Translation Distance Research Articles

Computer-aided design for analyzing the influence of anteroposterior translation on artificial knee joint stability

The Anteroposterior translational distance (AP) is one of the parameters used to assess stability in the artificial knee joint (AKJ), this translation is influenced by the posterior tibial slope (PTS) and the type of implant. The tibiofemoral contact of the medial pivot system on the AKJ provides satisfaction to the patient, especially for activities that require a deep flexion angle. Asians, especially Indonesians, need a deep flexion angle between 150° and 165° for religious, social, and cultural activities, while patients using artificial knee joint difficulty doing activities with this flexion angle. On the other hand, the development of implant designs with high flexion angles causes a decrease instability because the anteroposterior translation is too large, therefore it is necessary to analyze. This research aims to analyze the stability of AKJ with measurement of AP translation based on computer aided design (CAD) approach. The study used standard existing implants as physical models to develop. The process of reconstruction of physical models begins from surface digitization, surface processing, curve processing, and component improvements. In this study has been successfully tested the stability of AKJ design against AP translation, the results show the level of stability is at the safe limit of medical standards, as well as within the threshold of arthrometers data, so it is expected to provide comfort for religious, social and cultural activities for Asian people, especially in Indonesia.

Band gap of silicon photonic crystal with square-lattice and windmill-shaped defects

A new type of 2D square-lattice photonic crystal with different windmill-shaped defects is proposed. Based on the plane wave expansion method and super cell theory, the band gaps of defect models are numerically analyzed according to the symmetry. We aim at further reducing the defect symmetry of photonic crystals compared to previous studies and researching the effect of translation and rotation of different windmill-shaped defect structures on the transverse magnetic (TM) band gap. The results reveal that the translation distance of defects brings great impacts on the band gap of 2D square-lattice photonic crystals and the width of the TM band gap can be further expanded after rotating on the basis of translation. In addition, we discovery that the band gap of the model with even-numbered fan-shaped defects is wider than that of the model with odd-numbered fan-shaped defects. Among the five different defect models (three-wings, four-wings, five-wings, six-wings, rotating-cross), the four-wing windmill defect model produces the largest band gap, which reaches 5.307 × 10−2 (ɷa/2πc). This research is helpful to understand the band gap characteristics of photonic crystals, which will contribute to the design of photonic crystal devices.

Design and realization of two-dimensional beam steering actuated by dielectric elastomer

A two-dimensional beam steering device is an essential optical element for many applications, such as free-space optical communications, light detection and ranging, and microscopy. The purpose of the paper is to develop a two-dimensional beam steering device with a simple structure and a large beam steering angle. The principle of beam steering is based on the decentred lens. The decentred lens is placed on the center of the dielectric elastomer and the movement of the decentred lens is actuated by the dielectric elastomer The dielectric elastomer is divided into four quadrants and the top and bottom surfaces of the four quadrants of dielectric elastomer are coated by compliant electrodes. Through applying different voltages on the four quadrants, the decentred lens can move and the beam is steered in a two-dimensional direction. We develop a prototype and carried out imaging experiments to verify the proposed beam steering method. The experimental results show that the maximum translation distance of the decentred lens is 1.496 mm at an actuation voltage of 5 kV. The function of two-dimensional beam steering is realized and the maximum beam steering angle of the device is 11.98°. Such a two-dimensional beam steering device promises a potential solution in various beam steering systems.

Forces and translation distance during an inferior glide of the shoulder in asymptomatic individuals measured with the novel pliance glove and ultrasound imaging

BackgroundThere has been limited research on how the variance of force affects manual therapy outcomes and what the best practices should be. No specific force threshold necessary to achieve a predetermined translational distance within the joint has been quantified within the literature. PurposeTo quantify the amount of force necessary to perform an inferior glide to the glenohumeral joint and reach to end range. A secondary aim was to determine the impact of co-variables, such as gender, height, weight, and age, on the amount of force required to translate the humeral head within the glenohumeral joint. MethodsA convenience sample of 64 healthy subjects were recruited. Musculoskeletal ultrasound imaging using the GE LogiQe was used to measure the translation of the humeral head. The manipulation force was measured using the novel pliance glove device and software. The ANOVA was used to determine if there was a difference in translation distance and force between trials. The Pearson's correlation was used to correlate translation and force and between covariables. ResultsThere was no significant difference in translation distance between trials (p = .14). There was no significant difference in the mean force for this translation (p = .45). There was a poor correlation between age and force (r = 0.28) and weight and force (r = 0.12). ConclusionAn average force of 14.27 N (n = 61) was needed to displace the humeral head to reach end range. This was the first study using the combination of a flexible force sensor technology and real-time ultrasound imaging to measure humeral head translation.

HyperSoRec: Exploiting Hyperbolic User and Item Representations with Multiple Aspects for Social-aware Recommendation

Social recommendation has achieved great success in many domains including e-commerce and location-based social networks. Existing methods usually explore the user-item interactions or user-user connections to predict users’ preference behaviors. However, they usually learn both user and item representations in Euclidean space, which has large limitations for exploring the latent hierarchical property in the data. In this article, we study a novel problem of hyperbolic social recommendation, where we aim to learn the compact but strong representations for both users and items. Meanwhile, this work also addresses two critical domain-issues, which are under-explored. First, users often make trade-offs with multiple underlying aspect factors to make decisions during their interactions with items. Second, users generally build connections with others in terms of different aspects, which produces different influences with aspects in social network. To this end, we propose a novel graph neural network (GNN) framework with multiple aspect learning, namely, HyperSoRec. Specifically, we first embed all users, items, and aspects into hyperbolic space with superior representations to ensure their hierarchical properties. Then, we adapt a GNN with novel multi-aspect message-passing-receiving mechanism to capture different influences among users. Next, to characterize the multi-aspect interactions of users on items, we propose an adaptive hyperbolic metric learning method by introducing learnable interactive relations among different aspects. Finally, we utilize the hyperbolic translational distance to measure the plausibility in each user-item pair for recommendation. Experimental results on two public datasets clearly demonstrate that our HyperSoRec not only achieves significant improvement for recommendation performance but also shows better representation ability in hyperbolic space with strong robustness and reliability.

Mud volcanoes and dissolution structures as kinematic markers during salt tectonic deformation

AbstractThe recognition of linear trails of fluid escape pipes that have been deformed by salt flow have recently been suggested to offer a novel approach to reconstructing the internal kinematics of thick salt sequences deforming under gravity. These deformed pipes constrain a number of key parameters for salt tectonic analysis including the salt flow direction, translation distance of the top salt and overburden, the internal flow profile and from the flow velocity, the bulk viscosity of the salt. Here we interpret and characterise two previously unrecognised large‐scale strain markers within a salt sequence that may be equally as valuable as the deformed pipes for constraining salt flow. This study is based on the interpretation of a ca. 4,600 km2 3D seismic survey from the outer slope of the Nile Cone, offshore Egypt, located at the boundary between the extensional and translational domains of the deformed marginal region of the Messinian salt basin. We mapped five deformed pipe trails that allow us to constrain the average flow velocity of the top salt, at ca. 2 mm/yr over the past 2–3 Myrs. The salt flowed in a basinward NW/NNW direction away from the basin margin. In addition, we mapped two large (ca. 2 km diameter) salt dissolution depressions formed by subjacent dissolution of the evaporites. These are presently located down the salt flow direction of a large remnant erosional high at the base of the salt, and in the general alignment of one of the pipe trails. We therefore argue that this dissolution structure most likely formed by fluid venting from the base salt high, and as such can be used to measure translation direction, distance and average velocity. The second of the two novel kinematic indicators requires mapping of genetically connected mud volcanoes and their depletion zones. The study area contains over 400 individual mud volcanoes that are sourced from beneath the salt and erupted from the Early Pliocene to Recent. A subset of these, extruded at or near to the present day seafloor, have well imaged pre‐salt depletion zones vertically beneath the erupted volcanic cones. A smaller subset, typically buried Early Pliocene extrusions, is found to have volcanic cones that are systematically offset laterally from their corresponding depletion zones, with an offset direction and distances closely matched with other kinematic markers. Hence we suggest that mud volcanic plumbing systems can provide another independent kinematic marker from which to infer salt flow regime.

Drug repositioning against COVID-19: a first line treatment

COVID-19 disease caused by the SARS-CoV-2 virus has shaken our health and wealth foundations. Although COVID-19 vaccines will become available allowing for attenuation of disease progression rates, distribution of vaccines can create other challenges and delays. Hence repurposed drugs against SARS-CoV-2 can be an attractive parallel strategy that can be integrated into routine clinical practice even in poorly-resourced countries. The present study was designed using knowledge of viral pathogenesis and pharmacodynamics of broad-spectrum antiviral agents (BSAAs). We carried out the virtual screening of BSAAs against the SARS-CoV-2 spike glycoprotein, RNA dependent RNA polymerase (RdRp), the main protease (Mpro) and the helicase enzyme of SARS-CoV-2. Imatinib (a tyrosine kinase inhibitor), Suramin (an anti-parasitic), Glycyrrhizin (an anti-inflammatory) and Bromocriptine (a dopamine agonist) showed higher binding affinity to multiple targets. Further through molecular dynamics simulation, critical conformational changes in the target protein molecules were revealed upon drug binding which illustrates the favorable binding conformations of antiviral drugs against SARS-CoV-2 target proteins. The resulting drugs from the present study in combination and in cocktails from the arsenal of existing drugs could reduce the translational distance and could offer substantial clinical benefit to decrease the burden of COVID-19 illness. This also creates a roadmap for subsequent viral diseases that emerge. Communicated by Ramaswamy H. Sarma

Experimental validation of a new technique for the assessment of posterior tibial translation (ABC angle) after posterior cruciate ligament rupture

BackgroundThe aim of this cadaver study was to evaluate an original technique for measuring posterior tibial translation based on an angle value instead of a distance value, with and without posterior stress application. It was hypothesized that an angle measurement of the posterior tibial translation would confirm the presence of a PCL tear with the knee flexed and completely extended.MethodUsing fresh cadavers, a set of strict lateral views were taken by fluoroscopy with the knee at 0°, 45° and 90° flexion on the intact knee and after transecting the PCL. The primary endpoint was the change in the posterior translation measured using a new technique, the ABC angle. This measurement was compared to the conventional posterior translation distance measurement with and without a posterior stress placed on the knee.ResultsApplication of a posterior stress revealed clear changes in posterior translation after PCL transection with the knee at 0° for the angle technique and at 45° and 90° for the two techniques (p < 0.05). Contrary to the reference method, the ABC angle method found a statistically significant difference in posterior translation with the knee in extension.ConclusionOur technique provides a reliable radiographic measurement of posterior translation with the knee in extension, which should make it easier to acquire radiographs in patients who have pain with knee flexion. This angular measurement also has the advantage of not needing length calibration contrary to the reference technique.Level of evidenceIV

High initial graft tension increases external tibial rotation on the axial plane after anatomical anterior cruciate ligament reconstruction.

The purpose of this study was to clarify the effects of applying different amounts of initial graft tension on the femorotibial positional relationship on the axial plane after anatomical ACL reconstruction. Eighty patients who underwent isolated ACL reconstructions using bone-patellar tendon-bone grafts were included in this study. In 40 of the 80 patients, the grafts were fixed at full knee extension with maximum manual force (high graft tension; Group H), whereas in the other 40 patients, the grafts were fixed at full knee extension with force of 80N (low graft tension; Group L). One week postoperatively, all patients underwent computed tomography (CT) on bilateral knee joints with knee extension. The femorotibial positional relationship in axial CT images were retrospectively evaluated. Side-to-side differences (the surgical side minus the unaffected side) were calculated in these variables. The side-to-side differences in anterior tibial translation distances were - 1.8 ± 2.1mm in Group H and - 1.9 ± 2.0mm in Group L, with no significant difference between the two groups. The side-to-side differences in tibial lateral shifts were - 0.2 ± 1.5mm in Group H and 0.0 ± 1.4mm in Group L, with no significant difference between the two groups. The side-to-side differences in tibial external rotation angles were 2.7 ± 4.5° in Group H and 0.3 ± 3.3° in Group L, with a significant difference between the two groups (P < 0.01). Applying high initial graft tension (maximum manual force) resulted in the external rotation of the tibia against the femur just after anatomical ACL reconstruction. In contrast, applying low initial graft tension (80N at full knee extension) did not change the femorotibial rotational relationship.

Demonstration of central conduction time and neuroplastic changes after cervical lordosis rehabilitation in asymptomatic subjects: a randomized, placebo-controlled trial

A randomized controlled study was conducted to evaluate the effect of rehabilitation of the cervical sagittal configuration on sensorimotor integration and central conduction time in an asymptomatic population. Eighty (32 female) participants with radiographic cervical hypolordosis and anterior head translation posture were randomly assigned to either a control or an experimental group. The experimental group received the Denneroll cervical traction while the control group received a placebo treatment. Interventions were applied 3 × per week for 10 weeks. Outcome measures included radiographic measured anterior head translation distance, cervical lordosis (posterior bodies of C2–C7), central somatosensory conduction time (latency) (N13–N20), and amplitudes of potentials for spinal N13, brainstem P14, parietal N20 and P27, and frontal N30. Outcomes were obtained at: baseline, after 10 weeks of intervention, and at 3 months follow up. After 10 weeks and 3-months, between-group analyses revealed statistically significant differences between the groups for the following measured variables: lordosis C2–C7, anterior head translation, amplitudes of spinal N13, brainstem P14, parietal N20 and P27, frontal N30 potentials (P < 0.001), and conduction time N13–N20 (P = 0.004). Significant correlation between the sagittal alignment and measured variables were found (P < 0.005). These findings indicate restoration of cervical sagittal alignment has a direct influence on the central conduction time in an asymptomatic population.

Directly observing the skew angle of a Poynting vector in an OAM carrying beam via angular diffraction.

A new, to the best of our knowledge, method for directly measuring the skew angle of a Poynting vector of optical vortices is reported in this Letter. We design an incomplete optical vortex phase to mimic the occlusion of actual objects on the light path. By capturing the intensity cross section of the incomplete vortex field, the energy flow can be observed directly; thus, the skew angle of the Poynting vector can be directly measured. In this Letter, we measure the skew angle of the Poynting vector with an error less than 3%. Further, the work in this Letter may provide a new way to sense the translational distance and measure the topological charge of the optical vortex.

Dynamic Acoustic Levitator Based On Subwavelength Aperture Control.

Acoustic levitation provides a means to achieve contactless manipulation of fragile materials and biological samples. Most acoustic levitators rely on complex electronic hardware and software to shape the acoustic field and realize their dynamic operation. Here, the authors introduce a dynamic acoustic levitator that is based on mechanically controlling the opening and (partial) closing of subwavelength apertures. This simple approach relies on the use of a single ultrasonic transducer and is shown to permit the facile and reliable manipulation of a variety targets ranging from solid particles, to fluid and ferrofluidic drops. Experimental observations agree well with numerical simulations of the Gor'kov potential. Remarkably, this system even enables the generation of time‐varying potentials and induces oscillatory and rotational motion in the levitated objects via a feedback mechanism between the trapped object and the trapping potential. This is shown to result in long distance translation, in‐situ rotation and self‐modulated oscillation of the trapped particles. In addition, dense ferrofluidic droplets are levitated and transformed inside the levitator. Controlling subwavelength apertures opens the possibility to realize simple powerful levitators that nevertheless allow for the versatile dynamic manipulation of levitated matter.

X-ray source translation based computed tomography (STCT).

Micro computed tomography (µCT) allows the noninvasive visualization and 3D reconstruction of internal structures of objects with high resolution. However, the current commercial µCT system relatively rotates the source-detector or objects to collect projections, referred as RCT in this paper, and has difficulties in imaging large objects with high resolutions because fabrication of large-area, inexpensive flat-panel detectors remains a challenge. In this paper, we proposed a source translation based CT (STCT) for imaging large objects with high resolution to get rid of the limitation of the detector size, where the field of view is primarily determined by the source translation distance. To compensate for the deficiency of incomplete data in STCT, we introduced multi-scanning STCT (mSTCT), from which the projections theoretically meet the conditions required for accurate reconstructions. Theoretical and numerical studies showed that mSTCT has the ability to accurately image large objects without any visible artifacts. Numerical simulations also indicated that mSTCT has a potential capability to precisely image the region of interest (ROI) inside objects, which remains a challenge in RCT due to truncated projections. In addition, an experimental platform for mSTCT has been established, from which the 2D and 3D reconstructed results demonstrated its feasibility for µCT applications. Moreover, STCT also has a great potential for security inspection and product screening by using two perpendicular STCTs, with advantages of low-cost equipment and high-speed examination.

Location-Sensitive Embedding for Knowledge Graph Embedding

<p indent=0mm>Knowledge graph embedding maps the discrete symbolic entities and relations into continuous low-dimensional space, enabling the downstream task (e.g., inference, knowledge graph completion and etc.) to be carried on in an algebraic manner. Roughly speaking, there are two main-streams towards knowledge graph embedding, translational distance models and semantic matching models. The learning bottleneck of the former caused by special graph structures is analyzed. And it is found out that translational distance models are to be blamed for treating head and tail entities from a same viewpoint. So, a location-sensitive embedding (LSE) model is proposed. Unlike previous models, it just transforms the head entity with relational-specific mapping. And it models relation as a general linear transformation instead of a translational operator. Its representation capacity and the relationship to current models are theoretically analyzed. Also, to make it efficient, the model is simplified by assuming a diagonal matrix for transformation, forming a simplified model LSE<italic>_d</italic>. It is evaluated that the proposed model on four large-scale knowledge graph datasets for link prediction task. Experiments have shown that the proposed model achieves highest, or at least competitive, performance compared with the state-of-the-art models.

High Pitch Helical CT Reconstruction.

To avoid severe limited-view artifacts in reconstructed CT images, current multi-row detector CT (MDCT) scanners with a single x-ray source-detector assembly need to limit table translation speeds such that the pitch p (viz., normalized table translation distance per gantry rotation) is lower than 1.5. When , it remains an open question whether one can reconstruct clinically useful helical CT images without severe artifacts. In this work, we show that a synergistic use of advanced techniques in conventional helical filtered backprojection, compressed sensing, and more recent deep learning methods can be properly integrated to enable accurate reconstruction up to p=4 without significant artifacts for single source MDCT scans.

The Adoption Challenge: An Analysis of Research Methods in JIBS

This study introduces the concepts of translational distance and complexity distance to explain challenges to adoption of research methods in JIBS. We examine three analytical techniques and data collection approaches: (1) Heckman models, (2) ethnographic studies, and (3) data collection equivalence procedures in survey-based research. We note that progress has been made to reduce translational and complexity distance for analytical techniques. However, concerns remain for data collection equivalence and ethnography as IB scholars are using increasingly advanced analytical techniques on less credible data.

Spring ligament insufficiency and hallux valgus as an independent risk factors for first ray instability

IntroductionFirst ray instability (FRI) arising from failed plantar/interosseous ligaments is strongly associated with planovalgus, leading to synovitis and deformity. Our hypothesis is that proximal spring ligament insufficiency (SLI) drives secondary FRI in the absence of hallux valgus (HV) and may be an independent risk factor. MethodsPatients with FRI, screened by Klaue’s test, were recruited. Patients’ normal contralateral feet with previous radiographs were included as controls. First ray dorsal translation was measured with a digital Klauemeter. Spring ligament integrity was assessed using lateral translation distance as an indirect measure of spring ligament strain. Intermetatarsal angle and hallux valgus angle were recorded to classify the severity of HV. ResultsSeventy feet included, 54 had symptomatic FRI and 16 were asymptomatic contralateral feet included as control. Twenty-three feet had moderate/severe HV and 47 had mild/normal HV. Moderate/severe HV was associated with FRI (OR, 10.31; p = 0.029). Forty-five feet with SLI had a strong association with FRI (OR, 100.7; p < 0.0001). SLI without moderate/severe HV was the most prevalent group (31/54), followed by SLI with moderate/severe HV, 29.63% (16/54). Moderate/severe HV without SLI was prevalent in 11.1% (6/54) and 1.85% (1/54) had no SLI or moderate/severe HV. In a multivariate logistic regression analysis model, both SLI and severe/moderate HV were independent predictors of FRI. ConclusionThis is the first study that links SLI and HV as independent risk factors to FRI. 98.15% of FRI can be attributed to SLI, HV or both. First ray instability may allude to the strong presence of spring ligament insufficiency in the absence of hallux valgus. Level of evidenceLevel III, retrospective cohort study.

End-to-End 6DoF Pose Estimation From Monocular RGB Images

We present a conceptually simple framework for 6DoF object pose estimation, especially for autonomous driving scenarios. Our approach can efficiently detect the traffic participants from a monocular RGB image while simultaneously regressing their 3D translation and rotation vectors. The proposed method 6D-VNet, extends the Mask R-CNN by adding customised heads for predicting vehicle's finer class, rotation and translation. It is trained end-to-end compared to previous methods. Furthermore, we show that the inclusion of translational regression in the joint losses is crucial for the 6DoF pose estimation task, where object translation distance along longitudinal axis varies significantly, e.g., in autonomous driving scenarios. Additionally, we incorporate the mutual information between traffic participants via a modified non-local block to capture the spatial dependencies among the detected objects. As opposed to the original non-local block implementation, the proposed weighting modification takes the spatial neighbouring information into consideration whilst counteracting the effect of extreme gradient values. We evaluate our method on the challenging real-world Pascal3D+ dataset and our 6D-VNet reaches the 1st place in ApolloScape challenge 3D Car Instance task (Apolloscape, 2018), (Huang et al., 2018).

C-H⋯O contacts in the crystal structure of 1,3-di-thiane 1,1,3,3-tetra-oxide.

The crystal structure of 1,3-di-thiane 1,1,3,3-tetra-oxide, C4H8O4S2, has been determined to examine the inter-molecular C-H⋯O hydrogen bonds in a small mol-ecule with highly polarized hydrogen atoms. The crystals are monoclinic, space group Pn, with a = 4.9472 (5), b = 9.9021 (10), c = 7.1002 (7) Å and β = 91.464 (3)° with Z = 2. The mol-ecules form two stacks parallel to the a axis with the molecules being one a translation distance from each other. This stacking involves axial hydrogen atoms on one mol-ecule and the axial oxygen atoms on the adjacent mol-ecule in the stack. None of these C-H⋯O contacts is particularly short (all are > 2.4 Å). The many C-H⋯O contacts between the two stacks involve at least one equatorial hydrogen or oxygen atom. Again, no unusually short contacts are found. The whole crystal structure basically consists of a complex network of C-H⋯O contacts with no single, linear C-H⋯O contacts, only contacts that involve two (bifurcated), and mostly three or four neighbors.

On continuity of drifts of the mapping class group

A random walk on a countable group $G$ acting on a metric space $X$ gives a characteristic called the drift which depends only on the transition probability measure $\mu$ of the random walk. The drift is the `translation distance' of the random walk. In this paper, we prove that the drift varies continuously with the transition probability measures, under the assumption that the distance and the horofunctions on $X$ are expressed by certain ratios. As an example, we consider the mapping class group $\mathrm{MCG}(S)$ acting on the Teichmuller space. By using north-south dynamics, we also consider the continuity of the drift for a sequence converging to a Dirac measure. As an appendix, we prove that the asymptotic entropy of the random walks on $\mathrm{MCG}(S)$ varies continuously.