Optimal Alignment Research Articles

Simplified Graph Contrastive Learning for Recommendation with Direct Optimization of Alignment and Uniformity

Simplified Graph Contrastive Learning for Recommendation with Direct Optimization of Alignment and Uniformity

Navigated versus conventionally instrumented total knee arthroplasty techniques: No difference in functional alignment or balance.

Much debate exists about the superiority of navigated versus conventional instrumentation for achieving optimal balance and alignment during total knee arthroplasty (TKA). Recent registry data indicate no long-term survivorship benefit for TKAs performed using technology assistance, despite the added resource and financial costs. However, outcome comparisons are confounded by varying surgeon techniques and targets for ideal balance and alignment. This study aimed to investigate alignment or balance outcome differences between navigated and conventionally instrumented TKAs performed using an identical operative sequence and alignment strategy. Fifty navigated and 50 conventionally instrumented primary TKAs, using an identical inverse kinematic alignment strategy, were included. Navigation equipment was used intraoperatively to 'post-cut' record the conventionally instrumented TKAs. Intraoperative balance, range, and alignment; and post-operative radiographic accuracy for restoration of constitutional alignment were compared. Forty-nine navigated and 49 conventionally instrumented TKAs were compared (n = 2 excluded due to inadequate radiographs). No preoperative demographic or deformity severity differences existed. No intraoperative balance, range or alignment difference existed. Neither technique was more accurate for restoration of constitutional alignment. Whilst large registry data may be confounded by uncaptured variables such as surgeon balancing techniques or surgeon alignment strategy preferences, this study found no alignment or balance differences between navigated versus conventionally instrumented TKA techniques for a surgeon and technique-controlled study. Although the increased resources necessary for technology assistance are not justified by this study, further studies may identify significance using larger samples or comparison of alternative outcomes. Level II.

CPPF++: Uncertainty-Aware Sim2Real Object Pose Estimation by Vote Aggregation.

Object pose estimation constitutes a critical area within the domain of 3D vision. While contemporary state-of-the-art methods that leverage real-world pose annotations have demonstrated commendable performance, the procurement of such real training data incurs substantial costs. This paper focuses on a specific setting wherein only 3D CAD models are utilized as a priori knowledge, devoid of any background or clutter information. We introduce a novel method, CPPF++, designed for sim-to-real category-level pose estimation. This method builds upon the foundational point-pair voting scheme of CPPF, reformulating it through a probabilistic view. To address the challenge posed by vote collision, we propose a novel approach that involves modeling the voting uncertainty by estimating the probabilistic distribution of each point pair within the canonical space. Furthermore, we augment the contextual information provided by each voting unit through the introduction of N-point tuples. To enhance the robustness and accuracy of the model, we incorporate several innovative modules, including noisy pair filtering, online alignment optimization, and a tuple feature ensemble. Alongside these methodological advancements, we introduce a new category-level pose estimation dataset, named DiversePose 300. Empirical evidence demonstrates that our method significantly surpasses previous sim-to-real approaches and achieves comparable or superior performance on novel datasets.

Integrating Energy-Efficient Train Control in railway Vertical Alignment Optimization: A novel Mixed-Integer Linear Programming approach

Incorporating train control into the railway design process enables a practical and comprehensive evaluation of the lifecycle utility of a track profile. This paper proposes a novel integrated approach, termed EETC-VAO, which combines railway track Vertical Alignment Optimization (VAO) and Energy-Efficient Train Control (EETC). Initially formulated as a Mixed-Integer Nonlinear Programming (MINLP) problem, EETC-VAO aims to meet various geometric constraints and simultaneously minimize construction costs, traction energy consumption, and section running times in both directions. The model is subsequently reformulated into an equivalent Mixed-Integer Linear Programming (MILP) model using linearization methods and is further enhanced with valid inequalities, logic cuts, and a warm start algorithm with random velocity generation. The model has been extensively tested across a variety of case studies and train types, from synthetic small-scale scenarios to challenging real-world cases spanning from 3 to 71.2 km. Our findings demonstrate that operational costs can be significantly reduced with only marginal increases in construction costs. The integrated approach achieves reductions in total lifecycle costs of up to 40%, revealing a critical trade-off between construction and operational expenses. Notably, our results also indicate that lower construction costs do not inherently conflict with reduced operational costs, emphasizing the critical importance of integrating the train control scheme into the VAO problem.

Achieving Better Clinical Outcomes After Total Knee Arthroplasty in Knees with Valgus Deformity: The Role of Alignment Strategies.

Personalized alignment in total knee arthroplasty (TKA) has demonstrated good functional outcomes for knees with varus alignment. However, limited research has explicitly addressed optimal alignment strategies for valgus knees. The aims of the current study were to assess the impact of the postoperative knee alignment and of the degree of correction of knee alignment on functional outcomes and satisfaction in a population with preoperative valgus and to evaluate the complication and revision rates based on postoperative alignment. This retrospective study included primary posterior-stabilized TKA with a preoperative hip-knee-ankle (HKA) angle of ≥180°, with a minimum follow-up of 32 months. There were 460 knees included, divided into 3 groups: (1) preoperative neutral alignment (180° to 183°) (n = 162), (2) preoperative mild valgus (184° to 190°) (n = 204), and (3) preoperative severe valgus (>190°) (n = 94). A standardized surgical technique was employed with a goal of achieving neutral postoperative alignment. Data on radiographs, Knee Society Scores (KSS), range of motion, satisfaction, complications, and revisions were collected at the last follow-up. The mean follow-up was 74.3 ± 12.4 months. In the preoperative mild valgus group, 10.8% of patients had postoperative varus, 81.4% had postoperative neutral alignment, and 7.8% had postoperative valgus. In the preoperative severe valgus group, 4.3% had postoperative varus, 83.0% had postoperative neutral alignment, and 12.8% had postoperative valgus. In the preoperative mild valgus group, patients with postoperative neutral alignment had significantly higher satisfaction (p = 0.0004) and KSS function score (p = 0.031) than patients with postoperative valgus alignment. In the preoperative severe valgus group, patients with postoperative valgus alignment had significantly higher satisfaction (p = 0.035) and greater improvement of the KSS knee score (p = 0.014) than patients with postoperative neutral alignment. Functional outcomes were not impacted by the degree of HKA angle correction. There were significantly fewer complications (p = 0.022) and revisions (p = 0.007) in the preoperative mild valgus group when patients had a postoperative neutral alignment compared with a postoperative valgus alignment. For preoperative mild valgus, correction to neutral alignment achieved better outcomes and fewer complications than leaving residual valgus. For preoperative severe valgus, retaining residual valgus postoperatively ensured satisfactory functional outcomes without increased complications. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Strategies for the alignment of electronic states in quantum-dot tunnel-injection lasers

In quantum-dot tunnel-injection lasers, the excited charge carriers are efficiently captured from the bulk states via an injector quantum well and then transferred into the quantum dots via a tunnel barrier. The alignment of the electronic levels is crucial for the high efficiency of these processes and especially for the fast modulation dynamics of these lasers. In particular, the quantum mechanical nature of the tunneling process must be taken into account in the transition from two-dimensional quantum well states to zero-dimensional quantum-dot states. This results in hybrid states, from which the scattering into the quantum-dot ground states takes place. We combine electronic state calculations of the tunnel-injection structures with many-body calculations of the scattering processes and insert this into a complete laser simulator. This allows us to study the influence of the structural design and the resulting electronic states as well as limitations due to inhomogeneous quantum-dot distributions. We find that the optimal electronic state alignment deviates from a simple picture in which the quantum-dot ground state energies are one LO-phonon energy below the injector quantum well ground state.

Engineering Biomimetic Microvascular Capillary Networks in Hydrogel Fibrous Scaffolds via Microfluidics-Assisted Co-Axial Wet-Spinning.

The microvascular bed plays a crucial role in establishing nutrient exchange and waste removal, as well as maintaining tissue metabolic activity in the human body. However, achieving microvascularization of engineered 3D tissue constructs is still an unsolved challenge. In this work, we developed biomimetic cell-laden hydrogel microfibers recapitulating oriented microvascular capillary-like networks by using a 3D bioprinting technique combined with microfluidics-assisted coaxial wet-spinning. Highly packed and aligned bundles embedding a coculture of human bone marrow-derived mesenchymal stem cells (MSCs) and human umbilical vein endothelial cells (HUVECs) were produced by simultaneously extruding two different bioinks. To this aim, core-shell fibers were wet-spun in a coagulation bath to collect the scaffolds later on a rotary drum. Initially, the versatility of the proposed system was assessed for the extrusion of multimaterial core-shell hydrogel fibers. Subsequently, the platform was validated for the in vitro biofabrication of samples promoting optimal cell alignment along the fiber axis. After 3 weeks of culture, such fiber configuration resulted in the development of an oriented capillary-like network within the fibrin-based core and in the endothelial-specific CD31 marker expression upon MSC/HUVEC maturation. Synergistically, the vertical arrangement of the coaxial nozzle coupled with the rotation of the fiber collector facilitated the rapid creation of tightly packed bundles characterized by a dense, oriented, and extensively branched capillary network. Notably, such findings suggest that the proposed biofabrication strategy can be used for the microvascularization of tissue-specific 3D constructs.

3DGSR: Implicit Surface Reconstruction with 3D Gaussian Splatting

In this paper, we present an implicit surface reconstruction method with 3D Gaussian Splatting (3DGS), namely 3DGSR, that allows for accurate 3D reconstruction with intricate details while inheriting the high efficiency and rendering quality of 3DGS. The key insight is to incorporate an implicit signed distance field (SDF) within 3D Gaussians for surface modeling, and to enable the alignment and joint optimization of both SDF and 3D Gaussians. To achieve this, we design coupling strategies that align and associate the SDF with 3D Gaussians, allowing for unified optimization and enforcing surface constraints on the 3D Gaussians. With alignment, optimizing the 3D Gaussians provides supervisory signals for SDF learning, enabling the reconstruction of intricate details. However, this only offers sparse supervisory signals to the SDF at locations occupied by Gaussians, which is insufficient for learning a continuous SDF. Then, to address this limitation, we incorporate volumetric rendering and align the rendered geometric attributes (depth, normal) with that derived from 3DGS. In sum, these two designs allow SDF and 3DGS to be aligned, jointly optimized, and mutually boosted. Our extensive experimental results demonstrate that our 3DGSR enables high-quality 3D surface reconstruction while preserving the efficiency and rendering quality of 3DGS. Besides, our method competes favorably with leading surface reconstruction techniques while offering a more efficient learning process and much better rendering qualities.

Computational screening of 2D ternary penta-materials with auxetic properties and efficient photocatalytic CO2 reduction

Due to unique structural and electronic properties, pentagon-based two-dimensional (2D) materials have captured significant interest in recent years. However, previous studies on these materials have primarily focused on unary and binary systems, with less exploration of ternary pentagonal structures. Herein, we conducted first-principles calculations to evaluate the stability of 122 ternary pentagonal monolayers composed of metals, nitrogen, and chalcogen. We identify six highly stable candidates, including AuNS, CuNTe, GaNS, InNS, SbNS, and SbNSe that meet the criteria for thermodynamic, mechanical, and dynamic stability. Mechanical property analysis reveals that five of these monolayers demonstrate auxetic behavior. Electronic structure calculations show that all candidates are semiconductors with band gaps ranging from 0.12 to 3.42 eV. Specifically, the SbNS and SbNSe monolayers are indirect semiconductors with band gaps of 2.25 and 2.27 eV, respectively. These materials exhibit strong visible light absorption, and potentially serve as exceptional photocatalysts for the reduction of CO2 to CH4 due to the optimal band alignment. The free energy change in the rate-limiting step is even lower than those found in g-C3N4 and MoS2-based systems. Our findings highlight new pentagon-based 2D materials with remarkable electronic, mechanical, and optical properties, making them promising candidates for applications in mechanics and energy conversion.

REFERENCE AREAS SELECTION AFFECTS REGISTRATION OF AI-SEGMENTED MANDIBLES ACQUIRED WITH CBCT

Introduction Precise registration of sequential 3D datasets is crucial for accurate dimensional analysis. Utilizing the Local Best-Fit (LBF) algorithm and stable Registration Reference Areas (RRAs) facilitates the accurate alignment of 3D surface models. Currently, Cone-beam Computed Tomography (CBCT) and Deep Learning (DL) algorithms are at the forefront for segmenting CBCT scans to monitor morphological changes in the residual alveolar ridge. This study compares the effectiveness of different RRAs in registration sequential 3D surface models of partially edentulous mandibles. Methods DL-assisted software segmented two sequential CBCTs (T0 and T1) from 10 patients, producing sequential 3D mandibular models. These models were aligned using three distinct RRAs: (i) WHOLE, encompassing the entire surface model; (ii) MND_BODY, covering the mandibular body while excluding the unstable alveolar ridge; and (iii) SPIN_FOR, incorporating stable RRAs (mental foramina and mental spine). An innovative method assessed registration accuracy by generating centroids from cross-sectional outlines of the mandibular nerve canals at the anterior third (A), medial third (B), and posterior third (C) of the posterior edentulous areas. The distance between centroids at T0 and T1 quantified registration accuracy. Results The MND_BODY group exhibited superior accuracy, whereas the SPIN_FOR group showed the least, with accuracy decreasing from A to C, suggesting rotational misalignments. ConclusionsWhen selecting RRAs, both stability and spatial distribution must be taken into account. For optimal alignment, sequential 3D surface models should use RRAs that are both stable and widely distributed.

REDalign: accurate RNA structural alignment using residual encoder-decoder network

BackgroundRNA secondary structural alignment serves as a foundational procedure in identifying conserved structural motifs among RNA sequences, crucially advancing our understanding of novel RNAs via comparative genomic analysis. While various computational strategies for RNA structural alignment exist, they often come with high computational complexity. Specifically, when addressing a set of RNAs with unknown structures, the task of simultaneously predicting their consensus secondary structure and determining the optimal sequence alignment requires an overwhelming computational effort of O(L6)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$O(L^6)$$\\end{document} for each RNA pair. Such an extremely high computational complexity makes these methods impractical for large-scale analysis despite their accurate alignment capabilities.ResultsIn this paper, we introduce REDalign, an innovative approach based on deep learning for RNA secondary structural alignment. By utilizing a residual encoder-decoder network, REDalign can efficiently capture consensus structures and optimize structural alignments. In this learning model, the encoder network leverages a hierarchical pyramid to assimilate high-level structural features. Concurrently, the decoder network, enhanced with residual skip connections, integrates multi-level encoded features to learn detailed feature hierarchies with fewer parameter sets. REDalign significantly reduces computational complexity compared to Sankoff-style algorithms and effectively handles non-nested structures, including pseudoknots, which are challenging for traditional alignment methods. Extensive evaluations demonstrate that REDalign provides superior accuracy and substantial computational efficiency.ConclusionREDalign presents a significant advancement in RNA secondary structural alignment, balancing high alignment accuracy with lower computational demands. Its ability to handle complex RNA structures, including pseudoknots, makes it an effective tool for large-scale RNA analysis, with potential implications for accelerating discoveries in RNA research and comparative genomics.

Efficacy of R-N cusp-overlap view as a complementary approach for optimal neocommissural alignment with Navitor valve.

Efficacy of R-N cusp-overlap view as a complementary approach for optimal neocommissural alignment with Navitor valve.

Distal Femur Morphology in a Brazilian Population: Challenging the Universal Use of 3-Degrees of External Rotation

Objectives: To assess the external rotation angle between the transepicondylar axis (TEA) and the posterior condylar axis (PCA) in a Brazilian population, to determine whether the universal use of 3-degrees external rotation of the femoral component is appropriate during total knee arthroplasty (TKA) in this population. Methods: The TEA rotation relative to the PCA was measured in 167 magnetic resonance imaging (MRI) exams using four different methods for the PCA, based on posterior reference points: (A) cartilage references; (B) bony references; (C) lateral posterior reference and medial cartilage reference; and (D) lateral cartilage reference and medial bony reference. The measurements were statistically compared to the traditional 3-degrees external rotation used in TKA instrumentation. An analysis of variance was conducted to assess differences between the measurement methods. Results: Mean TEA external rotation for methods A, B, C, and D was 5.44º ± 2.39º, 4.94º ± 2.10º, 8.56º ± 2º, and 2.33º ± 2º, respectively. All measurement methods showed significant differences compared to the traditional 3-degrees external rotation (p<.0001). Significant differences were also found between all measurement methods (p<.0001), except between methods A and B (p=0.1614). Conclusion: Using cartilage or bony reference points for the PCA, the TEA in the Brazilian population is approximately 5-degrees externally rotated. The traditional 3-degrees femoral component rotation may be insufficient for this population, particularly in valgus knees. This highlights the importance of an individualized approach to achieve optimal component rotational alignment during TKA.

Telemedicine Compared to Office-Based Care of Patients With Cardiac Symptoms: Treatment and Outcomes

BackgroundAn increasing proportion of visits are now delivered via a virtual platform. Virtual visits are limited by the lack of important components of cardiovascular assessment such as physician examination and electrocardiogram. ObjectivesThe purpose of this study was to evaluate the quality of care delivered by virtual visits compared to office-based visits among adults who sought care for three common cardiac-related symptoms: dyspnea, dizziness, or palpitations. MethodsRetrospective cohort study of 992,526 outpatient visits between January 1, 2017, and December 31, 2021, within an integrated health system, including 356,159 visits for dyspnea, 412,913 for dizziness, and 223,454 for palpitations. We compared the differences in patient characteristics associated with telemedicine visits versus in-office visits, evaluated the referral rates for noninvasive cardiac testing, and examined the association between virtual visits and 30-day clinical outcomes. ResultsAmong 992,526 visits, 71.5% were office visits, 25.8% telephone visits, and 2.7% video visits. Median age was 59 (IQR: 43-72) years, and 63.1% were women. Patient characteristics associated with increased likelihood of virtual visits included younger age, female sex, being non-Hispanic Black, and being from lower-income households. No association was observed between visit types and 30-day cardiovascular hospitalization for patients with dizziness or palpitations. However, for patients with dyspnea, evaluation via virtual visits was associated with a higher risk of 30-day hospitalization for heart failure (aOR: 1.25; 95% CI: 1.16-1.36 for telephone visits; aOR: 1.45; 95% CI: 1.17-1.80 for video visits). Compared to office-based visits, patients with dyspnea were less likely to be referred for echocardiogram with telephone (aOR: 0.73; 95% CI: 0.72-0.75) or video visits (aOR: 0.92; 95% CI: 0.87-0.98). ConclusionsVirtual visits may be appropriate for some clinical concerns but not all. Optimal alignment of clinical conditions with appropriate care modalities is an important component of a successful telemedicine strategy.

Anterior Cruciate and Anterior Oblique Ligament Reconstruction Using Hamstrings and Peroneus Longus’ Anterior Half Grafts

Objective: To describe the surgical technique for anterior cruciate ligament (ACL) and anterior oblique ligament (AOL) reconstruction using hamstring tendons and the anterior half of the peroneus longus tendon. Methods: The surgical technique involves the following key steps: 1. Tendon Harvesting: The semitendinosus and gracilis (STG) tendons are harvested from the injured limb or the contralateral limb in cases of prior ACL reconstruction. Additionally, a 3 cm longitudinal incision is made in the posterolateral region of the fibula to harvest the anterior half of the peroneus longus (PL) tendon, ensuring the fibular nerve is not injured. The harvested tendons form a quintuple graft, with the STG folded four times and the PL used as a fifth component. 2. Graft Preparation: The STG graft is folded to create a quadruple graft, and the PL is integrated into this without folding, forming a quintuple graft proximally. The distal portion remains single, extending the PL length. 3. Tunnel Positioning for ACL: The reconstruction involves precise anatomic positioning of the femoral and tibial tunnels. The femoral tunnel is created in the Anatomical Functional Position, as described by Jorge et al., using an outside-in technique with the Acufex Pinpoint guide (Smith & Nephew). The tibial tunnel is positioned on the anteromedial surface of the tibia, ensuring optimal alignment with the femoral tunnel. 4. Femoral Tunnel for AOL: The femoral tunnel for the AOL is positioned at the medial epicondyle. Fluoroscopy is used to identify the medial epicondyle in the lateral view. A guidewire is passed through the anterior portion of the medial epicondyle, creating a tunnel under radiographic visualization to ensure correct anatomical placement of the AOL. 5. Graft Passage and Fixation: The graft is passed through the tibial and femoral tunnels using a No. 5.0 Ethibond suture. The quintuple graft occupies both tunnels, and the single PL portion remains outside the tibial tunnel until fixation. Femoral fixation is achieved with an interference screw (Biosure; Smith & Nephew). After pretensioning, tibial fixation is completed with the knee in full extension. The remaining PL is passed subcutaneously on the medial side and fixed in the AOL tunnel with the knee in neutral rotation and 45 degrees of flexion. This technique ensures optimal biomechanical restoration and stability in the anterolateral and anteromedial knee compartments. Results: This technique aims to improve knee stability by addressing anterolateral and anteromedial instability, which is critical in some instances of ACL injury. Using the anterior half of the peroneus longus tendon in conjunction with hamstring tendons provides a viable, biomechanically sound option for reconstruction. Conclusion: Combined ACL and AOL reconstruction using hamstring and peroneus longus tendons is a promising technique for improving knee stability in patients with ACL injuries, particularly those with anteromedial instability. This approach may be a valuable alternative to exclusive anterolateral reinforcement in select cases.

Knowledge graph-driven mountain railway alignment optimization integrating karst hazard assessment

Karst hazard is a considerable threat that should be considered in railway alignment design for mountainous regions with dense water systems. Nevertheless, alignment design principles in karst regions have not been systematically studied. Moreover, a quantitative karst hazard assessment model is currently lacking for automated alignment optimization. To solve the above problems, based on the analyses of karst inducing factors and hazard representation, the railway alignment design principles in karst regions are summarized through an event tree. A highly-coupled knowledge graph (called KaRAD-KG) modeling method is proposed. Then, a bi-objective alignment optimization model considering railway construction cost and karst hazard (mainly including hazard components of synclinal karst, anticlinal karst and karst depression) is constructed. To solve the optimization model, a knowledge-driven distance transform algorithm incorporating a karst hazard assessment method and a multicriteria tournament decision method is customized. Finally, the application in a real-world case indicates that the proposed method can generate an alignment which reduces construction cost by 3.39 % and karst hazard by 18.73 % compared to the best manually-designed alternative, which verifies the effectiveness of this method for assisting actual railway alignment design in a karst-dense mountainous region.

ROSHAMBO: Open-Source Molecular Alignment and 3D Similarity Scoring.

Efficient virtual screening techniques are critical in drug discovery for identifying potential drug candidates. We present an open-source package for molecular alignment and 3D similarity calculations optimized for large-scale virtual screening of small molecules. This work parallels widely used proprietary tools and offers an approach complementary to structure-based virtual screening. Our package employs the PAPER software for optimizing molecular alignments based on Gaussian volume overlaps. GPU acceleration is utilized to significantly reduce computational time and resource requirements. After obtaining the optimal alignments between the target and the query molecules, both shape and color (based on pharmacophore features) scores are computed to assess molecular similarity, with aligned molecules optionally being output in sdf format. The package was benchmarked using the DUDE-Z public data sets. Results demonstrated the package's near-state-of-the-art performance and robustness across multiple target classes, with speed that enables many routine ligand-based drug discovery workflows. As an open-source and freely available resource (github.com/molecularinformatics/roshambo) with both a convenient Python API and command line interface, our package also addresses the need for accessible and efficient virtual screening tools in drug discovery.

Pyrene‐Based Self‐Assembled Monolayer with Improved Surface Coverage and Energy Level Alignment for Perovskite Solar Cells

AbstractRecently, the efficiency of p‐i‐n perovskite solar cells drastically increased, a pivotal factor being the incorporation of self‐assembled monolayers (SAMs) as a hole‐transporting layer (HTL). SAMs offer many advantages over conventional HTLs, including minimal material requirements, low cost, and facile processing. Current research is mainly focused on the development of carbazole‐derived SAMs. However, the versatility of organic chemistry allows for the design of SAMs with alternative organic cores that may possess specific benefits. In this study, three novel SAMs are incorporated in p‐i‐n perovskite solar cells, each based on an aromatic core commonly used in organic semiconductors. The novel SAMs vary in their energy level alignment with the perovskite active layer. Optimal alignment is achieved with a pyrene‐based SAM (4PAPyr), resulting in solar cells that outperform the commercially available 2PACz. Moreover, due to improved surface coverage, the use of 4PAPyr leads to a significantly higher number of working solar cell devices when compared to 2PACz, which is of particular interest with regard to upscaling. After device optimization, a power conversion efficiency of 22.2% is achieved with 4PAPyr. This research underlines the importance of diversifying SAMs to unlock further advancements in perovskite solar cell efficiency and scalability.

Posterior Correction and Fusion Using a 4D Anatomical Spinal Reconstruction Technique Improves Postural Stability Under the Eye-Closed Condition in Patients with Adolescent Idiopathic Scoliosis.

Background: Patients with adolescent idiopathic scoliosis (AIS) has been reported to exhibit impaired postural stability. Posterior correction and fusion using four-dimensional (4D) anatomical spinal reconstruction techniques may improve postural stability to correct the spine for optimal anatomical alignment. This prospective study aimed to determine the effect of posterior correction and fusion using a 4D anatomical spinal reconstruction technique on postural stability in the eye-open and eye-closed standing position in patients with thoracic AIS. Methods: Thirty-three patients with AIS, excluding those with Lenke type 5C AIS, participated in the study. The mean and standard deviation of the minimum values of the time-to-boundary (TTB) were determined. All patients were asked to perform the quiet standing position under the eye-open and eye-closed condition on a force plate preoperatively and at 1 week and 2 years postoperatively. The TTB value was calculated from the velocity and distance to the foot boundary of the acquired center-of-pressure data. Results: Under the eye-closed condition, the mean and standard deviation of the minimum TTB were significantly higher at 2 years postoperatively than preoperatively and at 1 week postoperatively. The mean and standard deviation of the minimum TTB values were significantly lower at 1 week postoperatively than preoperatively. Conclusions: The results of this study suggest that surgery using the 4D anatomical spinal reconstruction technique reduces postural stability immediately after surgery; however, it improves postural stability at 2 years compared to the preoperative values.

Electrospinning Aligned SF/Magnetic Nanoparticles-Blend Nanofiber Scaffolds for Inducing Skeletal Myoblast Alignment and Differentiation.

In the realm of skeletal muscle tissue engineering, anisotropic materials that emulate natural tissues show substantial promise. Electrospun scaffolds, mimicking the fibrillar structure of the extracellular matrix, are commonly employed but often fall short in achieving optimal alignment and mechanical strength. Silk fibroin has emerged as a versatile material in tissue engineering, valued for its biocompatibility, mechanical robustness, and biodegradability. However, conventional electrospinning methods of SF result in randomly oriented fibers, limiting their efficacy. In this work, we developed a straightforward method to fabricate directional tissue scaffolds using silk fibroin. By integrating a magnetic field collecting device and incorporating Fe3O4 nanoparticles into the spinning solution, we successfully produced well-aligned silk nanofiber scaffolds. These aligned fibers not only improved scaffold orientation and mechanical properties but also exhibited magnetic responsiveness. The aligned SF scaffolds effectively guided the adhesion, proliferation, and differentiation of mesenchymal stem cells along the fiber direction. Cultured on these scaffolds, myoblast C2C12 cells demonstrated oriented growth, highlighting the potential of aligned SF fibers in advancing skeletal muscle engineering for biomedical applications.