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Training a deep learning inversion network usually requires hundreds of thousands of complex velocity models, which is labor-intensive and expensive to acquire. In this work, we develop a new framework to automatically generate various velocity models with common geological structures, such as folding layers, faults and salt bodies. There are three main modules in the proposed framework. The first module generates a folded model with a given number of layers; the other two modules can add faults and salt bodies onto the folded model to form a fault or salt model, respectively. To best simulate the shape of subsurface geological structures while ensuring a good application effect in deep learning inversion, we generate the structural model based on composition of several basic functions with recommended parameter ranges. Then the generated structural model will be assigned with velocity values based on assumptions of underground seismic velocity distribution. To investigate the application effect of the generated 3D models, we conduct a deep learning inversion test. Since currently there is no 3D deep learning inversion algorithms available, the latest 2D inversion network called SeisInvNet is used to test the feasibility of the randomly generated velocity models. Through the experiments, we can see that the 2D inversion results are consistent with the true models from the aspects of velocity values and geological structure shapes, which demonstrates the rationality of the designed 3D models. In the end, we further discuss the feasibility of applying the proposed 3D model dataset to train a 3D inversion network. This work paves the way for the development of 3D deep learning inversion methods.

Abstract Background Classification of the spinal deformity in adolescent idiopathic scoliosis (AIS) remains two-dimensional (2D) as the spinal radiographs remain the mainstay in clinical evaluation of the disease. 3D classification systems are proposed, however are time consuming. We here aim to evaluate the clinical application of a 3D classification system by the use of only posterior-anterior and lateral radiographs in Lenke 1 adolescent idiopathic scoliosis (AIS). Methods Forty Lenke 1 AIS were classified by five observers following a three-step flowchart, developed based on our previous 3D classification system. This 3D classification characterizes the curve in the frontal and sagittal views and infers the third dimension with rules based on prior data to determine the 3D subtypes of the curve. Repeated rating was performed for 20 randomly selected patients in the same cohort. In addition to the classification by the raters, the 3D model of the spines were generated to determine the actual curve subtype based on the algorithm that was originally used to develop the 3D classification system. The interobserver and intraobserver reliability and the classification accuracy were determined for both 3D and axial classifications of the cohort. Results The interobserver reliability was moderate to strong with a kappa value between 0.61–0.89 for 3D and axial classifications. Comparing the mathematical classification and the raters’ classification, the classification accuracy among all raters ranged between 56 and 89%. Conclusion We evaluated the reliability of a previously developed 3D classification system for Lenke 1 AIS patients when only two-view spinal radiographs are available. Radiologists and orthopedic surgeons were able to identify the 3D subtypes of Lenke 1 AIS from the patients’ radiographs with moderate to strong reliability. The new 3D classification has the potential to identify the subtypes of the Lenke 1 AIS without a need for quantitative 3D image post-processing.

Finite element (FE) modeling plays a well-established and increasingly significant role in analyses of articular cartilage at the organ, tissue, and cell scales: for example understanding the functional relationships among constituents, microstructure, and tissue function in diarthrodial joints. A constitutive model, the crux of an accurate FE model, formalizes the functional dependencies among physical variables (e.g., strain, stress, and energy), thereby providing the missing equations to close the system generated by the classical balance principals, while accounting for the specific behavior of cartilage. In the future, fully 3-D FE modeling of cartilage could provide clinical diagnostic tools for patient-specific analyses. Computational analyses of full, patient-specific knee joints under load, especially before and after surgical intervention, would facilitate: (1) investigating fundamental research questions, e.g., structure-function relationships, load support, and mechanobiological cellular stimuli; (2) assessing individual patients, e.g., assessing joint integrity, preventing damage, and prescribing therapies; and (3) advancing tissue engineering, i.e., building replacement materials for cartilage. Approaches to computational modeling generally aim to adopt the simplest possible formulation that can describe experimental data, yet the complexity of articular cartilage mechanics demands similarly complex models. This review discusses extant multi-phase, large-strain (i.e., finite-deformation) constitutive models for cartilage which have been implemented in 3-D nonlinear finite elements. These have paved the way toward 3-D patient-specific clinical tools and along with advances in the underlying continuum theories and computational methods provide the foundations of improved constitutive models for 3-D FE modeling of cartilage in the future. [ABSTRACT FROM AUTHOR]

Objectives: Semiautomatic fractional limb volume (FLV) models have recently produced promising results for fetal birth weight (BW) estimation. We tested those models in a more unselected population hypothesizing that the FLV models would improve accuracy and precision of fetal BW estimation compared to the Hadlock model. Methods: We compared the performance of different BW prediction models: Hadlock (biparietal diameter [BPD], abdominal circumference (AC), femur diaphysis length) and modified Lee thigh volume (TVol) and arm volume (AVol) (BPD, AC, automated fractional TVol, and AVol). Accuracy (systematic errors, mean percent differences) and precision (random errors, ± 1 SD of percent differences) were calculated. Results: A total of 75 fetuses were included for final analysis. The Hadlock model showed the most consistent results with accurate BW estimation not significantly different from zero (−0.37 ± 8.53%). The modified fractional thigh and arm volume models were less accurate but trended toward more precise results (−2.63 ± 7.69% and −3.85 ± 7.47%, respectively). In addition, the modified TVol model showed the trend to predict more BWs within ±10% of the actual BW compared to the Hadlock model (81.3 versus 74.67%, ns). Conclusions: Based on our results, fetal weight estimation using the modified semiautomatic FLV models generates less accurate results in third‐trimester fetuses compared to the Hadlock model. Those models recently published might improve the results of BW prediction by showing a higher precision than conventional models, especially in small and large fetuses. Further studies are needed to investigate the clinical usefulness of the new models. [ABSTRACT FROM AUTHOR]

Transesophageal echocardiography (TEE) has experienced tremendous increase in interest and demand alongside the rapid growth of transcatheter structural cardiac interventions. TEE instruction prolongs the procedure, increasing the risk of probe malfunction from overheating and patient complications from prolonged sedation. Echocardiographic simulation programs have been developed to hone the procedural skills of novice operators in a time‐unrestricted, low‐pressure environment before they perform TEEs on real patients. Simulators likely benefit training in interventional TEE for the same reasons. We searched PubMed, basic Google, and Google Scholar for currently marketed TEE simulators, including foreign as well as US companies. We queried the vendors regarding features of the simulators that pertain to effective instructional design for diagnostic TEE. We also queried regarding the simulators' applicability to training in interventional TEE. The vendors' responses are reported here. In addition, we discuss the specific training needs for structural heart interventions, for which echocardiographic simulation could be a powerful educational tool. Lastly, we discuss the role of simulation for formative and summative assessment, and the advances required to improve training in complex procedures within the field of interventional echocardiography. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to compare the upper airway space changes after miniscrew-anchored maxillary protraction with hybrid (HH) and conventional hyrax (CH) expanders. Material and methods: The sample comprised Class III malocclusion growing patients that were randomized into two groups of miniscrew-anchored maxillary protraction. The group HH was treated with a hybrid hyrax appliance in the maxilla and two miniscrews distally to the canines in the mandible. Class III elastics were used from the maxillary first molar to the mandibular miniscrews until anterior crossbite correction. The group CH was treated with a similar protocol except for the conventional hyrax expander in the maxilla. Cone-beam computed tomography was obtained before (T1) and after 12 months of therapy (T2). The shape and size of upper airway were assessed. Intergroup comparisons were performed using Mann-Whitney U test (p < 0.05). Results: The group HH was composed of 20 patients (8 female, 12 male) with a mean age of 10.76 years. The group CH was composed of 15 patients (6 female, 9 male) with a mean age of 11.52 years. Anteroposterior and transverse increases of the upper airway were found for both groups. The oropharynx and the most constricted area increased similarly in both groups. Conclusions: No differences in upper airway changes were observed using protraction anchored on hybrid or conventional hyrax expanders. Clinical relevance: Maxillary protraction anchored on hybrid or conventional hyrax expanders may benefit patients with breathing disorders due to the increase of the upper airway volume and most constricted area. Registration: ClinicalTrials.gov (NCT03712007). [ABSTRACT FROM AUTHOR]

This study concerns the three-dimensional hybrid nanofluid flow and heat transfer due to a deformable (stretching/shrinking) plate with power-law velocity and orthogonal surface shear. The flow due to the shrinking sheet is maintained with the imposition of wall mass suction. The effect of adding Cu and Al2O3 nanoparticles are represented by a homogeneous mixture model with the modified thermophysical properties. Two types of thermophysical properties for hybrid nanofluids are discussed and compared in this interesting work. The three-dimensional model is then, reduced into a relevant set of ordinary differential equations using similarity transformation. The results are generated using the bvp4c solver and presented in the tables and graphs. Duality of solutions are observed in both stretching and shrinking regions, however, only the first solution is proved to be stable and realistic. Surprisingly, the heat transfer rate augments when the power law velocity is used. The hybrid nanofluid with an upsurge of copper volume fraction also reduces the rate of heat transfer.

Purpose The use of three-dimensional (3D) thoracoscope provides improved depth perception and accuracy in video-assisted thoracoscopic surgery (VATS). This study aimed to compare the surgical outcomes between two-dimensional (2D) and 3D VATS lobectomy for stage I lung cancer. Methods From January 2013 to May 2018, 354 patients underwent VATS lobectomy and mediastinal lymph node dissection for clinical stage I lung cancer. The 3D VATS system was introduced in July 2016 in our center. A total of 182 patients underwent 2D VATS lobectomy from January 2013 to June 2016, and 172 patients underwent 3D VATS lobectomy from July 2016 to May 2018. Results The thoracotomy conversion rate was lower (1.2% vs. 6.4%, P= 0.011) in the 3D VATS group than in the 2D VATS group. Operation time (mean: 119.0 minutes vs. 151.4 minutes, P< 0.001), operative blood loss (median: 100 mL vs. 150 mL, P< 0.001), and length of hospital stay after surgery (median: 5 days vs. 6 days, P< 0.001) were significantly lower in the 3D VATS group than in the 2D VATS group. A higher number of lymph nodes was resected in 3D VATS (mean: 15.9 vs. 13.8, P= 0.006). No significant difference was observed between 3D and 2D VATS in terms of operative complications (Clavien-Dindo classification grade ≥ 1; 14.7% vs. 14.6%, P= 0.322). None of the patients died postoperatively. Conclusion Our retrospective data showed that the 3D thoracoscope had better surgical outcomes than 2D thoracoscope for VATS lobectomy in patients with clinical stage I lung cancer.

Background The glenoid version of the shoulder joint correlates with the stability of the glenohumeral joint and the clinical results of total shoulder arthroplasty. We sought to analyze and compare the glenoid version measured by traditional axial two-dimensional (2D) computed tomography (CT) and three-dimensional (3D) reconstructed images at different levels. Methods A total of 30 cases, including 15 male and 15 female patients, who underwent 3D shoulder CT imaging was randomly selected and matched by sex consecutively at one hospital. The angular difference between the scapular body axis and 2D CT slice axis was measured. The glenoid version was assessed at three levels (midpoint, upper one-third, and center of the lower circle of the glenoid) using Friedman’s method in the axial plane with 2D CT images and at the same level of three different transverse planes using a 3D reconstructed image. Results The mean difference between the scapular body axis on the 3D reconstructed image and the 2D CT slice axis was 38.4°. At the level of the midpoint of the glenoid, the measurements were 1.7°±4.9° on the 2D CT images and −1.8°±4.1° in the 3D reconstructed image. At the level of the center of the lower circle, the measurements were 2.7°±5.2° on the 2D CT images and −0.5°±4.8° in the 3D reconstructed image. A statistically significant difference was found between the 2D CT and 3D reconstructed images at all three levels. Conclusions The glenoid version is measured differently between axial 2D CT and 3D reconstructed images at three levels. Use of 3D reconstructed imaging can provide a more accurate glenoid version profile relative to 2D CT. The glenoid version is measured differently at different levels.

Aims: To analyze the accuracy of a three-dimensional (3D) laser scanner-GOM® (Gesellschaft für Optische; Messtechnik, Braunschweig Germany) model-ATOS triple II optical Scanner (Advanced topometric Sensor) in examination and identification of experimental bite marks (BM) in chocolate using Styrofoam exemplar (SE). Materials and Methods: The study was conducted with 25 volunteers from whom the dental cast exemplar (CE), SE, and experimental BMs in chocolate, were made. These were then digitized using the GOM® ATOS optical scanner and 3D models were generated using GOM® ATOS software. Data analysis was performed using independent t-test for inferential statistics. Results: On 3D analysis, the experimental BM matched with the presumed biters correctly using both SE and CE. The mean percentage matching of BM vs SE was found to be 92.55 ± 1.757, and in BM vs CE, the mean matching percentage was found to be 96.09 ± 1.311. Statistical analysis of the data was obtained using independent t-test, and the mean difference in percentage matching was significant (P < 0.05) Conclusion: Three-dimensional BM analysis using 3D optical scanner proved to be a reliable, accurate, and permanent method of documentation compared to the conventional two-dimensional methods.

Mesenchymal stem cells in the dental tissue indicate a disposition for differentiation into diverse dental lineages and contain enormous potential as the important means for regenerative medicine in dentistry. Among various dental tissues, the dental pulp contains stem cells, progenitor cells and odontoblasts for maintaining dentin homeostasis. The conventional culture of stem cells holds a limit as the living tissue constitutes the three-dimensional (3D) structure. Recent development in the organoid cultures have successfully recapitulated 3D structure and advanced to the assembling of different types. In the current study, the protocol for 3D explant culture of the human dental pulp tissue has been established by adopting the organoid culture. After isolating dental pulp from human tooth, the intact tissue was placed between two layers for Matrigel with addition of the culture medium. The reticular outgrowth of pre-odontoblast layer continued for a month and the random accumulation of dentin was observed near the end. Electron microscopy showed the cellular organization and in situ development of dentin, and immunohistochemistry exhibited the expression of odontoblast and stem cell markers in the outgrowth area. Three-dimensional explant culture of human dental pulp will provide a novel platform for understanding stem cell biology inside the tooth and developing the regenerative medicine.

The high expense, poor stability, and low abundance of platinum (Pt) catalysts on earth greatly handicaps its further application. Alloying Pt with other metals is an alternate idea, however, as a promising catalyst should be synthesized on a large scale, one important goal is that the morphologies and electrocatalytic activities of the as‐obtained electrocatalysts can maintain the same, even when the precursor ratio is varied. In addition, according to the Le Chatellier's principle as more earth‐abundant precursors were used can accelerate the transforming efficiency of noble metal during the synthesis. Unfortunately, no current research has reached this goal, we herein report a facile two‐step method for the synthesis of three‐dimensional CuPt alloys via galvanic replacement between the noble Pt precursor and pre‐synthesized copper (Cu) nanocubes in a liquid system free of capping agent. Further investigation proved that the morphologies can be regulated via changing the reaction temperature, while the composition of precursors does not affect the morphologies evolutions match well with the industrial demand. The CuPt alloys obtained at 80 °C (denoted as CuPt‐80) exhibited superior activities towards both HER and MOR reaction when compared with CuPt‐60, CuPt‐100, Pt nanocrystals (Pt NCs) and 20% Pt/C. This work enriched the application of Le Chatellier's principle and provides a promising way for the rational design and synthesis of efficient and robust catalysts for sustainable energy conversion. [ABSTRACT FROM AUTHOR]

Introduction: Few studies have compared the relationship of MSV in the different craniofacial patterns. Hence, the purpose of this research was to evaluate maxillary sinus volume in different craniofacial patterns using cone-beam computed tomography. Materials and methods: This cross-sectional study included 100 pre-orthodontic patients mean aged 26.40 ± 6.77 (age ranged 21–64) years divided into different anteroposterior and vertical skeletal groups. From the cone beam computed tomography images using MIMICS 14.1 software, three-dimensional image of the maxillary sinus was constructed, and its volume was calculated. Results: The mean maxillary sinus volume was 20,279.50 ± 7800.33 mm3. Among the anteroposterior skeletal groups, the mean maxillary sinus volume in skeletal Class II group is significantly larger than class III group (P < 0.05). Among the vertical skeletal groups, High-angle groups tend to have the largest maxillary sinus volume, though there were no significant differences among the groups (P > 0.05). Similarly, males have significantly larger maxillary sinus volume than females (P < 0.05). There was a positive correlation between ANB and maxillary sinus volume (P < 0.01). Conclusion: Maxillary sinus volume is significantly larger in skeletal class II than in skeletal class III group and in males than in females (P < 0.05). These inferences have several implications in orthodontics, endodontics and oral surgery. [ABSTRACT FROM AUTHOR]

Landslide is a uniquely dynamic large-deformation process that can present serious threat to human lives and infrastructures. The natural soil properties often exhibit inherent spatial variability, which affects the landslide behavior significantly. This paper focuses on combined Monte Carlo simulation and three-dimensional (3D) dynamic large-deformation finite-element (LDFE) analysis using the coupled Eulerian-Lagrangian method to investigate the whole runout process of landslide induced by the earthquake in spatially varying soil. The results from LDFE analysis show that the mean value of runout distance in spatially varying soil is significantly higher than that of the deterministic value obtained from a homogeneous slope due to the slope failure developed along the weakest path in soils. The mean runout distance increases and converges with increasing slope length in 3D-LDFE stochastic analysis. The advantages and necessities of 3D-LDFE analysis were illustrated by comparing it with two-dimensional (2D) LDFE analysis of landslide in spatially varying soil. The results show that the calculated mean runout distance using 3D-LDFE method is at least 16.1% higher than that calculated using 2D-LDFE analysis. Finally, a linear regression formula was established to estimate the mean runout distance of landslide due to horizontal inertia acceleration. Such a formula may facilitate the risk assessment of landslide in practical engineering. [ABSTRACT FROM AUTHOR]

Introduction: Hypopituitarism is a rare, often underdiagnosed, complex hormonal disease caused by the decreased secretion of one or more hormones in the pituitary gland. The present study was designed to assess left ventricular (LV) rotational mechanics in patients with treated hypopituitarism. It was also aimed to find possible differences in these parameters according to the origin of hypopituitarism (congenital vs. acquired).Methods: The present prospective study involved 35 treated patients with hypopituitarism; however, 4 patients had to be excluded due to inferior image quality. The mean age of the remaining 31 cases was 56.3 ± 13.2 years (18 males). The control group consisted of 29 age- and sex-matched healthy volunteers (mean age: 55.3 ± 4.8 years, 14 males). In all cases a complete two-dimensional echocardiography examination was performed followed by three-dimensional speckle-tracking echocardiography.Results: No significant differences could be found in LV volumes between the controls and patients with hypopituitarism and hypopituitary subgroups. LV apical rotation (8.1 ± 5.1° vs. 10.6 ± 3.5°, p < 0.05) and LV twist (11.9 ± 5.3° vs. 15.1 ± 3.8°, p < 0.05) were impaired in the hypopituitary group with normally directed LV rotational mechanics as compared to the healthy controls. However, 13% of patients showed a near absence of LV twist called LV “rigid body rotation” (LV-RBR). There were no significant differences regarding LV apical and basal rotations and twist between acquired and congenital hypopituitary subgroups.Conclusions: Impaired LV apical rotation and twist could be demonstrated in hypopituitarism regardless of its origin. In the present study with small number of patients with hypopituitarism, LV-RBR was present in 13% of cases.

Isolation and culturing of cardiac fibroblasts (CF) induces rapid differentiation toward a myofibroblast phenotype, which is partly mediated by the high substrate stiffness of the culture plates. In the present study, a 3D model of Engineered Heart Matrix (EHM) of physiological stiffness (Youngs modulus ~15 kPa) was developed using primary adult rat CF and a natural hydrogel collagen type 1 matrix. CF were equally distributed, viable and quiescent for at least 13 days in EHM and the baseline gene expression of myofibroblast-markers alfa-smooth muscle actin (Acta2), and connective tissue growth factor (Ctgf) was significantly lower, compared to CF cultured in 2D monolayers. CF baseline gene expression of transforming growth factor-beta1 (Tgfβ1) and brain natriuretic peptide (Nppb) was higher in EHM-fibers compared to the monolayers. EHM stimulation by 10% cyclic stretch (1 Hz) increased the gene expression of Nppb (3.0-fold), Ctgf (2.1-fold) and Tgfβ1 (2.3-fold) after 24 h. Stimulation of EHM with TGFβ1 (1 ng/mL, 24 h) induced Tgfβ1 (1.6-fold) and Ctgf (1.6-fold). In conclusion, culturing CF in EHM of physiological stiffness reduced myofibroblast marker gene expression, while the CF response to stretch or TGFβ1 was maintained, indicating that our novel EHM structure provides a good physiological model to study CF function and myofibroblast differentiation.

Because of rising traumatic accidents and diseases, the number of patients suffering from nerve injury is increasing. Without effective rehabilitation therapy, the patients will get motor or sensory function losses or even a lifelong disability. As for amputees, neural interface technology can be used to splice nerves and electrical wires together in a way that allows them to control an artificial limb as if it was a natural extension of the body. However, the means the need for an autologous nerve to stimulate axonal regeneration and extension into target tissues, which are limited by the supply of donor nerves. Based on the principle of mechanical force regulating axon growth, in this paper, we developed a three-dimensional nerve stretch growth device for an implantable neural interface. The device consists of three motors controlled by single chip microcomputer and some mechanical parts. The stability and reliability of the device were tested. Then, we used neurons derived from human pluripotent stem cells by small chemical molecules to explore the optimal three-dimensional stretch culture parameters. Furthermore, we found that the axons were intact through 10 rotations per day and 1 mm of horizontal pulling per day. The results of this research will provide convenience for patients treated through an implantable neural interface.

The exploration of highly-active non-platinum electrocatalysts with low-cost has been regarded as a crucial way to alleviate the major bottleneck in electrocatalytic hydrogen evolution reaction (HER) technology. Herein, we demonstrate the bottom-up construction of three-dimensional (3D) hybrid architectures built from Ti 3 C 2 T x MXene and nitrogen-doped graphene nanosheets (MX/NG) through a facile and cost-effective co-assembly approach. The as-derived MX/NG architectures are endowed with a number of distinctive structural advantages, such as large specific surface areas, 3D cross-linked porous frameworks, ultrathin walls, optimized electronic structures, and good electron conductivity. As a result, exceptional HER performances with a relatively low onset potential, a small Tafel slope, and reliable long-term stability are achieved on the optimized MX/NG electrode, markedly outperforming those of bare Ti 3 C 2 T x and NG electrodes. The controllable construction of 3D hybrid architectures built from Ti 3 C 2 T x MXene and nitrogen-doped graphene nanosheets is achieved by a bottom-up co-assembly method. By virtue of the porous networks and optimized electronic structure, the resulting 3D architectures exhibit superior electrocatalytic properties toward hydrogen evolution reaction. [Display omitted] • The 3D MXene/N-doped graphene architectures are constructed by a bottom-up approach. • The 3D porous network provides accessible pores for the fast electrolyte transport. • The optimized electronic structure endows the hybrid with numerous active sites. • The resulting architectures show superior electrocatalytic ability towards HER. [ABSTRACT FROM AUTHOR]

In this paper, we concern with the haptotaxis system modeling oncolytic virotherapy. We present the global classical solution under appropriate regularity assumptions on the initial data. Our results generalize some well‐known results in the literature. [ABSTRACT FROM AUTHOR]

With the rapid digitalization and technological advancements of the modern society, the seriously increasing electromagnetic pollution has created stronger demand for advanced electromagnetic wave shielding and absorbing materials in both civilian and military fields. Multifunctional materials with ultra-lightweight, wide bandwidth, highly flexible and robustness are the future development direction to meet the applications. Graphene and MXene, as two typical 2D nanomaterials, have attracted considerable interests for the electromagnetic wave shielding and absorbing materials. More importantly, three dimensional (3D) cross-linked graphene or/and MXene based materials, where graphene or/and MXene sheets are interconnected into a macroscopic monolithic bulk material, can achieve excellent electromagnetic interference (EMI) shielding and microwave absorption (MA) performance, together with lightweight, exceptional mechanical properties and so on. This review addresses the construction methods of graphene and MXene based 3D cross-linked materials, and the effects of different fabrication methods toward the structure and EMI shielding and/or MA properties are discussed. Additionally, some perceptions and discussions are proposed for the future studies. In this Review Article, 3DGraphene, 3DMXene and 3DGraphene/MXene hybrid structures containing 3D cross-linked networks of graphene or/and MXene sheets as the building units are reviewed for their EMI shielding and microwave absorption. The recent development, including their construction methods and the effects of different fabrication methods for these three kinds of 3D cross-linked materials toward their structures and EMI shielding or/and MA performance are summarized. Future outlook of such 3D cross-linked materials and their associated challenges in electromagnetic interference shielding and microwave absorption field are also proposed and discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

Drought events occur more frequently against global warming in recent years. There is a great threat to the regional water resource management, ecosystem, and sustainable socio-economic development in China. Identification of drought events is essential to further understand characteristics of drought onset, evolution, and recovery. In this study, taking the Yangtze River Basin (YRB) as the study area, a new recognition method was proposed to identify the regional drought events using three-dimensional graph connectedness. By contrast, the specific procedure was first to identify the drought patches in each month using the threshold of occurring areas, and then to merge the drought patches in adjacent months using the threshold of overlapping areas, particularly in the conventional identification of drought events, such as clustering. This new identification was first to recognize the three-dimensional continuum with no limitation, and then to split the continuum using the threshold of occurring and overlapping areas, finally to extract the drought events with three-dimensional characteristics. The number of times was reduced significantly to calculate the overlaid area in space. The spatial-temporal patterns of droughts were obtained to verify the efficiency using the three-month YRB Standardized Precipitation Evapotranspiration Index (SPEI3) from 1960-2015. The results showed that: 1) 1.5% of the study region was considered as the threshold of occurring and overlapping areas, compared with the previous official reports. The drought events identified by the new method in YRB matched very well with the historical occurred ones, covering the onset, termination, and propagation. There was a significant positive correlation between the drought intensity of single drought events and the moisture deficit of surface soil in the affected region. The moisture deficit of surface soil was larger, as the drought intensity increased. It proved the efficiency of the new method in identifying and extracting three-dimensional drought events; 2) 281 drought events are identified in YRB from 1960-2015 and the drought duration of 64 events are larger than 4 months; 3) The duration of long duration drought events (which duration is larger than 4 months) decreased, while the drought area and drought frequency increased. Long duration droughts occurred 43 times during 1960-1999, the average drought duration and drought area were 8.1 months and 2.74×104 km², respectively. And long duration droughts occurred 21 times during 2000-2015, the average drought duration and drought area were 7.6 months and 3.50×104 km² respectively. The frequency of long duration drought events in the middle region of YRB is higher than that in the eastern and western regions. 4) The drought events occurred more frequently in Shannxi, Hubei, and Sichuan provinces, while the north Yunnan and Guizhou provinces presented a relatively lower frequency. Accumulative drought intensity was large in north Guizhou, northwest and east Sichuan, and Hubei provinces and Chongqing City, whereas, relatively small in the north Yunnan, Jiangxi and south Jiangsu provinces. The frequency and severity of drought events presented an increasing trend in the middle region of YRB, while a decreasing trend in the western and the eastern. The center of about 50% drought events moved to the northwest, due mainly to the water vapor transference and the migration of precipitation belt. The identification of drought events can effectively recognize and extract drought events in three-dimension images. The finding can provide greatly promising guidance for drought and regional water resource management. [ABSTRACT FROM AUTHOR]

Cell culturing is a cornerstone of tissue engineering, playing a crucial role in tissue regeneration, drug screening, and the study of disease mechanisms. Among various culturing techniques, 3D culture systems, particularly those utilizing suspended fiber scaffolds, offer a more physiologically relevant environment than traditional 2D monolayer cultures. These 3D scaffolds enhance cell growth, differentiation, and proliferation by mimicking the in vivo cellular milieu. This review focuses on the critical role of suspended fiber scaffolds in tissue engineering. We compare the effectiveness of 3D suspended fiber scaffolds with 2D culture systems, discussing their respective benefits and limitations in the context of tissue regeneration. Furthermore, we explore the preparation methods of suspended fiber scaffolds and their potential applications. The review concludes by considering future research directions for optimizing suspended fiber scaffolds to address specific challenges in tissue regeneration, underscoring their significant promise in advancing tissue engineering and regenerative medicine. [ABSTRACT FROM AUTHOR]

Obstructive sleep apnea (OSA) is accompanied by cognitive, motor, autonomic, learning, and affective abnormalities. The putamen serves several of these functions, especially motor and autonomic behaviors, but whether global and specific sub-regions of that structure are damaged is unclear. We assessed global and regional putamen volumes in 43 recently-diagnosed, treatment-naïve OSA (age, 46.4 ± 8.8 years; 31 male) and 61 control subjects (47.6 ± 8.8 years; 39 male) using high-resolution T1-weighted images collected with a 3.0-Tesla MRI scanner. Global putamen volumes were calculated, and group differences evaluated with independent samples t-tests, as well as with analysis of covariance (covariates; age, gender, and total intracranial volume). Regional differences between groups were visualized with 3D surface morphometry-based group ratio maps. OSA subjects showed significantly higher global putamen volumes, relative to controls. Regional analyses showed putamen areas with increased and decreased tissue volumes in OSA relative to control subjects, including increases in caudal, mid-dorsal, mid-ventral portions, and ventral regions, while areas with decreased volumes appeared in rostral, mid-dorsal, medial-caudal, and mid-ventral sites. Global putamen volumes were significantly higher in the OSA subjects, but local sites showed both higher and lower volumes. The appearance of localized volume alterations points to differential hypoxic or perfusion action on glia and other tissues within the structure, and may reflect a stage in progression of injury in these newly-diagnosed patients toward the overall volume loss found in patients with chronic OSA. The regional changes may underlie some of the specific deficits in motor, autonomic, and neuropsychologic functions in OSA.

Objects: To investigate the value of CT-based 3D templating software for pre-operative planning in patients with acetabular dysplasia undergoing total hip arthroplasty (THA) with a minimum follow-up of 2 years. Methods: We performed a retrospective review of a single surgeon’s cohort of patients with Crowe I to III developmental dysplastic hip (49 hips in 41 patients) who underwent cementless primary THA and were available for follow-up at a mean of 2.7 years after THA. We analyzed the accuracy of cup size prediction, the reliability of pre- and post-operative cup orientation and position of reconstructed rotation center using CT-based 3D templating software. Post-operative Harris Hip Score and lower limb discrepancy was obtained at the last follow-up. Results: The sizes of 71% of the cup components (35/49) were estimated exactly, and 100% of the cup size estimates were accurate to within one-cup size. There was good reproducibility of pre- and post-operative position of reconstructed rotation center (correlation coefficient r = 0.396 for vertical position, p = 0.005; r = 0.326 for horizontal position, p = 0.024). There was no substantial agreement between the planned acetabular orientation and that measured post-operatively (correlation coefficient –0.174 for inclination and 0.045 for anteversion). There were 44 (90%) excellent or good results according to HHS. Seven patients (14%) reported lower limb discrepancy. Conclusions: Pre-operative CT-based 3D templating made it possible to predict accurate cup size and achieve reproducible cup position in patients with dysplastic acetabulum. The reproducibility of cup orientation could not be demonstrated in this study.

Purpose: Report of a successful case of endovascular recanalization of an occluded superficial femoral artery (SFA) using Fiber Optic RealShape (FORS) technology. Case Report: A 79-year-old male was referred for evaluation of multiple ischemic pretibial ulcers of the right lower extremity. Computed tomography–angiography (CTA) imaging confirmed significant stenosis of the right common femoral artery (CFA) and an occlusion of the SFA from its origin to the Hunter’s canal. The patient was treated with a hybrid surgical procedure: an endarterectomy of the CFA and SFA origin was performed combined with an endovascular recanalization of the occluded SFA using FORS technology. During recanalization, the FORS guidewire slowly twisted subintimally around the occluded lumen of the SFA, maintaining the created corkscrew shape after pre-dilation with the percutaneous transluminal angioplasty (PTA) balloon and subsequent stenting. Conclusions: FORS technology can be successfully used during recanalization of an occluded SFA without the use of fluoroscopy. The corkscrew shape formed during recanalization in this case was retained during PTA balloon pre-dilation and stenting; this potentially improves hemodynamics and thereby reduces the risk of in-stent restenosis. However, expanding patient series and longer follow-up data are needed to increase the understanding of the feasibility and effectiveness of using FORS in the treatment of peripheral arterial occlusive disease.

Osteoarthritis (OA) is among the top 10 burdensome diseases, with the knee the most affected joint. Magnetic resonance imaging (MRI) allows whole-knee assessment, making it ideally suited for imaging OA, considered a multitissue disease. Three-dimensional (3D) MRI enables the comprehensive assessment of OA, including quantitative morphometry of various joint tissues. Manual tissue segmentation on 3D MRI is challenging but may be overcome by advanced automated image analysis methods including artificial intelligence (AI). This review presents examples of the utility of 3D MRI for knee OA, focusing on the articular cartilage, bone, meniscus, synovium, and infrapatellar fat pad, and it highlights several applications of AI that facilitate segmentation, lesion detection, and disease classification. [ABSTRACT FROM AUTHOR]

Fruit trees are important agricultural and forestry plants; their life is a complex system. Digital technology can help humans effectively perceive and recognize the life, production, and ecosystem of fruit trees, and then realize intelligent production. Nowadays, reducing the planting cost of fruit trees, improving the quality of fruit products, and promoting the marketing of fruit products, digital technology has increasingly become a hot research topic of fruit tree planting, and it is also an urgent need for the development of fruit industry. In this review, firstly, the concept and connotation of digital fruit tree were discussed systematically under the category of digital plant technology, its concept was defined as a theoretical technology and technical service platform system that comprehensively uses digital technology to study life, production, and ecosystem of fruit trees through high-throughput information acquisition and intelligent processing, and to realize the quantification, visual perception, and cognition of complex system of fruit trees. Secondly, the framework of the digital fruit tree technology system was put forward, its main modules included the classification of digital elements, digital data acquisition, construction of the digital cognitive model, and digital application services, then, the hierarchical structure of the technical framework was described in detail. Thirdly, the research progress of key technologies of digital fruit trees were systematically reviewed, including five aspects: 1) the fruit tree phenotype information acquisition technologies; 2) the fruit tree growth environment data acquisition technologies; 3) the fruit tree three-dimensional model construction and visualization technology; 4) the fruit tree digital breeding technologies; 5) the fruit big data and virtual reality technology. At the same time, the current development progress and technical bottlenecks of various key technologies were reviewed. Among them, the phenotypic technology runs through the lifeline of digital fruit trees, which is the key link in the construction of a digital fruit tree technology system. Under different scales of the sky, air, and earth, therefore, the performance characteristics, the phenotype platform flux, the accuracy and efficiency of phenotype acquisition sensors were summarized in this review. Indeed, phenotypic information acquisition and analysis technology are still one of the bottlenecks. Digital fruit tree technology has been widely used in many links of fruit production. So, fourthly, the effects and challenges were reviewed and discussed in detail from the perspective of fruit industry application. At present, the main application scenarios of digital fruit technology include tree shape management, growth monitoring, planting management, digital agricultural technology training, digital brand building, agricultural tourism digital service, and so on. Typical application cases were classified and introduced to provide application ideas for researchers and fruit production management personnel. Fifthly, the development trend, research hotspots, and technical breakthrough direction of digital fruit trees prospected, including big data technology, artificial intelligence technology, multi reconfiguration technology, virtual reality technology, and so on. To improve the intelligence level for the digital fruit tree technology system, the different technologies should be integrated deeply. This review could provide a useful reference for the further development of the digital fruit trees, for knowing the research hot spot, and for understanding the application bottleneck. [ABSTRACT FROM AUTHOR]

Background: The fit of implant‐supported prostheses is of prime importance for the long‐term success of implant therapy. Purpose This systematic review aimed to evaluate recent evidence on current techniques for assessing implant‐framework misfit, its associated strain/stress, and whether these misfits are related to mechanical, biological, and clinical consequences. Materials and methods: An electronic search for publications from January 2010 to October 2020 was performed using the Pubmed, Embase, Web of Science, and Cochrane Library databases with combined keywords on implant‐framework misfit assessments and related clinical complications. Inclusion and exclusion criteria were applied. After full‐text analyses, data extraction was implemented on current techniques of misfit assessment and the relationship between the misfit and the induced strain/stress. Results: A total of 3 in vivo and 92 in vitro studies were selected, including 47 studies on quantifying the degree of implant‐framework misfit with dimensional techniques, 24 studies measuring misfit‐induced strain/stress with modeling techniques, and 24 studies using both methods. The technical details, advantages, and limitations of each technique were illustrated. The correlation between the implant‐framework misfit and the induced strain/stress has been revealed in vitro, while that with the biological complications and implant/prostheses failure was weak in clinical studies. Conclusions: Dimensional and modeling techniques are available to measure the implant‐framework misfit. The passivity of implant‐supported fixed prostheses appeared related to the induced strain/stress, but not the clinical complications. Further studies combining three‐dimensional (3D) assessments using dimensional and modeling techniques was needed. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to depict the signal intensity pattern of the normal oculomotor nerve demonstrated on contrast-enhanced three-dimensional fluid-attenuated inversion recovery images. Materials and methods: Eighty-one patients were included in the study. Contrast-enhanced three-dimensional fluid-attenuated inversion recovery images with magnetisation-prepared rapid acquisition were reconstructed and evaluated in the coronal plane. The signal intensity of the cisternal segment of the oculomotor nerve was graded into a visual scale of 1 to 5 as compared to the white matter, grey matter and the pituitary stalk. The signal intensity ratio of the oculomotor nerve was consequently measured. Results: By using the visual scale, more than half of the oculomotor nerves showed higher signal intensity than the grey matter signal on contrast-enhanced three-dimensional fluid-attenuated inversion recovery images (59.3–80.2%). It can demonstrate a signal intensity similar to the pituitary stalk (14.8%) by visualisation. None of them showed signal intensity equal to the normal white matter signal. By signal intensity measurement, the mean signal intensity ratio of oculomotor nerves to white matter equals 1.54±0.20 (95% confidence interval (CI) 1.51–1.57); mean signal intensity ratio to grey matter equals 1.16±0.15 (95% CI 1.14–1.18); mean signal intensity ratio to the pituitary stalk equals 0.68±0.10 (95% CI 0.64–0.70). Conclusions: The normal oculomotor nerve visualised on contrast-enhanced three-dimensional fluid-attenuated inversion recovery images has a higher signal intensity than the white matter and may have a signal intensity similar to the grey matter or the pituitary stalk. The high signal intensity of the oculomotor nerve in contrast-enhanced three-dimensional fluid-attenuated inversion recovery should not be misinterpreted as a pathology. [ABSTRACT FROM AUTHOR]

Superselective intraarterial infusion chemoradiotherapy is a modality of oral cancer therapy in which the artery feeding the tumor is catheterized. 3D information about the carotid artery is required to enable the surgeon to judge whether to advance, retract, or rotate the catheter. For this purpose, we proposed and conducted a model experiment to assess a new method of catheterization that applies a tracking system using registration with a monocular camera using the maxillary arch as the anatomical landmark. In this method, the preoperative 3D computer tomography angiographic image of the carotid artery that the catheter will be passed through is overlaid on the 2D video image. The mean TRE was 0.96 ± 0.36 mm and 0.88 ± 0.31 mm and 1.12 ± 0.46 mm when images were registered with the anterior and posterior teeth as the landmarks, respectively; the difference was not significant (p = 0.21). This tracking system that enables markerless registration simply by taking images of the maxillary anterior teeth with a single camera was convenient and effective for catheterization. In this study, we propose the new application of this tracking system and a novel method of catheterization for superselective intraarterial infusion chemoradiotherapy for oral cancer. [ABSTRACT FROM AUTHOR]

Magnetic resonance fingerprinting (MRF) is highly promising as a quantitative MRI technique due to its accuracy, robustness, and efficiency. Previous studies have found high repeatability and reproducibility of 2D MRF acquisitions in the brain. Here, we have extended our investigations to 3D MRF acquisitions covering the whole brain using spiral projection k-space trajectories.Our travelling head study acquired test/retest data from the brains of 12 healthy volunteers and 8 MRI systems (3 systems at 3 T and 5 at 1.5 T, all from a single vendor), using a study design not requiring all subjects to be scanned at all sites. The pulse sequence and reconstruction algorithm were the same for all acquisitions.After registration of the MRF-derived PD T1 and T2 maps to an anatomical atlas, coefficients of variation (CVs) were computed to assess test/retest repeatability and inter-site reproducibility in each voxel, while a General Linear Model (GLM) was used to determine the voxel-wise variability between all confounders, which included test/retest, subject, field strength and site.Our analysis demonstrated a high repeatability (CVs 0.7–1.3% for T1, 2.0–7.8% for T2, 1.4–2.5% for normalized PD) and reproducibility (CVs of 2.0–5.8% for T1, 7.4–10.2% for T2, 5.2–9.2% for normalized PD) in gray and white matter.Both repeatability and reproducibility improved when compared to similar experiments using 2D acquisitions. Three-dimensional MRF obtains highly repeatable and reproducible estimations of T1 and T2, supporting the translation of MRF-based fast quantitative imaging into clinical applications.

This paper proposes a three–dimensional (3D) local boundary element model based on meshless moving least squares (MLS) method for ultrasonic wave propagation fractional order boundary value problems of functionally graded anisotropic (FGA) fiber-reinforced plates. The problem domain is split into several circular sub-domains. The nodal points are randomly distributed across the examined region. Each node is the focal point of a circular sub-domain that encircles it. The Laplace-transform approach is used to solve dynamic issues. In the local weak form of the governing equations for the converted quantities, a unit test function is utilized. The Gauss divergence theorem to the weak-form is used to produce local boundary-domain integral equations. A meshless approximation is achieved using the MLS method. To find time-dependent solutions, an inverse Laplace-transform approach is used. The effects of the fractional order parameter, functionally graded material, anisotropy, and the time characteristic of the laser pulse are investigated. The proposed method’s validity and performance are demonstrated for a two-dimensional problem with excellent agreement with the finite element method.

Background: Mandibular deficiency leading to facial asymmetry causes cosmetic deformity as well as psychological stigma for the patient. Correction of these mandibular asymmetries is a major challenge. The study investigates the efficacy of bidirectional mandible distraction for the treatment of mandibular deficiency. Methods: This prospective study included six individuals aged between 17 and 24.4 years. Five patients had hemifacial microsomia and one had unilateral temporomandibular joint ankyloses. All patients underwent mandibular distraction osteogenesis. Postoperative skeletal changes in affected mandible, and changes in occlusal plane and oral commissure cant were evaluated using three-dimensional reconstruction. Patient satisfaction and understanding of the procedure were assessed through three questionnaires administered during pre-distraction, distraction and postdistraction phases. Results: In pre-distraction phase, aesthetic appearance seemed to be the primary indication for surgery. In distraction phase, pain while chewing was the primary handicap. In post-distraction phase all patients were satisfied with the aesthetic outcome. The facial deformity was improved through mandibular distraction osteogenesis. On the affected side in all the patients, height and length of the mandible increased. Canting of the occlusal plane and oral commissure was corrected. Conclusion: Bidirectional mandible distraction is an effective treatment for correction of mandible deformities in adult patients. [ABSTRACT FROM AUTHOR]

Endovascular procedures are conventionally conducted using two dimensional fluoroscopy. A new technology platform, Fiber Optic RealShape (FORS), has recently been introduced allowing real time, three dimensional visualisation of endovascular devices using fiberoptic technology. It functions as an add on to conventional fluoroscopy and may facilitate endovascular procedures. This first in human study assessed the feasibility of FORS in clinical practice. A prospective cohort feasibility study was performed between July and December 2018. Patients undergoing (regular or complex) endovascular aortic repair (EVAR) or endovascular peripheral lesion repair (EVPLR) were recruited. FORS guidance was used exclusively during navigational tasks such as target vessel catheterisation or crossing of stenotic lesions. Three types of FORS enabled devices were available: a flexible guidewire, a Cobra-2 catheter, and a Berenstein catheter. Devices were chosen at the physician's discretion and could comprise any combination of FORS and non-FORS devices. The primary study endpoint was technical success of the navigational tasks using FORS enabled devices. Secondary study endpoints were user experience and fluoroscopy time. The study enrolled 22 patients: 14 EVAR and eight EVPLR patients. Owing to a technical issue during start up, the FORS system could not be used in one EVAR. The remaining 21 procedures proceeded without device or technology related complications and involved 66 navigational tasks. In 60 tasks (90.9%), technical success was achieved using at least one FORS enabled device. Users rated FORS based image guidance "better than standard guidance" in 16 of 21 and "equal to standard guidance" in five of 21 procedures. Fluoroscopy time ranged from 0.0 to 52.2 min. Several tasks were completed without or with only minimal X-ray use. Real time navigation using FORS technology is safe and feasible in abdominal and peripheral endovascular procedures. FORS has the potential to improve intra-operative image guidance. Comparative studies are needed to assess these benefits and potential radiation reduction. [ABSTRACT FROM AUTHOR]

Objective: To compare the short-term outcomes of three dimensional (3D) versus two dimensional (2D) laparoscopic procedures used for cholecystectomy. Methods: This study was conducted at minimally invasive surgery center of Liaquat University of Medical Health and Sciences (LUMHS) Jamshoro Pakistan, between 15th May 2017 to 16th December 2017 after taking informed consent. All patients were diagnosed cases of cholelithiasis without any complications. Patients having risk factors for inability to get access to gall bladder via laparoscope and in whom the chances of conversion to open cholecystectomy were greater were not included as part of study. One group of patients underwent cholecystectomy under 3D laparoscopy while other group underwent 2D laparoscopy. Surgeons included in the study were all well-trained. The short-term outcome noted were intraoperative and postoperative complications, conversion to open, operative time, mortality and hospital stay. Visual strain and headache for the surgeon in three D laparoscopic cholecystectomy. Results: A total of one hundred forty patients were included in the study. Group-A consists of sixty two females and eleven males whereas Group-B comprised of fifty eight females and fifteen males. Eight percent of patients in Group-A whereas in Group-B two percent had gallbladder rupture. Fifteen percent of patients in Group-A whereas 5.4% from Group-B had bleeding from liver bed. One patient from Group-A had CBD (Common Bile Duct) injury. Post-operatively two (2.73%) patients from Group-A had port site bleeding. Six (8.21%) patients had port site infection in Group-A. Conclusion: Three dimensional was found to have low incidence of intra-operative and post-operative complications compared to 2D laparoscopic cholecystectomy. [ABSTRACT FROM AUTHOR]

Introduction: The benefit of three-dimensional (3D) visualization for liver disease is uncertain. Aim: To evaluate the effectiveness and safety of 3D versus two-dimensional (2D) video-assisted hepatectomy for LD. Material and methods: We searched PubMed, Embase, Cochrane Library, Medline, and Web of Science for studies addressing 3D versus 2D for 2D until 30 February 2020. Study-specific effect sizes and their 95% confidence intervals (CIs) were combined to calculate the pooled value using a fixed-effects or random-effects model. Results: Nine studies with 808 patients were included. The 3D group had shorter operative time (mean difference (MD) = 34.39; 95% CI = 59.50, 9.28), experienced less intraoperative blood loss (MD = 106.55; 95% CI = 183.76, 29.34), and a smaller blood transfusion volume (MD = 88.25; 95% CI = 141.26, 35.24). The 3D group had a smaller difference between the predicted volume and the actual resected volume (MD = 103.25; 95% CI = 173.24, 33.26) and a lower rate of postoperative complications (odds ratio (OR) = 0.57; 95% CI: 0.35, 0.91). Conclusions: During surgery, 3D video-assisted hepatectomy could effectively reduce operative time, intraoperative bleeding, and blood transfusion volume, and had a smaller difference between the predicted volume and the actual resected volume and a lower rate of postoperative complications. More high-quality randomized controlled trials are required to verify the reliability and validity of our conclusion. [ABSTRACT FROM AUTHOR]