bluuebunny/crossref_metadata_2025_split huggingface dataset:
Are Medial and Lateral Tibiofemoral Compressive Forces Different in Uphill Compared to Level Walking for Patients Following Total Knee Arthroplasty?
Authors: Thorsen Tanner , Wen Chen , Zhang Songning 
Published: May 2021

Abstract
The purpose of this study was to determine how tibiofemoral joint compressive forces and knee joint-spanning muscle forces during uphill walking change compared to level walking in patients with total knee arthroplasty (TKA). A musculoskeletal model capable of resolving total (TCF), medial (MCF), and lateral (LCF) tibiofemoral compressive forces was used to determine compressive forces and muscle forces during level and uphill walking on a 10 deg incline for twenty-five post-TKA patients. A 2 × 2 (slope: level and 10 deg × limb: replaced and nonreplaced) repeated measures analysis of variance was used to detect differences in knee contact forces between slope and limb conditions and their interaction. Peak loading-response TCF, MCF, and LCF were greater during uphill walking than level walking for nonreplaced limbs. During uphill walking, peak loading-response TCF was smaller in replaced limbs compared to nonreplaced limbs with no change in MCF or LCF. Peak knee extension moment and knee extensor muscle force were smaller in replaced limbs compared to nonreplaced limbs during uphill walking. During level walking, replaced and nonreplaced limbs experienced rather equal joint loading; however, replaced limb experienced reduced joint loading during uphill walking. Differences in joint loading between replaced and nonreplaced limbs were not present during level walking, suggesting compensation from the replaced limb during the more difficult task. Uphill walking following TKA promotes more balanced loading of replaced limbs during stance; however, these benefits may come at the expense of increased loading on nonreplaced limbs.
Vibratory Conveying by Harmonic Longitudinal and Polyharmonic Normal Vibrations of Inclined Conveying Track
Authors: Ihor Vrublevskyi 
Published: May 2021

Abstract
Vibratory conveying of a material point by harmonic longitudinal and polyharmonic normal vibrations of an inclined conveying surface is considered. The dependence of dimensionless conveying velocity—a ratio of velocity to the product of frequency and amplitude of longitudinal vibration—on several dimensionless parameters is investigated in the moving modes without hopping. Maximal conveying velocity is achieved at the certain values of normal vibration amplitudes and phase difference angle between the longitudinal and normal vibrations, which are called optimal. Their values are dependent on two dimensionless parameters: the inclination angle parameter—a ratio of an inclination angle tangent to a frictional coefficient, the intensive vibration coefficient—a ratio of the longitudinal amplitude of vibration to the amplitude of the first harmonic of normal vibration and frictional coefficient. In a condition of the intensive longitudinal vibration, when its amplitude significantly greater than amplitudes of normal vibration, dimensionless velocity is almost independent of the intensive vibration parameter and it depends only on inclination angle parameter, i.e., on inclination angle and frictional coefficient. The optimal values of harmonics’ amplitudes of polyharmonic normal vibration are determined in dependence of inclination angle parameter with the number of harmonics from 2 to 7. The graphs of considered dependencies are presented and the most important values of parameters are presented in the table. Conclusions are made to determine the optimal vibration parameters and the problems of further research are indicated. The considered vibrations can be used in different vibratory conveying devices with electromagnetic drives.
Active Vibration Control of a Multi-Degree-of-Freedom System via Twin Rotor Damper
Authors: Terrill Richard , Starossek Uwe 
Published: May 2021

Abstract
The twin rotor damper (TRD), an active mass damping device, is used for the vibration control of a multi-degree-of-freedom (MDOF) system of oscillators. A single TRD unit consists of two eccentric control masses rotating about two parallel axes. In its principle mode of operation, the continuous rotation mode (CRM), the control masses rotate with a constant angular velocity in opposite directions; producing a monofrequent harmonic control force in an energy and power efficient manner. Extensive research has shown the effectiveness of the TRD in the CRM for systems with a single dominate mode of vibration. In this paper, the application of a single and multiple TRD units operating in the CRM is investigated for the control of a MDOF system of oscillators. The influence of the monofrequent control force produced by the TRD on the MDOF system of oscillators is investigated analytically. Subsequently, the analysis is inverted and the influence of the MDOF system of oscillators on the TRD is studied, in particular its power efficiency and damping performance. Finally, the power efficiency and damping performance of the TRD for the control of a system with two modes of vibration is analytically compared with that of a conventional active mass damping (CAMD) device. It is shown that in most cases, the TRD achieves greater damping performance in a more power efficient manner than a conventional active mass damper of similar size and mass.
Effect of Ultralow Concentrated Reduced Graphene Oxide Nanofluid on Radiator Performance
Authors: Ponangi Babu Rao , Krishna V. , Seetharamu K. N. 
Published: May 2021

Abstract
Nanocoolants are engineered colloidal suspensions of nanoparticles in a conventional coolant (water–ethylene glycol). Use of metals and metallic oxide nanofluids at concentrations greater than 0.01 vol % has been studied in greater detail compared to functionalized graphene nanofluids. In the present work, an experimental investigation is carried out on an automobile radiator by changing the conventional coolant to reduced graphene oxide (RGO) nanocoolant. The present study focuses on the effect of ultralow nanoparticle concentration (0.002–0.006 vol %), Reynolds number of hot coolant (80–170), Reynolds number of air (210–270), and inlet temperature of hot coolant (40 °C and 60 °C). The effect of these parameters on the performance of the radiator is measured in terms of convective heat transfer coefficient (CHTC), Nusselt number, friction factor, and effectiveness. Results indicate that at 0.006 vol % concentration, there is a maximum increase of 100.5% and 111%, respectively, in CHTC and effectiveness, besides a reduction in friction factor. RGO nanocoolant offers great scope for reducing the radiator size and increasing its performance.
The Role of Secondary Flows and Separation in Convective Heat Transfer in a Rotating Radial Vane Brake Disk
Authors: Atkins Michael D. , Kienhöfer Frank W. , Lu Tian Jian , Chang Se-Myong , Kim Tongbeum 
Published: May 2021

Abstract
This study presents, for the first time, distributions of local internal temperature and convective heat transfer in a rotating radial vane brake disk and explains mechanisms in conjunction with secondary flows and flow separation within its ventilated coolant passages. In particular, variations of radial, circumferential (vane-to-vane), and axial (inboard-to-outboard) heat transfer on internal end-wall surfaces, and their alteration due to varying number of radial vanes and rotating speed are experimentally detailed. It has been demonstrated that conventional ventilated radial brake disks where the air inflow is drawn from the inboard face are likely to suffer substantial axial variations of temperature and heat transfer between the inboard and outboard disks, which possibly exacerbates thermal distortion (i.e., coning). Further, for a typical number of vanes (i.e., 36 vanes) used on automobiles, internal thermal distributions are highly nonuniform. However, the thermal end-wall uniformity improves considerably as the number of vanes is increased to say 72 vanes. Specifically, as the number of vanes is increased, secondary flow mixing enhances overall convective heat transfer and improves thermal uniformity. In contrast, separation causes large end-wall thermal nonuniformities in radial and circumferential distributions between the pressure side and the suction side of radial vanes. This effect nonetheless also decreases as the number of vanes is increased.
Cardiovascular Effects of Aerobic Exercise With Self-Selected or Predetermined Intensity in Adolescents With Obesity
Authors: Barros Tércio A.R. , do Prado Wagner L. , Tenório Thiago R.S. , Ritti-Dias Raphael M. , Germano-Soares Antônio H. , Balagopal Babu P. , Hill James O. , Freitas-Dias Ricardo 
Published: May 2021

This study compared the effects of self-selected exercise intensity (SEI) versus predetermined exercise intensity (PEI) on blood pressure (BP) and arterial stiffness in adolescents with obesity. A total of 37 adolescents, 14.7 (1.6) years old, body mass index ≥95th percentile were randomly allocated into SEI (n = 18; 12 boys) or PEI (n = 19; 13 boys). Both groups exercised for 35 minutes on a treadmill, 3 times per week, for 12 weeks. The SEI could set the speed at the beginning of the sessions and make changes every 5 minutes. The PEI adolescents were trained at an intensity set at 60% to 70% of heart rate reserve. Brachial and central BP, pulse pressure, augmentation index, and carotid–femoral pulse wave were determined at baseline and after 12 weeks. Both groups reduced brachial systolic BP (SEI, Δ = −9 mm Hg; PEI, Δ = −4 mm Hg; P < .01), central systolic BP (SEI, Δ = −4 mm Hg; PEI, Δ = −4 mm Hg; P = .01), and central pulse pressure (SEI, Δ = −4 mm Hg; PEI, Δ = −3 mm Hg; P = .02) without differences between groups. No changes in the augmentation index and carotid–femoral pulse wave were observed in either group. The SEI induced similar changes in various cardiovascular outcomes compared with PEI in adolescents with obesity.
Tectonic evolution of the central California margin as reflected by detrital zircon composition in the Mount Diablo region
Authors: Gooley* Jared T. , Grove Marty , Graham Stephan A. 
Published: May 2021

ABSTRACT
The Mount Diablo region has been located within a hypothesized persistent corridor for clastic sediment delivery to the central California continental margin over the past ~100 m.y. In this paper, we present new detrital zircon U-Pb geochronology and integrate it with previously established geologic and sedimentologic relationships to document how Late Cretaceous through Cenozoic trends in sandstone composition varied through time in response to changing tectonic environments and paleogeography. Petrographic composition and detrital zircon age distributions of Great Valley forearc stratigraphy demonstrate a transition from axial drainage of the Klamath Mountains to a dominantly transverse Sierra Nevada plutonic source throughout Late Cretaceous–early Paleogene time. The abrupt presence of significant pre-Permian and Late Cretaceous–early Paleogene zircon age components suggests an addition of extraregional sediment derived from the Idaho batholith region and Challis volcanic field into the northern forearc basin by early–middle Eocene time as a result of continental extension and unroofing. New data from the Upper Cenozoic strata in the East Bay region show a punctuated voluminous influx (&gt;30%) of middle Eocene–Miocene detrital zircon age populations that corresponds with westward migration and cessation of silicic ignimbrite eruptions in the Nevada caldera belt (ca. 43–40, 26–23 Ma). Delivery of extraregional sediment to central California diminished by early Miocene time as renewed erosion of the Sierra Nevada batholith and recycling of forearc strata were increasingly replaced by middle–late Miocene andesitic arc–derived sediment that was sourced from Ancestral Cascade volcanism (ca. 15–10 Ma) in the northern Sierra Nevada. Conversely, Cenozoic detrital zircon age distributions representative of the Mesozoic Sierra Nevada batholith and radiolarian chert and blueschist-facies lithics reflect sediment eroded from locally exhumed Mesozoic subduction complex and forearc basin strata. Intermingling of eastern- and western-derived provenance sources is consistent with uplift of the Coast Ranges and reversal of sediment transport associated with the late Miocene transpressive deformation along the Hayward and Calaveras faults. These provenance trends demonstrate a reorganization and expansion of the western continental drainage catchment in the California forearc during the late transition to flat-slab subduction of the Farallon plate, subsequent volcanism, and southwestward migration of the paleodrainage divide during slab roll-back, and ultimately the cessation of convergent margin tectonics and initiation of the continental transform margin in north-central California.
Quantifying bankfull flow width using preserved bar clinoforms from fluvial strata
Authors: Greenberg Evan , Ganti Vamsi , Hajek Elizabeth 
Published: May 2021

AbstractReconstruction of active channel geometry from fluvial strata is critical to constrain the water and sediment fluxes in ancient terrestrial landscapes. Robust methods—grounded in extensive field observations, numerical simulations, and physical experiments—exist for estimating the bankfull flow depth and channel-bed slope from preserved deposits; however, we lack similar tools to quantify bankfull channel widths. We combined high-resolution lidar data from 134 meander bends across 11 rivers that span over two orders of magnitude in size to develop a robust, empirical relation between the bankfull channel width and channel-bar clinoform width (relict stratigraphic surfaces of bank-attached channel bars). We parameterized the bar cross-sectional shape using a two-parameter sigmoid, defining bar width as the cross-stream distance between 95% of the asymptotes of the fit sigmoid. We combined this objective definition of the bar width with Bayesian linear regression analysis to show that the measured bankfull flow width is 2.34 ± 0.13 times the channel-bar width. We validated our model using field measurements of channel-bar and bankfull flow widths of meandering rivers that span all climate zones (R2 = 0.79) and concurrent measurements of channel-bar clinoform width and mud-plug width in fluvial strata (R2 = 0.80). We also show that the transverse bed slopes of bars are inversely correlated with bend curvature, consistent with theory. Results provide a simple, usable metric to derive paleochannel width from preserved bar clinoforms.
Pace, magnitude, and nature of terrestrial climate change through the end-Permian extinction in southeastern Gondwana
Authors: Frank T.D. , Fielding C.R. , Winguth A.M.E. , Savatic K. , Tevyaw A. , Winguth C. , McLoughlin S. , Vajda V. , Mays C. , Nicoll R. , Bocking M. , Crowley J.L. 
Published: May 2021

Abstract
Rapid climate change was a major contributor to the end-Permian extinction (EPE). Although well constrained for the marine realm, relatively few records document the pace, nature, and magnitude of climate change across the EPE in terrestrial environments. We generated proxy records for chemical weathering and land surface temperature from continental margin deposits of the high-latitude southeastern margin of Gondwana. Regional climate simulations provide additional context. Results show that Glossopteris forest-mire ecosystems collapsed during a pulse of intense chemical weathering and peak warmth, which capped ∼1 m.y. of gradual warming and intensification of seasonality. Erosion resulting from loss of vegetation was short lived in the low-relief landscape. Earliest Triassic climate was ∼10–14 °C warmer than the late Lopingian and landscapes were no longer persistently wet. Aridification, commonly linked to the EPE, developed gradually, facilitating the persistence of refugia for moisture-loving terrestrial groups.
Revisiting stepwise ocean oxygenation with authigenic barium enrichments in marine mudrocks
Authors: Wei Guang-Yi , Ling Hong-Fei , Shields Graham A. , Hohl Simon V. , Yang Tao , Lin Yi-Bo , Zhang Feifei 
Published: May 2021

AbstractThere are current debates around the extent of global ocean oxygenation, particularly from the late Neoproterozoic to the early Paleozoic, based on analyses of various geochemical indices. We present a temporal trend in excess barium (Baexcess) contents in marine organic-rich mudrocks (ORMs) to provide an independent constraint on global ocean redox evolution. The absence of remarkable Baexcess enrichments in Precambrian (&gt;ca. 541 Ma) ORMs suggests limited authigenic Ba formation in oxygen- and sulfate-deficient oceans. By contrast, in the Paleozoic, particularly the early Cambrian, ORMs are marked by significant Baexcess enrichments, corresponding to substantial increases in the marine sulfate reservoir and oxygenation level. Analogous to modern sediments, the Mesozoic and Cenozoic ORMs exhibit no prominent Baexcess enrichments. We suggest that variations in Baexcess concentrations of ORMs through time are linked to secular changes in the marine dissolved Ba reservoir associated with elevated marine sulfate levels and global ocean oxygenation. Further, unlike Mo, U, and Re abundances, significant Baexcess enrichments in ORMs indicate that the overall ocean oxygenation level in the early Paleozoic was substantially lower than at present.
Detrital chromites reveal Slave craton's missing komatiite
Authors: Haugaard Rasmus , Waterton Pedro , Ootes Luke , Pearson D. Graham , Luo Yan , Konhauser Kurt 
Published: May 2021

Abstract
Komatiitic magmatism is a characteristic feature of Archean cratons, diagnostic of the addition of juvenile crust, and a clue to the thermal evolution of early Earth lithosphere. The Slave craton in northwest Canada contains &gt;20 greenstone belts but no identified komatiite. The reason for this dearth of komatiite, when compared to other Archean cratons, remains enigmatic. The Central Slave Cover Group (ca. 2.85 Ga) includes fuchsitic quartzite with relict detrital chromite grains in heavy-mineral laminations. Major and platinum group element systematics indicate that the chromites were derived from Al-undepleted komatiitic dunites. The chromites have low 187Os/188Os ratios relative to chondrite with a narrow range of rhenium depletion ages at 3.19 ± 0.12 Ga. While these ages overlap a documented crust formation event, they identify an unrecognized addition of juvenile crust that is not preserved in the bedrock exposures or the zircon isotopic data. The documentation of komatiitic magmatism via detrital chromites indicates a region of thin lithospheric mantle at ca. 3.2 Ga, either within or at the edge of the protocratonic nucleus. This study demonstrates the applicability of detrital chromites in provenance studies, augmenting the record supplied by detrital zircons.
Evidence for iron-rich sulfate melt during magnetite(-apatite) mineralization at El Laco, Chile
Authors: Bain Wyatt M. , Steele-MacInnis Matthew , Tornos Fernando , Hanchar John M. , Creaser Emily C. , Pietruszka Dorota K. 
Published: May 2021

Abstract
The origins of Kiruna-type magnetite(-apatite) [Mt(-Ap)] deposits are contentious, with existing models ranging from purely hydrothermal to orthomagmatic end members. Here, we evaluate the compositions of fluids that formed the classic yet enigmatic Mt(-Ap) deposit at El Laco, northern Chile. We report evidence that ore-stage minerals crystallized from an Fe-rich (6–17 wt% Fe) sulfate melt. We suggest that a major component of the liquid was derived from assimilation of evaporite-bearing sedimentary rocks during emplacement of andesitic magma at depth. Hence, we argue that assimilation of evaporite-bearing sedimentary strata played a key role in the formation of El Laco and likely Mt(-Ap) deposits elsewhere.
Assessing the effectiveness of workplace accommodations in facilitating return to work after traumatic brain injury: a systematic review protocol
Authors: Shafi Reema , Colantonio Angela 
Published: May 2021

IntroductionReturning to work and sustaining employment can be a significant challenge for traumatic brain injury (TBI) survivors. Within the literature, there is recurring support for the role of workplace accommodations in effective and early return-to-work (RTW). To date, however, there has been a lack of systematic reviews exploring the specific role of workplace accommodations within the context of RTW after TBI. The primary objective of this protocol is to outline the methodological approach that will be undertaken to systematically review the literature and to assess the effectiveness of workplace accommodations in facilitating RTW.Methods and analysisA total of nine databases will be searched systematically using the concepts ‘Brain injury,’ ‘RTW’ and ‘Job Accommodations.’ Study selection will be performed independently by three reviewers, based on predetermined eligibility criteria through two rounds of screening using, first, the title and abstract, followed by a full-text search. Extracted information will include the study’s purpose, design, and setting; the data source and type; the severity of TBI and the diagnostic criterion used; a comprehensive description of the intervention provided; the RTW outcome variables and the statistical methods used, etc. The data will be tabulated and narratively synthesised. Systematic review registration: This protocol has been registered with International Prospective Register of Systematic Reviews.Ethics and disseminationAs this review intends to use pre-existing published studies hence research ethics board approvals will not be required. Nevertheless, this review will follow the ethical and governance standards in the data management and presentation of results. The findings from this review will potentially be published in a peer-reviewed scientific journal (electronically and in print). The results of this review will be presented at both national/international conferences and shared with stakeholders influencing RTW practices.PROSPERO registration numberCRD42016043517.