Longitudinal Rotation Research Articles

Framework for lumen-based nonrigid tomographic coregistration of intravascular images.

Purpose: Modern medical imaging enables clinicians to effectively diagnose, monitor, and treat diseases. However, clinical decision-making often relies on combined evaluation of either longitudinal or disparate image sets, necessitating coregistration of multiple acquisitions. Promising coregistration techniques have been proposed; however, available methods predominantly rely on time-consuming manual alignments or nontrivial feature extraction with limited clinical applicability. Addressing these issues, we present a fully automated, robust, nonrigid registration method, allowing for coregistering of multimodal tomographic vascular image datasets using luminal annotation as the sole alignment feature. Approach: Registration is carried out by the use of the registration metrics defined exclusively for lumens shapes. The framework is primarily broken down into two sequential parts: longitudinal and rotational registration. Both techniques are inherently nonrigid in nature to compensate for motion and acquisition artifacts in tomographic images. Results: Performance was evaluated across multimodal intravascular datasets, as well as in longitudinal cases assessing pre-/postinterventional coronary images. Low registration error in both datasets highlights method utility, with longitudinal registration errors-evaluated throughout the paired tomographic sequences-of ( longitudinal image frames) and ( frame) for multimodal and interventional datasets, respectively. Angular registration for the interventional dataset rendered errors of , and for the multimodal set. Conclusions: Satisfactory results across datasets, along with additional attributes such as the ability to avoid longitudinal over-fitting and correct nonlinear catheter rotation during nonrigid rotational registration, highlight the potential wide-ranging applicability of our presented coregistration method.

Numerical verification for concrete beams reinforced with CFRP subjected to pure torsion

Torsional behavior of concrete beams reinforced with longitudinal Fiber reinforced polymers (FRP) bars and FRP transverse stirrups has not been well-defined in various international codes and design guidelines as evidenced from the discrepancies in design equations. Such discrepancies are due to the complex behavior of beams subjected to torsional stresses and the limited research available in the literature; especially for FRP reinforced beams. A non-linear finite element (FE) analysis is conducted using ATENA software to generate a numerical model to predict and verify the failure loads and strains of beams of a compiled database from literature. This paper presents a comparison between the results of the experimental data and analytical models in order to verify the efficiency of the proposed numerical model for predicting failure load/strains in longitudinal FRP bars, FRP stirrups, and rotation angle of the tested beams. The comparison showed good agreement between experimental and analytical models in ultimate torque with difference of 6.5 % and the model is used in a parametric study to investigate the effect of concrete compressive strength, longitudinal reinforcement ratio, and beam depth under pure torsion in addition to the effect of concrete contribution to the torsional resistance. The numerically computed cracking and ultimate torques are compared with results from theory of elasticity, skew-bending theory and code equations such as: ACI-318 and CSA-S806-12. Based on this study, CSA-S806 gives acceptable prediction of ultimate torque, while ACI code is found to be more conservative. The increase of concrete compressive strength can enhance the cracking and ultimate torque. The increase of longitudinal reinforcement ratio has an insignificant effect on ultimate torque but increases the twist capacity of Reinforced concrete (RC) beams. The increase of longitudinal reinforcement can improve also the twist ductility.

Theoretical and experimental analyses of high-speed seed filling in limited gear-shaped side space of cotton precision dibbler

A novel state-of-motion adjustment method of seeds for high-speed seed filling in a cotton precision dibbler is proposed to solve the problems of arch lifting (multiple particles squeezing each other and causing congestion) and leakage (caused by exceedingly high relative linear velocity between the seed and seed tray during the seed-filling process). This method is based on the stress of the seed group and the limited gear-shaped side space (seed holding space). Kinematic and dynamic analyses of the main states of motion of the seed in the holding space were conducted, and the effects of the stress and movement states on seed-filling performance and automatic seed-cleaning performance were investigated. Through simulation, the velocity fluctuation timings of transverse and longitudinal rotation fillings in the holding space were compared. It was found that sufficient arrangement and a full state-of-motion adjustment on the seed-arranging surface was the key condition to ensuring that seeds fill the type hole by transverse rotation of the seed-filling surface. When seeds were not fully arranged and their state of motion not fully adjusted on the seed-arranging surface, the structural design of the type hole, seed-cleaning surface, and seed-filling surface affected the filling result of longitudinal rotation. The Box–Behnken centre combination method was implemented by setting the friction coefficient μ1 (X1), seed height z (X2), and rotation speed n (X3) as the factors with the qualified index A, leakage index M, and velocity fluctuation ΔH as the evaluation indexes. Multiple regression models and response surface optimisation analyses were performed to obtain the optimal combination of parameters affecting the dibbler seed-filling performance. The results indicated that the most significant factors affecting the A, M, and ΔH, were: z >n > μ1, z >n > μ1, and n >z > μ1. The optimal combination of these parameters was μ1 = 0.463, z = 0.4 kg, and n = 1.88 rps (approximately 9.78 km/h), providing a maximum A = 98.837 %, minimum M = 0.199 %, and ΔH = 0.111 m/s. When ΔH was in the interval of 0.09–0.18 m/s, A was high and stable, whereas M was small, indicating that the seed-filling performance was effective. When μ1 = 0.48, n = 1.5 rps (approximately 7.8 km/h), and z = 0.3 kg, the average values of the bench test were 91.07 % and 6.07 %, consistent with the simulation results. This study contributes significantly toward the research and development of the type hole of precise dibblers, high-speed seed selection method, orderly arrangement, migration, and quantitative separation method of irregular rotary material groups.

Kinematic and dynamic analyses of the front crawl tumble turn in elite female swimmers

Based on a three-dimensional (3D) underwater analysis, the objective of the present study was to identify the biomechanical variables the most associated with turn times in 10 elite female swimmers. For each participant (95.7 ± 2.6% of the 200 m freestyle world record), the best-time turn (from 3 m in to 3 m out, 2.89 ± 0.08 s) was analysed from a three-dimensional (3D) direct linear transformation kinematical reconstruction and the use of a piezoelectric force platform. Bivariate analysis showed that lateral impulse was linked to turn time (r = -0.76, p = 0.01) as well as horizontal velocities at end of the glide and swim resumption (respectively, 1.88 ± 0.2 m·s−1 and 1.48 ± 0.15 m·s−1; r = -0.67 and -0.68; p < 0.05 for both variables). One variable was considered relevant in the best Lasso (Least Absolute Shrinkage and Selection Operator) model: the lateral impulse (8.8 ± 5.1 N·s) during the placement sub-phase.The best tumble turn times were associated with higher lateral impulse during the placement and faster velocities during the underwater actions. The lateral impulse may reflect the swimmers’ longitudinal rotation which was higher for the fastest swimmers.

Decomposition of micromotion at the head-neck interface in total hip arthroplasty during walking

Fretting corrosion as one of the leading causes for failure of modular hip prostheses has been associated with micromotion at head-neck taper junction. Decomposition of micromotion is helpful to promote the development of more realistic experiments investigating failure mechanisms of the head-neck junction in total hip arthroplasty. The aim of this study was to decompose the complex three-dimensional micromotion at the head-neck junction into multiple fundamental modes, including three translational and three rotational components. A three-dimensional finite element model composed of head-neck junction, liner and acetabular cup with a typical 12/14 taper size, as well as the taper mismatch of −4', was developed during walking. The analysis was divided into three procedures: a) the assembly simulation of the head and neck during surgery, b) verification with a simplified axisymmetric model, and c) three-dimensional modelling under normal walking. This study revealed that the main forms of micromotion contained circumferential, longitudinal micromotion and longitudinal rolling toggling, and were closely related to the state of motion. The maximum translational micromotion was predicted to be 10.9 μm during the walking gait, with the predominant modes of the circumferential translation of 9.6 μm, the longitudinal translation of 5.5 μm and the longitudinal rotation of 0.29° along the taper junction. These findings may provide design considerations for further experimental testing about fretting and facilitate the understanding of the fretting mechanisms in hip prostheses.

Implementation of the trajectory controller based on model predictive controlfor unmanned ground vehicle

This paper is devoted to one implementation of a trajectory controller based on model predictive control for an un-manned ground vehicle (UGV). The statement of the problem of autonomous movement along a given trajectory, the assumptions and restrictions adopted are presented. The features of the application of model predictive control for solving the problem are described. A feature of the proposed implementation of the trajectory controller is the use of a linearized chassis dynamics model to predict the position of the robot after a given period of time and control the movement without solving the optimal control problem. To determine the parameters of the dynamic model of the robotic complex, taking into account the drive level, the identification problem was solved, as a result of which two linear models with delay were obtained, describing the dynamics of the longitudinal movement and rotation of the robot. The experiment showed that the obtained models provide high compliance with experimental data, while the robot moves on a surface with a constant coefficient of friction. An algorithm for calculating the predicted position, a block diagram of the trajectory controller and its software implementation are described. The implemented trajectory controller provides autonomous movement of an UGV in an industrial-urban environment or in slightly rugged terrain.

A call to reform undergraduate nursing clinical placements

A call to reform undergraduate nursing clinical placements

Angular velocity around the longitudinal axis in combination with head movements of springboard divers during twisted somersaults

ABSTRACT The ability of springboard divers to perform and control difficult elements with multiple twisted somersaults before entering the water is of great interest for coaches and researchers. In order to produce twists within somersaults, divers use both ‘contact’ and ‘aerial’ techniques. After completing body axes rotations, head movements seem to be important, as they enable visual information in the air. The current study aims at investigating angular velocities around the longitudinal axis in combination with head movements of 13 springboard divers during twisted somersaults. Divers performed forward and backward somersaults with different numbers of half twists. The results revealed maximum longitudinal axis angular velocities between 500°/s and 1300°/s. Moreover, results showed that the use of contact technique was greater in twisted somersaults with backward approaches, and thus higher angular velocities could be achieved. While finishing the twists, head movements in the opposite direction to the longitudinal axis rotation occurred, which allow divers to orient themselves. Twist speeds influenced athletes’ head movements to have greater angles and greater rotational velocities. Therefore, it is concluded that fast head movements are necessary in difficult twisted dives to allow orientation in the short phase between finishing the twist and entering the water surface.

Generation of Sub-Wavelength Sized Optical Needle with Arbitrary Longitudinal Rotation

Generation of Sub-Wavelength Sized Optical Needle with Arbitrary Longitudinal Rotation

Lateral Stability Performance of Articulated Narrow-Track Tractors

A tractor losing lateral stability starts to rollover. It is a matter of fact that tractor lateral rollover accidents are one of the most frequent causes of death and injuries for farmers. Consequently, tractors are fitted with a specific protective structure to minimize the consequences for the driver during the rollover (ROPS). The narrow-track tractor, designed to operate in vineyards and orchards, is a tractor category with a very narrow track width and the risk of rollover is higher. The aim of the study was to evaluate the compact narrow-track tractor types commercially available, designed to mount a cantilever engine in the forward position with effects on the Center of Gravity (CoG) because more than 50% of the tractor weight is loaded on the front axle, and, specifically, the articulated narrow-track tractors where the stability is affected by the pivot point connecting the two tractor bodies. As a consequence of the typical tractor design of articulated tractors, during the steering action the line passing through the front and rear tire contact points on the ground changes, influencing the tractor’s stability. The approach of the research was based on reproducing the lateral stability tractor condition by developing a kinematic model, with the goal to virtually simulate the tractor behavior and to calculate the lateral stability angle for articulated tractors. The innovative contribution of this paper was the tractor articulation joint modeling, assuming a virtual pivot point to reproduce two relatives’ rotations between the front and rear bodies of the tractor: vertical (yaw angle) and longitudinal (roll angle) rotations. The lowest value of the stability angle was 39.3°, measured at −35° yaw angle. The model at the tractor design stage will allow adjusting of the tractor parameters to improve the lateral stability performance.

Motion envelopes: unfolding longitudinal rotation data from walking stick-figures

This work presents Motion Envelopes (ME), a simple method to estimate the missing longitudinal rotations of minimal stick figures, which is based on the spatial-temporal surface traced by line segments that connect contiguous pairs of joints. We validate ME by analyzing the gait patterns of 6 healthy subjects, comprising a total of 18 gait cycles. A strong correlation between experimental and estimated data was obtained for lower limbs and upper arms, indicating that ME can predict their longitudinal orientation in normal gait, hence, ME can be used to complement the kinematic information of stick figures whenever it is incomplete.

Teaching medicine interns minimum geriatrics competencies within a "4 + 2" schedule.

The increased ambulatory training time in an "X + Y" (inpatient + ambulatory) residency schedule affords more opportunities to teach geriatrics principles of care. We describe our internal medicine (IM) residency program's experience in teaching the IM-family medicine (FM) minimum geriatrics competencies (MGC) during a longitudinal geriatrics rotation embedded within interns' yearlong "4 + 2" schedule. Interns spend 1day of the ambulatory block in a geriatrics outpatient setting (Program of All-Inclusive Care for the Elderly, house calls, nursing home), during which geriatrics division faculty members give core didactic seminars. We revamped core seminars to address MGC related to medication management, cognitive health, complex chronic illnesses, end of life care, and ambulatory care. Three consecutive intern cohorts completed anonymous surveys pre- and postrotation, rating their confidence level in MGC addressed by the curriculum on a 5-point Likert scale. On postrotation surveys, they also rated the curriculum's contribution to geriatrics skills enhancement. Interns who completed both surveys (N=22, 92%) reported statistically significant improved confidence ratings on all items, with the greatest point gains seen in performance of functional assessment (1.56), practice of optimal geriatric pharmacotherapy (1.78), and identification of older patients eligible for skilled (1.71) and unskilled home-based services (1.65). They rated geriatrics curricular components as being more helpful than other rotations and conferences in enhancing their geriatric skills. In conclusion, we developed a longitudinal geriatrics curriculum within the context of our "4 + 2" immersion schedule which other programs can easily adapt. Aligning curricular content with the MGC has resulted in interns' improved confidence in several important geriatrics skills.

A non-relativistic limit of M-theory and 11-dimensional membrane Newton-Cartan geometry

We consider a non-relativistic limit of the bosonic sector of eleven-dimensional supergravity, leading to a theory based on a covariant ‘membrane Newton-Cartan’ (MNC) geometry. The local tangent space is split into three ‘longitudinal’ and eight ‘transverse’ directions, related only by Galilean rather than Lorentzian symmetries. This generalises the ten-dimensional stringy Newton-Cartan (SNC) theory. In order to obtain a finite limit, the field strength of the eleven-dimensional four-form is required to obey a transverse self-duality constraint, ultimately due to the presence of the Chern-Simons term in eleven dimensions. The finite action then gives a set of equations that is invariant under longitudinal and transverse rotations, Galilean boosts and local dilatations. We supplement these equations with an extra Poisson equation, coming from the subleading action. Reduction along a longitudinal direction gives the known SNC theory with the addition of RR gauge fields, while reducing along a transverse direction yields a new non-relativistic theory associated to D2 branes. We further show that the MNC theory can be embedded in the U-duality symmetric formulation of exceptional field theory, demonstrating that it shares the same exceptional Lie algebraic symmetries as the relativistic supergravity, and providing an alternative derivation of the extra Poisson equation.

Training the Next Generation of Pediatrician-Advocates: A New Focus on the Inpatient Setting.

Training the Next Generation of Pediatrician-Advocates: A New Focus on the Inpatient Setting.

Creation of a Pharmacy Student Longitudinal Rotation to Expand the Scope of an Antimicrobial Stewardship Program.

Allergy assessments and penicillin skin testing have emerged as a vital intervention for Antimicrobial Stewardship Programs (ASPs). Investment and involvement in such programs by ASPs, however, are often limited due to resources, time, and personnel constraints. Harnessing an underutilized resource, 4th-year advanced pharmacy practice experience (APPE) students, allows for expanded ASP involvement and scope of practice. We aim to outline and provide insight on how 4th-year APPE students serve as an asset to an ASP. Through our novel longitudinal rotation experience, APPE students complete penicillin allergy assessments, patient education, and work alongside a clinical pharmacist to refer patients for penicillin skin testing if appropriate. Students also achieve many of the education standards required by the Accreditation Counsel for Pharmacy Education (ACPE) for graduation within the Doctor of Pharmacy degree while developing a strong foundation in antimicrobial stewardship and gaining invaluable knowledge for their future. The addition of APPE pharmacy students to our ASP has also enabled our program to achieve its goals and expand involvement and reach within our facility.

Modeling intervertebral articulation: The rotule à doigt mechanical joint (RAD) in birds and mammals.

The vertebrate skeleton is composed of articulated bones. Most of the articulations are classically described using mechanical joints, except the intervertebral joint. The aim of this study was to identify a joint model with the same mechanical features as the cervical joints. On the neck vertebrae, six articular surfaces participate in the joint: the cranial part of the centrum and the facets of the two prezygapophyses of a vertebra articulate on the caudal part of the centrum and the two articular facets of the postzygapophyses of the previous vertebra. We used the intervertebral joints of the birds neck to identify the mechanical joint representing intervertebral linkage. This link was described in the literature as a joint allowing two or three rotations and no translation. These features correspond to the rotule à doigt (RAD) joint, a ball and socket joint with a pin. We compared the RAD joint to the postaxial intervertebral joints of the avian neck and found it a suitable model to determine the geometrical features involved in the joint mobility. The difference in the angles of virtual axes linking the geometrical center of the centrum to the zygapophysis surfaces determines the mean dorsoventral flexion of the joint. It also helps to limit longitudinal rotation. The orientation of the zygapophysis surfaces determines the range of motion in both dorsoventral and lateral flexion. The overall system prevents dislocation. The model was validated on 13 joints of a vulture neck and 11 joints of a swallow neck and on one joint (C6-C7) in each of three mammal species: the wolf (Canis lupus), mole (Talpa europaea), and human (Homo sapiens). The RAD mechanical joint was found in all vertebral articulations. This validation of the model on different species shows that the RAD intervertebral joint model makes it possible to extract the parameters that guide and limit the mobility of the cervical spine from the complex shape of the vertebrae and to compare them in interspecific studies.

Vertical force generation of a vectorial thruster that employs a rigid flapping panel

The vertical force generation and flow features of a flapping panel that employs combined motion of horizontal oscillation, longitudinal rotation, and leading-edge-based pitching motion were investigated numerically. The sole vertical force generation is realized by combining the horizontal oscillation and longitudinal rotation, while the vertical force and forward thrust are obtained simultaneously by employing the combined motion of the horizontal oscillation, longitudinal rotation, and pitching motion about the leading edge of the panel. The effects of the phase shift (Ψ) of the longitudinal rotation and the amplitudes of the longitudinal rotation and pitching motion are investigated and discussed, respectively. Results show that the phase shift determines the instantaneous attitude of the panel and influences the directions of the instantaneous generated forces and thus plays an important role in the vertical force generation. The panel could generate stable forward thrust while maintaining the pitching motion constant and adjusting the longitudinal rotation amplitude, and in the meantime, the vertical force increases linearly with the rotation amplitude. On the other hand, the vertical force may change to the opposite direction when the longitudinal rotation is kept constant and the pitching amplitude is adjusted. The results of the current research show the potential of employing these kinds of combined motions to fish-tail-mimic propulsors of robotic fishes that pursue high maneuverability.

Is torso twist production the primary role of the torso muscles in front crawl swimming?

ABSTRACT The torso muscles play important roles in longitudinal rotation between the upper and lower torso on land but demands on these muscles at different swimming speeds and their role in torso twist in front crawl remains unclear. We aimed to compare torso muscle activity at different front crawl speeds and to assess the relationships between torso muscle activity and torso twist. Three-dimensional kinematics and torso muscle EMG data were collected from 15 male swimmers during middle-distance and sprint front crawl. Internal oblique, external oblique, and rectus abdominis, but not erector spinae, activities were greater at sprint than middle-distance pace. Sprint swimmers are likely to benefit from focusing training on the abdominal muscles. Cross-correlation peak coefficients between muscle activity and torso twist occurred with 517–775 and 400–600 ms lag at middle-distance and sprint paces (respectively). These lags are beyond the torso muscle electromechanical delay (~220 ms) and are too long for these muscles to produce movement changes. Further, peak coefficients coincided with both positive and negative shifts, indicating that muscle activity did not always precede kinematic changes. The torso muscles are therefore likely to play a greater role in maintaining stability and controlling posture in front crawl than producing torso twist.

It's Not You, It's Me: Learning to Navigate the Patient-Physician Relationship.

In this essay, a medical student details how she struggled to let go of a patient with whom she connected throughout the patient's pregnancy during her second year of medical school. Although she learned in her preclinical "doctoring" courses how to build quick connections with patients, such training did not delve into how to manage meaningful, emotionally complex connections that may form with patients during longitudinal rotations or, as in this case, extracurricular activities. While primary care physicians may have decades of practice managing evolving longitudinal relationships, medical students who form strong connections with patients are just learning what it means to navigate those relationships, some of which come to an end. Reflecting on the end of this particular relationship helped the author appreciate the power of the longitudinal physician-patient relationship and taught her that taking care of patients also requires taking care of one's self.

Availability of Naloxone in 2 Underserved Urban Communities in Georgia.

In 2016, unintentional injuries became the third leading cause of death in the United States. In 2018, 54% of 103 672 unintentional injury deaths were due to drug overdoses among adults 19 to 64 years of age. In Georgia, opioid overdose deaths continued to increase, despite a 2014 state law for naloxone use to prevent deaths, and a 2017 amendment for more widespread community use without a prescription. Given these policies, naloxone availability in pharmacies in underserved communities remains unclear. Our objective is to explore naloxone availability in such communities. Three Public Health and Preventive Medicine residents during a social-cultural-behavioral longitudinal rotation conducted interviews of 9 community pharmacists. Several themes emerged: more education was needed, and naloxone was available only by prescription in certain pharmacies or in limited amounts. Additional assessments among community members and sectors can examine the extent to which policies to expand naloxone availability and accessibility are implemented, including reduced naloxone costs.