A CT-based technique to predict optimal projection for self-expanding TAVI in patients with different aortic valve anatomies

Background Optimal projection is essential for valve deployment during transcatheter aortic valve implantation (TAVI). The purpose of this study was to propose an approach to predict optimal projection in TAVI candidates with different aortic valve anatomies. Methods 331 patients undergoing self-expanding TAVI were included and the so-called non-coronary cusp (NCC)-parallel technique was utilized, which generated the predicted projection by connecting NCC commissures on the transverse plane on the pre-procedural computed tomography images. Results 37.8% of the study cohort were bicuspid aortic valve (BAV) patients. Around 80% of both NCC-parallel views and final views were in the right anterior oblique (RAO) and caudal (CAU) quadrant. There was less than 5° change required from the NCC-parallel view to the final implanted view in 79% of tricuspid aortic valve (TAV) patients but only in 27% (13/48) of type 0 BAV patients with coronary arteries originated from the different cusps. After excluding the above mentioned BAV patients, 62.3% (48/77) of BAV patients needed less than 5° change to achieve optimal projection and only in 8 patients, the angular change was larger than 10° in either left/right anterior oblique or cranial/caudal direction. Conclusions The NCC-parallel technique provides reliable prediction for optimal projection in self-expanding TAVI in all TAV and most BAV patients, with a vast majority of views in the RAO and CAU quadrant.

Computational analyses decipher the primordial folding coding the 3D structure of the beetle horn

The beetle horn primordium is a complex and compactly folded epithelial sheet located beneath the larval cuticle. Only by unfolding the primordium can the complete 3D shape of the horn appear, suggesting that the morphology of beetle horns is encoded in the primordial folding pattern. To decipher the folding pattern, we developed a method to manipulate the primordial local folding on a computer and clarified the contribution of the folding of each primordium region to transformation. We found that the three major morphological changes (branching of distal tips, proximodistal elongation, and angular change) were caused by the folding of different regions, and that the folding mechanism also differs according to the region. The computational methods we used are applicable to the morphological study of other exoskeletal animals.

Perception of urban subdivisions in pedestrian movement simulation

The perception of urban subdivisions, deriving from regionalisation processes and the identification of separating elements (barriers), has proven to dynamically shape peoples’ cognitive representations of space and route choice behaviour in cities. However, existing Agent-Based Models (ABMs) for pedestrian simulation have not accounted for these particular cognitive mapping processes. The aim of this paper is to explore the behaviour of pedestrian agents endowed with knowledge about urban subdivisions. Drawing from literature in spatial cognition, we adapted a region-based route choice model, which contemplates a high- and a local planning level, and advanced a barrier-based route choice model, wherein the influence of separating elements is manipulated. Finally, we combined these two approaches in a region-barrier based model. The patterns emerging from the movement of agents employing such approaches were examined in the city centres of London and Paris. The introduction of regions in the routing mechanisms reduced the unbalanced concentration of agents across the street network brought up by the widely employed least cumulative angular change model (-.08 Gini coefficient). The inclusion of barriers further raised the dispersal of the agents through secondary roads, while leading agents to walk along waterfronts and across parks; it also yielded a more regular usage of pedestrian roads. Moreover, the region- and the region-barrier based routes showed deviation ratio values from the road distance shortest path (region-based: 1.18 London, 1.16 Paris, region-barrier based: 1.43 London, 1.33 Paris) consistent with empirical observations from pedestrian behaviour research. A further evaluation of the model with macro-level observational data may enhance the understanding of pedestrian dynamics and help tuning the interplay amongst urban salient elements at the agent level. Yet, we consider the movement flows arising from our current implementation insightful for assessing the distribution of pedestrians and testing possible interventions for the design of legible and walkable spaces.

Detecting sleep in free-living conditions without sleep-diaries: a device-agnostic, wearable heart rate sensing approach

Study Objectives: The rise of multisensor wearable devices offers a unique opportunity for the objective inference of sleep outside laboratories, enabling longitudinal monitoring in large populations. To enhance objectivity and facilitate cross-cohort comparisons, sleep detection algorithms in free-living conditions should rely on personalized but device-agnostic features, which can be applied without laborious human annotations or sleep diaries. We developed and validated a heart rate-based algorithm that captures inter- and intra-individual sleep differences, does not require human input and can be applied in free-living conditions. Methods: The algorithm was evaluated across four study cohorts using different research- and consumer-grade devices for over 2,000 nights. Recording periods included both 24-hour free-living and conventional lab-based night-only data. Our method was systematically optimized and validated against polysomnography and sleep diaries and compared to sleep periods produced by accelerometry-based angular change algorithms. Results: We evaluated our approach in four cohorts comprising two free-living studies with detailed sleep diaries and two PSG studies. In the free-living studies, the algorithm yielded a mean squared error (MSE) of 0.06 to 0.07 and a total sleep time deviation of -0.60 to -14.08 minutes. In the laboratory studies, the MSE ranged between 0.06 and 0.10 yielding a time deviation between -23.23 and -33.15 minutes. Conclusions: Our results suggest that our heart rate-based algorithm can reliably and objectively infer sleep under longitudinal, free-living conditions, independent of the wearable device used. This represents the first open-source algorithm to leverage heart rate data for inferring sleep without requiring sleep diaries or annotations.

Computational analyses decipher the primordial folding coding the 3D structure of the beetle horn

The beetle horn primordium is a complex and compactly folded epithelial sheet located beneath the larval cuticle. Only by unfolding the primordium the complete 3D shape of the horn appears, suggesting that the morphology of beetle horns is coded in the primordial folding pattern. To decipher the folding pattern, we have developed a method to manipulate the primordial local folding, reproduced it on a computer, and clarified the contribution of the folding of each primordium region to transformation. We found that the three major morphological changes (branching of distal tips, proximodistal elongation, and angular change) were caused by the folding of different regions, and that the folding mechanism was also different depending on the region. The computational methods we used are applicable to the morphological study of other exoskeletal animals.

A Pristine Approach for the Prominent Premaxilla in Bilateral Cleft Lip and Palate (BCLP) Cases

Objective: The neonate premaxilla in bilateral cleft lip and palate is often protruding and displaced laterally. Surgeons prefer the premaxilla to be repositioned and centralized to allow a tension-free primary lip repair. This report describes the fabrication of a premaxillary bonnet appliance with silicone material and its successful use in 2 cases of bilateral cleft lip and palate (BCLP). Patients, Participants: Two male BCLP patients of ages 34 days and 10 days, respectively. Interventions: Nonsurgical repositioning of the premaxillary segment using silicone cup–bonnet appliance. Results: The duration of active treatment by silicone appliance was 36 days in case 1 and 75 days in case 2. The retention period was 2 months and 3 months, respectively. The appliance made of room temperature vulcanizing (RTV) silicone is flexible and softer in comparison to the rigid conventional acrylic appliance and is therefore almost atraumatic. A gentler appliance resulted in enhanced compliance and acceptance by the neonates. There was a noticeable change in the position of the discernible asymmetric premaxilla. Analysis of frontal facial photographs revealed an angular change in the position of the premaxilla (C) by 12° in case 1 and 6° in case 2 in reference to the midfacial plane. Conclusion: This silicone appliance provides enhanced compliance and improved retention compared to acrylic appliance since it is a more gentle, flexible, and less traumatic alternative to a rigid acrylic appliance. Further, the RTV silicone appliance can be 3-dimensionally printed for better accuracy following intraoral scanning and thus eliminating the need for impression making in cleft newborns.

An Anisotropic Auxetic 2D Metamaterial Based on Sliding Microstructural Mechanism

A new 2D microstructure is proposed herein in the form of rigid unit cells, each taking the form of a cross with two opposing crossbars forming slots and the other two opposing crossbars forming sliders. The unit cells in the microstructure are arranged in a rectangular array in which the nearest four neighboring cells are rotated by 90° such that a slider in each unit cell is connected to a slot from its nearest neighbor. Using a kinematics approach, the Poisson’s ratio along the axes of symmetry can be obtained, while the off-axis Poisson’s ratio is obtained using Mohr’s circle. In the special case of a square array, the results show that the Poisson’s ratio varies between 0 (for loading parallel to the axes) and −1 (for loading at 45° from the axes). For a rectangular array, the Poisson’s ratio varies from 0 (for loading along the axes) to a value more negative than −1. The obtained results suggest the proposed microstructure is useful for designing materials that permit rapid change in Poisson’s ratio for angular change.

OPTIMASI DESAIN STENT PLA MENGGUNAKAN METODE RESPONSE SURFACE (RSM) UNTUK MEMPEROLAH FLEKSIBILITAS TERBAIK

The stent installation is one of cardiovascular disease treatments which is selected the most to handle patients with blood vessel disease. As the demand for stents increases, more researches are aimed at developing them. This study aims to obtain the optimal link design to produce the best flexibility to the change of stent angle with minimum stress so as not to injure blood vessel plaque. In this study, the stents are polymer stent with different types of links made with PLA materials with strut mirror (S><) design. The study was conducted on two stent configurations, namely crimped and expanded to determine the ability of angular change and maximum stress experienced by both when bending moment applied. The bending moment test was done through simulation based on finite element method in software Abaqus 6.14. The simulation results were then used as a model-making reference to determine the desired optimization design using the help of Minitab 18 software based on the response surface method. The results of this study indicate that the best optimal flexibility on crimped stent L1 to L5, which is the highest flexibility with von mises stress in the safety limit can be obtained based on a combination of link design parameters in the form of bending moment of 0.0074 N.mm with a thickness of 100 μm L3, and 0,0087 N.mm with a thickness of 106 μm L5. While at the expanded stent L1 to L5, the optimal link design parameter value for obtaining the best flexibility with von mises stress within the safety limit is a bending moment of 0.0075 N.mm with a thickness of 63.78 μm L3, 0.0067 N.mm with a thickness of 70 μm L5.

The global motion affecting electron transfer in Plasmodium falciparum type II NADH dehydrogenases: a novel non-competitive mechanism for quinoline ketone derivative inhibitors

The association of RYL-552 results in the weakening of intramolecular hydrogen bonds and large allosterism of NDH2. And there was a significant positive correlation between the angular change and the distance change.

Factors for the acquisition of 10° angular change at the lumbar spine through posterior column osteotomy in adult spinal deformity surgery

OBJECTIVEPosterior column osteotomy (PCO) has been known to provide an angular change (AC) of approximately 10° in sagittal plane deformity. However, whether PCO can actually obtain an AC of ≥ 10° depending on the particular level in the lumbar spine and which factors can effect a gain of ≥ 10° AC after PCO remain to be elucidated. The aim of this study was to identify the factors that effect a gain of ≥ 10° AC through PCO by comparing radiographic measurements between an AC group and a control group before and after adult spinal deformity (ASD) surgery.METHODSForty consecutive patients who underwent multilevel PCOs for ASD at a single institution between 2012 and 2016 were included in this study. PCO was performed in 142 disc space levels in the lumbar spine. The authors defined the disc space level that obtained ≥ 10° AC in the sagittal plane by PCO as the AC group and the remaining patients as controls. The modified Pfirrmann grade, surgical level, implementation of the transforaminal lumbar interbody fusion (TLIF), and radiographic measurements were compared between the groups.RESULTSThere were 67 levels in the AC group and 75 in the control group. Multivariate analysis identified the surgical level at L4–5 (OR 3.802, 95% CI 1.127–12.827, p = 0.031), performing TLIF with PCO (OR 3.303, 95% CI 1.258–8.674, p = 0.015), and a preoperative kyphotic disc space angle (OR 1.397, 95% CI 1.231–1.585, p < 0.001) as the factors that significantly effected ≥ 10° AC in the sagittal plane after PCO.CONCLUSIONSIn ASD surgery, PCO cannot always achieve ≥ 10° AC in the sagittal plane. The factors that effected ≥ 10° AC in PCO for ASD were surgical level at L4–5, performing TLIF with PCO, and the preoperative kyphotic disc space angle.