Asymmetry In Production Research Articles

Validity of Visual Assessment of Sit to Stand After Hip Fracture.

When treating older adults post-hip fracture, physical therapists routinely assess the sit-to-stand (STS) task using observational analysis. Studies have demonstrated that significant movement asymmetries in ground reaction force production of the fractured lower limb persist during STS, even though individuals may rise independently. To date, the validity of therapist judgments of lower limb force during STS has not been addressed. The purpose of this observational cohort study was to determine the accuracy of physical therapists' observational assessments of STS for detecting the involved limb and its ground reaction force contribution in older adults post-hip fracture. Eighteen home health physical therapists assessed 10 videotapes of older adults post-hip fracture rising from sitting and judged the side of involvement and the amount of ground reaction force generated by the fractured lower limb. Each videotape was synchronized with its respective force data. A wide spectrum of asymmetry in rising was represented in the test videos. Before making these judgments, the therapists viewed a separate set of training videos and received instructions in the use of specific visual cues to assist with subsequent judgments. Therapists judged the involved side correctly 74% of the time. Mean accuracy in judging ground reaction force output was 39% across all therapists. Force symmetry did not significantly influence accuracy of force judgments. Inaccurate judgments of force may limit therapeutic intensity and minimize the potential for developing motor strategies that favor force production of the involved limb. Augmenting observational analysis of STS with quantitative data could assist in optimizing restorative function. Judgments of lower limb ground reaction force output during STS based on observation alone are not valid and may need to be supplemented with quantitative data.

Production asymmetry of \u03bd\u03c4 neutrinos and {overline{nu}}_{tau } antineutrinos from a fixed target experiment SHiP

We discuss how to calculate cross sections as well as rapidity, transverse momentum and energy distributions of ντ and {overline{nu}}_{tau } produced from the direct {D}_s^{pm}to {nu}_{tau }/{overline{nu}}_{tau } and chain {D}_s^{pm}to {tau}^{+}/{tau}^{-}to {nu}_{tau }/{overline{nu}}_{tau } decays in p+96 Mo scattering with proton beam Elab = 400 GeV i.e. at {sqrt{s}}_{NN} = 27.4 GeV. The τ decays are simulated with the help of the Tauola code and include multiple decay channels of τ in amounts proportional to their branching ratios. In our calculations we include {D}_s^{pm } from charm fragmentation c → {D}_s^{+} and overline{c}to {D}_s^{-} as well as those from subleading fragmentation of strange quarks/antiquarks s → {D}_s^{-} and overline{s}to {D}_s^{+} . The sne overline{s} asymmetry of the strange quark content of proton is included. The different contributions to {D}_s^{+} and {nu}_{tau }/{overline{nu}}_{tau } are shown explicitly. We discuss and quantify a not discussed so far effect of asymmetries for production of ντ and {overline{nu}}_{tau } caused by subleading fragmentation mechanism and discuss related uncertainties. A potential measurement of the asymmetry is discussed. Estimates of a number of observed {nu}_{tau }/{overline{nu}}_{tau } in the {nu}_{tau }/{overline{nu}}_{tau } +208Pb reaction, with 2m long target are given with the help of the NuWro program. We refer also to the production of the high-energy (anti)neutrinos in the atmosphere.

Measurement of the Bc− meson production fraction and asymmetry in 7 and 13 TeV pp collisions

The production fraction of the Bc− meson with respect to the sum of B− and B¯0 mesons is measured in both 7 and 13 TeV center-of-mass (c.m.) energy pp collisions produced by the Large Hadron Collider (LHC), using the LHCb detector. The rate, approximately 3.7 per mille, does not change with energy, but shows a transverse momentum dependence. The Bc−−Bc+ production asymmetry is also measured and is consistent with zero within the determined statistical and systematic uncertainties of a few percent.1 MoreReceived 30 October 2019DOI:https://doi.org/10.1103/PhysRevD.100.112006Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.© 2019 CERN, for the LHCb CollaborationPhysics Subject Headings (PhySH)Research AreasParticle interactionsParticle productionQuantum chromodynamicsStrong interactionParticles & Fields

In-Water and On-Land Swimmers' Symmetry and Force Production.

Although performance and biomechanical evaluations are becoming more swimming-specific, dryland testing permits monitoring of a larger number of performance-related variables. However, as the degree of comparability of measurements conducted in-water and on land conditions is unclear, we aimed to assess the differences between force production in these two different conditions. Twelve elite swimmers performed a 30 s tethered swimming test and four isokinetic tests (shoulder and knee extension at 90 and 300°/s) to assess peak force, peak and average torque, and power symmetry index. We observed contralateral symmetry in all the tests performed, e.g., for 30 s tethered swimming and peak torque shoulder extension at 90°/s: 178 ± 50 vs. 183 ± 56 N (p = 0.38) and 95 ± 37 vs. 94 ± 35 N × m (p = 0.52). Moderate to very large direct relationships were evident between dryland testing and swimming force production (r = 0.62 to 0.96; p < 0.05). Swimmers maintained similar symmetry index values independently of the testing conditions (r = −0.06 to −0.41 and 0.04 to 0.44; p = 0.18–0.88). Asymmetries in water seems to be more related to technical constraints than muscular imbalances, but swimmers that displayed higher propulsive forces were the ones with greater force values on land. Thus, tethered swimming and isokinetic evaluations are useful for assessing muscular imbalances regarding propulsive force production and technical asymmetries.

Double spin asymmetry in dihadron production in SIDIS off a longitudinally polarized nucleon target

In this paper we study the double longitudinal spin asymmetry of dihadron production in semi-inclusive deep inelastic scattering (SIDIS). We calculate a unknown twist-3 dihadron fragmentation function $\widetilde{D}^\sphericalangle$ within a spectator model which has been used successfully in describing the dihadron production in both the unpolarized and the single polarized processes. The collinear picture, in which the transverse momentum of the final state hadron pair is integrated out, has been considered. The $\cos\phi_R$ azimuthal asymmetry arises from the coupling $e_L H_1^\sphericalangle$ and the coupling $g_1 \widetilde{D}^\sphericalangle$ is studied. We estimate the $\cos\phi_R$ asymmetry at the kinematics of COMPASS and compare with the data. The prediction at the future Electron Ion Collider (EIC) has also been presented.

Tone mergers in Hong Kong Cantonese: An asymmetry of production and perception.

This paper examines the tone-merging phenomenon in Hong Kong Cantonese. Both perception and production tasks were administered to 120 participants with ages ranging from 20 to 58 years. After considering the complicated interplay of perception and production confusion, the paper provides statistical evidence that three tonal contrasts have undergone merging in contemporary Hong Kong Cantonese. They are Full-merger T2 and T5, where contrast is collapsed in both perception and production; Partial-merger T3 and T6, where contrast is collapsed in production only; and Near-merger T4 and T6, where contrast is collapsed in perception but maintained in production.

CosϕR asymmetry of dihadron production in double longitudinally polarized SIDIS

We present a study on the double longitudinal-spin asymmetry of dihadron production in semi-inclusive deep inelastic scattering, in which the total transverse momentum of the final-state hadron pairs is integrated out. In particular, we investigate the origin of the $\cos\phi_R$ azimuthal asymmetry for which we take into account the coupling of the helicity distribution $g_1$ and the twist-3 dihadron fragmentation function $\widetilde{D}^{\sphericalangle}$. We calculate the $s$-wave and $p$-wave interference term $\widetilde{D}^{\sphericalangle}_{ot}$ in a spectator model. We estimate the $\cos\phi_R$ asymmetry at the kinematics of COMPASS which is collecting data on dihadron production in polarized deep inelastic scattering. The prediction of the same asymmetry at JLab 12GeV and a future EIC are also presented. Our study indicates that measuring the $\cos\phi_R$ asymmetry in SIDIS may be a ideal way to probe the dihadron fragmentation function $\widetilde{D}^{\sphericalangle}$.

PDF profiling using the forward-backward asymmetry in Neutral Current Drell-Yan production

Non-perturbative QCD effects from Parton Distribution Functions (PDFs) may be constrained by using high-statistics Large Hadron Collider (LHC) data. Drell-Yan (DY) measurements in the Charged Current (CC) case provide one of the primary means to do this, in the form of the lepton charge asymmetry. We investigate here the impact of measurements in Neutral Current (NC) DY data mapped onto the Forward-Backward Asymmetry (AFB) on PDF determinations, by using the open source fit platform xFitter. We demonstrate the potential impact of AFB data on PDF determinations and perform a thorough analysis of related uncertainties.

Vector-like quark interpretation of excess in Higgs signal strength

There is a +2σ deviation in the average Higgs-signal strength for all the 7+8+13 TeV data up to Summer 2018. We find that a slight reduction of the bottom-Yukawa coupling can fit the data better than the standard model. We suggest an extension with a vector-like quark doublet, of which the right-handed component of b′ mixes nonnegligibly with the standard model b quark. We show that the mixing would induce a reduction of the bottom Yukawa coupling. Simultaneously, the coupling of the Z boson to the right-handed b quark increases, which could reduce the forward-backward asymmetry of bottom production at LEP and bring it closer to the experimental value. However, such a mixing is in tension with the ratio Rb of the partial width Z→bb¯ to the total hadronic width, and with the total hadronic width of the Z boson.

Evaluation of Power Production Asymmetry during Cycling in Persons with Multiple Sclerosis.

Lower limb asymmetries have been observed in persons with multiple sclerosis (PwMS), and have been associated with mobility impairment. An incremental cycling test was performed on a cycle ergometer to determine peak power output (PPO) and peak oxygen consumption (VO2peak). Then, participants cycled at 50%, 60%, and 70% of their PPO to assess the contribution of each lower limb to power production. Two-way repeated measures ANOVA was used to detect group × intensity differences in power production asymmetry. Eight PwMS and six healthy individuals (Non-MS) completed the study. No statistically significant (p > 0.05) group × intensity interactions or main effects were present when examining between-limb differences in power production. The current data do not indicate a statistically significant difference in power production asymmetry between groups and exercise intensities. Previous research has established a 10% difference between contralateral limbs as a threshold for asymmetry. The average asymmetry in power production in PwMS exceeded the 10% threshold at all measured outputs, suggesting the presence of asymmetry in power production.

Beam-helicity asymmetries for single-hadron production in semi-inclusive deep-inelastic scattering from unpolarized hydrogen and deuterium targets

A measurement of beam-helicity asymmetries for single-hadron production in deep-inelastic scattering is presented. Data from the scattering of 27.6 GeV electrons and positrons off gaseous hydrogen and deuterium targets were collected by the HERMES experiment. The asymmetries are presented separately as a function of the Bjorken scaling variable, the hadron transverse momentum, and the fractional energy for charged pions and kaons as well as for protons and anti-protons. These asymmetries are also presented as a function of the three aforementioned kinematic variables simultaneously.

Analysis of tandem polling queues with finite buffers

We analyze a tandem polling queue with two stations operating under three different polling strategies, namely: (1) Independent polling, (2) Synchronous polling, and (3) Out-of-sync polling. Under Markovian assumptions of arrival and service times, we conduct an exact analysis using Matrix Geometric method to determine system throughput, mean queue lengths, and mean waiting times. Through numerical experiments, we compare the performance of the three polling strategies and the effect of buffer sizes on performance. We observe that the independent polling strategy generally performs better than the other strategies, however, under certain settings of product asymmetry, other strategies yield better performance.

Probing the linear polarization of photons in ultraperipheral heavy ion collisions

We propose to measure the linear polarization of the external electromagnetic fields of a relativistic heavy ion through azimuthal asymmetries in dilepton production in ultraperipheral collisions. The asymmetries estimated with the equivalent photon approximation are shown to be sizable.

ГОМЕОСТАТИЧНИЙ МЕХАНІЗМ КООРДИНАЦІЇ РЕЗУЛЬТАТІВ В СИСТЕМІ МІЖНАРОДНОЇ ЕКОНОМІЧНОЇ ДІЯЛЬНОСТІ ПІДПРИЄМСТВА

Basing on the homeostatic approach, the processes of formation, movement, correlation and interdependence of the productive flows in the systemic complex of international economic activity of enterprises are investigated in the article; the homeostatic model is developed where the dynamic equilibrium is supported by the mechanism of self-regulation of the productive flows. Considering the international economic activity of the enterprise as a systemic complex including the enterprise, the external market and the institutional & regulatory space of their interaction, the mechanism of realization of its functioning goals and coordinating of the productive flows within the complex are revealed. Available scientific developments aimed to form a modern model basis for management of compound socio-economic systems do not fully reflect the specifics of inter-system interaction of elements in the systemic complex of international economic activity of enterprises what requires additional research and necessity to apply a new methodology. Determining of critical zones in the functioning of production and market systems allows us to identify the necessary preconditions for supporting their homeostasis and integrating into the systemic complex of international economic activity of an enterprise: 1. mirror inclusion into the systemic complex of production and market systems, when the output results of the first one are the input for the second; 2. formation of double feedback between production and market systems; 3. parameters asymmetry of production and market systems functioning is not to exceed their certain critical boundary. Homeostatic model of regulation and coordination of results in the system of international economic activity of the enterprise includes: - regulatory parameter – the result of the system complex functioning (object of management); - management body (subject of system complex management); - two controlled inversing systems or two regulators of productive flows in the international economic activity system complex.

From [formula omitted] production asymmetry at the LHC to prompt ντ at IceCube

The description of the heavy meson production at large energies and forward rapidities at the LHC is fundamental to derive realistic predictions of the prompt atmospheric neutrino flux at the IceCube Observatory. In particular, the prompt tau neutrino flux is determined by the decay of Ds mesons produced in cosmic ray–air interactions at high energies and large values of the Feynman-xF variable. Recent data of the LHCb Collaboration indicate a production asymmetry for Ds+ and Ds− mesons, which cannot be explained in terms of the standard modeling of the hadronization process. In this paper we demonstrate that this asymmetry can be described assuming an asymmetric strange sea (s(x)≠s¯(x)) in the proton wave function and taking into account the dominant charm and subdominant strange fragmentation into Ds mesons. Moreover, we show that the strange quark fragmentation contribution is dominant at large-xF (≥0.3). The prompt ντ flux is calculated and the enhancement associated with the strange quark fragmentation contribution, disregarded in previous calculations, is estimated. The considered scenario leads to quite sizable enhancement of the high-energy τ-neutrino flux.

Measurement of the mass and production rate of Ξb− baryons

The first measurement of the production rate of $\Xi_b^-$ baryons in $pp$ collisions relative to that of $\Lambda_b^0$ baryons is reported, using data samples collected by the LHCb experiment, and corresponding to integrated luminosities of $1$, $2$ and $1.6$ fb$^{-1}$ at $\sqrt{s}=7,~8$ and $13$ TeV, respectively. In the kinematic region $2 < \eta < 6$ and $p_{\rm T}<20$ GeV/$c$, we measure \begin{align*} \frac{f_{\Xi_b^-}}{f_{\Lambda_b^0}}\frac{{\mathcal{B}}(\Xi_b^-\to J/\psi\Xi^-)}{{\mathcal{B}}(\Lambda_b^0\to J/\psi\Lambda)} &= (10.8\pm0.9\pm0.8)\times10^{-2}~~[\sqrt{s}=7,8~{\rm TeV}],\\ \frac{f_{\Xi_b^-}}{f_{\Lambda_b^0}}\frac{{\mathcal{B}}(\Xi_b^-\to J/\psi\Xi^-)}{{\mathcal{B}}(\Lambda_b^0\to J/\psi\Lambda)} &= (13.1\pm1.1\pm1.0)\times10^{-2}~~[\sqrt{s}=13~{\rm TeV}], \end{align*} where $f_{\Xi_b^-}$ and $f_{\Lambda_b^0}$ are the fragmentation fractions of $b$ quarks into $\Xi_b^-$ and $\Lambda_b^0$ baryons, respectively, ${\mathcal{B}}$ represents branching fractions, and the uncertainties are due to statistical and experimental systematic sources. The values of $f_{\Xi_b^-}/f_{\Lambda_b^0}$ are obtained by invoking SU(3) symmetry in the $\Xi_b^-\to J\psi\Xi^-$ and $\Lambda_b^0\to J/\psi\Lambda$ decays. Production asymmetries between $\Xi_b^-$ and $\bar{\Xi}_b^+$ baryons are also reported. The mass of the $\Xi_b^-$ baryon is also measured relative to that of the $\Lambda_b^0$ baryon, from which it is found that \begin{align*} m(\Xi_b^-) &= 5796.70\pm0.39\pm0.15\pm0.17~{\rm MeV}/c^2, \end{align*} where the last uncertainty is due to the precision on the known $\Lambda_b^0$ mass. This result represents the most precise determination of the $\Xi_b^-$ mass.

Absolute Hidden Symmetry in Time and Absolute Asymmetry in Mass and Velocity between a Particle and Its Anti-Particle

In this paper we will the discuss possible hidden symmetry in time and the possible asymmetry in mass and velocity between a particle and its anti-particle. Possible hidden symmetry in time between a particle and its anti-particle manifested in their corresponding possible hidden variables in time, fr and -fr&amp;nbsp; was first discussed in Brodet (2017b). In this paper we will extend the discussion and discuss how the above possible hidden symmetry in time and its corresponding possible symmetry in absolute position, energy and momentum, may yield an asymmetry in mass and velocity of a particle and its corresponding anti-particle. We will deconstruct the particle&amp;rsquo;s and anti-particle&amp;rsquo;s absolute position, into three complex number describing the particle/anti-particle time, velocity and mass. The particle/anti-particle symmetry and asymmetry of the above complex numbers will be discussed in the context of parity violation and the known asymmetry in angular production of particles and anti-particles. Moreover, the possible mass asymmetry will be used to explain the CP violation in the neutral kaon system. Finally, experimental ways to investigate and test the above are presented.

Spin asymmetry in single pion production induced by weak interactions of neutrinos with polarized nucleons

The single pion production (SPP) in the charged-current neutrino (antineutrino) scattering off the polarized nucleon is discussed. The spin asymmetry is predicted within two approaches. The spin polarizations of the target nucleon that are longitudinal and perpendicular to the neutrino momentum are considered. It is shown, in several examples, that information about the SPP dynamics coming from the spin asymmetry is complementary to information obtained from measurements of spin averaged cross section. Indeed, the spin asymmetry is sensitive to the nonresonance background description of the SPP model. For the normal polarization of the target, the spin asymmetry is given by the interference between the resonance and the nonresonance contributions.

Single-spin asymmetry in dihadron production in SIDIS off longitudinally polarized nucleon targets

We study the single longitudinal-spin asymmetry of dihadron production in semi-inclusive deep inelastic scattering process. We consider the collinear picture in which the transverse momentum of the final-state hadron pair is integrated out, such that the $\sin \phi_R$ azimuthal asymmetry arises from the coupling $h_L\, H_{1}^{\sphericalangle}$ as well as the coupling $g_1 \,\widetilde{G}^{\sphericalangle}$. We calculate the unknown twist-3 dihadron fragmentation function $\widetilde{G}^{\sphericalangle}$ using a spectator model which is successful in describing the dihadron production in the unpolarized process. Using the spectator model results for the quark distributions and dihadron fragmentation functions, we estimate the $\sin \phi_R$ asymmetry of dihadron production in SIDIS at the kinematics of COMPASS and compare it with the COMPASS preliminary data. In addition, the prediction on the $\sin \phi_R$ asymmetry at the typical kinematics of the future Electron Ion Collider is also presented. In order to test the reliability of the spectator model estimate, we compare the model result for the distribution $h_L$ with the Wandzura-Wilczek approximation for that distribution, and compare $H_{1}^{\sphericalangle}$ with the existing parametrization. Although the asymmetry is dominated by the $h_L H_{1}^{\sphericalangle}$ term, we find that the contribution from the $g_1\, \widetilde{G}^{\sphericalangle}$ term should also be taken into account in certain kinematical region.

Baryogenesis from the Berry phase

The spontaneous baryogenesis scenario explains how a baryon asymmetry can develop while baryon violating interactions are still in thermal equilibrium. However, generation of the chemical potential from the derivative coupling is dubious since the chemical potential may not appear after the Legendre transformation. The geometric phase (Pancharatnam-Berry phase) results from the geometrical properties of the parameter space of the Hamiltonian, which is calculated from the Berry connection. In this paper, using the formalism of the Berry phase, we show that the chemical potential defined by the Berry connection is consistent with the Legendre transformation. The framework of the Berry phase is useful in explaining the mathematical background of the spontaneous baryogenesis, and also is useful for calculating the asymmetry of the non-thermal particle production in time-dependent backgrounds. Using the formalism, we show that the mechanism can be extended to more complex situations.