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Background: Foot and ankle injuries have been noted as the most common in dancers. However, the variability of injury epidemiology across different dance genres has not been clearly evaluated. Herein, this study aimed to evaluate the prevalence and incidence of foot and ankle problems in pre-professional ballet, contemporary, and Chinese dancers. Methods: Participants (N = 54) were recruited from a local dance institution that offered a formal undergraduate dance program. Demographic characteristics and specifics of foot and ankle pain during dancing were collected through an online self-reporting survey from September 2018 to June 2019. Descriptive statistical analyses, including injury incidence and risk rates, were conducted. Results: The overall response rate was 69.3%, with a total of 88 subjects eligible for analysis of which the results from 54 subjects were ultimately analyzed. The incidence of foot and ankle pain during the academic year of 2018 to 2019 was highest in contemporary dancers (0.38 per 1,000 dance hours) when compared to that of ballet (0.32 per 1,000 dance hours) and Chinese dancers (0.22 per 1,000 dance hours). Prevalence of foot and ankle pain within the same year was 84% in ballet dancers, 79% in Chinese dancers, and 70% in contemporary dancers. Ballet dancers were six times more likely to suffer from pain in the Achilles region than Chinese and contemporary dancers (p < 0.01). Chinese dancers were found to experience more forefoot and midfoot problems compared to ballet and contemporary dancers (p < 0.05). Conclusion: This study illustrated that foot and ankle pain is highly prevalent among pre-profes- sional dancers. Ballet was associated with the highest prevalence of foot-ankle pain while contemporary dance was associated with the highest incidence. There were significant differences of foot and ankle pain among dance genres and anatomical subregions, which suggests a need for targeted genre-specific injury prevention programs in hopes of preventing potentially career-ending injuries in dancers.

Purpose: The purpose of current study was to evaluate change in hours of Applied Behavior Analysis (ABA) therapy utilization for autistic children during the year prior to the COVID-19 pandemic, the first three months of the pandemic (crisis phase), and the following 9 months of the pandemic (mitigation phase). Additionally, this study aimed to evaluate if change in therapy utilization differed based on child race, ethnicity, and primary payer of services. Finally, we aimed to identify potential mechanisms of ABA therapy disruption by interpreting findings using an extended version of Donabedian’s structure-process-outcome model. Methods: Retrospective clinical data on client demographics and therapy utilization (n = 283) were collected from ABA clinics in California and analyzed with four piecewise growth multi-level models. Results: We found that therapy utilization dropped during the first three months of the pandemic (-10.65 h/month; p Conclusion: Findings suggest that utilization of ABA therapy was disrupted for a full year following the onset of the COVID-19 pandemic and that child race/ethnicity and primary payer influenced the degree to which autistic children were impacted by service disruption. These findings have implications for autistic children who lost therapy access during key developmental periods and for the ABA care delivery system.

Background: Noninvasive imaging of molecular alterations after intracerebral hemorrhage (ICH) could provide valuable information to guide and monitor treatments. Chemical exchange saturation transfer (CEST) magnetic resonance imaging has demonstrated promises in identifying proliferation, necrosis, and changes in cellularity in brain tumors. Here, we applied CEST magnetic resonance imaging to monitor molecular changes in hematoma without and with treatment noninvasively over 2 weeks at 3T using endogenous contrast. Methods: CEST contrast related to proteins at 3.5 ppm (amide proton transfer) and proteins/lipids at −3.5 ppm (relayed nuclear overhauser effect [rNOE]) were examined over 14 days in a collagenase-induced ICH mouse model. Imaging findings were validated with immunohistochemistry based on the ICH neuropathology. We also examined iron-containing phantoms that mimicked iron concentrations in hematoma to ensure the iron will not attenuate the CEST contrast during disease progression. Based on the validity of the CEST contrast of hematoma, we further examined related molecular alterations under iron-chelation treatment with deferoxamine. Results: We observed the temporal and spatial differences of CEST contrasts between rNOE at −3.5 ppm and amide proton transfer at 3.5 ppm, in which the core and perihematoma could be identified by rNOE on day 3 and day 14, and amide proton transfer on day 1, day 7, and day 14. Moreover, we observed a 25.7% significant reduction ( P Conclusions: Significant rNOE changes correlated well with histologic findings, especially myelin lipids, and regional characteristics in hematoma indicate the uniqueness of CEST magnetic resonance imaging in monitoring molecular changes during ICH and treatment.

Despite the growing recognition of a host genetic effect on shaping gut microbiota composition, the genetic determinants of oral microbiota remain largely unexplored, especially in the context of oral diseases. Here, we performed a microbiome genome-wide association study in 2 independent cohorts of patients with oral squamous cell carcinoma (OSCC, n = 144 and 67) and an additional group of noncancer individuals ( n = 104). Besides oral bacterial dysbiosis and signatures observed in OSCC, associations of 3 loci with the abundance of genus-level taxa and 4 loci with β diversity measures were detected ( q < 0.05) at the discovery stage. The most significant hit (rs10906082 with the genus Lachnoanaerobaculum, P = 3.55 × 10–9 at discovery stage) was replicated in a second OSCC cohort. Moreover, the other 2 taxonomical associations, rs10973953 with the genus Kingella ( P = 1.38 × 10–9) and rs4721629 with the genus Parvimonas ( P = 3.53 × 10–8), were suggestive in the meta-analysis combining 2 OSCC cohorts. Further pathway analysis revealed that these loci were enriched for genes in regulation of oncogenic and angiogenic responses, implicating a genetic anchor to the oral microbiome in estimation of casual relationships with OSCC. Our findings delineate the role of host genotypes in influencing the structure of oral microbial communities.

Background Cancer-related fatigue (CRF), cachexia, or poor performance status, which occurs among patients with advanced malignancy, has always frustrated clinicians and patients and been primarily managed via conservative treatments. The botanically derived drug extracted from Astragalus membranaceus(PG2) has been approved by Taiwan FDA as a standard of choice for CRF management. We show real-world practice about combination treatment of PG2, dose-modified chemotherapy, and anti-PD1 checkpoint inhibitor in patients with advanced malignancy with cachexia, fatigue, or poor performance status here. Methods We conducted a retrospective chart review of patients with advanced malignancy with CRF or cachexia who received a combination treatment mentioned above from Dec. 2016 to Dec. 2018. Results The medical charts of 23 patients with different malignancies who received PG2 during the systemic treatment, including chemotherapy and immunotherapy, were reviewed. The following types of cancers were detected among these patients: digestive system (n = 7), head and neck (n = 7), gynecological (n = 6), and others (n = 3). During recruitment, 22 patients had stage IV cancer. The initial ECOG performance status was 1 (n = 5), 2 (n = 11), > 2 (n = 7). The objective responses were 3 CR (13%), 13 PR (57%), 1 SD (4%), 5 PD (22%), and 1 death with treatment related tumor lysis syndrome of 6 days (4%). The median overall survival (OS) was 20.5 months (95% CI = 14.364, 26.636). The median progression-free survival (PFS) was 11.6 months (95% CI = 2.017, 21.249). Adverse events included anorexia (30%), neutropenia (26%), pneumonia (22%), nephrotoxicity (13%), and nausea and vomiting (13%). The adverse effect for grade 3/4/5 was rare. Conclusions This retrospective study provided real-world data for the management of initially presenting CRF, cachexia, or poor performance status with PG2 injection in 23 advanced cancer patients. The treatment was relatively fair tolerated with impressive results of OS and PFS. Further prospective study of combination therapies including immunotherapy and PG2 injection is warranted for more robust evidence. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

Background Propofol is an anesthetic with pluripotent cytoprotective properties against various extrinsic insults. This study was designed to examine whether this agent could also ameliorate the infamous toxicity of doxorubicin, a widely-used chemotherapeutic agent against a variety of cancer diseases, on myocardial cells. Methods Cultured neonatal rat cardiomyocytes were administrated with vehicle, doxorubicin (1 μM), propofol (1 μM), or propofol plus doxorubicin (given 1 h post propofol). After 24 h, cells were harvested and specific analyses regarding oxidative/nitrative stress and cellular apoptosis were conducted. Results Trypan blue exclusion and MTT assays disclosed that viability of cardiomyocytes was significantly reduced by doxorubicin. Contents of reactive oxygen and nitrogen species were increased and antioxidant enzymes SOD1, SOD2, and GPx were decreased in these doxorubicin-treated cells. Mitochondrial dehydrogenase activity and membrane potential were also depressed, along with activation of key effectors downstream of mitochondrion-dependent apoptotic signaling. Besides, abundance of p53 was elevated and cleavage of PKC-δ was induced in these myocardial cells. In contrast, all of the above oxidative, nitrative and pro-apoptotic events could be suppressed by propofol pretreatment. Conclusions Propofol could extensively counteract oxidative/nitrative and multiple apoptotic effects of doxorubicin in the heart; hence, this anesthetic may serve as an adjuvant agent to assuage the untoward cardiac effects of doxorubicin in clinical application.

Gold nanowires were prepared via seed-mediated growth process. Standard X-ray powder diffraction pattern of nanowires and foil are nearly identical. The intensities of the (2 2 0) and (1 1 1) diffraction peaks was higher than the conventional value, which implied that the nanowires were abundant in {1 1 0} facets. This is in accordance with electron diffraction analysis of mature nanowires, the wires grow along the [1 1 0] directions. X-ray absorption spectroscopy indicates that coordination number of gold nanowires was slightly smaller than that gold foil. Moreover, the Debye–Waller factor of the refinement result of gold nanowires implies that there were some structural defects.

This paper introduces the meshless local radial point interpolation method to model eddy-current problems for the first time. The formulation is described and results are compared with those from the ordinary finite-element simulation and the analytical solution

We propose a finite-element scheme which involves the use of the Lagrangian interface technique to model electromagnetic signal propagation in mixed regions of very low and high conductivity. The method has relevance to modeling underground communications in oil or gas wells. There will be a significant jump in electrical conductivity especially at the interface between the iron and the nonmetallic conductive regions

This paper describes a three-dimensional (3-D) overlapping finite-element scheme for modeling movement in electromagnetic devices, which results in a continuously changing air gap. The method uses separate finite-element meshes to model the individual parts of the device. These meshes are coupled together electromagnetically on an interface using the Lagrange sliding interface technique. Treatments of overlapping mesh volumes are also discussed. The method was used to model a jumping eddy-current disc experiment. The results of the simulations compared favorably with measurements.

Despite worldwide efforts and many recent advances, electrical machine modeling using finite elements can be computationally very expensive, especially if three-dimensional models are required. This contribution is concerned with speeding up the process. Some examples of line start permanent magnet machines and induction motors are provided.

The transient characteristics of an experimental test rig consisting of a fixed solid iron stator and moving rotor, when subjected to a step input voltage, are measured. A three-dimensional finite-element scheme that takes into account the nonlinear magnetic properties, eddy-current effects, and the dynamic motion of the rotor was used to simulate the response of the rig. The measurements were used as a benchmark against which the simulation results were compared.

Four finite-element formulations for modeling eddy current problems which involve a rotating conductor are examined and compared. The formulations are based on the A-/spl psi/ representation. The first formulation uses a single fixed mesh, nodal A elements and the Minkowski transformation. The other three schemes have two meshes coupled using a Lagrange interface and the mesh containing the conducting region rotates. Two of the schemes use a nodal A formulation and the third uses edge A elements. The main purpose of the paper is to point out some of the pitfalls which can occur when modeling rotating conductors. By way of example, the four formulations are applied to a spinning annulus test problem.

One major factor of red blood cell damage induced by artificial heart valves is the magnitude of turbulent shear stresses in the flow field. An often-cited threshold for hemolysis is 400 N/m(2) (Sallam and Hwang, Biorheology 21 (1984) 783). This value, however, was measured with a one-component laser Doppler anemometer and was not calculated from the major principal Reynolds shear stress, therefore underestimating the threshold. This study performed flow field measurements under similar conditions, using a two-component laser Doppler anemometer and determining major principal Reynolds shear stress, to reevaluate the hemolytic threshold as 800 N/m(2) with an exposure time of 1 ms. The Kolmogorov length scales, approximately 9 microm, are capable of inflicting direct damage to the red blood cells. These results will serve as a more accurate reference in future heart valve design and testing.

The electromagnetic launcher at speed is a challenging computational problem as fast time transient electromagnetic fields are involved and the velocity of the moving parts is designed to be very high. A large number of formulations are now available for modeling the electromagnetic behavior of moving conductor devices in 3D. These methods vary in computational expense and accuracy. In this paper, the authors describe and compare some of these methods, and show some examples.

A parameterization technique for use in optimizing electromagnetic devices is described. The method allows a rapid alteration of an initial template 2-D or 3-D finite element mesh of an electromagnetic device so that design studies or optimization be conveniently carried out. Two case studies are described. The examples consist of the voltage generated by a wound rotor generator and the performance of a Fluxset magnetic field measuring device.

A fast-converging solution method with strong coupling, which does not require the calculation of a global Jacobian, is discussed. The method is applied to an equilibrium-type coupled electromechanical system and also to the more general problem of the dynamic evolution of the system.

The authors describe the modeling of the transient dynamic behavior of a solenoidal core type electromagnetic actuator using an overlapping finite element (FE) scheme. The FE scheme allows two topologically unconnected 2D finite element meshes to slide over and overlap each other, whilst still coupled together electromagnetically in a consistent manner. The result is that the same set of FE meshes can be used to model directly a continuously shrinking or expanding air gap. This paper demonstrates, for the first time, that such a FE scheme can be used to model accurately the dynamic closing of the air gap of a linear actuator. The results of the simulation were compared with experimental measurements. It is shown that good agreement between simulated and measured results is obtained.

Some techniques for modeling thin skin depth eddy currents induced by the movement of a conductor through a magnetic field are described. The nonconducting regions are modeled using conventional volume finite elements in terms of the magnetic scalar potential /spl psi/. The magnetic fields in the thin skin are determined approximately using either analytic or numerical solutions to 1D equations for fields in the moving skin.

The treatment of 3D machine problems using the finite element method to model the field is examined. Methods for coupling to external circuits are reviewed and it is shown that symmetry can be taken care of by the suitable scaling of partitions of the system matrix. 3D filament wound coils and massive conductor circuits are discussed.

Two finite element implementations for modelling eddy current problems with velocity are examined here. The formulations are based on the A-/spl psi/ representation. In one finite element implementation, the moving current density is represented as a volume integral term. In the other, volume and surface integral terms represent the moving current density. These formulations are applied to a series of rotational velocity test models differing in conductor topology and the results are compared.

This paper describes a 3D finite element scheme for use in dynamic simulations of electromagnetic devices with moving parts connected to an external circuit. The scheme handles source coils through a special coil region based on the magnetic scalar representation with an additional basis for each coil. The finite element model can be directly coupled to external circuits and motion of moving parts within the model is handled by using a Lagrange sliding interface technique.

This paper describes an efficient scheme for incorporating multiple wire wound coils into 3D finite element electric machine models. The scheme is based on the magnetic scaler representation with an additional basis for each coil. There are no restrictions on the topology of coils with respect to ferromagnetic and conductor regions. Reduced scaler regions and cuts are automatically generated.

The occurrence of tributyltin (TBT) is reported in the coastal waters of a few selected sites in Peninsular Malaysia. Water, bivalves and sediment samples collected were analysed specifically for TBT using sensitive analytical methods which involved a solvent extraction procedure with appropriate clean-up followed by graphite furnace atomic absorption spectrometric measurements. The levels of TBT in the seawater in unexposed areas were found in the range from3.4 to 20 ng litre(-1) as compared to coastal areas with high boat and ship activities where TBT levels in seawater were generally above 30 ng litre(-1), with the highest level found at 281.8 ng litre(-1). TBT levels in the tissues of random cockle and soft-shell clam samples from local markets were found in the range from0.5 to 3.7 ng g(-1) wet weight. The levels of TBT found in green mussel samples both from the market (23.5 ng g(-1) wet weight) and those from a mussel farm (14.2 ng g(-1) wet weight) indicate slight accumulation of TBT. In sediments, TBT levels were found ranging from0.7 ng g(-1) dry weight in unexposed coastal sites to as high as 216.5 ng g(-1) dry weight for a site within a port area.

In-situ growth of 2-in. diameter superconducting YBa 2 Cu 3 O 7− x (YBCO) thin films using an excimer KrF pulsed laser has been studied. Films with critical transition temperature ( T c,0 ) of 89 ± 1 K and critical current density ( J c,77K ) in excess of 1 × 10 6 A cm −1 have been prepared routinely. Uniformity in film thickness of below ±15% and film composition of ±5% have been measured. The effects of gas nozzle geometry and target evolution during ablation on the superconducting properties and surface morphology of YBCO thin films have also been investigated.

Meshless methods are a new class of numerical techniques for solving partial differential equations and have attracted considerable attention in computational mechanics in recent years. Owing to the ‘mesh-free’ characteristic, these methods offer some advantages over the conventional mesh-based finite-element techniques. A formulation for the meshless local Petrov–Galerkin method is described and its application to electromagnetic modelling investigated.

Measurements of the performance of a 5-kVA induction machine are compared with predictions carried out using finite elements and semianalytic techniques. Both transient and steady-state performance results are compared and sufficient dimensions are provided that others may use the experimental results as a benchmark.

A method for finite element modelling of transient 3D eddy currents in magnetically nonlinear media is described. The magnetic vector potential A, with or without the electric scalar potential V, is used inside eddy current regions, coupled to magnetic scalar potentials elsewhere. Time transient torque, current and flux values are compared to measurements taken from a rotational test rig. >

Laminar mixed convection heat transfer in a horizontal isothermal cooled tube for high Rayleigh numbers and Prandtl numbers is investigated numerically in the present study. The inlet fluid with a fully developed inlet velocity and a constant inlet temperature T 0 is cooled in the tube with a constant wall temperature T w . Variation of the fluid and wall temperature difference and the heat transfer are governed by the Rayleigh number and the Graetz number. To achieve the high Rayleigh number solution in a sufficiently long range of z , a robust scheme of weighting function for solving the energy equation and a control volume method for evaluating the wall temperature gradient are employed. The varying Nu with Ra = 0 ~ 5 × 10 8 in the range of z = 0−0.8 is obtained. This extends the solution to three orders higher in Ra and one order longer in z than those in the literature. Several axial positions characterizing the Nusselt number curve for each Ra are identified and correlated. Comparisons of Nu with the existing experimental data for Ra in the orders of 10 3 –10 8 are made.

In this letter, we demonstrate an experimental study of using a large area oxide-confined vertical-cavity surface-emitting laser (VCSEL) to pump a Nd:YVO/sub 4/ microchip laser. The maximum output power of 1.2 mW in TEM/sub 00/ mode is obtained with a pump power of 8.2 mW. Experimental results show that the complex transverse modal behavior of VCSELs in the higher injection current may cause an impediment of power scaling.

A novel scheme for automatically generating cuts in the magnetic scalar region of a finite element mesh is presented. Cuts are generated allowing multiply connected eddy current problems to be solved. The scheme has no topological limitations; it has been tested for knotted conductors, interlinked conductors, and hollow conductors. The scheme is fully automatic, requiring just a standard well-formed finite element mesh and appropriate boundary conditions. It has been implemented and tested in the finite element package MEGA for the A psi formulation. >

The use of surface impedance elements and the use of volume elements when modeling at test rig using the MEGA package are compared. The test rig is representative of a turbine generator. The work is supported by practical measurements. Experimental results indicate that it is possible to model 3-D fields in large-scale objects containing nonlinear conducting iron using finite elements. Two methods for modeling the iron are compared: conventional volume elements and surface impedance elements. Both methods give similar results, but the latter method is much more economical. Some complex devices are impractical to model on inexpensive workstations without using surface impedance elements. >

The authors present a scheme for modeling coil guns using finite elements. The relative motion between the coils and the projectile is modeled by using two distinct meshes which are coupled using Lagrange multipliers which depend on the relative position of the two meshes. This scheme allows the inner mesh to slide during the transient simulation without the need to remesh the problem. Results are presented for a simple experiment involving a single coil and aluminum projectile. >

This paper describes a scheme which allows two separate finite element meshes to slide into and thus overlap each other. The Lagrange multipliers method is used to couple the two meshes together at their boundary. Overlapping elements are dealt with by adjusting the contributions of the elements of one of the two meshes to the system matrix according to the extent of overlap in such a way that at total overlap, those elements are effectively decoupled from the model. Applications include the modelling of electromagnetic plunger type devices.

A new technique for modelling time transient thin skin depth eddy currents is presented. The nonconducting regions are modelled using conventional volume finite elements in terms of the magnetic scalar potential /spl psi/. The magnetic fields in the thin skin are determined approximately using 1D finite elements in terms of magnetic vector potentials, Most problems would result in one large volume matrix and many small 1D matrices. A staggered time transient solution to the two sets of equations in /spl psi/ and A is then carried out. A finite element implementation and some test examples are described.

In this paper, a high-speed full swing CMOS driver for TFT-LCD scan-line circuit is presented. High driving capability is achieved by a proposed complementary dual-bootstrap (CDUB) technique. The scan-line CDUB driver was fabricated in a 0.35 mum CMOS technology. The measured results, under the TFT-LCD scan-line load model, indicate that the delay time is within 2.8 mus and the average power is 0.74 mW for a 5 V supply voltage.

A high-performance gate driver for active matrix TFT-LCD application is presented. High driving capability and low power characteristic are achieved by the proposed single capacitor bootstrap (SCB) technique. Simulation results indicate that the average power is 1.5 mW with 5 V supply voltage when simulated in a 0.35-mum CMOS technique. It is effective for high resolution and low power LCD drivers.

A CMOS voltage reference, which is based on the same magnitude of gate-source voltage of an NMOS and a PMOS operating in saturation region, is presented. The voltage reference is designed for CMOS low-dropout linear regulators and has been implemented in TSMC 0.18 mum CMOS process. The effect area is only 18 mu m times 25 mu m. It gives a temperature coefficient of not greater than 0.68 ppm/degC from -70degC to 150degC without trimming, while consuming a maximum of 1 mu A with a supply voltage of 0.9 V.

In the paper we present a 5.7 GHz gain-variable LNA. This LNA is designed in TSMC CMOS 0.18-mum technology based on an improved current-reused cascade common source topology. High gain and low power is achieved. The variable gain range is from 20.73 to 14.6 dB. The LNA achieves 20.73 dB gain, 3.08 dB noise figure, 3 dBm IIP3, and -36.32 dB input return loss at lower gain.

This paper demonstrates the design of a 3.1 GHz to 10.6 GHz low noise amplifier for UWB applications. It adopts a current-reused technique and a high-pass input matching network for high gain and low noise design. The designed LNA shows a 15.1 to 16.1 dB power gain and a good input matching of 50 Omega in the desired bands. The maximum variation of gain is less than 1 dB. The simulated noise figure is between 2.3 dB to 3.2 dB and the input return loss is below -10 dB, under 1.8V supply voltage in TSMC CMOS 0.18 mum technology.

Radial basis functions are a powerful interpolation technique that has become increasingly popular as a mesh free tool to solve partial differential equations. In this paper, the meshless multiquadric RBF is used and some of the issues related to its accuracy are investigated

The action of many electrical machines is based on magnetic forces in salient structures. Examples are switched reluctance machines, magnetic bearings etc. The force production behaviour of many of these machines can be approximately described using analytic methods, based for example on simple magnetic circuits and the principal of virtual work. These methods are well known to be very poor where non linearities are involved. Here, we present simple models which can be used in the initial part of a design of many such machines. These models are non linear and are based on parameterized finite element models

A new electrical machine which starts directly on line and does not require power electronics has been developed. Compared with the standard line start induction motor it has about 30% less losses and a similar starting performance. The new machine has a conventional stator and a two part rotor.