Measurement Of Asymmetry Research Articles

Accessing compton form factors at the electron ion collider in China: an impact study on {textbf {Im}} {mathcal E}

We estimate the impact of asymmetry measurements of Deeply Virtual Compton Scattering (DVCS) with transversely polarized proton beam taken at a future Electron Ion Collider in China (EicC) on the extraction of Compton Form Factors (CFFs). The CFFs extracted from an analysis based on artificial neural-network approach are reweighted by means of pseudo-data generated in the expected kinematic region of EicC. We find a remarkable improvement in the extraction of CFF Im {mathcal E}, especially at the range of parton momentum fraction x sim 0.01, thus hinting for a future experimental probe of the parton orbital angular momentum. This work casts a glance at a practical implementation of Bayesian reweighting method on CFFs’ impact study.

Six-month outcomes and patterns of recovery for people with lateropulsion following stroke

Purpose This study investigated the (1) six-month outcomes of individuals with lateropulsion; (2) the relationship between baseline measures (from in-patient hospitalisation) and six-month functional abilities; and (3) recovery patterns for lateropulsion in stroke survivors. Materials and methods Forty-one individuals with lateropulsion participated in this study. Measures of lateropulsion, postural function, and weight-bearing asymmetry in standing were taken initially and fortnightly over eight weeks. Functional independence and walking abilities were assessed at six months post-stroke. Results Compared to individuals with moderate to severe lateropulsion, those with mild lateropulsion achieved higher levels of functional outcome at six months. However, there were a wide range of scores. Baseline lateropulsion severity explained 26% of the variation in functional outcome. A stronger correlation with functional outcome was observed for lateropulsion (−0.526) than function independence at baseline (0.384). For the task of standing with arm support, patterns of asymmetry were divergent at baseline, favouring either the paretic or non-paretic leg. Over the eight-week period, asymmetry moved towards the non-paretic leg and lateropulsion reduced consistently. Conclusions Individuals with lateropulsion can recover from lateropulsion and make meaningful functional gains, including some individuals with more severe lateropulsion. Lateropulsion severity is a key indicator of functional outcome post-stroke. IMPLICATIONS FOR REHABILITATION Individuals with lateropulsion can make significant gains in terms of mobility and functional abilities by six months post-stroke, learning to compensate for their verticality impairment in standing by loading their non-paretic leg. It is important that stroke survivors with lateropulsion, including those with moderate and severe lateropulsion, are provided with adequate rehabilitation to optimise their longer-term mobility and functional abilities. Routine screening of acute stroke survivors for lateropulsion is recommended, given lateropulsion may negatively impact longer-term functional outcomes in stroke survivors. Therapists should carefully analyse the weight-bearing pattern which an individual with lateropulsion adopts in standing and subsequently tailor treatment to target this.

Is idiosyncratic asymmetry priced in commodity futures?

AbstractIn this article, we use a recently introduced asymmetry measure, IE, to measure the idiosyncratic asymmetry of commodity futures returns and find that idiosyncratic asymmetry negatively and significantly predicts commodity futures returns cross sectionally. Furthermore, we find that a long–short trading strategy based on idiosyncratic asymmetry generates significant abnormal returns, which cannot be explained by traditional risk factors in commodity futures and persists up to 12 months. Moreover, idiosyncratic asymmetry appears to be a priced factor in commodity futures with significant risk premium. Finally, we confirm that IE is better at capturing the pricing effect of idiosyncratic asymmetry than the traditional skewness measure.

Measuring galaxy asymmetries in 3D

ABSTRACT One of the commonly used non-parametric morphometric statistics for galaxy profiles and images is the asymmetry statistic. With an eye to current and upcoming large neutral hydrogen (H i) surveys, we develop a 3D version of the asymmetry statistic that can be applied to datacubes. This statistic is more resilient to variations due to the observed geometry than 1D asymmetry measures, and can be successfully applied to lower spatial resolutions (3 – 4 beams across the galaxy major axis) than the 2D statistic. We have also modified the asymmetry definition from an ‘absolute difference’ version to a ‘squared difference’ version that removes much of the bias due to noise contributions for low signal-to-noise observations. Using a suite of mock asymmetric cubes we show that the background-corrected, squared difference 3D asymmetry statistic can be applied to many marginally resolved galaxies in large wide-area H i surveys such as WALLABY on the Australian SKA Pathfinder (ASKAP).

A method for high-precision measuring differential transformer asymmetry.

The differential transformer is an important component in the front-end electronics of high-precision capacitive position sensing circuits, which are widely employed in space inertial sensors and electrostatic accelerometers. The position sensing offset, one of the space inertial sensors' most critical error sources in the performance range, is dominated by the differential transformer asymmetry and requires a high-precision evaluation. This paper proposes a method to assess differential transformers' asymmetry and realize a prototype circuit to test a transformer sample. The results show that the asymmetry measurement precision can achieve 0.6 ppm for the transformer with an asymmetry level of about -278.2 ppm.

First CLAS12 Measurement of Deeply Virtual Compton Scattering Beam-Spin Asymmetries in the Extended Valence Region.

Deeply virtual Compton scattering (DVCS) allows one to probe generalized parton distributions describing the 3D structure of the nucleon. We report the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer with a 10.2 and 10.6GeV electron beam scattering from unpolarized protons. The results greatly extend the Q^{2} and Bjorken-x phase space beyond the existing data in the valence region and provide 1600 new data points measured with unprecedented statistical uncertainty, setting new, tight constraints for future phenomenological studies.

Smooth Metric Adjusted Skew Information Rates

Metric adjusted skew information, induced from quantum Fisher information, is a well-known family of resource measures in the resource theory of asymmetry. However, its asymptotic rates are not valid asymmetry monotone since it has an asymptotic discontinuity. We here introduce a new class of asymmetry measures with the smoothing technique, which we term smooth metric adjusted skew information. We prove that its asymptotic sup- and inf-rates are valid asymptotic measures in the resource theory of asymmetry. Furthermore, it is proven that the smooth metric adjusted skew information rates provide a lower bound for the coherence cost and an upper bound for the distillable coherence.

Measurement of scale-dependent time-reversal asymmetry in biological systems.

Measurement of scale-dependent time-reversal asymmetry in biological systems.

Using Hocker and Burns numerical method to analyze the dispersion properties of a planar waveguide with an exponentially graded-index core layer for s-polarized light

Although not realistic, the theory of step-index waveguide has been discussed in most published works. Electric and magnetic fields can be written as well-known functions such as exponential, sine and cosine functions. However, the index distribution of the most practical waveguides is better described as graded. Despite certain similarities, step-index and graded-index waveguide structures also have considerable differences. The characteristic equation of s-polarized wave propagating in a planar waveguide with an exponentially graded-index thin core layer is examined in this work using the Hocker and Burns numerical approach. This method utilizes the effective index method of analyzing waveguides with 2D confinement. It was efficiently applied to problems of channel waveguides formed by diffusion. The technique depends on finding the phase shift of the curved optical path in the graded index zone as stacked infinite thin layers. Three factors contribute to the total transverse phase shift: (1) film-cladding interface phase delay, (2) film-substrate interface phase delay, and (3) phase delay caused by the zigzag optical path of the guiding film. The findings revealed the following intriguing observations. The dispersion curves of the graded-index waveguide structure are in the normal shape in which the generalized guide index (GeGI) increases with the rise of the normalized frequency. At high values of the normalized frequency, the GeGI displays less dependence on it. The dispersion curves show cut-off thicknesses which increase for higher asymmetry measure values. A comparison between graded-index and step-index waveguide structures is carried out.

Analysis of distributions reveals real differences on dichotic listening scores between left- and right-handers.

About 95% of right-handers and 70% of left-handers have a left-hemispheric specialization for language. Dichotic listening is often used as an indirect measure of this language asymmetry. However, while it reliably produces a right-ear advantage (REA), corresponding to the left-hemispheric specialization of language, it paradoxically often fails to obtain statistical evidence of mean differences between left- and right-handers. We hypothesized that non-normality of the underlying distributions might be in part responsible for the similarities in means. Here, we compare the mean ear advantage scores, and also contrast the distributions at multiple quantiles, in two large independent samples (Ns = 1,358 and 1,042) of right-handers and left-handers. Right-handers had an increased mean REA, and a larger proportion had an REA than in the left-handers. We also found that more left-handers are represented in the left-eared end of the distribution. These data suggest that subtle shifts in the distributions of DL scores for right- and left-handers may be at least partially responsible for the unreliability of significantly reduced mean REA in left-handers.

The gait parameters in patients with Parkinson’s Disease under STN-DBS therapy and associated clinical features

ABSTRACT Objective We aimed to investigate the gait parameters in patients with subthalamic nucleus deep brain stimulation (STN-DBS) therapy using quantitative gait analyses and reveal the associated clinical features. Methods Parkinson’s disease (PD) subjects with STN-DBS who applied to our movement disorders outpatient clinics between December/2021 and March/2022 were enrolled. In addition to the evaluation of the demographic data and the clinical features; clinical scales measuring the freezing of gait (FOG), falls and quality of life were performed. A gait analyzer program was used to perform gait analysis. Results Thirty patients with a mean age of 59.4 ± 8.3 (F/M = 7/23) were enrolled. The comparative analyses between the tremor-dominant and akinetic-rigid (AR) subtype patients showed that the step time asymmetry measures were higher in the AR group. The comparative analyses according to the symptom onset side showed that the step length was smaller in those with left-side symptom onset. The correlation analyses showed that there were correlations between the quality-of-life indexes and FOG questionnaire and falls efficacy scale (FES) scores. Finally, the correlation analyses between clinical scales and gait parameters revealed that there were significant correlations between the FES scores and the step length asymmetry (SLA). Conclusion We found a strong relationship between falls and quality of life indexes of our patients under STN-DBS therapy. In this patient group, particular evaluation of fallings and the follow-up of SLA in gait analysis may constitute important points during the evaluation of patients in routine clinical practice.

First Measurement of the B^{+}→π^{+}π^{0}π^{0} Branching Fraction and CP Asymmetry.

We study B^{+}→π^{+}π^{0}π^{0} using 711 fb^{-1} of data collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We measure an inclusive branching fraction of (19.0±1.5±1.4)×10^{-6} and an inclusive CP asymmetry of (9.2±6.8±0.7)%, where the first uncertainties are statistical and the second are systematic, and a B^{+}→ρ(770)^{+}π^{0} branching fraction of (11.2±1.1±0.9_{-1.6}^{+0.8})×10^{-6}, where the third uncertainty is due to possible interference with B^{+}→ρ(1450)^{+}π^{0}. We present the first observation of a structure around 1 GeV/c^{2} in the π^{0}π^{0} mass spectrum, with a significance of 6.4σ, and measure a branching fraction to be (6.9±0.9±0.6)×10^{-6}. We also report a measurement of local CP asymmetry in this structure.

19 Effects of recombinant equine intra-articular IL-1 on synovial fluid PGE2 and movement asymmetry: A pilot study

Synovitis is a common feature of osteoarthritis (OA). Exogeneous intra-articular inflammatory compounds such as lipopolysaccharide or interleukin 1β (human or equine) produce a convenient, self-limiting, and reversible synovitis in horses, which can be useful to evaluate putative OA interventions. Although biochemical responses to this minimally invasive synovitis model have been described, its effects on functional adaptations in movement remains unclear. The aim of this pilot study was to correlate synovial fluid biochemical responses to intra-articular injection of recombinant equine IL-1b (IL-1) with objective measures of movement asymmetry. Horses (n = 3) randomly received 0, 50 or 75ng reIL-1 in 500μL of sterile saline into the left or right intercarpal joint in a 3-way crossover design, with 50 and 75ng treatments applied to the contralateral carpus and 24 h between treatments. Synovial fluid was collected by aseptic arthrocentesis at 0 (before IL-1 injection), 6, 12 and 24 h after IL-1 injection and analyzed for prostaglandin E2 (PGE2) by ELISA. To quantify movement asymmetry, MinDiff was calculated using withersvertical displacement data (2000 Hz) acquired from an inertial measurement unit (IMU) (Delsys Trigno) during in-hand trot trials at each time point/condition. PGE2 and MinDiff data were analyzed using 2-way repeated measures ANOVA with respect to IL-1 challenge dose and time. Correlations between variables were determined using the Spearman correlation. PGE2 significantly increased at 6 h (314.4 ± 136.4 pg/mL) compared with 0 h (128.0 ± 43.2 pg/mL) following challenge with 75ng IL-1 (P = 0.04). An increase in MinDiff 6 h following 75ng challenge was not significant (P = 0.13). MinDiff and PGE2 peaked simultaneously at 6 h after injection of 75ng IL-1, but the correlation was not significant (P = 0.27). Data from this small pilot study indicate that low intra-articular dose of reIL-1b induces measurable increase in local synovial fluid PGE2, which is a key pro-inflammatory biomarker. Effects on adaptations in gait asymmetry warrant further investigation.

Relationship between patellofemoral joint morphology and chondromalacia patella.

For the normal functioning of the patellofemoral joint (PF), the relationship between the patella and the trochlear groove must be compatible. To investigate the relationship between patellofemoral joint morphology (PFM) and patellar chondromalacia. Overall, 136 knees of patients aged 20-55 years examined between March 2020 and March 2021 were included in this study. In all patients, trochlear sulcus angle, trochlear sulcus depth, trochlear facet asymmetry, patella alta (Insall-Salvati [IS] index), and patellar facet asymmetry were measured. Of these cases, 66 knees with an abnormality detected in any of the measurements for PFM were included in the case group. Moreover, 70 knees with demonstrating normal PFM measurements were included in the control group. The incidence and grade of chondromalacia was higher in the case group than in the control group (P < 0.001). Between the patients with and without chondromalacia trochlear sulcus angle (mean = 138.25° ± 10.02° vs. 132.58° ± 7.24°; P = 0.001), IS index (mean = 1.25 ± 0.21 vs. 1.16 ± 0.15; P = 0.014), patellar facet asymmetry (mean = 0.77 ± 0.09 vs. 0.73 ± 0.12; P = 0.039), trochlear sulcus depth (mean = 5.39 ± 1.42 mm vs. 6.27 ± 1.04 mm; P < 0.001), and trochlear facet asymmetry (mean = 0.67 ± 0.11 vs. 0.71 ± 0.09; P = 0.023) measurements, there was a significant difference. The presence of at least one of the measures indicating pathology in PFM is associated with the presence and severity of chondromalacia.

An algorithmic crowdsourcing approach for atrial fibrillation detection on Apple Watch ECG data

In the present study, we investigated the test-retest stability of resting state alpha asymmetry in 18 children (9 male and 9 female) in a longitudinal design. Children’s resting state brain activation asymmetries were assessed by means of EEG first after 14 months of age, and again a second time at 83 months of age, and frontal (AsymF), temporal (AsymT), and parietal (AsymP) alpha activation asymmetries were calculated. Analyses demonstrate positive relations between frontal asymmetry scores at 14 and 83 months of age. Temporal and parietal asymmetries did not show this stability over time. This finding provides further support for the use of frontal alpha asymmetry measures to investigate processes underlying emotion and motivation in childhood, and its stability over time.

Asymmetry measures for quantification of mechanisms contributing to dynamic stability during stepping-in-place gait.

The goal of this study is to introduce and to motivate the use of new quantitative methods to improve our understanding of mechanisms that contribute to the control of dynamic balance during gait. Dynamic balance refers to the ability to maintain a continuous, oscillating center-of-mass (CoM) motion of the body during gait even though the CoM frequently moves outside of the base of support. We focus on dynamic balance control in the frontal plane or medial-lateral (ML) direction because it is known that active, neurally-mediated control mechanisms are necessary to maintain ML stability. Mechanisms that regulate foot placement on each step and that generate corrective ankle torque during the stance phase of gait are both known to contribute to the generation of corrective actions that contribute to ML stability. Less appreciated is the potential role played by adjustments in step timing when the duration of the stance and/or swing phases of gait can be shortened or lengthened to allow torque due to gravity to act on the body CoM over a shorter or longer time to generate corrective actions. We introduce and define four asymmetry measures that provide normalized indications of the contribution of these different mechanisms to gait stability. These measures are 'step width asymmetry', 'ankle torque asymmetry', 'stance duration asymmetry', and 'swing duration asymmetry'. Asymmetry values are calculated by comparing corresponding biomechanical or temporal gait parameters from adjacent steps. A time of occurrence is assigned to each asymmetry value. An indication that a mechanism is contributing to ML control is obtained by comparing asymmetry values to the ML body motion (CoM angular position and velocity) at the time points associated with the asymmetry measures. Example results are demonstrated with measures obtained during a stepping-in-place (SiP) gait performed on a stance surface that either remained fixed and level or was pseudorandomly tilted to disturb balance in the ML direction. We also demonstrate that the variability of asymmetry measures obtained from 40 individuals during unperturbed, self-paced SiP were highly correlated with corresponding coefficient of variation measures that have previously been shown to be associated with poor balance and fall risk.

Outcome evaluation using an artificial intelligence‐based facial measurement software for facial nerve grafting in head and neck and skull base surgery

Interposition nerve grafting is an indispensable technique for facial nerve reconstruction in head and neck, and skull base surgery. The prognostic factors are inconclusive, partly due to limited objective assessment systems for facial nerve function. This study aimed to apply an artificial intelligence (AI)-based facial asymmetry measurement system to assess facial nerve grafting outcomes. We retrospectively reviewed data of 23 patients who underwent facial nerve grafting between 2011 and 2020. Oral asymmetry and synkinesis severity were measured using AI. Oral movement recovered at 12-18 months postoperatively. Postoperative radiotherapy and a larger number of anastomosed distal stumps were significantly associated with poor and good final oral symmetry, respectively. Synkinesis severity was weakly correlated with the degree of oral movement recovery. Oral function recovered without a strong correlation with synkinesis. Caution should be exercised in facial nerve grafting for cases with postoperative radiotherapy.

Epileptic Tissue Localization through Skewness-Based Functional Connectivity in the High-Frequency Band of Intracranial EEG.

Functional connectivity analysis of intracranial electroencephalography (iEEG) plays an important role in understanding the mechanism of epilepsy and seizure dynamics. However, existing connectivity analysis is only suitable for low-frequency bands below 80 Hz. High-frequency oscillations (HFOs) and high-frequency activity (HFA) in the high-frequency band (80-500 Hz) are thought to be specific biomarkers in epileptic tissue localization. However, the transience in duration and variability of occurrence time and amplitudes of these events pose a challenge for conducting effective connectivity analysis. To deal with this problem, we proposed skewness-based functional connectivity (SFC) in the high-frequency band and explored its utility in epileptic tissue localization and surgical outcome evaluation. SFC comprises three main steps. The first step is the quantitative measurement of amplitude distribution asymmetry between HFOs/HFA and baseline activity. The second step is functional network construction on the basis of rank correlation of asymmetry across time. The third step is connectivity strength extraction from the functional network. Experiments were conducted in two separate datasets which consist of iEEG recordings from 59 patients with drug-resistant epilepsy. Significant difference (p<0.001) in connectivity strength was found between epileptic and non-epileptic tissue. Results were quantified via the receiver operating characteristic curve and the area under the curve (AUC). Compared with low-frequency bands, SFC demonstrated superior performance. With respect to pooled and individual epileptic tissue localization for seizure-free patients, AUCs were 0.66 (95% confidence interval (CI): 0.63-0.69) and (0.63 95% CI 0.56-0.71), respectively. For surgical outcome classification, the AUC was 0.75 (95% CI 0.59-0.85). Therefore, SFC can act as a promising assessment tool in characterizing the epileptic network and potentially provide better treatment options for patients with drug-resistant epilepsy.

Exploring features in chromatographic profiles as a tool for monitoring column performance

In the biopharmaceutical industry, chromatography resins have a finite number of uses before they start to age and degrade, typically due to losses of ligand integrity and/or density. The “health” of a column is predicted and validated by running multiple cycles on representative scale-down models and can be followed by real-time on-going validation during commercial production.Principal Component Analysis (PCA), Partial Least Square (PLS), Similarity Scores and Single One Point-MultiParameter Technique (SOP-MPT) along with machine learning principles were applied to explore the hypothesis that there is predictive capability of latent variables in chromatography absorbance profiles for process performance (step yield) and product quality (aggregates, fragments, host cell proteins (HCP) and DNA, and Protein A ligand).The first stage of this study is described in this paper: a MabSelect SuRe™ chromatography column was cycled with a method to establish the “normal” baseline for process performance and product quality, followed by runs using a harsher NaOH Cleaning in Place (CIP) procedure (with a higher NaOH concentration than that recommended by the vendor) to accelerate resin degradation. The different mathematical analytical tools correlated with resin degradation of the column (reflected in decreasing step yield and binding capacity with increasing running cycle), specifically when using the Wash, Elution and Strip phases of the chromatography method. Monomer, HCP and DNA content were not significantly impacted and therefore a correlation with product quality was inconsequential. Importantly, this work shows proof-of-concept that while more traditional methods of measuring resin integrity such as the height equivalent to a theoretical place (HETP) and Asymmetry (As) measurements could not detect changes in the integrity of the resin, PCA, PLS, Similarity Scores and SOP-MPT (to a lesser extent) applied to the absorbance data were capable of anticipating issues in the chromatography bed by identifying atypical outcomes.

Evidence of A_{CP}(D^0rightarrow pi ^+pi ^-) implies observable CP asymmetry in the D^0rightarrow pi ^0pi ^0 decay

Inspired by the recent measurement of CP asymmetry in the individual mode on LHCb, we study CP asymmetry of the Drightarrow pi pi system in the isospin and topological analysis. The ratio between penguin and tree amplitudes P/(T+C) in the Drightarrow pi pi system is found to be greater than two in most values of the relative strong phase. And D^0rightarrow pi ^0pi ^0 is a potential mode to reveal the CP asymmetry of the order of 10^{-3}, which would be observed by Belle II in the future. The large CP asymmetry in the Drightarrow pi pi system might be understood in the t-channel final-state interaction.