Lower Moments Research Articles

Mass transfer kinetics and quality evaluation of tomato seed oil extracted using emerging technologies

The Present study was conducted to extract tomato seed oil using emerging technologies which include moderate electric field (MEF), low temperature microwave (MW), radio-frequency (RF), power ultrasound (US) and combined low temperature microwave-power ultrasound (MWUS) at different solid to liquid (S/L) ratio and power level. A green solvent (ethanol: ethyl acetate) was used to extract the oil from tomato seed and a mass transfer kinetic study was studied to find the extraction kinetics and effect of different treatments. MWUS assisted extracted oil was observed to have the highest extraction yield (23.07%) as well as the best quality of oil extracted. The extracted oil using MWUS treatment was mainly composed of PUFA (Linoleic acid), MUFA (Oleic acid) and Stearic acid. Low temperature microwave-ultrasound assisted extraction (MUAE) increased the linoleic, stearic and oleic acid content by 30.91, 5.16 and 7.29% respectively in tomato seed oil composition compared to the conventional Soxhlet extraction (SXE) method. Industrial relevanceThe novel ‘Low temperature microwave-ultrasound assisted extraction (MUAE)’ technology presents a promising result combination of emerging technology for the extraction of oil. The impact of low temperature dipole moment of microwave followed by low intensity ultrasound cavitation leads to the breakdown of the tomato seed matrix. Further, this combination improved the extraction yield although the solvent used very lower solubility compared to conventional solvents. The quality of the extracted oil following MUAE technology was found to be much better than conventional extraction. Hence this combination presents a good scope for application in the food industry, with good commercial value and being environmentally friendly makes it more acceptable.

Sex difference in effect of ankle landing biomechanics in sagittal plane on knee valgus moment during single-leg landing

Ankle landing strategies affects the biomechanical characteristics of the knee joint, especially knee frontal plane loading. However, no studies have investigated whether the association between ankle landing biomechanics in sagittal plane and the knee frontal plane loading differs between sexes. The purpose of this study was to examine whether there is a sex difference in the effect of ankle plantar flexion at the contact angle, ankle range of motion (ROM), and ankle plantar flexion moment on knee valgus loading during single-leg landing. Twenty-five females and twenty-four males performed a single-leg landing. Joint kinematics and kinetics of the lower extremities were measured. The relationship between ankle biomechanics in the sagittal plane (ankle plantar flexion angle at contact, ROM, and peak ankle plantar flexion moment) and peak knee valgus moment were analyzed. In males, the larger ankle plantarflexion angle at contact and ROM were significantly associated with lower peak knee valgus moment. In addition, in males only, a greater peak ankle plantar flexion moment was significantly associated with a lower peak knee valgus moment and greater peak ankle inversion moment. Altering ankle landing strategies in the sagittal plane during single-leg landing may reduce the knee valgus moment, which is one of risk factors for anterior cruciate ligament injury, in males only.

Kinematic and Kinetic Gait Characteristics in People with Patellofemoral Pain: A Systematic Review and Meta-analysis.

Patellofemoral pain (PFP) is a prevalent knee condition with many proposed biomechanically orientated etiological factors and treatments. We aimed to systematically review and synthesize the evidence for biomechanical variables (spatiotemporal, kinematic, kinetic) during walking and running in people with PFP compared with pain-free controls, and determine if biomechanical variables contribute to the development of PFP. Systematic review and meta-analysis. We searched Medline, CINAHL, SPORTDiscus, Embase, and Web of Science from inception to October 2021. All study designs (prospective, case-control [± interventional component, provided pre-intervention data were reported for both groups], cross-sectional) comparing spatiotemporal, kinematic, and/or kinetic variables during walking and/or running between people with and without PFP. We identified 55 studies involving 1300 people with PFP and 1393 pain-free controls. Overall pooled analysis identified that people with PFP had slower gait velocity [moderate evidence, standardized mean difference (SMD) -0.50, 95% confidence interval (CI) -0.72, -0.27], lower cadence (limited evidence, SMD -0.43, 95% CI -0.74, -0.12), and shorter stride length (limited evidence, SMD -0.46, 95% CI -0.80, -0.12). People with PFP also had greater peak contralateral pelvic drop (moderate evidence, SMD -0.46, 95% CI -0.90, -0.03), smaller peak knee flexion angles (moderate evidence, SMD -0.30, 95% CI -0.52, -0.08), and smaller peak knee extension moments (limited evidence, SMD -0.41, 95% CI -0.75, -0.07) compared with controls. Females with PFP had greater peak hip flexion (moderate evidence, SMD 0.83, 95% CI 0.30, 1.36) and rearfoot eversion (limited evidence, SMD 0.59, 95% CI 0.03, 1.14) angles compared to pain-free females. No significant between-group differences were identified for all other biomechanical variables. Data pooling was not possible for prospective studies. A limited number of biomechanical differences exist when comparing people with and without PFP, mostly characterized by small-to-moderate effect sizes. People with PFP ambulate slower, with lower cadence and a shortened stride length, greater contralateral pelvic drop, and lower knee flexion angles and knee extension moments. It is unclear whether these features are present prior to PFP onset or occur as pain-compensatory movement strategies given the lack of prospective data. PROSPERO # CRD42019080241.

Magnetophoretically enhanced separation of particles in engine oil filters

This study conceptualizes the use of magnetic fields to improve the performance of engine oil filters for the first time. Experimental analysis of the particles extracted from multiple engine oil filters indicates the sensitivity of a large portion of them to external magnetic fields indicating the capability of the magnetophoresis to separate particles. The effect of several parameters, including flow velocity, particle size, oil viscosity, magnetic field intensity, and dipole arrangement on the capture efficiency of the magnetic field is numerically investigated. The capture efficiency of the magnetic field substantially increases with increasing its intensity. Increasing the particle diameter at a fixed particle density or increasing the particle density at a fixed diameter increases the capture efficiency. Also, increasing the oil viscosity generally decreases the magnetic field capture efficiency. Using more dipole moments, up to an optimum number, and placing them equidistantly around the filter raises the capture efficiency significantly. The efficiency rise is higher at lower magnetic dipole moments. The maximum efficiency increase obtained by increasing the dipole number is 20%. When the overall dipole moment is fixed, a similar trend is observed for the capture efficiency, although with a different optimum dipole number. Finally, employing a compound magnetic field generated by means of a magnetic belt to assist particle separation in oil filters is proven to be a promising idea.

DOA Tracking With Nested Arrays via an Improved Multisource Multi-Bernoulli Filtering in the Presence of Impulsive Noise

Traditional DOA tracking algorithms have poor performance when considering source time-varying and impulsive noise interference. To address these issues, an improved multisource multi-Bernoulli (IMSMB) particle filtering algorithm based on phased fractional lower order moment is proposed. In the IMSMB algorithm, an unscented transform method is used to operate the surviving particles, which increases the diversity of resampling particles. Moreover, the proposed method is extended to nested array to improve tracking accuracy. Simulation results verify the superiority of the proposed method compared to the existing DOA tracking algorithm.

Dataset of lower extremity joint angles, moments and forces in distance running

This study presents a database of joint angles, moments, and forces of the lower extremity from distance running at a submaximal speed in recreational runners. Twenty recreational runners participated in two experimental sessions, specifically pre and post a 5k treadmill run, with a synchronous collection of markers trajectories and ground reaction forces for both limbs in walking and running trials. The raw data in C3D files could be used for musculoskeletal modelling. Extra datasets of joint angles, moments, and forces are presented ready-for-use in MAT files, which could be as reference for study of biomechanical alterations from distance running. Applying advanced data processing techniques (Machine Learning algorithms) to these datasets (C3D&MAT), such as Principal Component Analysis, could extract key features of variation, thus potentially being applied for correlation with accelerometric and gyroscope parameters from wearable sensors during field running. Dataset of multi-segmental foot could be another contribution for the investigation of foot complex biomechanics from distance running. The dataset from Asian males may also be used for population-based studies of running biomechanics.

Influence of body mass index and anterior cruciate ligament reconstruction on gait biomechanics.

Body mass index (BMI) and history of anterior cruciate ligament reconstruction (ACLR) independently influence gait biomechanics and knee osteoarthritis risk, but the interaction between these factors is unclear. The purpose of this study was to compare gait biomechanics between individuals with and without ACLR, and with and without overweight/obesity. We examined 104 individuals divided into four groups: with and without ACLR, and with low or high BMI (n = 26 per group). Three-dimensional gait biomechanics were evaluated at preferred speed. The peak vertical ground reaction force, knee flexion angle and excursion, external knee flexion moment, and external knee adduction moment were extracted for analysis. Gait features were compared between groups using 2 (with and without overweight/obesity) × 2 (with and without ACLR) analysis of variance. Primary findings indicated that those with ACLR and high BMI had a larger external knee adduction moment compared with those with low BMI and with (p = 0.004) and without ACLR (p = 0.005), and compared with those without ACLR and high BMI (p = 0.001). The main effects of ACLR and BMI group were found for the knee flexion moment, and those with ACLR and with high BMI had lower knee flexion moments compared with those without ACLR (p = 0.031) and with low BMI (p = 0.021), respectively. Data suggest that individuals with ACLR and high BMI may benefit from additional intervention targeting the knee adduction moment. Moreover, lower external knee flexion moments in those with high BMI and ACLR were consistent, but high BMI did not exacerbate deficits in the knee flexion moment in those with ACLR. [Correction added on 9 November 2022, after first online publication: In the preceding sentence, for clarity, the words "reductions in the lower" was removed from the initial sentence to read "Moreover, lower external knee flexion moments".].

Matching upper and lower moment bounds for a large class of stochastic PDEs driven by general space-time Gaussian noises

Matching upper and lower moment bounds for a large class of stochastic PDEs driven by general space-time Gaussian noises

Comparison of Lower Extremity Joint Moment and Power Estimated by Markerless and Marker-Based Systems during Treadmill Running.

Background: Markerless (ML) motion capture systems have recently become available for biomechanics applications. Evidence has indicated the potential feasibility of using an ML system to analyze lower extremity kinematics. However, no research has examined ML systems’ estimation of the lower extremity joint moments and powers. This study aimed to compare lower extremity joint moments and powers estimated by marker-based (MB) and ML motion capture systems. Methods: Sixteen volunteers ran on a treadmill for 120 s at 3.58 m/s. The kinematic data were simultaneously recorded by 8 infrared cameras and 8 high-resolution video cameras. The force data were recorded via an instrumented treadmill. Results: Greater peak magnitudes for hip extension and flexion moments, knee flexion moment, and ankle plantarflexion moment, along with their joint powers, were observed in the ML system compared to an MB system (p < 0.0001). For example, greater hip extension (MB: 1.42 ± 0.29 vs. ML: 2.27 ± 0.45) and knee flexion (MB: −0.74 vs. ML: −1.17 nm/kg) moments were observed in the late swing phase. Additionally, the ML system’s estimations resulted in significantly smaller peak magnitudes for knee extension moment, along with the knee production power (p < 0.0001). Conclusions: These observations indicate that inconsistent estimates of joint center position and segment center of mass between the two systems may cause differences in the lower extremity joint moments and powers. However, with the progression of pose estimation in the markerless system, future applications can be promising.

Band structure engineering in Fe–Sb based lanthanide filled p-type skutterudites RFe4Sb12 (R = Nd, Sm) to enhance the Seebeck coefficient and thermoelectric figure of merit

Structural, thermodynamic, electronic, and thermoelectric properties of two pure ternary skutterudites, NdFe4Sb12 and SmFe4Sb12, and their doped counterparts, Sm-doped NdFe4Sb12 and Nd-doped SmFe4Sb12, have been investigated using full potential linearized augmented plane wave formalism under density functional theory. In doped systems, the central lanthanide atom was replaced by a different filler atom. Thermodynamic parameters indicate that all the materials are stable, sufficiently hard, and will have a high melting point. Band profiles reveal their semimetallic nature with a pseudo-bandgap above the Fermi level and crossing of the Fermi level of one or more bands. The facts that the trivalent fillers do not provide enough electrons required for charge compensation of Fe4Sb12 and the Fermi levels are well inside the valence band also predict their p-type nature. The splitting of DOS of the f-electrons of the filler atoms into both spin channels implies their ferromagnetic nature. The Sm-doped system exhibits the highest magnetic moment because of the much lower anti-ferromagnetic moment of Fe. Between the pure compounds, the lighter filler atom-based NdFe4Sb12 exhibits a higher ZT value because of the higher population density of states and higher concentration of degenerate flatbands. Contrary to recent predictions, both the doped systems show higher ZT than the pure ones. However, the presence of larger pseudo-bandgaps in both spin channels and two peaks just above the Fermi level in the majority spin channel in the lighter Nd-doped system results in the enhanced Seebeck coefficient, reduced thermal conductivity, and the maximum ZT value of 0.90 at 1000 K.

Differences in lower leg kinetics of soccer instep kicking between female and male players

ABSTRACT We aimed to clarify the difference in lower leg segment kinetics of soccer instep kicking between female and male players. Instep kicking motions of seven female and seven male university soccer players were captured at 500 Hz. Lower leg angular velocity, knee joint moment and the interaction moment acting on the lower leg were calculated. Discrete variables were compared using two sample-t-test, and statistical parametric mapping were used to compare the time-series changes between the two groups. Although female players maintained a comparable magnitude of lower leg angular velocity, they exhibited significantly lower knee extension moment in the latter part of kicking and significantly smaller forward angular impulse due to that moment. In contrast, female players were found to have a comparable magnitude of angular impulse due to forward component of interaction moment to that of male players. Eventually, female players come to have significantly larger ratio of angular impulses (forward interaction moment/knee extension moment) than male players. It can be considered that the forward component of interaction moment acting on the lower leg of female players may compensate their reduced exertion of knee extension moment, thereby achieving a comparable lower leg angular velocity to that of male players.

Contrasting seasons and land uses alter riverine dissolved organic matter composition

Different sources and fates control riverine dissolved organic matter (DOM) composition in catchments of contrasting land use and climate. However, assessing the changes in DOM composition together with nutrient forms along rivers exposed to these gradients remains rare. Here we quantified the spatial and temporal patterns in DOM components and nutrient forms along the mainstem of a 5th order river through sequential forested, urban, and agricultural reaches during low flow moments in summer and winter, and two contrasting springs, one with a historically rare flooding event. There were widespread abrupt shifts in the composition of DOM in low flow seasons that coincided with changes in land use whose sources could be inferred by endmember samples and nutrient changes. DOM pools considered bio- (microbial-like) and photo-labile (Peak C), along with reactive nutrient forms (ammonium, dissolved phosphorus) tended to accumulate during the winter compared to summer. This implied higher processing during summer as microbial-humic-like DOM and nitrate dominated. DOM composition remained relatively stable under typical spring high flow conditions with reduced retention time and processing, but major shifts were observed during an extreme flood year, pointing to unusual loadings of highly labile DOM. Overall, we found that despite relatively small changes in the quantity of DOM along the axis of flow in this north temperate river, there were major spatial and temporal shifts in its composition, associated with different nutrient forms. These changes inferred contrasting loading and processing potential depending on land use and seasonal patterns in temperature and hydrology.

The MOSDEF survey: a new view of a remarkable z = 1.89 merger

ABSTRACT We present a detailed study of a galaxy merger taking place at z = 1.89 in the GOODS-S field. Here, we analyse Keck/MOSFIRE spectroscopic observations from the MOSFIRE Deep Evolution Field (MOSDEF) survey along with multiwavelength photometry assembled by the 3D-HST survey. The combined data set is modelled to infer the past star formation histories (SFHs) of both merging galaxies. They are found to be massive, with log10(M*/M⊙) &amp;gt; 11, with a close mass ratio satisfying the typical major-merger definition. Additionally, in the context of delayed-τ models, GOODS-S 43114, and GOODS-S 43683 have similar SFHs and low star formation rates (log10(SFR(SED)/${\rm M}_{\odot }\,\rm {yr}^{-1}$) &amp;lt; 1.0) compared to their past averages. The best-fitting model SEDs show elevated H δA values for both galaxies, indicating that their stellar spectra are dominated by A-type stars, and that star formation peaked ∼0.5−1 Gyr ago and has recently declined. Additionally, based on SED fitting both merging galaxies turned on and shut off star formation within a few hundred Myr of each other, suggesting that their bursts of star formation may be linked. Combining the SFHs and H δA results with recent galaxy merger simulations, we infer that these galaxies have recently completed their first pericentric passage and are moving apart. Finally, the relatively low second velocity moment of GOODS-S 43114, given its stellar mass suggests a disc-like structure. However, including the geometry of the galaxy in the modelling does not completely resolve the discrepancy between the dynamical and stellar masses. Future work is needed to resolve this inconsistency in mass.

First Femoropopliteal Bypass for a Critical Limb Ischemia

First Femoropopliteal Bypass for a Critical Limb Ischemia

Immediate Effects of Manipulating Footwear or Cadence on the Lower Limb Biomechanics of Female Masters Runners.

The objective of this study was to compare the immediate effects of modifications to footwear or cadence on lower limb biomechanics of female Masters runners. After analyzing habitual treadmill running biomechanics in 20 female runners (52.4 [8.3]y), we assessed the effects of 5 conditions: (1)barefoot running, (2)Merrell Vapor Glove, (3)Merrell Bare Access, (4)Brooks Pure Flow, and (5)increasing cadence by 10%. In comparison with habitual biomechanics, greater vertical loading rates of the ground reaction force were observed during running barefoot or with a Merrell Vapor Glove or Bare Access. There was high variability among participants as to changes in foot kinematics during the conditions. Running barefoot (-26.0%) and with a Merrell Vapor Glove (-12.5%) reduced sagittal plane knee moments, but increased sagittal plane ankle moments (both 6.1%). Increasing cadence by 10% resulted in a more modest decrease in knee flexion moments (-7.7%) without increasing peak external ankle dorsiflexion moments. When asked if they would prefer minimalist shoes or increasing cadence, 11 participants (55%) chose cadence and 9 (45%) chose footwear. Minimalist footwear decreased sagittal knee moments, but increased vertical loading rate and sagittal ankle moments. Increasing cadence may be useful to lower sagittal knee moments without increasing ankle moments.

Far-from-equilibrium kinetic dynamics of λϕ4 theory in an expanding universe

We investigate the far-from-equilibrium behavior of the Boltzmann equation for a gas of massless scalar field particles with quartic (tree level) self-interactions ($\lambda \phi^4$) in Friedmann-Lemaitre-Robertson-Walker spacetime. Using a new covariant generating function for the moments of the Boltzmann distribution function, we analytically determine a subset of the spectrum and the corresponding eigenfunctions of the linearized Boltzmann collision operator. We show how the covariant generating function can be also used to find the exact equations for the moments in the full nonlinear regime. Different than the case of a ultrarelativistic gas of hard spheres (where the total cross section is constant), for $\lambda \phi^4$ the fact that the cross section decreases with energy implies that moments of arbitrarily high order directly couple to low order moments. Numerical solutions for the scalar field case are presented and compared to those found for a gas of hard spheres.

Charge Radii of ^{55,56}Ni Reveal a Surprisingly Similar Behavior at N=28 in Ca and Ni Isotopes.

Nuclear charge radii of ^{55,56}Ni were measured by collinear laser spectroscopy. The obtained information completes the behavior of the charge radii at the shell closure of the doubly magic nucleus ^{56}Ni. The trend of charge radii across the shell closures in calcium and nickel is surprisingly similar despite the fact that the ^{56}Ni core is supposed to be much softer than the ^{48}Ca core. The very low magnetic moment μ(^{55}Ni)=-1.108(20) μ_{N} indicates the impact of M1 excitations between spin-orbit partners across the N,Z=28 shell gaps. Our charge-radii results are compared to abinitio and nuclear density functional theory calculations, showing good agreement within theoretical uncertainties.

A first-principles study on the effect of Cr, Mn, and Co substitution on Fe-based normal- and inverse-Heusler compounds: Fe3−xYxZ (x=0, 1, 2, 3; Y= Cr, Mn, Co; Z=Al, Ga, Si)

First-principles calculation has become one of the most reliable approaches in predicting structural, electronic, and magnetic properties for material applications. Alloys in Heusler structures have also attracted much attention recently since they can be easily synthesized and provide interesting properties for future spintronic applications. In this work, we investigate a series of Fe-based Heusler compounds Fe3−xYxZ (x = 0, 1, 2, 3; Y= Cr, Mn, Co; Z= Al, Ga, Si) with L21- and XA-type structures using first-principles calculations based on density functional theory. According to formation energy calculations and mechanical property analysis, most of the studied Heusler compounds are thermodynamically stable and could be synthesized experimentally. The Co substitution leads Fe3−xCoxZ to a ferromagnetic ground state like Fe3Z with a strong magnetization ranging from 4 to 6 μB/f. u. While replacing Fe with Cr or Mn, the exchange coupling between Cr (Mn) and its neighboring atoms generally tend to be anti-parallel. Among the antiferromagnetic compounds, Mn3Al and Mn3Ga are antiferromagnetic half metal while Mn3Si is ferrimagnetic half metal. These rarely found type of half metals with low magnetic moment and high spin polarization at the Fermi level are important for low energy consumption spintronic applications. The estimated Curie temperatures for Mn3Al, and Mn3Si and Co2FeSi (XA) are in good agreement with previously theoretical values, while for Fe3Al and Fe3Si, they are in good agreement with previous experimental results. The good consistency in Curie temperature demonstrates high reliability of our predictions based on first-principles calculations. As for the topological property aspect, we predict Fe2CrAl and Fe2MnAl as the 3-dimensional Weyl semimetal. Furthermore, Fe2CrSi is predicted to be the magnetic nodal-line semimetal. Interestingly, our mechanical property analysis demonstrates that Co3Si and Fe2CoSi (L21) exhibit ultraelastic metal behavior, which is of high potential in advanced mechanical industry. This work suggests that Heusler compounds are excellent candidates for future spintronics as well as for high-performance ultraelastic metals.

A Deep Learning-Based Assisted Teaching System for Oral English

The progress of global economic integration has forced English learners to have an urgent need to improve their oral English. College students’ oral English ability is currently the worst of the four abilities of listening, speaking, reading, and writing. The main reasons are internal and external. The internal reason is that the pronunciation characteristics of Chinese students are different from those of English. The external cause is that the practice environment and tools of oral English are not ideal, which affects the improvement of learners’ oral English. This study proposes using a deep learning algorithm (DLA) English in the evaluation of oral English quality to improve learners’ oral English level. The quality of oral English can be comprehensively evaluated in terms of pitch, speed of sound, and rhythm. The standard of pronunciation is the foundation of oral English and is the most critical factor. In many DLAs, the input unit of DNN at a certain moment and its upper and lower moment input units have no relationship and are independent of each other, and the timing dependencies of adjacent units are not fully considered. The results are generally not very good on speech recognition tasks. This study proposes a time-delay neural network (TDNN) and a long short-term memory (LSTM) network to calculate the posterior probability of the model state to model context-dependent features in order to solve this problem. The fusion model TDNN-LSTM is applied in the English spoken pronunciation recognition task. To compare the accuracy of oral English pronunciation, several classic DLAs are introduced. The experimental results show that the method described in this study has a number of advantages. Although the performance improvement of this method in terms of recognition accuracy is not large, a certain degree of improvement is also very important for the oral English teaching assistant system.

Effect of the TrFE Content on the Crystallization and SSA Thermal Fractionation of P(VDF-co-TrFE) Copolymers.

In this contribution, we study the effect of trifluoro ethylene (TrFE) comonomer content (samples with 80/20, 75/25, and 70/30 VDF/TrFE molar ratios were used) on the crystallization in P(VDF-co-TrFE) in comparison with a PVDF (Poly(vinylidene fluoride)) homopolymer. Employing Polarized Light Optical Microscopy (PLOM), the growth rates of spherulites or axialites were determined. Differential Scanning Calorimetry (DSC) was used to determine overall crystallization rates, self-nucleation, and Successive Self-nucleation and Annealing (SSA) thermal fractionation. The ferroelectric character of the samples was explored by polarization measurements. The results indicate that TrFE inclusion can limit the overall crystallization of the copolymer samples, especially for the ones with 20 and 25% TrFE. Self-nucleation measurements in PVDF indicate that the homopolymer can be self-nucleated, exhibiting the classic three Domains. However, the increased nucleation capacity in the copolymers provokes the absence of the self-nucleation Domain II. The PVDF displays a monomodal distribution of thermal fractions after SSA, but the P(VDF-co-TrFE) copolymers do not experience thermal fractionation, apparently due to TrFE incorporation in the PVDF crystals. Finally, the maximum and remnant polarization increases with increasing TrFE content up to a maximum of 25% TrFE content, after which it starts to decrease due to the lower dipole moment of the TrFE defect inclusion within the PVDF crystals.