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Background: Imagination represents a pivotal capability of human intelligence. To develop human-like artificial intelligence, uncovering the computational architecture pertinent to imaginative capabilities through reverse engineering the brain's computational functions is essential. The existing Structure-Constrained Interface Decomposition (SCID) method, leverages the anatomical structure of the brain to extract computational architecture. However, its efficacy is limited to narrow brain regions, making it unsuitable for realizing the function of imagination, which involves diverse brain areas such as the neocortex, basal ganglia, thalamus, and hippocampus. Objective: In this study, we proposed the Function-Oriented SCID method, an advancement over the existing SCID method, comprising four steps designed for reverse engineering broader brain areas. This method was applied to the brain's imaginative capabilities to design a hypothetical computational architecture. The implementation began with defining the human imaginative ability that we aspire to simulate. Subsequently, six critical requirements necessary for actualizing the defined imagination were identified. Constraints were established considering the unique representational capacity and the singularity of the neocortex's modes, a distributed memory structure responsible for executing imaginative functions. In line with these constraints, we developed five distinct functions to fulfill the requirements. We allocated specific components for each function, followed by an architectural proposal aligning each component with a corresponding brain organ. Results: In the proposed architecture, the distributed memory component, associated with the neocortex, realizes the representation and execution function; the imaginary zone maker component, associated with the claustrum, accomplishes the dynamic-zone partitioning function; the routing conductor component, linked with the complex of thalamus and basal ganglia, performs the manipulation function; the mode memory component, related to the specific agranular neocortical area executes the mode maintenance function; and the recorder component, affiliated with the hippocampal formation, handles the history management function. Thus, we have provided a fundamental cognitive architecture of the brain that comprehensively covers the brain's imaginative capacities.

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This review examines a wide range of marine microbial-derived bioactive peptide molecules, emphasizing the significance of reverse engineering in their production. The discussion encompasses the advancements in Marine Natural Products (MNPs) bio-manufacturing through the integration of omics-driven microbial engineering and bioinformatics. The distinctive features of non-ribosomally synthesised peptides (NRPs), and ribosomally synthesised precursor peptides (RiPP) biosynthesis is elucidated and presented. Additionally, the article delves into the origins of common peptide modifications. It highlights various genome mining approaches for the targeted identification of Biosynthetic Gene Clusters (BGCs) and novel RiPP and NRPs-derived peptides. The review aims to demonstrate the advancements, prospects, and obstacles in engineering both RiPP and NRP biosynthetic pathways.

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Three-dimensional (3D) printing is an emerging tool for creating patient-specific tissue constructs analogous to the native tissue microarchitecture. In this study, anatomically equivalent 3D nerve conduits were developed using thermoplastic polyurethane (TPU) by combining reverse engineering and material extrusion (i.e. fused deposition modeling) technique. Printing parameters were optimized to fabricate nerve-equivalent TPU constructs. The TPU constructs printed with different infill densities supported the adhesion, proliferation, and gene expression of neuronal cells. Subcutaneous implantation of the TPU constructs for three months in rats showed neovascularization with negligible local tissue inflammatory reactions and was classified as a non-irritant biomaterial as per ISO 10993-6. To performin vivoefficacy studies, nerve conduits equivalent to rat's sciatic nerve were fabricated and bridged in a 10 mm sciatic nerve transection model. After four months of implantation, the sensorimotor function and histological assessments revealed that the 3D printed TPU conduits promoted the regeneration in critical-sized peripheral nerve defects equivalent to autografts. This study proved that TPU-based 3D printed nerve guidance conduits can be created to replicate the complicated features of natural nerves that can promote the regeneration of peripheral nerve defects and also show the potential to be extended to several other tissues for regenerative medicine applications.

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The dimensional accuracy of additively manufactured (3D printed) medical models can be affected by various parameters. Although different methods are used to evaluate the accuracy of additively manufactured models, this study focused on the investigation of the dimensional accuracy of the medical model based the combination of reverse engineering (RE) and additive manufacturing (AM) technologies. Human femur bone was constructed from CT images and manufactured, using Fortus 450mc Industrial material extrusion 3D Printer. The additive manufactured femur bone was subsequently 3D scanned using three distinct non-contact 3D scanners. MeshLab was used for mesh analysis, while VX Elements was used for post-processing of the point cloud. A combination of the VX Inspect environment and MeshLab was used to evaluate the scanning performance. The deviation of the 3D scanned 3D models from the reference mesh was determined using relative metrics and absolute measurements. The scanners reported deviations ranging from -0.375 mm to 0.388 mm, resulting in a total range of approximately 0.763 mm with average root mean square (RMS) deviation of 0.22 mm. The results indicate that the additively manufactured model, as measured by 3D scanning, has a mean deviation with an average range of approximately 0.46 mm and an average mean value of around 0.16 mm.

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Reverse engineering is applied to identify optimum polymerization conditions for the synthesis of polymers with pre-defined properties. The proposed approach uses multi-objective optimization (MOO) and provides multiple candidate polymerization procedures to achieve the targeted polymer property. The objectives for optimization include the maximal similarity of molar mass distributions (MMDs) compared to the target MMDs, a minimal reaction time, and maximal monomer conversion. The method is tested for vinyl acetate radical polymerizations and can be adopted to other monomers. The data for the optimization procedure are generated by an in-house-developed kinetic Monte-Carlo (kMC) simulator for a selected recipe search space. The proposed reverse engineering algorithm comprises several steps: kMC simulations for the selected recipe search space to derive initial data, performing MOO for a targeted MMD, and the identification of the Pareto optimal space. The last step uses a weighted sum optimization function to calculate the weighted score of each candidate polymerization condition. To decrease the execution time, clustering of the search space based on MMDs is applied. The performance of the proposed approach is tested for various target MMDs. The suggested MOO-based reverse engineering provides multiple recipe candidates depending on competing objectives.

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The cigarette filter is an essential component of modern cigarettes and studying the flow distribution within the cigarette filter is of great significance in reducing the harm of cigarettes and optimizing smoking sensations. As the object of numerical simulation research, a three-dimensional model of the cigarette was accurately constructed through micro-CT reverse engineering, achieving a scanning accuracy of 4.05 µm. An overall porous media model of the cigarette filter was established to characterize the pressure distribution inside the filter. Based on the three-dimensional reconstruction, a local simulation model of the cavity-filtered filter was created by extracting a 1/36 geometric model. The simulation results of the overall porous media model of the cigarette filter were used as the pressure boundary conditions for the local simulation model of the cavity-filtered filter, and the effects of the wrapped paper and cavity on the flow field were analyzed. The results show that the simulated pressure drop in the overall porous media model of the cigarette filter had a deviation of less than 3.5% compared to the experimental results. This suggests that the porous media model can effectively predict the changes in pressure drop within the filter. When both wrapped paper and cavity were present, the velocity at the interface between acetate fiber and wrapped paper increased by 141.54%, while the pressure approached 0 Pa. Similarly, at the interface between acetate fiber and cavity, the velocity increased by 130.77%. It indicates that both wrapped paper and cavity significantly influenced the flow field characteristics within the cigarette filter. Additionally, as the porosity of the wrapped paper gradually increased from 0.69 to 0.99 in the radial direction, the fluid velocity increased by 14.46%, while the fluid pressure decreased by 29.09%. These changes were particularly evident when the porosity was below 0.87.

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iPhone operating system (iOS) devices utilize binary cookies as a data storage tool, encoding user-specific information within an often-neglected element of smartphone analysis. This binary format contains details such as cookie flags, expiration, and creation dates, domain, and value of the cookie. These data are invaluable for forensic investigations. This study presents a comprehensive methodology to decode and extract valuable data from these files, enhancing the ability to recover user activity information from iOS devices. This paper provides an in-depth forensic investigation into the structure and function of iOS binary cookie files. Our proposed forensic technique includes a combination of reverse engineering and custom-built Python scripts to decode the binary structure. The results of our research demonstrate that these cookie files can reveal an array of important digital traces, including user preferences, visited websites, and timestamps of online activities. It concludes that the forensic analysis of iOS binary cookie files can be a tool for forensic investigators and cybersecurity professionals. In the rapidly evolving domain of digital forensics, this research contributes to our understanding of less-explored data sources within iOS devices and their potential value in investigative contexts.

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Despite recent remarkable advances in binary code analysis, malware developers still use complex anti-reversing techniques that make analysis difficult. Packers are used to protect malware, which are (commercial) tools that contain diverse anti-reversing techniques, including code encryption, anti-debugging, and code virtualization. In this study, we present UnSafengine64: a Safengine unpacker for 64-bit Windows. UnSafengine64 can correctly unpack packed executables using Safengine, which is considered one of the most complex commercial packers in Windows environments; to the best of our knowledge, there have been no published analysis results. UnSafengine64 was developed as a plug-in for Pin, which is one of the most widely used dynamic analysis tools for Microsoft Windows. In addition, we utilized Detect It Easy (DIE), IDA Pro, x64Dbg, and x64Unpack as auxiliary tools for deep analysis. Using UnSafengine64, we can analyze obfuscated calls for major application programming interface (API) functions or conduct fine-grained analyses at the instruction level. Furthermore, UnSafengine64 detects anti-debugging code chunks, captures a memory dump of the target process, and unpacks packed files. To verify the effectiveness of our scheme, experiments were conducted using Safengine 2.4.0. The experimental results show that UnSafengine64 correctly executes packed executable files and successfully produces an unpacked version. Based on this, we provided detailed analysis results for the obfuscated executable file generated using Safengine 2.4.0.

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The presented data is based on investigations carried out in the framework of the European RFCS (Research Fund for Coal and Steel) funded project HOLLOSSTAB (2016-2019). The campaign's overall goal is presented in more detail in [1] and [2]. The experiments were performed in the Structural Laboratory at the Bundeswehr University Munich to investigate the cross-section behavior of cold-formed square and rectangular hollow sections (SHS and RHS). Two grades of mild and high-strength steel (S355 and S500) and seven section sizes were examined. The profiles cover all four cross-section classes according to EN1993-1-1 [3]. Monotonic stub column, short beam, and long-beam column tests were performed to investigate the load-bearing capacity. The outputs were load-deformation curves for each specimen. The experimental tests were accomplished by digital image correlation (DIC) to obtain an overview of the full deformation field in the specimens. Recalculations with advanced FE-shell simulations, based on scanned specimen geometries (spatial 3D point clouds) and nonlinear material models obtained from tensile coupon tests, were modeled to reproduce the real behavior obtained during the tests.

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Efficient utilization of galactose by microorganisms can lead to the production of valuable bio-products and improved metabolic processes. While Bacillus subtilis has inherent pathways for galactose metabolism, there is potential for enhancement via evolutionary strategies. This study aimed to boost galactose utilization in B. subtilis using adaptive laboratory evolution (ALE) and to elucidate the genetic and metabolic changes underlying the observed enhancements. The strains of B. subtilis underwent multiple rounds of adaptive laboratory evolution (approximately 5000 generations) in an environment that favored the use of galactose. This process resulted in an enhanced specific growth rate of 0.319 ± 0.005 h-1, a significant increase from the 0.03 ± 0.008 h-1 observed in the wild-type strains. Upon selecting the evolved strain BSGA14, a comprehensive whole-genome sequencing revealed the presence of 63 single nucleotide polymorphisms (SNPs). Two of them, located in the coding sequences of the genes araR and glcR, were found to be the advantageous mutations after reverse engineering. The strain with these two accumulated mutations, BSGALE4, exhibited similar specific growth rate on galactose to the evolved strain BSGA14 (0.296 ± 0.01 h-1). Furthermore, evolved strain showed higher productivity of protease and ß-galactosidase in mock soybean biomass medium. ALE proved to be a potent tool for enhancing galactose metabolism in B. subtilis. The findings offer valuable insights into the potential of evolutionary strategies in microbial engineering and pave the way for industrial applications harnessing enhanced galactose conversion.

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In K-12 STEM education, engineering design is emphasized, as demonstrated by the bridge-design project. Due to the iterative nature of engineering design, engineering practice is frequently complicated and requires pedagogical guidance. As an emerging pedagogy in STEM education, REP (Reverse Engineering Pedagogy) is showing, but not enough, some benefits in several cases. This paper aims to explore the effects of REP in a bridge-design course. A comparison experiment, REP versus PBL (Project-Based Learning), was conducted by randomly forming two groups of fourth-grade students from a primary school in China. Results indicated that REP was more advantageous than PBL in terms of decreasing students' cognitive load, boosting their scientific knowledge level and engineering design skills. However, REP and PBL have the same effect on the students' learning attitude and engagement. The key findings, possible reasons, and suggestions for practice are also discussed.

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In recent years, the Internet of Things (IoT) paradigm has been widely applied across a variety of industrial and consumer areas to facilitate greater automation and increase productivity. Higher dependability on connected devices led to a growing range of cyber security threats targeting IoT-enabled platforms, specifically device firmware vulnerabilities, often overlooked during development and deployment. A comprehensive security strategy aiming to mitigate IoT firmware vulnerabilities would entail auditing the IoT device firmware environment, from software components, storage, and configuration, to delivery, maintenance, and updating, as well as understanding the efficacy of tools and techniques available for this purpose. To this effect, this paper reviews the state-of-the-art technology in IoT firmware vulnerability assessment from a holistic perspective. To help with the process, the IoT ecosystem is divided into eight categories: system properties, access controls, hardware and software re-use, network interfacing, image management, user awareness, regulatory compliance, and adversarial vectors. Following the review of individual areas, the paper further investigates the efficiency and scalability of auditing techniques for detecting firmware vulnerabilities. Beyond the technical aspects, state-of-the-art IoT firmware architectures and respective evaluation platforms are also reviewed according to their technical, regulatory, and standardization challenges. The discussion is accompanied also by a review of the existing auditing tools, the vulnerabilities addressed, the analysis method used, and their abilities to scale and detect unknown attacks. The review also proposes a taxonomy of vulnerabilities and maps them with their exploitation vectors and with the auditing tools that could help in identifying them. Given the current interest in analysis automation, the paper explores the feasibility and impact of evolving machine learning and blockchain applications in securing IoT firmware. The paper concludes with a summary of ongoing and future research challenges in IoT firmware to facilitate and support secure IoT development.

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Symmetries and tunability are of fundamental importance in wave scattering control, but symmetries are often obvious upon visual inspection, which constitutes a significant vulnerability of metamaterial wave devices to reverse-engineering risks. Here, it is theoretically and experimentally shown that a symmetry in the reduced basis of the "primary meta-atoms" that are directly connected to the outside world is sufficient; meanwhile, a suitable topology of non-local interactions between them, mediated by the internal "secondary" meta-atoms, can hide the symmetry from sight in the canonical basis. Covert symmetry-based scattering control in a cable-network metamaterial featuring a hidden parity ( P $\mathcal {P}$ ) symmetry in combination with hidden- P $\mathcal {P}$ -symmetry-preserving and hidden- P $\mathcal {P}$ -symmetry-breaking tuning mechanisms is experimentally demonstrated. Physical-layer security in wired communications is achieved using the domain-wise hidden P $\mathcal {P}$ -symmetry as a shared secret between the sender and the legitimate receiver. Within the approximation of negligible absorption, the first tuning of a complex scattering metamaterial without mirror symmetry to feature exceptional points (EPs) of PT $\mathcal {PT}$ -symmetric reflectionless states, as well as quasi-bound states in the continuum, is reported. These results are reproduced in metamaterials involving non-reciprocal interactions between meta-atoms, including the first observation of reflectionless EPs in a non-reciprocal system.

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Mollusks, as well as many other living organisms, have the ability to shape mineral crystals into unconventional morphologies and to assemble them into complex functional mineral-organic structures, an observation that inspired tremendous research efforts in scientific and technological domains. Despite these, a biochemical toolkit that accounts for the formation of the vast variety of the observed mineral morphologies cannot be identified yet. Herein, phase-field modeling of molluscan nacre formation, an intensively studied biomineralization process, is used to identify key physical parameters that govern mineral morphogenesis. Manipulating such parameters, various nacre properties ranging from the morphology of a single mineral building block to that of the entire nacreous assembly are reproduced. The results support the hypothesis that the control over mineral morphogenesis in mineralized tissues happens via regulating the physico-chemical environment, in which biomineralization occurs: the organic content manipulates the geometric and thermodynamic boundary conditions, which in turn, determine the process of growth and the form of the biomineral phase. The approach developed here has the potential of providing explicit guidelines for the morphogenetic control of synthetically formed composite materials.

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As a renewable energy from biomass, isobutanol is considered as a promising alternative to fossil fuels. To biotechnologically produce isobutanol, strain development using industrial microbial hosts, such as Escherichia coli, has been conducted by introducing a heterologous isobutanol synthetic pathway. However, the toxicity of produced isobutanol inhibits cell growth, thereby restricting improvements in isobutanol titer, yield, and productivity. Therefore, the development of robust microbial strains tolerant to isobutanol is required. In this study, isobutanol-tolerant mutants were isolated from two E. coli parental strains, E. coli BL21(DE3) and MG1655(DE3), through adaptive laboratory evolution (ALE) under high isobutanol concentrations. Subsequently, 16 putative genes responsible for isobutanol tolerance were identified by transcriptomic analysis. When overexpressed in E. coli, four genes (fadB, dppC, acs, and csiD) conferred isobutanol tolerance. A fermentation study with a reverse engineered isobutanol-producing E. coli JK209 strain showed that fadB or dppC overexpression improved isobutanol titers by 1.5 times, compared to the control strain. Through coupling adaptive evolution with transcriptomic analysis, new genetic targets utilizable were identified as the basis for the development of an isobutanol-tolerant strain. Thus, these new findings will be helpful not only for a fundamental understanding of microbial isobutanol tolerance but also for facilitating industrially feasible isobutanol production.

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BACKGROUND: Understanding gene regulatory networks (GRNs) is essential for unraveling the molecular mechanisms governing cellular behavior. With the advent of high-throughput transcriptome measurement technology, researchers have aimed to reverse engineer the biological systems, extracting gene regulatory rules from their outputs, which represented by gene expression data. Bulk RNA sequencing, a widely used method for measuring gene expression, has been employed for GRN reconstruction. However, it falls short in capturing dynamic changes in gene expression at the level of individual cells since it averages gene expression across mixed cell populations. OBJECTIVE: In this review, we provide an overview of 15 GRN reconstruction tools and discuss their respective strengths and limitations, particularly in the context of single cell RNA sequencing (scRNA-seq). METHODS: Recent advancements in scRNA-seq break new ground of GRN reconstruction. They offer snapshots of the individual cell transcriptomes and capturing dynamic changes. We emphasize how these technological breakthroughs have enhanced GRN reconstruction. CONCLUSION: GRN reconstructors can be classified based on their requirement for cellular trajectory, which represents a dynamical cellular process including differentiation, aging, or disease progression. Benchmarking studies support the superiority of GRN reconstructors that do not require trajectory analysis in identifying regulator-target relationships. However, methods equipped with trajectory analysis demonstrate better performance in identifying key regulatory factors. In conclusion, researchers should select a suitable GRN reconstructor based on their specific research objectives.

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BACKGROUND:Three-point mechanics is an effective method for ankle foot orthosis correction and prevention of various foot diseases.At present,the clinical application research on 3D printing ankle foot orthosis has been widespread;however,there are relatively few reports on numerical simulation and finite element analysis involving three-point mechanical correction.There is a lack of relevant biomechanical experimental verification. OBJECTIVE:Three-point force was loaded to analyze the composite model of ankle foot orthosis and foot by finite element method,observing the effect of foot correction with ankle foot orthosis under three-point force intervention,verifying the effectiveness of three-point force and the reliability of ankle foot orthosis. METHODS:A three-dimensional foot and ankle model of a healthy volunteer was constructed based on the medical image processing software Mimics.Rodin 4D and Geomagic reverse engineering software were used to optimize the models and design personalized ankle foot orthosis models.Solidworks software was utilized to turn the ankle model inside for 10° to simulate the foot varus disease.Static loading was carried out on the foot force application area by ANSYS software combined with the three-point mechanics principle.The deformation and stress changes of the foot and ankle tissues were analyzed when the human foot pain threshold was met.The display dynamics was used to further verify the effectiveness of the three-point force applied by the ankle foot orthosis. RESULTS AND CONCLUSION:(1)The personalized ankle foot orthosis designed in this paper had the effect of preventing and fixing foot and ankle varus.The ankle varus was 1.81 mm after being loaded with 1 N·m of varus when not wearing ankle foot orthosis,while it was only 0.44 mm after wearing ankle foot orthosis,the deformation rate was reduced by 75.7%,and the effect of preventing varus was significantly enhanced.(2)When only coronal correction was performed,the low calcaneal force would aggravate the varus angle of the front foot.After adjusting the correction force on the inside of the heel and above the medial malleolus,the varus angle of the front foot and the calcaneus position were improved;however,the medial phalangeal region of the foot still had different degrees of adduction and displacement,which would aggravate the adduction deformity of the patient's front foot.(3)The correction effect of the coronal plane and horizontal plane was better than that of the single coronal plane.There was no adduction and displacement of the medial phalanges of the front foot and the varus angle of the front foot decreased under the force(25,10,10,20 N)of the medial heel,the medial shaft of the first metatarsal,below the lateral malleolus and above the medial malleolus,and the valgus along the X-axis was corrected by 1.395 mm,the calcaneus valgus was corrected by 1.227 mm.The calcaneus varus angle was corrected from 10.21° to 7.25°,and the varus angle was improved by 28.9%.(4)The lateral plantar metatarsal load decreased,the medial plantar metatarsal load increased under the action of a two-plane three-point force,and the plantar bone stress was significantly improved after correction.Thus,the reliability of the three-point force principle was further verified.This study provides an important theoretical support for the implementation of ankle foot orthosis in the treatment of varus in clinical practice.

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Objective:To investigate the application of digital scanning combined with reverse engineering technology in the teaching of full crown preparation.Methods:A total of 30 undergraduate students in the fifth grade of stomatology were selected from Shantou University Medical College and were divided into experimental group and control group using a random number table. Two resin teeth were distributed to each student and were placed on dental head simulators to perform full crown preparation. The students in the control group received teaching with analogies of experience, and those in the experimental group received teaching with digital scanning, i.e., full crown preparation for the second time after digital scanning for the first time of full crown preparation. The score was determined based on China Stomatological Association Standards: Guideline for the tooth preparation of dental ceramic crowns (T/CHSA 008—2023), with a total score of 100 points. SAS9.4 software was used for the two-independent-samples t test and the paired t-test, and the Kendall W concordance coefficient was used to investigate the consistency of evaluators. Results:There were significant changes after teaching in the preparation scores of the right maxillary central incisor (76.27 pre-demonstration vs. 84.70 post-demonstration, P<0.001) and the right maxillary first molar (72.10 pre-demonstration vs. 82.37 post-demonstration, P<0.001). Compared with the control group, the experimental group had a significant increase in the mean preparation score of the right maxillary first molar (14.00 vs. 6.53, t=2.64, P=0.014). In the experimental group, there were significant increases in the preparation scores of the right maxillary first molar for the occlusal surface (15.40 pre-demonstration vs. 19.33 post-demonstration, P<0.001), the buccolingual surface (18.13 pre-demonstration vs. 20.87 post-demonstration, P=0.016), and the proximal surface (12.40 pre-demonstration vs. 14.07 post-demonstration, P=0.004), as well as significant increases in the scores of the convergence angles of the buccolingual surface (2.80 pre-demonstration vs. 4.07 post-demonstration, P=0.004) and the proximal surface (3.47 pre-demonstration vs. 4.47 post-demonstration, P=0.008). Conclusions:Application of digital teaching for difficult crown preparation of posterior teeth can effectively improve the quality of crown preparation among students, standardize the teaching process of crown preparation, and increase the precision of crown preparation, thereby laying a foundation for promoting uniformity in talent cultivation for dental prosthodontics.

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In recent years, 3D printing (3DP) has advanced traditional medical treatments. This review explores the fusion of reverse engineering and 3D printing of medical implants, with a specific focus on drug delivery applications. The potential for 3D printing technology to create patient-specific implants and intricate anatomical models is discussed, along with its ability to address challenges in medical treatment. The article summarizes the current landscape, challenges, benefits, and emerging trends of using 3D-printed formulations for medical implantation and drug delivery purposes.