Significant Asymmetry Research Articles

Co-volatility and asymmetric transmission of risks between the global oil and China's futures markets

We construct a multivariate heterogeneous autoregressive model specified with common stochastic volatility and the student-t distribution, the MHAR-CSV-t model, to investigate co-movements and high-frequency volatility transmissions between the WTI futures market and China's stock and commodity futures markets. Additionally, we analyse the time-varying volatility connectedness between these markets. We find that between these markets, the WTI futures market features the most episodes of volatility spikes, particularly since 2014. We find several structural breaks in realised volatility and its decomposition in positive and negative volatility. The results of the time-varying volatility connectedness identify corn, gold, and equity futures as persistent transmitters; the copper futures market as a net receiver; and oil futures as assuming both roles in the spillovers of volatility shocks across markets. We also find significant asymmetries in their volatility decomposition and their spillovers across these markets.

NRAS p.Q61R/K allele load is correlated to different phenotypes of congenital melanocytic naevi.

Congenital melanocytic naevi (CMN) are known to be associated with mosaic NRAS or BRAF variants. However, the exact correlations of the allele load of mosaic variants in CMN with phenotypic characteristics have not been determined. To determine the correlation of variants allele load and different phenotypes of CMN. A panel of genes in the Ras/Raf/MAPK signalling pathway was selected for sequencing in 110 patients with CMN. Correlations between variant allele load and clinical phenotypes, including anatomical localization, projected adult size of the lesion, satellites, subcutaneous nodules, surface rugosity, colour variation and hypertrichosis, were analysed. In addition to the predominant NRAS p.Q61R/K (61.8%) and BRAF p.V600E variants (10%) in patients, we also detected additional variants of NRAS (p.G13R and p.M72fs), BRAF (p.D22N) and MAP2K1 (p.I107fs, p.F209fs, p.Q354H and p.G91_L92insHDQARRLVGDLEHHKPSG). Furthermore, a higher allele load of NRAS p.Q61R/K was found in the trunk and limbs of CMN. It was also found in CMN with larger size, higher colour variation and more significant hypertrichosis, surface rugosity and asymmetry. We discovered more genetic variants of NRAS, BRAF and MAP2K1 and established a correlation between the allele load of NRAS p.Q61R/K and various phenotypes in CMN. The findings of this study potentially facilitate a more accurate and comprehensive classification of CMN in addition to the phenotypic or pathological characteristics used in clinical practice.

The Astrometric Animation of Water Masers toward the Mira Variable BX Cam

AbstractWe report VLBI monitoring observations of the 22 GHz H2O masers toward the Mira variable BX Cam. Data from 37 epochs spanning ∼3 stellar pulsation periods were obtained between May 2018 and June 2021 with a time interval of 3–4 weeks. In particular, the VERA dual-beam system was used to measure the kinematics and parallaxes of the H2O maser features. The obtained parallax, 1.79±0.08 mas, is consistent with Gaia EDR3 and previous VLBI measurements. The position of the central star was estimated relied on Gaia EDR3 data and the center position of the 43 GHz SiO maser ring imaged with KVN. Analysis of the 3D maser kinematics revealed an expanding circumstellar envelope with a velocity of 13±4 km s−1 and significant spatial and velocity asymmetries. The H2O maser animation achieved by our dense monitoring program manifests the propagation of shock waves in the circumstellar envelope of BX Cam.

Compliments and Compliment Responses among Palestinian EFL University Learners: A Sociolinguistic Study

This study investigates compliments and compliment responses from a sociolinguistic perspective as realized by forty Palestinian EFL university learners. The investigation focused on identifying how the participants perform compliments and compliment responses in English. Moreover, it addressed the asymmetries in this field among male and female participants. The researchers created a discourse completion task (DCT) to collect data. The collected data were analyzed based on the analytical framework of Yuan (2002) of compliment strategies and the analytical framework of Herbert (1990) of compliment responses strategies. The findings of the study show that Palestinian EFL university learners tend to perform explicit compliments more than other compliment strategies. The learners also tend to accept compliments more than reject them. Besides, there are no significant gender asymmetries among Palestinian EFL university learners in terms of how they perform compliments and compliment responses. Finally, the findings reveal that social status does not affect the way Palestinian EFL university learners express and respond to compliments. Keywords: Compliment, Compliment Responses, DCT, Compliment Strategies, Gender, Social Status.

Lower Extremity Kinematic Waveform Analysis During a Single Leg Drop Task - Including a Single Subject Design.

Lower limb asymmetries may be associated with increased injury risk in an active female population. However, an appropriate method for determining these asymmetries has not been established. The purpose of the present study was to examine the single leg drop landing (SLD) kinematic waveforms of female recreational athletes for the pelvis, hip, and knee using statistical parametric mapping (SPM). It was hypothesized that individual bilateral differences would be masked by the group analysis. Descriptive Laboratory Study. The current study examined the sagittal and frontal plane pelvis, hip, and knee kinematics of nine physically active females during a SLD. To better elucidate whether asymmetries were present between right and left limbs throughout the landing phase, data were analyzed with SPM. The time-series data were comprised from initial contact to the bottom of the landing. A single subject design was also included to account for potential interindividual variability. At the group level there were no statistical differences between the right and left limbs of participants for all variables. The single subject design yielded at least two significant asymmetries for all participants. Six out of the nine participants had bilateral differences for all six kinematic time-series. The lack of significant differences at the group level may have been masked by movement variability amongst participants. For example, when considering participants with significant differences for hip flexion, four participants had greater values on the left limb and three on the right. A similar observation was made for knee flexion where three participants had significantly greater kinematic values on the left versus four on the right. Until a method is developed to adequately dichotomize lower extremities during the SLD task, a single subject design strategy be used with group analysis when making bilateral comparisons. 3.

Low and asymmetrical hippocampal glutamate levels in healthy older adults

AbstractBackgroundGlutamate (Glu) is a critical molecule in cellular metabolism and the most abundant excitatory neurotransmitter in the brain. Glutamate dysfunction is common in neurodegenerative disorders—patients with Alzheimer’s disease (AD) have lower hippocampal glutamate—and likely contributes to age‐related declines in cognitive functioning. The extant literature on age‐related changes in brain Glu is small and all studies have employed proton spectroscopy. Thus, in this investigation we use a novel 7T magnetic resonanace imaging technique, Glutamate Chemical Exchange Saturation Transfer (GluCEST), to compare bilateral hippocampal brain Glu in between healthy old and young adults.MethodHippocampal GluCEST data were acquired from 14 healthy older adults [HOA; age: 71 (+/‐3)] and 10 young healthy adults [HYA; age: 21 (+/‐3)] using a Siemens 7T Terra. GluCEST data was acquired in axial slice positioned through bilateral hippocampus. Associations between MoCA scores and bilateral hippocampal GluCEST levels were investigated.ResultBilateral glutamate levels were 7% higher HYA as compared to HOA. HOA showed significant asymmetry (Left>Right) within the hippocampus while GluCEST in HYA were equivalent across hemisphere (t(22)=2.37, p<0.03). Within HOA, higher left hippocampal GluCEST levels were associated with higher performance on the MoCA [r(13)=0.55, p<0.04].ConclusionGluCEST appears to be a marker of aging‐related neurological and cognitive change. The present findings are similar to previous findings in AD (Graff‐Radford et al., 2013) Moreover, the left‐right asymmetry in GluCEST aligns with recent translational studies indicating a left‐right dissociation in long‐term memory function, which may be partially mediated by asymmetries in glutamate receptor content (Shipton et al., 2014). This preliminary study is the first to compare GluCEST levels in young and older adults and is the first step towards elucidate age‐related trajectories of glutamatergic alterations and their relationship to clinical and cognitive phenotypes.

Two-channel optimal discrete law of control of spacecraft with aerodynamic and inertial asymmetry during descent in Mars atmosphere

At present, spacecraft attitude stability is of great importance for both state and private space companies and agencies. In this paper, we consider a mathematical model describing perturbed motion of spacecraft as a rigid body with significant aerodynamic and inertial asymmetry relative to the center of mass in the rarefied atmosphere of Mars. The aim of this work is to obtain an approximate discrete optimized law of controlling the spacecraft attitude using Bellman's dynamic programming and averaging methods. Discrete systems of equations used in the work were solved using the Z-transform method. The reliability of the obtained control laws was confirmed by the results of numerical integration by the numerical Euler method.

Condylar Asymmetry in Children with Unilateral Posterior Crossbite Malocclusion: A Comparative Cross-Sectional Study.

Unilateral posterior crossbite (UXB) is a common, severely asymmetric malocclusion, characterized by maxillary hypoplasia and masticatory dysfunction. The aim of this research is to evaluate the asymmetry of mandibular condyles and rami in children with UXB. This comparative cross-sectional study included 33 children with UXB (girls = 15, boys = 18; mean age ± SD = 8.0 ± 1.3 years.months]) and 33 age- and gender-matched controls (girls = 15, boys = 18; mean age ± SD = 8.4 ± 1.3 years.months]). Pre-treatment OPGs were analyzed by comparing the height of condyles and rami between the sides using the method by Habets et al. (1988); the result was considered significant if the degree of asymmetry was >6%. Children with UXB showed a significantly increased asymmetry of mandibular condyles (mean ± SD = 10.7% ± 9, p < 0.001), but not of rami (mean ± SD = 1.9% ± 2.3), compared to controls. The rami did not show significant asymmetry in either group. The presence of an increased condylar asymmetry index in a developing patient with unilateral posterior crossbite is a sign of altered skeletal growth and should be considered in the diagnostic process and treatment plan.

Characteristics of Strong Ground Motions from Four M S ≥ 5.0 Earthquakes in the 2021 Yangbi, Southwest China, Seismic Sequence

ABSTRACT A seismic sequence has struck the Yangbi county, west part of Yunnan Province in southwest China since May 18, 2021 . This region experienced the strongest ground shakings on the night of 21 May with the successive occurrence of four earthquakes with M S ≥5.0 in a short time and more small earthquakes. Large numbers of strong-motion recordings obtained in the four earthquakes with M S ≥5.0 (i.e. the M S 5.6 foreshock, the M S 6.4 mainshock, the M S 5.0 and M S 5.2 aftershocks) were analyzed in detail to characterize the source effects, distance decay, etc. The velocity pulse-like waveform at near-source station 53YBX and the significant asymmetry of distance decay along the SSE-NNW direction (i.e. much slower toward the SSE) in the M S 6.4 mainshock seem to hint the occurrence of the asymmetrical source rupture. The source rupture directivity for the four events were investigated by fitting the azimuth-dependent residuals of the PGAs. The M S 6.4 mainshock is characterized by the significantly asymmetrical bilateral rupture propagation, predominantly in the SSE direction with a rupture velocity of about 2.24 km/s. The PGA and PSAs from the four earthquakes were further compared with the predicted medians of the ASK14 and CY14 prediction models for global shallow crustal earthquakes. The negative inter-events residuals reflect the weaker source contributions of the Yangbi events to ground motions. The source contributions to short-period ground motions approximately show the dependence on earthquake type, that is, M S 5.6 foreshock > M S 6.4 mainshock > M S 5.2 aftershock, consistent with the dependence of stress drop on earthquake type. We further noted that the inter-events values for the M S 5.0 aftershock are far below those for the M S 5.2 aftershock. This may be attributed to the differences in the spatial and temporal distance to the mainshock, that is, weak source contributions from the close aftershocks to the mainshock. The values of adjustment coefficient Δc 3 are almost positive, indicating the weaker anelastic attenuations in the study region. Finally, we also found that the distance scaling of significant duration can be well described by both empirical models (AS16 model for predicting significant duration and the BT14 model for empirically illustrating the ground-motion path duration).

A refined Moho depth model from a joint analysis of gravity and seismic data of the South China Sea basin and its tectonic implications

As a typical marginal sea in the western Pacific, the South China Sea (SCS) has experienced a complex evolutionary process, and mapping its Moho depth can help us understand the accretion process of the oceanic crust. In this study, we present a refined Moho depth model in the SCS based on gravity inversion constrained by seismic data. For a more reliable gravity-derived Moho depth, an improved sediment thickness grid is constructed from a large volume of seismic reflection/refraction data. The gravity-derived Moho depths are in good agreement with the seismically determined ones, with the majority of differences falling within ±2.5 km. Our results reveal a significant crustal thickness asymmetry across the mid-ocean ridge of the East Sub-basin of the SCS basin since the ridge jump at 23.6 Ma. We attribute this asymmetry to higher residual mantle temperature and more magma supply north of the spreading center. The higher mantle temperature to the north is evidenced by the shallower Curie depth estimated from magnetic anomalies than to the south of the spreading ridge.

Sustainability, justice and equity in food systems: Ideas and proposals in dispute in Brazil

The impacts of food systems on climate change are of growing concern as meat consumption and the soy-meat complex expand. This article explores contrasting ideas, proposals and narratives in the Brazilian context with its significant power asymmetries and identifies two broad discursive repertoires voiced by the private sector, civil society and government to differently address issues of food and environmental justice, social equity and climate change. The influence of these repertoires on public policies can induce or hinder just transitions in food systems. Documents from 2008 to 2021 are analyzed, mainly focusing on multi-scale food systems, dimensions of justice and corporate political action. Contrasting perspectives on the drivers of inequalities and sustainability are also presented, along with respective proposals ranging from paradigm shifts in food systems to topical solutions based on private mechanisms.

Spatiotemporal Atlas of the Fetal Brain Depicts Cortical Developmental Gradient.

The fetal brains experience rapid and complex development in utero during the second and third trimesters. In utero MRI of the fetal brain in this period enables us to quantify normal fetal brain development in the spatiotemporal domain. In this study, we established a high-quality spatiotemporal atlas between 23 and 38 weeks gestational age (GA) from 90 healthy Chinese human fetuses of both sexes using a pairwise and groupwise registration pipeline. We quantified the fetal cortical morphology indices and characterized their spatiotemporal developmental pattern. The cortical thickness exhibited a biphasic pattern that first increased and then decreased; the curvature fitted well into the Gompertz growth model; sulcal depth increased linearly, while surface area expanded exponentially. The cortical thickness and curvature trajectories consistently pointed to a characteristic time point around GA of 31 weeks. The characteristic GA and growth rate obtained from individual cortical regions suggested a central-to-peripheral developmental gradient, with the earliest development in the parietal lobe, and we also observed a superior-to-inferior gradient within the temporal lobe. These findings may be linked to biophysical events, such as dendritic arborization and thalamocortical fibers ingrowth. The proposed atlas was also compared with an existing fetal atlas from a white/mixed population. Finally, we examined the structural asymmetry of the fetal brains and found extensive asymmetry that dynamically changed with development. The current study depicted a comprehensive profile of fetal cortical development, and the established atlas could be used as a normative reference for neurodevelopmental and diagnostic purposes, especially in the Chinese population.SIGNIFICANCE STATEMENT We generated a high-quality 4D spatiotemporal atlas of the normal fetal brain development from 23 to 38 gestational weeks in a Chinese population and characterized the spatiotemporal developmental pattern of cortical morphology. According to the cortical development trajectories, the fetal cerebral cortex development follows a central-to-peripheral developmental gradient that may be related to the underlying cellular events. The majority of cortical regions already exhibit significant asymmetry during the fetal period.

Asymmetric Response of Sea Surface Salinity to Extreme Positive and Negative Indian Ocean Dipole in the Southern Tropical Indian Ocean

AbstractBased on the Argo and multi‐satellite observations, this study investigates the asymmetric response of sea surface salinity (SSS) to two extreme positive and negative Indian Ocean Dipole (IOD) events in the southern tropical Indian Ocean (TIO). During positive IOD events, the easterly wind anomalies trigger zonal freshwater advection along the equator, decreasing SSS, while cold sea surface temperature (SST) depress the convective precipitation in the southeastern TIO (SETIO), increasing the SSS. Contrast SSS anomalies along the equator and in the SETIO show opposite phases during positive and negative IOD events. These SSS anomalies have enhanced in recent years, reaching the strongest in the extreme negative IOD in 2016 and positive IOD in 2019. The case study shows that positive SSS anomalies occurred in the southern TIO during both positive and negative IOD events in 2016 and 2019, suggesting significant asymmetry in SSS. Analysis of the mixed layer salinity budget shows that the local precipitation and the entrainment associated with the upwelling Rossby waves played an essential role in the SSS increase in 2016, while the decreased precipitation and horizontal advection caused by the westward South Equatorial Current contributed to the SSS increase in 2019. Further analyses suggest that SSS response is more sensitive to thermocline shoaling than deepening, and SSS response to precipitation is greater at shallower mixed layer than at deeper ones, which is the main reason for the asymmetric response of the SSS to negative and positive IOD events.

Supportive, Fitted, and Comfortable Bras for Individuals with Atypical Breast Shape/Size: Review of the Challenges and Proposed Roadmap

Individuals with atypical breast shape/size often find it quite challenging to obtain a comfortable, supportive, and fitted bra off-the-shelf. They include people with very large breasts, who have significant breast asymmetry, and/or have undergone mastectomy or mammoplasty. This paper provides insights in their challenges and attempts to fill the gap in terms of critical review of the current state of knowledge around the topic of bras. Poor and ill fitted bras are associated with breast, chest and shoulder pain, embarrassment, and an overall reduction in quality of life among others. Building upon the advantages and limitations of solutions to improve the fit, support and comfort of bras found in the literature, this paper proposes strategies to solve these challenges. As the problem is multidisciplinary, a human-centered interdisciplinary approach is key to ensure that all aspects are considered at all stages of the process. A modular design allows selecting the fabric characteristics based on the requirements of each bra part. In terms of materials, stretch woven fabrics offer a large potential in the production of bras to enhance the support provided by areas such as the under band and back panels. Bespoke manufacturing takes into account the specificities of each individual. The road map proposed here will contribute to enhance the quality of life of individuals with atypical breast shape/size.

An incidental radiolucent lesion involving the angle of the mandible

A 58-year-old white female was referred to the oral and maxillofacial surgeon for evaluation of a soft tissue lesion on the left lower lip with a clinical impression of mucocele. At the time of the appointment, the lesion had significantly decreased in size. The clinical diagnosis of a resolving mucocele was established, and the patient decided to monitor the lesion. Extraoral and intraoral examination failed to reveal any significant asymmetry or mass effect besides the referred area on the lower lip.

Damage evolution mechanism and deformation failure properties of a roadway in deep inclined rock strata

Underground engineering excavation can lead to sharp stress change in the rock mass around the excavation surface, which can cause different degrees of rock damage, ultimately resulting in instability failure. Especially for inclined stratified rock mass that is ubiquitous on Earth, the evolution characteristics, development law and formation mechanism of an excavation damage zone are highly complicated due to its significant asymmetry. Therefore, the evolution mechanism and deformation failure properties of a typical deep roadway in inclined rock strata in Jinchuan Mine of China were investigated by means of a field investigation, theoretical analysis, similar model test and numerical simulation. The results indicate that the deformation failure of a roadway in deep inclined rock strata shows a prominent asymmetry and time sequence. Ground stress has a great influence on the development mode and evolution characteristics of the surrounding rock damage zone. However, as a deep ground stress environment tends to cause hydrostatic pressure, its leading role is gradually weakened. The structural planes control the damage evolution mode of the surrounding rock, an excavation damage zone developed parallel to the interface is formed around the goaf, and an overall instability of the roadway is caused by the sliding of surrounding rock along the structural plane. The conclusions of this study should provide a theoretical reference and demonstrate the key technologies that support underground engineering under similar geological conditions.

Microscopic Origin of the Effective Spin-Spin Interaction in a Semiconductor Quantum Dot Ensemble

We present a microscopic model for a singly charged quantum dot (QD) ensemble to reveal the origin of the long-range effective interaction between the electron spins in the QDs. Wilson's numerical renormalization group (NRG) is used to calculate the magnitude and the spatial dependency of the effective spin-spin interaction mediated by the growth-induced wetting layer. Surprisingly, we found an antiferromagnetic Heisenberg coupling for very short inter-QD distances that is caused by the significant particle-hole asymmetry of the wetting layer band at very low filling. Using the NRG results obtained from realistic parameters as input for a semiclassical simulation for a large QD ensemble, we demonstrate that the experimentally reported phase shifts in the coherent spin dynamics between single- and two-color laser pumping can be reproduced by our model, solving a long-standing open problem of the microscopic origin of the inter-QD electron spin-spin interaction.

Oblique and rippled heliosphere structures from the Interstellar Boundary Explorer

Past analysis has shown that the heliosphere structure can be deduced from correlations between long-scale solar wind pressure evolution and energetic neutral atom emissions. However, this required spatial and temporal averaging that smoothed out small or dynamic features of the heliosphere. In late 2014, the solar wind dynamic pressure increased by roughly 50% over a period of 6 months, causing a time and directional-dependent rise in around 2–6 keV energetic neutral atom fluxes from the heliosphere observed by the Interstellar Boundary Explorer. Here, we use the 2014 pressure enhancement to provide a simultaneous derivation of the three-dimensional heliospheric termination shock (HTS) and heliopause (HP) distances at high resolution from Interstellar Boundary Explorer measurements. The analysis reveals rippled HTS and HP surfaces that are oblique with respect to the local interstellar medium upwind direction, with significant asymmetries in the heliosphere structure compared to steady-state heliosphere models. We estimate that the heliosphere boundaries contain roughly ten astronomical unit-sized spatial variations, with slightly larger variations on the HTS surface than the HP and a large-scale, southwards-directed obliquity of the surfaces in the meridional plane. Comparisons of the derived HTS and HP distances with Voyager observations indicate substantial differences in the heliosphere boundaries in the northern versus southern hemispheres and their motion over time.

The Contribution of Local Agents and Citizens to Sustainable Development: The Portuguese Experience

The achievement of the 2030 Agenda implies a shared responsibility in the implementation of the Sustainable Development Goals (SDGs). Local government, in particular municipalities, is closer to citizens and, therefore, better placed to respond to the needs of each region. This study intends to explore initiatives promoted by civil society, businesses, and local organizations in the context of each municipality in Portugal to address the sustainable development goals established in the 2030 Agenda. It adopts mixed methods to quantify the impact of these initiatives in the territories and qualitatively explores the inherent characteristics associated with each project. The findings show that there are significant asymmetries in the number of projects in the Portuguese regions and that there is a moderately positive correlation between the number of projects and the municipality’s population density and GDP. It was also found that the projects focus mainly on areas such as SDG1, SDG1, SDG11, and SDG13. The projects are mainly characterized by offering platforms for collaborative work among the various stakeholders, seeking to meet the challenges of combating social exclusion, and supporting environmental education. Above all, this study offers implications for local agents to work in networks and establish synergies between projects that may lead to greater territorial coverage and contribute to reducing the socioeconomic asymmetries that exist in the country.

The use of thermal imaging for monitoring the training progress of professional male sweep rowers

This study assesses the thermal profile of the skin in highly trained rowers and investigates the relationship between resting skin temperature (Ts) and the muscle peak torque (PT) measured in statics at the beginning (autumn) and the end (spring) of the preparatory period. Ten professional male sweep rowers, members of the Polish national rowing team, were investigated. A thermal imaging camera was used to analyze the Ts. The PT of the muscles involved in the rowing cycle were measured isometrically. No significant temperature asymmetries were found, except in front of arms after exercise in the spring (p = 0.0228). In contrast, the PT test in the autumn confirmed the significant asymmetry of the knee joint extensors (p = 0.0192). In spring compared to autumn, Ts in many areas of the body were slightly higher, as was PT of underlying muscles. Significant correlations between resting Ts and PT of the underlying muscles were found. Thermal imaging makes it possible to observe changes in skin temperature and symmetry before and after exercise. At this stage, it does not appear to be a method that, without supporting of other methods such as those assessing muscle function, will allow monitoring of training progress.