Mass Asymmetry Research Articles

Body composition asymmetry between dominant and non-dominant arms in experienced overhead throwing sports athletes.

Overhead throwing can cause asymmetric physical characteristics induced by certain repeated asymmetric movements. Characterizing these physical properties could provide insights for health promotion, conditioning, and training planning. The status of asymmetric body composition and physical function in overhead throwing sports athletes remains unclear. The aim of this study was to investigate body composition asymmetries in experienced overhead throwing sports athletes. This study included 77 college students classified into three groups, overhead throw sports, non-overhead throw sports, and non-sports experience groups, based on past and current sports activities and years of experience. A body composition analyzer was used to measure body composition variables. The asymmetry in body composition variables between limbs was evaluated using the asymmetry index. Differences between groups were compared using one-way analysis of variance and post-hoc tests. The lean muscle mass asymmetry index of the arms in the overhead throw group was significantly higher than that in the other groups. The dominant arm lean muscle mass in the overhead throw group was significantly higher than that in the other groups. However, the non-dominant arm lean muscle mass in the overhead throw group was significantly higher than that in the non-sports experience group. Overhead throwing sports results in increased muscle mass in the dominant arm and produces asymmetry in muscle mass between the arms. This asymmetry may be induced by repeated and frequent asymmetrical motions. Our findings highlight the importance of characterizing the effect of sports activities on the athletes and may provide insights for conditioning regimens for them.

Numerical and experimental investigation of silo vibration of sulfur storage

PurposeDue to the abundant use of granular materials in chemical industries, it is inevitable to store raw materials and products in bulk in silos. For this reason, much research has been carried out in the field of construction, operation and maintenance of silos. One of the important issues that must be investigated in silos is the behavior of their structure when the materials inside them are unloaded. Structural vibrations and the creation of normal noise usually discharge the granular of material from the silo. Both of phenomena are undesirable due to the problems they can cause to the structure and its surroundings. According to the said issues, this paper aims to investigate the vibration problem of the sulfur storage silo of the first refinery during discharge with the help of measuring experimental vibration data and simulating the silo model.Design/methodology/approachIn the experimental investigation, the main cause of the vibration of the 400-ton silo in the refinery is used. The mass asymmetry phenomenon when the silo is filled is also considered. The experimental results are authenticated by software analysis too.FindingsThe results showed that the natural frequency of the ninth mode is almost equal to the natural frequency of sulfur discharge from the silos and has the largest shape change in the structure and vibration range. It is also concluded that the larger sulfur silo (400 tons) should be prioritized over the smaller sulfur silo (200 tons) in the emptying program, and the 400 tons silo should never be emptied even through the 200 tons silo is empty.Originality/valueAn attempt is made to investigate the issue of vibration in sulfur storage silos in the first refinery of South Pars in the form of experimental investigation and modal analysis.

Quark core-gluon model for heavy hybrid baryons

Besides the ordinary hadrons, quantum chromodynamics (QCD) allows the existence of states in which excitations of the gluonic field can play the role of valence particles, either alone in a glueball, or coupled to quarks in a hybrid. So, hybrid baryons, made of three quarks and a gluon, can exist. Till now, there is no experimental evidence for such exotic hadrons but experimental efforts are being made to search for them at CEBAF Large Acceptance Spectrometer. In this work, a hybrid baryon is considered as a two-body system composed of a color octet three-quark core and a gluon, interacting via a QCD-inspired interaction. A semirelativistic potential model is built in which the dominant interaction is a potential simulating the flux tube confinement, and the Casimir scaling is assumed to link interactions between triplet and octet color sources. This picture is similar to the quark-diquark description for baryons. It is chosen in order to take properly into account the helicity of the gluon. Only cccg and bbbg states are considered because the strong mass asymmetry between the quark core and the gluon is expected to favor the formation of the core. As the results for heavy hybrid baryons seem relevant, we consider this paper as a proof of concept which can be extended for the study of light hybrid baryons. Published by the American Physical Society 2024

Improved semi-empirical formula for cluster radioactivity half-lives

An improved semi-empirical formula for cluster radioactivity half-lives is proposed by incorporating the influences of reduced mass, the blocking effect of unpaired nucleons and mass asymmetry on the basis of the original Tavares formula [Eur. Phys. J. A 49 (2013) 6]. Using this improved semi-empirical formula, the calculated results of the cluster radioactivity half-lives for the daughter nuclei around [Formula: see text]Pb or its neighbors can reproduce the experimental data well with a corresponding root-mean-square deviation [Formula: see text]= 0.570, which proves the feasibility of this formula to calculate cluster radioactivity half-lives in trans-lead nuclei. The accuracy of the improved semi-empirical formula is improved by approximately 37% compared to its predecessor whose the root-mean-square deviation is 0.902. Meanwhile, the influence of deformation effect for cluster radioactivity is also briefly discussed. In addition, we extend this improved semi-empirical formula to predict the half-lives of 51 possible cluster radioactive candidates whose cluster radioactivity are energetically allowed or observed but not yet quantified in NUBASE2020. For comparison, some empirical and/or semi-empirical formulae are also used.

[Translated article] Diagnostic imaging in patients with vertebral compression fractures

Vertebral compression fractures by osteoporosis (OVF) is usually a diagnostic problem and coincides on the age group of metastatic vertebral compression fractures (MVF). Although radiography is the first diagnostic technique, generally is not accurate for depicting demineralization and soft tissue lesions. Magnetic resonance (MRI) is the diagnostic choice. The most relevant signs are intravertebral fluid collection or fluid signal, other vertebral deformities without oedema and older age. Among the most relevant findings for diagnosis MVF are soft tissue mass and pedicle intensity signal asymmetries. However, reproducibility of these findings in clinical practice is moderate.

The Combined Additive Effect of Inter-Limb Muscle Mass Asymmetries and Body Composition Indices on Lower Limb Injuries in Physically Active Young Adults

The Combined Additive Effect of Inter-Limb Muscle Mass Asymmetries and Body Composition Indices on Lower Limb Injuries in Physically Active Young Adults

Progenitor mass and ejecta asymmetry of supernova 2023ixf from nebular spectroscopy

Context. Supernova (SN) 2023ixf was discovered in the galaxy M 101 in May 2023. Its proximity provided the scientific community an extremely valuable opportunity to study the characteristics of the SN and its progenitor. A point source detected on archival images and hydrodynamical modeling of the bolometric light curve have been used to constrain the former star’s properties. There is a significant variation in the published results regarding the initial mass of the progenitor. Nebular spectroscopy can be used to enhance our understanding of the SN and its progenitor. Aims. We determined the SN progenitor mass by studying the first published nebular spectrum, taken 259 days after the explosion. Methods. We analyzed the nebular spectrum taken with GMOS at the Gemini North Telescope. We identified typical emission lines, such as [O I], Hα, and [Ca II], among others. Some species’ line profiles show broad and narrow components, indicating two ejecta velocities and an asymmetric ejecta. We inferred the progenitor mass of SN 2023ixf by comparing its spectra with synthetic spectra and by measuring the forbidden oxygen doublet flux. Results. Based on the flux ratio and the direct comparison with spectra models, the progenitor star of SN 2023ixf had a MZAMS between 12 and 15 M⊙. We find that using the [O I] doublet flux provides a less tight constraint on the progenitor mass. Our results agree with those from hydrodynamical modeling of the early light curve and pre-explosion image estimates that point to a relatively low-mass progenitor.

The Movement of Efimov States in 2n Halo Nucleus: probing the roles of mass asymmetry and short range of interaction

This brief communication presents the results of our work to study the movement of Efimov states in 2-neutron halo nuclei. We discuss the emergence and evolution of Efimov states in to resonances beyond the two-body (n-Core) breakup threshold and also the movement of the Efimov state in a 2-neutron halo nucleus to the region of the so called, Thomas Collapse. We especially, probe the roles of mass asymmetry of the three-body system (n-n-core) and the short range of the n-core interaction in the movement of the Efimov states. The analysis has been carried out within the framework of a three-body model, assuming two-body, non-local, separable potentials for the binary sub-systems, namely, the n-n and n-core systems. The primary motivation has been to scan the parameter space of the range parameter and determine the value(s) for which the system can support the Efimov states. The analysis shows that the value of the range parameter $\beta$ = 5.2$\alpha$ ( $\alpha$ being the energy parameter given in terms of the deuteron binding energy ) produces the realistic three-body binding energy for $^{20}$C and also generates the excited Efimov states. However, as the value of $\beta$ is increased corresponding to decrease in the range of the two-body (n-core) interaction the ground and excited state binding energies increase drastically. In other words, as the range of the two-body interaction tends to zero the system enters the Thomas Collapse region away from the Efimov region.

Investigation of otolith mass asymmetry of Squalius sp. populations sampled from different freshwater sources in Samsun Province (Türkiye)

This research aimed to determine and compare the otolith mass asymmetry (OMA) of Squalius sp. species sampled from ten different freshwater sources in Samsun province. In this context, fish samples obtained from Abdal Stream, Akçay Stream, Engiz Stream, Istavloz Stream, Kaynatma Stream, Mert River, Taşkelik Stream, Terme Stream, Tersakan Stream, Yeşilpınar Stream. The difference between the right and left otoliths were found to be statistically significant in the Istavloz Stream and Tersakan Stream for the asteriscus and in the Abdal Stream for the lapillus (p0.05). This is the first study in which OMA and absolute otolith mass asymmetry of Squalius sp. living in the freshwaters of Samsun province were investigated, and their relationships with fish length were evaluated.

Effect of the charge asymmetry and orbital angular momentum in the entrance channel on the hindrance to complete fusion

The hindrance to complete fusion is studied as a function of the charge asymmetry of colliding nuclei and orbital angular momentum of the collision. The formation and evolution of a dinuclear system (DNS) in the heavy-ion collisions at energies near the Coulomb barrier is calculated in the framework of the DNS model. The DNS evolution is considered as nucleon transfer between its fragments. The results prove that a hindrance at formation of a compound nucleus (CN) is related with the quasifission process, which is breakup of the DNS into products instead to reach the equilibrated state of the CN. The role of the angular momentum in the charge (mass) distribution of the reaction products for the given mass asymmetry of the colliding nuclei has been demonstrated. The results of this work have been compared with the measured data for the quasifission yields in the C12+Pb204 and Ca48+Er168 reactions to show the role of the mass asymmetry of the entrance channel. Published by the American Physical Society 2024

Development of Upper-Extremity Morphological Asymmetries in Male and Female Elite Youth Tennis Players: A Longitudinal Study.

This 2-year longitudinal study examined the development of upper-extremity bone mineral density (BMD), bone mineral content (BMC), and lean mass (LM) asymmetry magnitudes in male and female youth tennis players. Dominant and nondominant upper-extremity BMD, BMC, and LM values of 49 male and 31 female players were measured yearly using dual X-ray absorptiometry. From these values, asymmetry magnitudes were calculated and expressed as a percentage. Maturity offset was estimated using anthropometric measurements. Linear mixed effect models examined the development of BMD, BMC, and LM asymmetry magnitudes according to players' maturity offset, sex, and training volume. Adjusted for sex and training volume, a 1-year increment in maturity offset was associated with a significant increase in BMD (1.3% [2.2%]; P < .001) and BMC (0.6% [2.4%]; P = .011) asymmetry magnitudes. Male players displayed significantly higher LM asymmetry magnitudes (Δ3.2% [8.4%]; P = .002) compared with their female counterparts. Training volume was not significantly associated with asymmetry magnitude development. In contrast to LM, male and female youth tennis players' upper-extremity bones are still responsive to mechanical loading with a significant increase in BMD and BMC asymmetry magnitudes according to maturity offset.

Proton tunneling in the dissociation of H2+ and its asymmetric isotopologues driven by circularly polarized THz laser pulses.

Light-induced deprotonation of molecules is an important process in photochemical reactions. Here, we theoretically investigate the tunneling deprotonation of H2+ and its asymmetric isotopologues driven by circularly polarized THz laser pulses. The quasi-static picture shows that the field-dressed potential barrier is significantly lowered for the deprotonation channel when the mass asymmetry of the diatomic molecule increases. Our numerical simulations demonstrate that when the mass symmetry breaks, the tunneling deprotonation is significantly enhanced and the proton tunneling becomes the dominant dissociation channel in the THz driving fields. In addition, the simulated nuclear momentum distributions show that the emission of the proton is directed by the effective vector potential for the deprotonation channel and, meanwhile, the angular distribution of the emitting proton is affected by the alignment and rotation of the molecule induced by the rotating field.

Vibration Characteristics of Asymmetric Flexible Cantilever Beams Connected to a Central Rigid Body

A satellite with two solar wings can be modeled using a pair of symmetric flexible cantilever beams connected to a central rigid body. Due to certain reasons, the symmetric flexible cantilever beams may be turned into asymmetric ones, which will inevitably influence the vibration properties of the structural system. By changing the structural sizes and adding local mass on one side of the two beams, a structural system with asymmetric mass distribution is obtained and its vibration characteristics are investigated. Hamilton’s principle with the assumed mode method is employed to establish the equation of motion of the asymmetric structural system. The natural frequencies, mode shapes, frequency response curves and displacement time histories of the system are calculated, and they are compared with those of the structural system with a symmetric mass distribution. The correctness and feasibility of the present analytical method are verified by means of the finite element method (FEM) and a vibration experiment. The analytical results show that the mass asymmetry of the two beams leads to the mode localization phenomenon, and the coupling effect between the two beams and the central rigid body is enhanced. The larger the mass asymmetry is and the closer the position of the added local mass to the end of the cantilever beam is, the more obvious of the mode localization phenomenon is and the more obvious of the coupling effect between the two beams and the central rigid body is. The present investigation results are helpful for the dynamic analysis and design of spacecraft structures composed of flexible solar wings and a central rigid body.

The impact of inter-limb leg lean tissue mass asymmetry on stair climb performance in career firefighters

The purpose of this study was to examine the influence of inter-limb leg lean tissue mass (LTM) asymmetry on stair climb (SC) performance in firefighters. Forty-one career firefighters (age = 32.3 ± 8.2 years, body mass = 92.1 ± 18.6 kg, stature = 178.3 ± 7.9 cm) visited the laboratory on one occasion and completed a whole body and leg composition assessment followed by a timed and weighted SC task. Percent body fat (%BF) and leg LTM were determined during a DEXA scan and regional thigh analysis. Asymmetry was assessed by the percent difference between limbs (dominant limb LTM – non-dominant limb LTM)/dominant limb LTM × 100) and a ± 3% cut-off for asymmetry classification. Participants ascended and descended 26 stairs four times as quickly as possible while wearing a weighted (22 kg) vest. Point biserial correlations were used to assess the relationship of inter-limb leg LTM asymmetry and SC performance before and after controlling for age and %BF. Results indicated that inter-limb leg LTM asymmetry was associated with longer SC task time (poorer performance) both before (r = 0.432, P = 0.005) and after (r = 0.502, P = 0.001) controlling for age and %BF. Our findings indicated that inter-limb leg LTM asymmetry negatively impacts firefighter SC performance, which may be improved with appropriate exercise interventions.

Systematic study of two proton radioactivity within the effective liquid drop model

In this study, we investigated two-proton radioactivity using the effective liquid drop model with varying mass asymmetry shapes and effective inertia coefficients (VMAS-EFF). Gaudin’s expression term for Coulomb potential energy is replaced in the current study’s calculation of potential energy. The VMAS-EFF combination predicts the half-life with the lowest standard deviation ( σ =1.03) compared to other models and previous constant mass asymmetry with Werner-inertial Wheeler’s coefficient combinations. The lowest standard deviation value indicates that the VMAS-EFF combination is suitable for reproducing the experimental data. We extended the half-life predictions to another 54 nuclei and compared them with six theoretical model predictions and two empirical formula predictions. The present work also investigated the decay possibilities using quantum tunnelling by computing the driving potential (V-Q) for various states of angular momentum l = 0, 2, 3, and 4. Found that 6Be, 6B, 8C, 12O,15,16Ne, 19Mg, 22Si, 26S, 30Ar 38,39Ti, 40V, 42Cr, 45Fe, 48,49Ni, 54Zn, 58,59,60Ge and 64Se nuclei have a high chance of emission for two protons, while 7B, 10N, 14F, 17Na, 24P, 28Cl,32K, 34Ca, 36,37Sc, 44Mn, 47Co, 52Cu, 56,57,58Ga, 61,62As nuclei have a lower chance for two proton than one proton decay. The computation of separation energy findings agree well with the driving potential findings.

Inter-arm bone mass and size asymmetries in children tennis players are maturity status specific: a 9-month study on the effects of training time across pubertal change and somatic growth

PurposeBone growth with exercise is best assessed by tennis-induced inter-arm asymmetries. Yet, the effects of training and maturation across puberty were unclear. This study explored arm bone growth across 9 months of training in 46 tennis players 7–14 years (25 boys, 21 girls).MethodsBone mineral content (BMC) and bone area (BA) were measured from DXA scans. Pubertal status was assessed by Tanner stage (TS) and somatic growth by maturity offset (MO). Children were grouped as pre- (TS I–I), early (TS I–II), and mid/late pubertal (TS II–III).ResultsTraining time (TT) change in the three groups was 160–170, 190–230, and 200–220 h, respectively. Bone asymmetries were large in all groups (d > 0.8, P < 0.001): 5–18 g (9–21%) and 9–17 g (17–23%) in girls and boys, respectively, for BMC, and 5–15 cm2 (6–13%) and 9–15 cm2 (12–15%) in girls and boys (10–13%), respectively, for BA. BMC and BA change asymmetry peaked at pre-puberty in girls (56%, 46%) and at early puberty in boys (57%, 43%). Asymmetry gains varied with baseline asymmetry (41%) and change in TT (38%) and TS (17%) in BMC, and with baseline asymmetry (58%) and change in MO (17%) and TS (12%) in BA.ConclusionAll bone asymmetries were substantial. Tennis-induced bone gains were higher at pre- to early puberty in girls and at early to mid/late puberty in boys. Training enhanced mostly bone mass and maturity status enhanced mostly bone size; sex was not bone-change modeling impactful. Implications are discussed considering certain limitations.

Fission Fragment Angular Momenta: Generation and Observation

The fission fragment angular momenta can generally be expressed in terms of the six normal modes of rotation for the dinucleus and different models populate those modes to different degrees reflecting the mechanisms involved. For the nucleon exchange mechanism, the characteristic time scales for the various modes are discussed, leading to the expectation that the wriggling mode is fully populated, while twisting is unlikely to play a major role; bending probably has some presence which increases with mass asymmetry. Subsequently it is discussed how information about the fragment spin directions can be determined by observation of E2 emissions in even-even nuclei. It is shown how the yield ratio Y (0°)/Y (90°) in a modern Wilhelmy-type experiment can reveal the degree of twisting, a measurement that could be readily carried out now. Furthermore, with a view towards the future when the required technology has been developed, it is illustrated how the relative role of positive modes (wriggling) and negative modes (bending and twisting) can be determined by measuring the opening angle between two E2 photons whose helicities are also identified.

Minimal numerical ingredients describe chemical microswimmers' 3-D motion.

The underlying mechanisms and physics of catalytic Janus microswimmers is highly complex, requiring details of the associated phoretic fields and the physiochemical properties of catalyst, particle, boundaries, and the fuel used. Therefore, developing a minimal (and more general) model capable of capturing the overall dynamics of these autonomous particles is highly desirable. In the presented work, we demonstrate that a coarse-grained dissipative particle-hydrodynamics model is capable of describing the behaviour of various chemical microswimmer systems. Specifically, we show how a competing balance between hydrodynamic interactions experienced by a squirmer in the presence of a substrate, gravity, and mass and shape asymmetries can reproduce a range of dynamics seen in different experimental systems. We hope that our general model will inspire further synthetic work where various modes of swimmer motion can be encoded via shape and mass during fabrication, helping to realise the still outstanding goal of microswimmers capable of complex 3-D behaviour.

Sub-barrier fusion dynamics in 28,30Si induced reactions with medium mass targets

The state-of-the-art technologies made it possible to reach the realms of fusion between two complex nuclei that offer an opportunity to explore a diverse spectrum of fusion phenomena. In this article, we have reported the influence of positive Q-value neutron transfer (PQNT) channels in fusion dynamics. Significant enhancement in sub-barrier fusion cross section has been observed for the 28Si+158Gd as compared to 30Si+140Ce and other similar systems with nearby mass asymmetry. Current findings include a comparison of the fusion excitation function of multiple systems on a reduced scale. The study sheds light on the influence of PQNT channels and deformation in nuclei on the sub-barrier fusion phenomenon. Further, fusion barrier parameters (barrier height and radius) extracted from the measured data demonstrate a good agreement with the empirical parameterization and proximity potential models.

Otolith Mass Asymmetry of Pampus candidus (Osteichthyes, Stromatidae) from Iraqi Marine Waters

The otolith mass asymmetry of the fish species Pampus candidus was assessed. The findings indicated a significant level of asymmetry comparison with similar studies on other fish species. The level of asymmetry was shown to increase with the size of the fish, where the utmost estimate of the otolith weight irregularity was obtained. The detected otolith asymmetry may be linked to pollutants in the sampling area.