of micro-computed tomographic technology, which is able to capture the 3D shape of small lithic implements in high detail. We tested a system that enables us to scan hundreds of artefacts together at once within a single scanning session lasting a few hours. As also bigger lithic artefacts (i.e., blades) are present in our sample, this protocol is complemented by a short guide on how to effectively scan such artefacts using a structured light scanner (Artec Space Spider). Furthermore, we estimate the accuracy of our scanning protocol using principal component analysis of 3D Procrustes shape coordinates on a sample of meshes of bladelets obtained with both micro-computed tomography and another scanning device (i.e., Artec Micro). A comprehensive review on the use of 3D geometric morphometrics in lithic analysis and other computer-based approaches is provided in the introductory chapter to show the advantages of improving 3D scanning protocols and increasing the digitization of our prehistoric human heritage. Content List: S1. Step-by-step protocol entitled ‘StyroStone: A protocol for scanning and extracting three-dimensional meshes of stone artefacts using Micro-CT scanners’. Also available on protocols.io (dx.doi.org/10.17504/protocols.io.bzbfp2jn); S2. Dataset with all raw semilandmark coordinate data (in .xlsx format) used in the validation study; S3. AGMT3D project. The file “Validation Protocol-MorphoProject.mat” can be used to open the project in the software AGMT3D; S4. Dataset in .csv format of the principal component score data of the validation study; S5. R script used to create Figure 2 using the R package ggplot2; S6. 3D models of the experimental bladelets obtained with the Micro-CT scanner used in the validation study. Both .ply and .wrl formats are provided; S7. 3D models of the experimental bladelets obtained with the Artec Micro scanner used in the validation study. Both .ply and .wrl formats are provided.
Evolution of Planets in Disks
2022-03-18

The main properties of the observed extrasolar planets are reviewed with respect to their relevance to the formation scenario of planetary systems. Results of numerical computations of embedded planets in viscously evolving disks are presented. Emphasis is given to the accretion and migration process. New calculations on inviscid disks are shown. The second part of the talk concentrates on resonant planetary systems. Among the observed extrasolar systems there are 3 confirmed cases, Gl 876, HD 82943 and 55 Cnc, where the planets orbit their central star in a low order mean motion resonance. Results of numerical simulations modeling the formation and evolution of such systems are presented.
BdG equations within lattice Hubbard model for the description of $π$-states in nanoscale S-FF-S junctions
2022-03-18

We calculate the persistent currents in structures (S denotes the superconductor in a closed ring geometry, F the ferromagnet in a two dimensional geometry, and the arrows the alignment of exchange field) as a function of the applied magnetic flux, self consistently by solving the Bogoliubov-de Gennes equations within the two dimensional Hubbard model. The local current shows a sign change i.e. a 0 to transition in the parallel alignment of the magnetizations and it does not change sign in antiparallel alignment.
Four Numerical Approaches for Solving the Radiative Transfer Equation in Magnetized White-Dwarf Atmospheres
2022-03-18

We compare four different methods to calculate radiative transfer through a magnetized stellar atmosphere, and apply them to the case of magnetic white dwarfs. All methods are numerically stable enough to allow determination of the magnetic field structure, but distinctions between faster, simplifying, methods, and elaborate, but more CPU-time consuming, methods, can be made.
Hyperelliptic Theta-Functions and Spectral Methods
2022-03-18

A code for the numerical evaluation of hyperelliptic theta-functions is presented. Characteristic quantities of the underlying Riemann surface such as its periods are determined with the help of spectral methods. The code is optimized for solutions of the Ernst equation where the branch points of the Riemann surface are parameterized by the physical coordinates. An exploration of the whole parameter space of the solution is thus only possible with an efficient code. The use of spectral approximations allows for an efficient calculation of all quantities in the solution with high precision. The case of almost degenerate Riemann surfaces is addressed. Tests of the numerics using identities for periods on the Riemann surface and integral identities for the Ernst potential and its derivatives are performed. It is shown that an accuracy of the order of machine precision can be achieved. These accurate solutions are used to provide boundary conditions for a code which solves the axisymmetric stationary Einstein equations. The resulting solution agrees with the theta-functional solution to very high precision.
Dynamical Evolution of Planets in Disks
2022-03-18

We study the evolution of a system consisting of two protoplanets still embedded in a protoplanetary disk. Results of two different numerical approaches are presented. In the first kind of model the motion of the disk material is followed by fully viscous hydrodynamical simulations, and the planetary motion is determined by N-body calculations including exactly the gravitational potential from the disk material. In the second kind we only solve the N-body part and add additional analytically given forces which model the effect of the torques of the disk. This type of modeling is of course orders of magnitudes faster than the full hydro-model. Another advantage of this two-fold approach is the possibility of adjusting the otherwise unknown parameters of the simplified model. The results give very good agreement between the methods. Using two different initial setups for the planets and disk, we obtain in the first case a resonant trapping into the 3:1 resonance, and in the second case a trapping into the 2:1 resonance. Resonant capture leads to a rise in the eccentricity and to an alignment of the of the spatial orientation of orbits. The characteristics of the numerical results agree very favorably with those of 3 observed planetary systems (GJ 876, HD 82943, and 55 Cnc) known to be in mean motion resonances.