Optimal Alignment Research Articles

Arthroscopic Tibio-talar Calcaneal Nailing for Complex Distal Third and Intra-Articular Tibia Fractures

Distal tibia fractures are complex injuries with a high complication rate and unclear guidelines regarding operative timing for reduction and fixation. A tibial plafond fracture, or pilon fracture, is a fracture of the distal end of the tibia, often associated with complex comminuted fragments and surrounding soft-tissue injury compromise. Appropriate management of distal tibial and pilon fractures remains a challenge and existing research proves current surgical approaches have poor clinical outcomes. We propose that primary hindfoot arthrodesis using a tibio-talar calcaneal nail may be used as a successful method for treating complex distal tibial and pilon fractures, notably in those with coexisting medical comorbidities (diabetes, neuropathy, dementia, and compromised soft-tissue). The overall perioperative complication rate in this high-risk cohort may be reduced given a lesser invasive method for fixation. We hypothesize that primary hindfoot arthrodesis using an arthroscopic preparation and tibio-talar calcaneal nail for periarticular ankle trauma is a safe and effective surgical approach with optimal fracture alignment and stability. Level of Evidence: Level V.

Quantification of systematic errors in the electron density and temperature measured with Thomson scattering at W7-X

The electron density and temperature profiles measured with Thomson scattering at the stellarator Wendelstein 7-X show features which seem to be unphysical, but so far could not be associated with any source of error considered in the data processing.A detailed Bayesian analysis reveals that errors in the spectral calibration cannot explain the features observed in the profiles.Rather, it seems that small fluctuations in the laser position are sufficient to affect the profile substantially.The impact of these fluctuations depends on the laser position itself, which, in turn, provides a method to find the optimum laser alignment in the future.

Effect of the level of alveolar atrophy on implant placement accuracy in guided surgery for full-arch restorations supported by four implants: an in vitro study

BackgroundA fixed screw-retained full-arch restoration supported by four implants is a popular treatment option for edentulous arches. Optimal alignment of implants is quite challenging in extremely atrophied edentulous cases, and a small amount of deviation is expected during guided surgery. This study aimed to compare implant accuracy among edentulous jaws with various levels of atrophy.MethodsFive separate copies of each Cawood and Howell model (III–V) were produced for the maxilla and mandible. A total of 120 implants (30 models). The implant accuracy was assessed based on angular deviations at the base (angle, 3D offset, distal, vestibular, and apical) and tip (3D offset, distal, vestibular, and apical).ResultsThe atrophy level of the jaws had a statistically significant effect on deviation; implants showed greater deviation from the planned location as the atrophy level increased.ConclusionGiven that implant deviation increased with the degree of atrophy, a greater safety margin from important anatomical structures is recommended when planning implant location for guided surgery in Cawood and Howell V cases.

Multi-perspective conformance checking of uncertain process traces: An SMT-based approach

Conformance checking, one of the central tasks in process mining, compares the expected behavior described by a reference process model to the actual behavior recorded in an event log, with the goal of detecting deviations. Traditionally, it is assumed that the log provides a faithful and complete digital footprint of reality. However, assuming perfect logs is often unrealistic: real-life logs typically suffer from data quality issues, exposing uncertainty in their events, timestamps, and data attributes. We attack this problem by introducing a comprehensive framework for multi-perspective conformance checking dealing with uncertainty along three perspectives: control-flow, time, and data. From the modeling point of view, we consider process models formalized as Petri nets operating over data variables, and event logs presenting uncertainty at the event- and attribute-level. We cast conformance checking as an alignment problem, extending the traditional notions of alignment and cost function to deal with uncertainty along the three aforementioned perspectives. From the operational point of view, we show how (optimal) alignments can be computed through well-established automated reasoning techniques from Satisfiability Modulo Theories (SMT). Specifically, we show how previous results on data-aware SMT-based conformance checking can be lifted to this more sophisticated setting, obtaining a flexible framework that can seamlessly handle different variants of the problem. We formally prove correctness of our approach and implement it in the conformance checker cocomot. Finally, we perform a thorough experimental evaluation on synthetic and real-life logs, demonstrating the overall promising performance of our framework.

Revisiting Schistosoma mansoni Micro-Exon Gene (MEG) Protein Family: A Tour into Conserved Motifs and Annotation.

Genome sequencing of the human parasite Schistosoma mansoni revealed an interesting gene superfamily, called micro-exon gene (meg), that encodes secreted MEG proteins. The genes are composed of short exons (3-81 base pairs) regularly interspersed with long introns (up to 5 kbp). This article recollects 35 S. mansoni specific meg genes that are distributed over 7 autosomes and one pair of sex chromosomes and that code for at least 87 verified MEG proteins. We used various bioinformatics tools to produce an optimal alignment and propose a phylogenetic analysis. This work highlighted intriguing conserved patterns/motifs in the sequences of the highly variable MEG proteins. Based on the analyses, we were able to classify the verified MEG proteins into two subfamilies and to hypothesize their duplication and colonization of all the chromosomes. Together with motif identification, we also proposed to revisit MEGs' common names and annotation in order to avoid duplication, to help the reproducibility of research results and to avoid possible misunderstandings.

P102. Quantifying the impact of spinal shape: incorporating Roussouly criteria into novel alignment schemata increases probability of optimal radiographic alignment in adult spinal deformity surgery

P102. Quantifying the impact of spinal shape: incorporating Roussouly criteria into novel alignment schemata increases probability of optimal radiographic alignment in adult spinal deformity surgery

P97. Predicting good outcomes after adult spinal deformity surgery: analysis of preoperative symptoms with optimal radiographic alignment and patient outcomes

P97. Predicting good outcomes after adult spinal deformity surgery: analysis of preoperative symptoms with optimal radiographic alignment and patient outcomes

137. Achievement and maintenance of optimal alignment following adult spinal deformity corrective surgery: a 5-year outcome analysis

137. Achievement and maintenance of optimal alignment following adult spinal deformity corrective surgery: a 5-year outcome analysis

High contrast ratio and fast response ferroelectric liquid crystal displays based on alignment optimization

There are a series of polyimide material synthesized and studied with different dianhydride and diamine structures. By exploring the structural variations of these materials and their surface energy characteristics, we successfully obtained ferroelectric liquid crystal devices exhibiting exceptional optical and electrical properties. Notably, our findings highlight that a specific polyimide material comprised of dianhydride with a benzene ring structure and diamine with a long-chain amino structure demonstrates remarkable achievements, including a maximum contrast of 872 and a rapid response speed of less than 0.1 ms. These results establish the superiority of this particular polyimide material over its commercially available counterparts. Additionally, the optical characteristics of various polyimide materials were examined by establishing a correlation between these properties and the surface energy of the materials. This research presents a novel approach to developing alignment materials suitable for ferroelectric liquid crystal applications. The implications of our findings are of great significance in driving advancements in field-sequential-color display devices with high pixels per inch in the ferroelectric liquid crystal field.

Dynamic time warping to quantify age distortion in firn cores impacted by melt processes

Abstract As warming intensifies across the Greenland ice sheet, an increasing number of shallow coring and radar studies are targeting the melt-impacted firn column to investigate meltwater processes. Highly inhomogeneous infiltration and refreezing, however, redistributes mass, distorting age–depth relationships and confounding comparisons between different cores. Here, we utilize a dynamic time warping algorithm for time series alignment to investigate and quantify the heterogeneous impact of melt processes on nine closely spaced (within 50 m) firn core-density profiles. The 10 m cores were collected relatively high in Greenland's percolation zone, where melt alteration is minimal compared to lower elevation. Our analysis demonstrates the effectiveness of dynamic time warping as a tool for assessing heterogeneity between ice core records. We find that the optimal alignment of density profiles in the nine cores requires vertical stretching and compression of individual profiles, ranging from, on average, <1 to ~16% of the core lengths. We identified four depth zones of mass redistribution that appear to coincide with observed ice layers. Further, ~75% of density measurements from each core do not align with an age model-derived density profile that assumes no mass redistribution of meltwater, indicating the pervasive impact of melt processes.

A scalable parallel algorithm for global sequence alignment with customizable scoring scheme

SummarySequence alignment is a critical computational problem in various domains, including genomics, proteomics, and natural language processing. The Needleman‐Wunsch (NW) algorithm is a classical dynamic programming approach for finding the optimal global alignment between two sequences. However, its quadratic time and space complexity make it impractical for aligning large‐scale sequences, which are increasingly common in modern applications. In this article, we propose a parallel variation of the NW algorithm that enables scalable global sequence alignment with customizable scoring schemes. Our approach re‐formulates the dependencies in the NW algorithm to enable parallel execution, thereby leveraging the computational power of modern parallel architectures, such as graphics processing unit (GPU). Furthermore, our algorithm supports arbitrary linear scoring schemes, which allows us to use domain‐specific knowledge to improve alignment accuracy. We establish the correctness of our algorithm and evaluate its performance using real DNA and user trajectory sequences on GPUs. Our parallel algorithm has shown impressive results in our experiments, with a peak performance of 27.99 GCUPS (giga cell updates per second) and a maximum speedup of 48.18 times compared to the traditional sequential implementation. Additionally, our algorithm demonstrates remarkable scalability, enabling the alignment of sequences of any length while ensuring balanced work distribution and optimal utilization of resources. Our primary objective is to harness the computational capabilities of a single GPU and fully utilize the processing power of multi‐core CPUs.

A RANDOMIZED CONTROLLED TRIAL OF KINEMATICALLY AND MECHANICALLY ALIGNED TOTAL KNEE ARTHROPLASTY: 12-YEAR FOLLOW-UP

AbstractIntroductionThe optimal alignment technique for total knee replacement (TKR) remains controversial. We previously reported six-month and two-year results of a randomized controlled trial comparing kinematically (KA) versus mechanically (MA) aligned TKR. In the present study, we report 12-year results from this trial.MethodsThe original cohort included 88 TKRs (44 KA using Shape Match patient-specific guides and 44 MA using conventional instrumentation), performed from 2008 to 2009. After IRB approval, the health record of the original 88 patients were queried. Revisions, re-operations, and complications were recorded. The non-deceased patients were contacted via phone. Reoperation and complications were documented via the patient's history. Further, a battery of patient-reported outcome measures (including patient satisfaction, WOMAC, Oxford, KOOS Jr, Forgotten Joint Score, and M-SANE) were obtained.ResultsOf the original 88 patients in the study, 15 patients had a least one reoperation (17%). Patella problems were the most common cause of reoperation accounting for 5/8 reoperations in the KA group versus 3/7 in the MA group. There was no statistically significant difference between the two alignment methods in terms of major and minor complications or reoperations. At the 12-year follow-up, 26 patients died leaving 62 patients for follow-up. Of these, 48 patients (77%) were successfully contacted. The kinematically aligned total knees self-reported better satisfaction (96% versus 82%), but no difference in other patient-reported outcome measures compared to mechanically aligned TKRs.ConclusionKA TKR demonstrates excellent mid to long-term results compared to MA TKR with similar reoperations, complications, and patient-reported outcome measures.

Optimization of Longitudinal Alignment of an 4f System in a Compact Vectorial Optical-Field Generator Based on a High-Resolution Liquid Crystal Spatial Light Modulator

Vectorial optical fields have garnered significant attention due to their potential applications in areas such as optical nano-fabrication, optical micromachining, quantum information processing, optical imaging, and so on. Traditional compact vectorial optical generators with amplitude modulation perform poorly in terms of diffraction effect reduction. To tackle this problem, the refractive 4f system in amplitude modulation is longitudinally aligned using an optimization approach presented in this research. The phase images used for longitudinal alignment are loaded into the liquid crystal spatial light modulator (SLM), and the distance between the lens and the mirror in the reflective 4f system is adjusted for longitudinal alignment by compensating for the neglected phase in the integrated module for the compact vectorial optical-field generator. The spot images collected by the CCD are processed using the improved eight-direction Sobel operator and Roberts function, and the longitudinal alignment in the reflective 4f system is determined by the sharpness of the image. The sharpness of the edges of the lines and the overall image are both enhanced after optimization compared to before optimization. The results demonstrate that the proposed method can effectively reduce the longitudinal alignment error of the reflective 4f system in the amplitude modulation of the compact vectorial optical-field generator, lessen the diffraction effect, and improve the performance of the system.

Measurement invariance testing using confirmatory factor analysis and alignment optimization: A tutorial for transparent analysis planning and reporting.

Measurement invariance-the notion that the measurement properties of a scale are equal across groups, contexts, or time-is an important assumption underlying much of psychology research. The traditional approach for evaluating measurement invariance is to fit a series of nested measurement models using multiple-group confirmatory factor analyses. However, traditional approaches are strict, vary across the field in implementation, and present multiplicity challenges, even in the simplest case of two groups under study. The alignment method was recently proposed as an alternative approach. This method is more automated, requires fewer decisions from researchers, and accommodates two or more groups. However, it has different assumptions, estimation techniques, and limitations from traditional approaches. To address the lack of accessible resources that explain the methodological differences and complexities between the two approaches, we introduce and illustrate both, comparing them side by side. First, we overview the concepts, assumptions, advantages, and limitations of each approach. Based on this overview, we propose a list of four key considerations to help researchers decide which approach to choose and how to document their analytical decisions in a preregistration or analysis plan. We then demonstrate our key considerations on an illustrative research question using an open dataset and provide an example of a completed preregistration. Our illustrative example is accompanied by an annotated analysis report that shows readers, step-by-step, how to conduct measurement invariance tests using R and Mplus. Finally, we provide recommendations for how to decide between and use each approach and next steps for methodological research. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Efficacy of Varying Surgical Approaches on Achieving Optimal Alignment in Adult Spinal Deformity Surgery.

The Roussouly, SRS-Schwab, and GAP classifications define alignment by spinal shape and deformity severity. The efficacy of different surgical approaches and techniques to successfully achieve these goals is not well understood. Identify the impact of surgical approach and/or technique on meeting complex realignment goals in adult spinal deformity(ASD) corrective-surgery. Retrospective. Included: ASD patients fused to pelvis with two-year(2Y) data. Patients were categorized by: 1)Roussouly: matching current and theoretical spinal shapes; 2)improving in SRS-Schwab modifiers(0, +, ++); 3)improving GAP Proportionality by 2Y. ANCOVA and multivariable logistic regression analyses controlling for age, levels fused, baseline deformity, and three-column osteotomy usage compared the effect of different surgical approaches, interbody and osteotomy use on meeting realignment goals. 693 ASD patients were included. By surgical approach, 65.7% were posterior-only and 34.3% underwent anterior-posterior(AP) approach with 76% receiving an osteotomy(21.8% 3CO). By 2Y, 34% matched Roussouly, 58% improved in GAP, 45% in SRS-Schwab PT, 62% SVA, and 70% PI-LL. Combined approaches were most effective for improvement in PT(OR: 1.7,[1.1-2.5]) and GAP(OR: 2.2,[1.5-3.2]). Specifically, ALIFs below L3 demonstrated higher rates of improvement versus TLIFs in Roussouly(OR: 1.7, [1.1-2.5]) and GAP(OR: 1.9, [1.3-2.7]). Patients undergoing PSO at L3 or L4 were more likely to improve in PT(OR: 2.0,[1.0-5.2]) and PI-LL(OR: 3.8[1.4-9.8]). Clinically, patients undergoing combined approach demonstrated higher rates of meeting SCB in ODI by 2Y while minimizing rates of PJF, most often with an ALIF at L5-S1(ODI-SCB: OR: 1.4,[1.1-2.0];PJF: OR: 0.4,[0.2-0.8]). Among patients undergoing ASD realignment, optimal lumbar shape and proportion can be achieved more often with a combined approach. While TLIFs incorporating a three-column osteotomy at L3 and L4 can restore lordosis and normalize pelvic compensation, ALIFs at L5-S1 were most likely to achieve complex realignment goals with an added clinical benefit and mitigation of junctional failure.

Mountain railway alignment optimization based on landform recognition and presetting of dominating structures

AbstractMountain railway alignment optimization has always been a challenge for designers and researchers in this field. It is extremely difficult for existing methods that optimize alignments before major structures to generate a better alignment than the best one provided by human designers when the terrain is drastically undulating between the start and endpoints. To fill this gap, a “structures before alignments” design process is proposed in this paper. Primarily, a landform recognition method is devised for recognizing dominating landforms. Then, a bi‐level alignment optimization model is proposed, with the upper level dedicated to characterizing dominating structures and the lower level focusing on optimizing the entire alignments. To solve this bi‐level model, a three‐stage optimization method is designed. At the first stage, a scanning process and screening operators are devised for generating all the possible locations of dominating structures. At the second stage, a hierarchical multi‐criteria decision‐making procedure is applied for selecting the optimized dominating structure layouts. At the third stage, alignments are optimized based on the determined structure layouts using a bi‐objective optimization method, which minimizes construction cost and geo‐hazard risk simultaneously. The proposed model and solution method are applied to two real‐world cases whose results verify their capabilities in producing alignment alternatives with better combinations of construction cost and geo‐hazard risk than manually designed alternatives.

Clinical and structural outcomes of neocommissural alignment in transaxillary and transcarotid transcatheter aortic valve implantation with a self-expandable transcatheter heart valve

ObjectivesThis study analyzes neocommissural alignment and the clinical and hemodynamic outcomes after transaxillary and transcarotid implantation of the Acurate neo2 transcatheter heart valve. MethodsWe performed a retrospective, single-center analysis of early outcomes after transaxillary and transcarotid implantation of the Acurate neo2 transcatheter heart valve. Primary outcomes were neocommisural alignment, in-hospital mortality, and valve hemodynamic performance. Commissural alignment between native and transcatheter heart valves was assessed by transesophageal echocardiogram before and after the procedure. ResultsBetween October 2021 and November 2022, 40 consecutive patients were treated with the Acurate neo2 through a transaxillary or transcarotid approach. Access was achieved via the left subclavian artery in 30 cases and the left common carotid artery in 10 cases, with a mean vessel diameter of 6.7 mm. Implants most commonly used were size M (37.5%), L (35%), and S (27.5%). On the basis of transesophageal echocardiogram analysis, there was no significant difference in mean commissural orientation between native (mean, 65.1°; SD, 41.3°) and neocommissures (mean, 64°; SD, 44.1°) (P = .661). Mean commissural orientation did not significantly differ between native and neocommissures (P = .661). Optimal alignment or mild commissural misalignment was achieved in 99.5% of cases. There were no cases of severe commissural misalignment. Postprocedural mean values for peak and mean gradients were 12.7 mm Hg and 5.2 mm Hg, respectively. There were 2 cases of moderate paravalvular leak and 4 cases of mild paravalvular leak. ConclusionsThis patient-specific technique for transaxillary and transcarotid insertion of the Acurate neo2 delivery system prevents implantations with more than mild commissural misalignment and with a high device success rate.

Query-by-Example Spoken Term Detection for Zero-Resource Languages Using Heuristic Search

Query-by-Example spoken content retrieval is a demanding and challenging task when a large volume of spoken content is piled up in the repositories without annotation. In the absence of annotation, spoken content retrieval is achieved by capturing the similarities between the query and spoken terms from the acoustic feature representation itself. Dynamic Time Warping (DTW) centric techniques identify the optimal alignment between the acoustic feature representations and capture the similarities between query and spoken terms. Despite feasibility, the DTW-centric techniques produce a lot of false alarms due to the variabilities that exist in natural speech and degrade the performance. In the proposed approach, the variability challenges are addressed in two stages. At first, the speaker-independent acoustic feature representation was obtained from the deep convolutional neural networks that reduce the speaker variabilities. In the second stage, the similarities between the query and spoken term were captured using the heuristic search method. The proposed approach was compared with other state-of-the-art methods using Microsoft Low-Resource Language speech corpus. A 3% improvement and 32% reduction in the hit and false alarm ratio were achieved across languages.

A multi-road quasi network flow model for the vertical alignment optimization of a road network

ABSTRACT Minimizing earthwork costs is crucial in the optimization of vertical alignment. In this article, the previous quasi network flow model for the vertical alignment optimization of a single road is extended to a multi-road network. A ‘one-at-a-time’ method is first examined to solve the optimization problem and it is noted that this method is effectively what is currently used in practice. Two academic test problems are used to demonstrate that this method is not optimal. This leads to the development of three novel methods to solve the optimization problem: no-flow, with-flow and divide-and-conquer. It is noted that the with-flow method guarantees global optimality. All methods are compared on two real-world case studies. On small road networks, the with-flow method decreases costs by 7.4%, and achieves a 20 times speedup over the one-at-a-time method. On long road networks, the divide-and-conquer method is faster than all other methods without any notable cost difference. However, the divide-and-conquer method is an heuristic and cannot guarantee that it returns a global minimum.

The Linear Coronal Knee Offset (LCKO)-Preliminary Study of New Method of Measuring Knee Varus/Valgus Malalignment.

Introduction Considerable attention is focused on preoperative templating of radiological images in patients undergoing total knee arthroplasty to obtain optimal alignment and outcome. Several radiological measurements have been described. Purpose In this study, we illustrate a new linear measurement: The linear coronal knee offset (LCKO) that can be used to analyze the coronal configuration on long leg alignment radiographs commonly undertaken during preoperative templating. Methods A retrospective search was performed of our Picture Archiving and Communication System and Radiology Information System to identify 100 lower limbs anteroposterior, weight bearing, long leg alignment view radiographs of patients referred to knee clinics over 1 year with knee pain. Demographic details, clinical indication, standard radiological measurement of the anatomical tibiofemoral angle, and the LCKO were measured and data were analyzed using Student's t -test. In addition, intraclass correlation coefficient was used to analyze for intraclass reliability. Results The average age of patients was 36.3 years (range: 12-80 years) with a male predominance. The LCKO was statistically significant between the three cohorts of patients. The mean LCKO in normal cohorts was 0.24 cm, varus was -0.6 cm, and valgus was 1.72cm. There was good inter and interobserver reliability (Kappa of 0.8 and 0.8, respectively). Conclusion The novel LCKO measurement provides a simpler method in assessing coronal lower limb malalignment and can easily identify a normal, varus, or valgus knee deformity.