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Purpose: To develop and validate a highly efficient motion compensated free‐breathing isotropic resolution 3D whole‐heart joint T1/T2 mapping sequence with anatomical water/fat imaging at 0.55 T. Methods: The proposed sequence takes advantage of shorter T1 at 0.55 T to acquire three interleaved water/fat volumes with inversion‐recovery preparation, no preparation, and T2 preparation, respectively. Image navigators were used to facilitate nonrigid motion‐compensated image reconstruction. T1 and T2 maps were jointly calculated by a dictionary matching method. Validations were performed with simulation, phantom, and in vivo experiments on 10 healthy volunteers and 1 patient. The performance of the proposed sequence was compared with conventional 2D mapping sequences including modified Look‐Locker inversion recovery and T2‐prepared balanced steady‐SSFP sequence. Results: The proposed sequence has a good T1 and T2 encoding sensitivity in simulation, and excellent agreement with spin‐echo reference T1 and T2 values was observed in a standardized T1/T2 phantom (R2 = 0.99). In vivo experiments provided good‐quality co‐registered 3D whole‐heart T1 and T2 maps with 2‐mm isotropic resolution in a short scan time of about 7 min. For healthy volunteers, left‐ventricle T1 mean and SD measured by the proposed sequence were both comparable with those of modified Look‐Locker inversion recovery (640 ± 35 vs. 630 ± 25 ms [p = 0.44] and 49.9 ± 9.3 vs. 54.4 ± 20.5 ms [p = 0.42]), whereas left‐ventricle T2 mean and SD measured by the proposed sequence were both slightly lower than those of T2‐prepared balanced SSFP (53.8 ± 5.5 vs. 58.6 ± 3.3 ms [p < 0.01] and 5.2 ± 0.9 vs. 6.1 ± 0.8 ms [p = 0.03]). Myocardial T1 and T2 in the patient measured by the proposed sequence were in good agreement with conventional 2D sequences and late gadolinium enhancement. Conclusion: The proposed sequence simultaneously acquires 3D whole‐heart T1 and T2 mapping with anatomical water/fat imaging at 0.55 T in a fast and efficient 7‐min scan. Further investigation in patients with cardiovascular disease is now warranted. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Three‐dimensional (3D) histology analyses are essential to overcome sampling variability and understand pathological differences beyond the dissection axis. We present Path2MR, the first pipeline allowing 3D reconstruction of sparse human histology without a magnetic resonance imaging (MRI) reference. We implemented Path2MR with post‐mortem hippocampal sections to explore pathology gradients in Alzheimer's disease. METHODS: Blockface photographs of brain hemisphere slices are used for 3D reconstruction, from which an MRI‐like image is generated using machine learning. Histology sections are aligned to the reconstructed hemisphere and subsequently to an atlas in standard space. RESULTS: Path2MR successfully registered histological sections to their anatomic position along the hippocampal longitudinal axis. Combined with histopathology quantification, we found an expected peak of tau pathology at the anterior end of the hippocampus, whereas amyloid‐beta (Aβ) displayed a quadratic anterior‐posterior distribution. CONCLUSION: Path2MR, which enables 3D histology using any brain bank data set, revealed significant differences along the hippocampus between tau and Aβ. Highlights: Path2MR enables three‐dimensional (3D) brain reconstruction from blockface dissection photographs.This pipeline does not require dense specimen sampling or a subject‐specific magnetic resonance (MR) image.Anatomically consistent mapping of hippocampal sections was obtained with Path2MR.Our analyses revealed an anterior‐posterior gradient of hippocampal tau pathology.In contrast, the peak of amyloid‐beta (Aβ) deposition was closer to the hippocampal body. [ABSTRACT FROM AUTHOR]

The management of missing teeth as a result of dental trauma or associated with hypodontia in children and adolescents presents as a clinical challenge for the dental team. One of the options that is regaining popularity is dental autotransplantation. To improve autotransplantation outcomes, careful interdisciplinary planning, surgical simulation using cone beam computed tomography images and three‐dimensional‐printed teeth replicas should be undertaken for presurgical preparation. This case report showcases two applications of autotransplantation, with emphasis on interdisciplinary management, presurgical preparation and postsurgical orthodontic and aesthetic management to deliver a good long‐term, sustainable, biological outcome, as a part of a comprehensive rehabilitation treatment plan in children. [ABSTRACT FROM AUTHOR]

Objectives: The operative microscope (OM) has revolutionized the field of modern spine surgery, however, it remains limited by several drawbacks. Recently, the exoscope (EX) system has been designed to assistant spine surgery. It provides a three‐dimensional (3D) high‐definition (HD) operative experience and becomes an alternative to the OM. The aim of the study was to evaluate the clinical outcomes, advantages and limitations of EX‐assisted minimally invasive transforaminal lumbar interbody fusion (EMIS‐TLIF) and OM‐assisted MIS‐TLIF (OMIS‐TLIF). Methods: The clinical outcomes were assessed in 47 patients with lumbar degenerative diseases (LDD) who underwent MIS‐TLIF assisted with the OM or EX between January 2019 and September 2020. A total of 22 were treated with EMIS‐TLIF, and 25 received OMIS‐TLIF. Perioperative parameters (including sex, age, number of fusion levels and body mass index), perioperative parameters (operation time, intraoperative blood loss, postoperative drainage, postoperative hospitalization stay, and duration of follow‐up), visual analogue scale (VAS) of back pain, VAS of leg pain, Oswestry disability index (ODI) scores and clinical outcomes were assessed and compared. Image quality, handling of equipment, ergonomics, 3D glasses and educational usefulness were scored according to a questionnaire. Results: Operation time in the OMIS‐TLIF group (121.92 ± 16.92 min) was significantly increased compared with that in the EMIS‐TLIF group (111.00 ± 19.87 min) (P < 0.05). The VAS of the back pain and ODI scores in the EMIS‐TLIF group were significantly lower compared with the OMIS‐TLIF group at 1 week postoperatively (P < 0.05). The good‐excellent outcomes rate was 90.91% in the EMIS‐TLIF group and 88.00% in the OMIS‐TLIF group, and there was no significant difference. A total of 44 visits completed the questionnaire. The results of the questionnaire showed that the EX has exhibited advantages regarding handing of equipment, ergonomics and educational usefulness, and comparable image quality as compared with the OM, however, operating surgeons complained uncomfortable sensation when wearing 3D glasses. Conclusions: The EMIS‐TLIF was a safe and effective procedure in the management of LDD as compared with the OMIS‐LIF. Meanwhile, EMIS‐TLIF might resulted in a short operation time. [ABSTRACT FROM AUTHOR]

In this study, a three‐dimensional (3D) finite‐difference time‐domain (FDTD) approach utilizing time‐domain weighted Laguerre polynomials (WLPs) and space‐domain isotropic–dispersion (ID) finite‐difference scheme is presented (i.e., 3D ID‐WLP‐FDTD). The method exhibits unconditional stability and comprehensively improved performance such as lower anisotropic numerical dispersion error. To demonstrate its advantage, it is applied in an example of the propagation of a plane wave in a 3D cavity. The results calculated by the proposed ID‐WLP‐FDTD method and the conventional 3D WLP‐FDTD are compared, which shows that the proposed method can achieve reduced anisotropic numerical dispersion error while consuming less calculation time and hardware resources. [ABSTRACT FROM AUTHOR]

A polarization‐insensitive three‐dimensional (3‐D) microwave absorber is proposed in this letter for ultra‐wideband radar section cross (RCS) reduction. The lossy layer of the designed absorber is evolved from the bent metallic strip with a center‐embedded resistor, which performs the property of absorption‐reflection‐absorption due to its multimode resonances. A short stub with a center‐embedded resistor is connected to the long‐bent strip to abolish the reflection performance, for the sake of achieving wide absorption performance. The fundamental working principle of the designed structure is explained adequately using an intuitive equivalent circuit model. Additionally, the absorber is designed, fabricated, and measured for validation, whose fractional bandwidths is 151.5% with at least 10‐dB RCS reduction. [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]

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]

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]

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]

The effects of acute changes during hemodialysis (HD) on the myocardium are not yet known. The invention of three‐dimensional speckle tracking echocardiography (3DSTE) has offered clinicians a new method to assess the movements of ventricular segments simultaneously in three spatial directions. The aim of this study was to evaluate the effect of first weekly standard HD process on the left ventricle (LV) and right ventricle (RV) global and regional myocardial function in patients with normal left ventricle ejection fraction using 3DSTE‐derived indices. Patients (n=38) receiving maintenance HD in our clinic who have no known cardiovascular disease are examined just before and after a HD session using 3DSTE. Demographic and comorbidity data, renal replacement treatment characteristics, and laboratory test results are recorded. 3DSTE analysis is performed to calculate the LV global longitudinal, circumferential area and radial peak systolic strain, as well as RV septum and free‐wall longitudinal strain and fractional area change. Patients are aged 52.8 ± 13.6 years and 52.6% of them are male. Mean dialysis duration is 56 months. The LV strain values of the patients changed markedly before and after HD (GLS: −14.2 ± 5.2, −11.1 ± 4.6 [P <.001], GCS: −14.8 ± 4.2, −12.4 ± 5.28 [P <.009]; GRS: 41.5 ± 16, 33.3 ± 16.5 [P =.003]; AREA −24.7 ± 7.2, −20.1 ± 7.6 [P =.001], respectively). We could not demonstrate any improvement in RV strain values before or after HD. LV strain values are positively correlated with blood pressure variability during the dialysis sessions. LV function is preserved better after HD in patients on beta or calcium channel blocker therapy compared to those who do not use these agents (P <.001, P <.01, respectively). HD treatment results in deterioration in all LV strain directions but not in RV. Strain assessment may improve vascular risk stratification of patients on chronic HD. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: Augmented reality (AR) allows for the addition of transparent virtual images and video to one's view of a physical environment. Our objective was to develop a head‐worn, AR system for accurate, intraoperative localization of pathology and normal anatomic landmarks during open head and neck surgery. Study Design: Face validity and case study. Methods: A protocol was developed for the creation of three‐dimensional (3D) virtual models based on computed tomography scans. Using the HoloLens AR platform, a novel system of registration and tracking was developed. Accuracy was determined in relation to actual physical landmarks. A face validity study was then performed in which otolaryngologists were asked to evaluate the technology and perform a simulated surgical task using AR image guidance. A case study highlighting the potential usefulness of the technology is also presented. Results: An AR system was developed for intraoperative 3D visualization and localization. The average error in measurement of accuracy was 2.47 ± 0.46 millimeters (1.99, 3.30). The face validity study supports the potential of this system to improve safety and efficiency in open head and neck surgical procedures. Conclusions: An AR system for accurate localization of pathology and normal anatomic landmarks of the head and neck is feasible with current technology. A face validity study reveals the potential value of the system in intraoperative image guidance. This application of AR, among others in the field of otolaryngology–head and neck surgery, promises to improve surgical efficiency and patient safety in the operating room. Level of Evidence: 2b Laryngoscope, 129:S1–S11, 2019 [ABSTRACT FROM AUTHOR]

We propose a crosstalk‐free dual‐view integral imaging display. It is composed of a display panel, a barrier array, and a micro‐lens array. The central barrier is located at the vertical central axes of the display panel and the micro‐lens array to split the element image array and the viewing zone. Moreover, other barriers are located at the margins of the elemental images and corresponding micro‐lenses to eliminate the crosstalk. The lights emitting from the left and right half of the element image array are modulated by the left and right half of the micro‐lens array to reconstruct the right and left viewing zones, respectively. A prototype of the proposed dual‐view integral imaging display is developed, and good experimental results agree well with the theory. [ABSTRACT FROM AUTHOR]

Objectives: To test smile dimension variations in adult African American and Caucasian females and males.Setting and Sample Population: The University of Alabama at Birmingham School of Dentistry and Hospital. Three hundred and ninety-four participants were recruited; African American females and males distributed over five age groups: 20-30, 30-40, 40-50, 50-60 and older than 60.Material& Methods: Three-dimensional surface imaging was used to acquire two images of each participant, one at rest and one upon smile. Landmarks were plotted on the lips and linear distances measured to assess the length of the upper and lower lips, mouth width at rest and upon smile, gingival and dental display upon smile.Results: Linear dimensions are larger in males than in females, and in African Americans than in Caucasians, except for the length of the upper lip that does not differ between male African American and Caucasian males, in any given age group. Gingival display and dental display decrease with age in all groups.Conclusion: Norms should reflect race, age and sex in order to optimize treatment goals. [ABSTRACT FROM AUTHOR]

Large‐area crack‐free 2D and 3D WO3 inverse opal (IO) films, using a wide range of sizes of sacrificial PS spheres as colloidal crystal template, were fabricated by "dynamic hard template infiltration strategy". First a dynamic PS opal film was formed floating on the surface of water followed by infiltration of a preformed WO3 sol underneath the PS opal film. The resultant PS/WO3 opal composite film was then deposited on various types of substrates (rigid and flexible) and 2D WO3 IO films were obtained following the removal of the PS template by chemical method. Based on this strategy, multiple layer WO3 IOs were fabricated through a layer by layer route. The WO3 IO films deposited on indium tin oxide coated conductive (ITO) substrates were used as active electrode in the fabrication of electrochromic devices, demonstrating their advanced properties for electrochromic application. The "dynamic hard template infiltration" strategy is used to fabricate large‐area crack‐free 2D and 3D inverse opal (IO) films, deposited on various types of substrates, by using a wide range of sizes of sacrificial PS spheres as colloidal crystal template. Multiple layer WO3 IOs were further fabricated through a layer by layer route. These films were used as active electrode in electrochromic devices and showed increased optical density as the number of layers increased. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study is to evaluate intra‐ and interobserver agreement for measurement of intracranial, cerebellar, and thalamic volume with the Virtual Organ Computer‐aided AnaLysis (VOCAL) technique in three‐dimensional ultrasound images, in comparison to two‐dimensional measurements of these brain structures. Three‐dimensional ultrasound images of the brains of 80 fetuses at 20–24 weeks’ gestational age were obtained from YOUth, a Dutch prospective cohort study. Two observers performed offline measurement of the occipitofrontal diameter, intracranial volume, transcerebellar diameter, cerebellar volume, and thalamic width, area, and volume, independently. VOCAL was used for calculation of the volumes. The two‐way random, single measures intraclass correlation coefficient (ICC) was used for analysis of agreement and Bland–Altman plots were configured. Intra‐ and interobserver agreement was almost perfect for occipitofrontal diameter (intra ICC 0.88, 95% CI 0.82–0.92; inter ICC 0.91, 95% CI 0.85–0.94), intracranial volume (intra ICC 0.96, 95% CI 0.91–0.98; inter ICC 0.97, 95% CI 0.96–0.98) and transcerebellar diameter (intra ICC 0.91, 95% CI 0.86–0.94; inter ICC 0.86, 95% CI 0.78–0.910). For cerebellar volume, the intraobserver agreement was almost perfect (0.85, 95% CI 0.76–0.90), whereas the interobserver agreement was substantial (0.75, 95% CI 0.44–0.88). Agreement was only moderate for thalamic measurements. Bland–Altman plots for the volume measurements are normally distributed with acceptable mean differences and 95% limits of agreement. The intra‐ and interobserver agreement of the measurement of intracranial and cerebellar volume with VOCAL was almost perfect. These measurements are therefore reliable, and can be used to investigate fetal brain development. Thalamic measurements are not reliable enough. [ABSTRACT FROM AUTHOR]

Objectives: Craniofacial assessments often involve three-dimensional facial imaging using an expensive camera with 6 SLR lenses to analyse the positions and relations of anatomic landmarks. Recently, a 3D small-format, handheld camera was developed; however, the accuracy and reliability of this system are largely unknown. The purpose of this study was to evaluate the accuracy and reliability of this system.Materials& Methods: A total of 30 sets of evaluations were completed by 2 examiners on 5 human subjects, using 3 different methods: direct callipers, 3D handheld camera and conventional tripod 3D camera images. Each evaluation included 29 anthropometric landmarks that were used as reference points for facial analysis. Two examiners marked the landmarks directly on the faces and measured linear distances using the 3 measurement methods.Results: Accuracy analysis was performed for handheld vs direct calliper vs conventional camera measurements. Each of these analyses yielded a grand mean of correlation coefficients of .98. Bias measurements revealed that the handheld and conventional camera methods yielded larger measurements than direct callipers (with a mean difference of 1.74, 1.56 mm, respectively, for rater 1 and 0.94, 1.02 mm, respectively, for rater 2). When compared to one another, both the handheld camera and the conventional camera methods yielded similar values for most measurements, with the average overall difference between these modalities of 0.03 mm for rater 1 and 0.07 mm for rater 2.Conclusions: The 3D handheld camera showed high accuracy and reliability in comparison with traditional models, indicating that this system may provide a useful tool in craniofacial anthropometry. [ABSTRACT FROM AUTHOR]

Objective: To analyse fibroid vascularisation measured with three‐dimensional (3D) power Doppler in relation to absolute fibroid volume change during 12 months of follow up and in relation to fibroid growth rate per year. Design: A prospective cohort study was performed between March 2012 and March 2014. Setting: Outpatient clinic of the VU medical centre, Amsterdam. Population or sample: All premenopausal women diagnosed with a maximum of two fibroids with expectant management were consecutively included. Methods: Three‐dimensional ultrasound including power Doppler was performed at baseline, 3, 6 and 12 months. Volume and vascular parameters were calculated using VOCAL software. Main outcome measures: The relationship between vascular index (VI) at baseline and fibroid volume over time was analysed using linear mixed model analyses for repeated measurements. Second, the relationship between VI at baseline and fibroid growth rate per year was calculated using linear regression analyses. Analyses were adjusted for possible confounders. Results: In all, 66 women (mean age 42 years) completed 12 months of follow up without treatment. Baseline fibroid vascularisation (VI) measured with 3D power Doppler is correlated with fibroid volume at 12 months (P = 0.02 ). An increase of 1% in VI at baseline was associated with a 7.00‐cm3 larger fibroid volume at 12 months. Furthermore, vascularisation was also associated with fibroid growth rate per year (P = 0.04). Conclusion: In women with uterine fibroids without therapy, baseline vascularisation (VI) measured with 3D power Doppler is correlated with absolute fibroid volume change at 12 months and with fibroid growth rate per year. Tweetable abstract: Fibroid vascularisation correlates with absolute fibroid volume change and fibroid growth rate per year. [ABSTRACT FROM AUTHOR]

ABSTRACT A three-dimensional (3D) digital preoperative planning system for the osteosynthesis of distal radius fractures was developed for clinical practice. To assess the usefulness of the 3D planning for osteosynthesis, we evaluated the reproducibility of the reduction shapes and selected implants in the patients with distal radius fractures. Twenty wrists of 20 distal radius fracture patients who underwent osteosynthesis using volar locking plates were evaluated. The 3D preoperative planning was performed prior to each surgery. Four surgeons conducted the surgeries. The surgeons performed the reduction and the placement of the plate while comparing images between the preoperative plan and fluoroscopy. Preoperative planning and postoperative reductions were compared by measuring volar tilt and radial inclination of the 3D images. Intra-class correlation coefficients (ICCs) of the volar tilt and radial inclination were evaluated. For the implant choices, the ICCs for the screw lengths between the preoperative plan and the actual choices were evaluated. The ICCs were 0.644 ( p < 0.01) and 0.625 ( p < 0.01) for the volar tilt and radial inclination in the 3D measurements, respectively. The planned size of plate was used in all of the patients. The ICC for the screw length between preoperative planning and actual choice was 0.860 ( p < 0.01). Good reproducibility for the reduction shape and excellent reproducibility for the implant choices were achieved using 3D preoperative planning for distal radius fracture. Three-dimensional digital planning was useful to visualize the reduction process and choose a proper implant for distal radius fractures. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2646-2651, 2017. [ABSTRACT FROM AUTHOR]

Purpose To achieve rapid, high resolution whole-brain gray matter (GM) imaging by developing a novel, single-slab three-dimensional dual-echo fast-spin-echo pulse sequence and GM-selective reconstruction. Methods Unlike conventional GM imaging that uses time-consuming double-inversion-recovery preparation, the proposed pulse sequence was designed to have two split portions along the echo train, in which the first half was dedicated to yield short inversion recovery (IR)-induced white matter suppression and variable-flip-angle-induced two-step GM signal evolution while the second half cerebrospinal fluid-only signals. Multi-step variable-flip-angle schedules and sampling reordering were optimized to yield high GM signals while balancing cerebrospinal fluid signals between ECHOes. GM-selective images were then reconstructed directly from the weighted subtraction between ECHOes by solving a sparse signal recovery problem. In vivo studies were performed to validate the effectiveness of the proposed method over conventional double-inversion-recovery. Results The proposed method, while achieving one millimeter isotropic, whole-brain GM imaging within 5.5 min, showed superior performance than conventional double-inversion-recovery in producing GM-only images without apparent artifacts and noise. Conclusion We successfully demonstrated the feasibility of the proposed method in achieving whole-brain GM imaging in a clinically acceptable imaging time. The proposed method is expected to be a promising alternative to conventional double-inversion-recovery in clinical applications. Magn Reson Med 78:1691-1699, 2017. © 2017 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]

Purpose: To develop and assess a new technique for three-dimensional (3D) full lung T1 and T2* mapping using a single free breathing scan during a clinically feasible time.Materials and Methods: A 3D stack of dual-echo ultrashort echo time (UTE) radial acquisition interleaved with and without a WET (water suppression enhanced through T1 effects) saturation pulse was used to map T1 and T2* simultaneously in a single scan. Correction for modulation due to multiple views per segment was derived. Bloch simulations were performed to study saturation pulse excitation profile on lung tissue. Optimization of the saturation delay time (for T1 mapping) and echo time (for T2* mapping) was performed. Monte Carlo simulation was done to predict accuracy and precision of the sequence with signal-to-noise ratio of in vivo images used in the simulation. A phantom study was carried out using the 3D interleaved saturation recovery with dual echo ultrashort echo time imaging (ITSR-DUTE) sequence and reference standard inversion recovery spin echo sequence (IR-SE) to compare accuracy of the sequence. Nine healthy volunteers were imaged and mean (SD) of T1 and T2* in lung parenchyma at 3T were estimated through manually assisted segmentation. 3D lung coverage with a resolution of 2.5 × 2.5 × 6 mm3 was performed and nominal scan time was recorded for the scans. Repeatability was assessed in three of the volunteers. Regional differences in T1/T2* values were also assessed.Results: The phantom study showed accuracy of T1 values to be within 2.3% of values obtained from IR-SE. Mean T1 value in lung parenchyma was 1002 ± 82 ms while T2* was 0.85 ± 0.1 ms. Scan time was ∼10 min for volunteer scans. Mean coefficient of variation (CV) across slices was 0.057 and 0.09, respectively. Regional variation along the gravitational direction and between right and left lung were not significant (P = 0.25 and P = 0.06, respectively) for T1. T2* showed significant variation (P = 0.03) along the gravitational direction. Repeatability for three volunteers was within 0.7% for T1 and 1.9% for T2*.Conclusion: 3D T1 and T2* maps of the entire lung can be obtained in a single scan of ∼10 min with a resolution of 2.5 × 2.5 × 6 mm3 .Level Of Evidence: 2 J. Magn. Reson. Imaging 2017;45:1097-1104. [ABSTRACT FROM AUTHOR]

ABSTRACT Steel well casings in or near a hydrocarbon reservoir can be used as source electrodes in time-lapse monitoring using grounded line electromagnetic methods. A requisite component of carrying out such monitoring is the capability to numerically model the electromagnetic response of a set of source electrodes of finite length. We present a modelling algorithm using the finite-element method for calculating the electromagnetic response of a three-dimensional conductivity model excited using a vertical steel-cased borehole as a source. The method is based on a combination of the method of moments and the Coulomb-gauged primary-secondary potential formulation. Using the method of moments, we obtain the primary field in a half-space due to an energized vertical steel casing by dividing the casing into a set of segments, each assumed to carry a piecewise constant alternating current density. The primary field is then substituted into the primary-secondary potential finite-element formulation of the three-dimensional problem to obtain the secondary field. To validate the algorithm, we compare our numerical results with: (i) the analytical solution for an infinite length casing in a whole space, excited by a line source, and (ii) a three-layered Earth model without a casing. The agreement between the numerical and analytical solutions demonstrates the effectiveness of our algorithm. As an illustration, we also present the time-lapse electromagnetic response of a synthetic model representing a gas reservoir undergoing water flooding. [ABSTRACT FROM AUTHOR]

Many medical graduates are deficient in anatomy knowledge and perhaps below the standards for safe medical practice. Three-dimensional visualization technology (3DVT) has been advanced as a promising tool to enhance anatomy knowledge. The purpose of this review is to conduct a meta-analysis of the effectiveness of 3DVT in teaching and learning anatomy compared to all teaching methods. The primary outcomes were scores of anatomy knowledge tests expressed as factual or spatial knowledge percentage means. Secondary outcomes were perception scores of the learners. Thirty-six studies met the inclusion criteria including 28 (78%) randomized studies. Based on 2,226 participants including 2,128 from studies with comparison groups, 3DVTs (1) resulted in higher ( d = 0.30, 95%CI: 0.02-0.62) factual knowledge, (2) yielded significant better results ( d = 0.50, 95%CI: 0.20-0.80) in spatial knowledge acquisition, and (3) produced significant increase in user satisfaction ( d = 0.28, 95%CI = 0.12-0.44) and in learners' perception of the effectiveness of the learning tool ( d = 0.28, 95%CI = 0.14-0.43). The total mean scores (out of five) and ±SDs for QUESTS's Quality and Strength dimensions were 4.38 (±SD 1.3) and 3.3 (±SD 1.7), respectively. The results have high internal validity, for the improved outcomes of 3DVTs compared to other methods of anatomy teaching. Given that anatomy teaching and learning in the modern medical school appears to be approaching a crisis, 3DVT can be a potential solution to the problem of inadequate anatomy pedagogy. Anat Sci Educ 8: 525-538. © 2014 American Association of Anatomists. [ABSTRACT FROM AUTHOR]

Assembly of carbon nanomaterials into three-dimensional (3D) architectures is necessary to harness their unique physiochemical properties for tissue engineering and regenerative medicine applications. Herein, we report the fabrication and comprehensive cytocompatibility assessment of 3D chemically crosslinked macrosized (5-8 mm height and 4-6 mm diameter) porous carbon nanotube (CNT) scaffolds. Scaffolds prepared via radical initiated thermal crosslinking of single- or multiwalled CNTs (SWCNTs and MWCNTs) possess high porosity (>80%), and nano-, micro-, and macroscale interconnected pores. MC3T3 preosteoblast cells on MWCNT and SWCNT scaffolds showed good cell viability comparable to poly(lactic-co-glycolic) acid (PLGA) scaffolds after 5 days. Confocal live cell and immunofluorescence imaging showed that MC3T3 cells were metabolically active and could attach, proliferate, and infiltrate MWCNT and SWCNT scaffolds. SEM imaging corroborated cell attachment and spreading and suggested that cell morphology is governed by scaffold surface roughness. MC3T3 cells were elongated on scaffolds with high surface roughness (MWCNTs) and rounded on scaffolds with low surface roughness (SWCNTs). The surface roughness of scaffolds may be exploited to control cellular morphology and, in turn, govern cell fate. These results indicate that crosslinked MWCNTs and SWCNTs scaffolds are cytocompatible, and open avenues toward development of multifunctional all-carbon scaffolds for tissue engineering applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3212-3225, 2015. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective To evaluate the contribution of three-dimensional ( 3D) power Doppler angiography ( 3D-PDA) to the differential diagnosis of adnexal masses. Methods This was a prospective study in women diagnosed with a persistent adnexal mass and subsequently scheduled for surgery in a tertiary university hospital. All women were evaluated by transvaginal/transrectal ultrasound according to a predetermined three-step protocol, with transabdominal ultrasound being performed in some cases. First, morphological evaluation of the mass was performed using gray-scale 'pattern recognition' (first step). Lesions diagnosed as having a benign pattern were considered as being at low risk of malignancy whereas tumors with solid components, ascites and/or signs of carcinomatosis were considered as being at high risk of malignancy. In both cases no further test was performed and a decision regarding clinical management, either for follow-up or surgery, was taken. Tumors with solid components but without signs of ascites or carcinomatosis were considered as being at intermediate risk of malignancy. These lesions were assessed by two-dimensional ( 2D) PDA to evaluate tumor vascularity (color score) (second step). Solid tumors with a color score of 1 or 2 were considered as benign and no further test was performed, while tumors with a color score of 2, 3 or 4 within solid components or a color score of 3 or 4 in the case of a solid tumor were considered as malignant. The latter group underwent 3D-PDA assessment (third step). Vascularization index ( VI) was calculated in a 1-mL sphere of the most vascularized area of the tumor. When a VI ≥ 24.015% was found, the tumor was considered as malignant. All masses were removed surgically and definitive histological diagnosis was used as the gold standard. Sensitivity and specificity for each strategy were calculated and compared. In the case of bilateral tumors, only the more suspicious one was used for analysis. Results A total of 367 adnexal masses diagnosed in 367 women (mean age, 46.5 (range, 18-80) years) were evaluated during the study period. Of these, 86 masses were malignant and 281 were benign. The sensitivity and specificity for each assessment strategy were as follows: one-step, 97.7% and 78.6%; two-step, 94.2% and 97.9% ( P < 0.001 for specificity when compared with that of one-step); three-step, 90.7% and 98.9% (not statistically significant when compared with that of two-step). Conclusions The addition of 2D-PDA in the differential diagnosis of an adnexal mass significantly increases specificity while sensitivity remains high; however performing subsequent 3D-PDA does not provide additional information or further improve diagnostic performance subsequent to 2D-PDA. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Objectives To assess the feasibility of a novel percutaneous navigation system ( Translucent Medical, Inc., Santa Cruz, CA, USA) that integrates position-tracking technology with a movable tablet display. Materials and Methods A total of 18 fiducial markers, which served as the target centres for the virtual tumours (target fiducials), were implanted in the prostate and kidney of a fresh cadaver, and preoperative computed tomography ( CT) was performed to allow three-dimensional model reconstruction of the surgical regions, which were registered on the body intra-operatively. The position of the movable tablet's display could be selected to obtain the best recognition of the interior anatomy. The system was used to navigate the puncture needle (with position-tracking sensor attached) using a colour-coded, predictive puncture-line. When the operator punctured the target fiducial, another fiducial, serving as the centre of the ablative treatment (treatment fiducial), was placed. Postoperative CT was performed to assess the digitized distance (representing the real distance) between the target and treatment fiducials to evaluate the accuracy of the procedure. Results The movable tablet display, with position-tracking sensor attached, enabled the surgeon to visualize the three-dimensional anatomy of the internal organs with the help of an overlaid puncture line for the puncture needle, which also had a position-tracking sensor attached. The mean (virtual) distance from the needle tip to the target (calculated using the computer workstation), was 2.5 mm. In an analysis of each digitalized axial component, the errors were significantly greater along the z-axis ( P < 0.01), suggesting that the errors were caused by organ shift or deformation. Conclusion This virtual navigation system, integrating a position-tracking sensor with a movable tablet display, is a promising advancement for facilitating percutaneous interventions. The movable display over the patient shows a preoperative three-dimensional image that is aligned to the patient. Moving the display moves the image, creating the feeling of looking through a window into the patient, resulting in instant perception and a direct, intuitive connection between the physician and the anatomy. [ABSTRACT FROM AUTHOR]

The hyporheic zone is often a critical component of river systems. Hyporheic exchange is generally forced by variation in riverbed topography such as due to bed forms. Most previous research on bed form-driven hyporheic flow has focused on two-dimensional (2-D) dunes and ripples, while little has been done on their three-dimensional (3-D) counterparts. Here we compared hyporheic exchange and associated metrics for a previously studied pair of corresponding 2-D and 3-D bed forms. To accomplish this, a series of multiphysics computational fluid dynamics models were conducted both in 2-D and 3-D with similar open channel Reynolds numbers ( Re). Results show that the pressure gradient along the sediment-water interface is highly sensitive to the spatial structure of bed forms, which consequently determines hyporheic flow dynamics. Hyporheic flux is a function of Re for both 2-D and 3-D dunes via a power law; however, the equivalent 3-D dunes have a higher flux since the 3-D form induces more drag. The hyporheic zone depths and volumes are only slightly different with the 3-D case having a larger volume. The mean fluid residence times for both cases are related to Re by an inverse power law relationship, with the 3-D dune having smaller residence times at moderate to high Re. The effects of increasing flux on residence time in 3-D dunes are partly modulated by a slightly increasing hyporheic volume. Our results suggest that a 2-D idealization is a reasonable approximation for the more complex 3-D situation if local details are unimportant but that development of predictive models for mean fluxes and residence times, which are critical for biogeochemical processes, based on 2-D models may be insufficient. [ABSTRACT FROM AUTHOR]

Purpose: Understanding the three-dimensional (3D) morphology of the spinal cord microvasculature has been limited by the lack of an effective high-resolution imaging technique. In this study, synchrotron radiation microcomputed tomography (SRμCT), a novel imaging technique based on absorption imaging, was evaluated with regard to the detection of the 3D morphology of the rat spinal cord microvasculature. Methods: Ten Sprague-Dawley rats were used in this ex vivo study. After contrast agent perfusion, their spinal cords were isolated and scanned using conventional x-rays, conventional micro-CT (CμCT), and SRμCT. Results: Based on contrast agent perfusion, the microvasculature of the rat spinal cord was clearly visualized for the first time ex vivo in 3D by means of SRμCT scanning. Compared to conventional imaging techniques, SRμCT achieved higher resolution 3D vascular imaging, with the smallest vessel that could be distinguished approximately 7.4 μm in diameter. Additionally, a 3D pseudocolored image of the spinal cord microvasculature was generated in a single session of SRμCT imaging, which was conducive to detailed observation of the vessel morphology. Conclusions: The results of this study indicated that SRμCT scanning could provide higher resolution images of the vascular network of the spinal cord. This modality also has the potential to serve as a powerful imaging tool for the investigation of morphology changes in the 3D angioarchitecture of the neurovasculature in preclinical research. [ABSTRACT FROM AUTHOR]

MRI phase data often suffers from phase wrapping (i.e., phase may be discontinuous by 2π jumps). Numerous MRI phase unwrapping strategies were developed in the past using a criterion based on phase information of local or neighboring voxels. In this study, an alternative and novel three dimensional phase unwrapping strategy is introduced. This method considers the global character of the phase distribution and utilizes continuous trigonometric functions to construct an expected phase map as an unwrapping reference, which is then used to guide the phase correction of every individual voxel. The original phase is estimated by analyzing the derivative of the wrapped phase image. Simulations of various phase wrapped situations were performed and this new method was also used for an in vivo application (i.e., MRI automatic global shimming). Both simulated and experimental results demonstrate that our proposed method is more reliable and robust than traditional algorithms at obtaining correct phase maps, especially in regions of low-signal and air cavities, such as the abdomen and pelvis. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A preliminary clinical trial using state-of-the-art multiphoton tomography (MPT) and optical coherence tomography (OCT) for three-dimensional (3D) multimodal in vivo imaging of normal skin, nevi, scars and pathologic skin lesions has been conducted. MPT enabled visualization of sub-cellular details with axial and transverse resolutions of <2 μm and <0.5 μm, respectively, from a volume of 0.35 × 0.35 × 0.2 mm3 at a frame rate of 0.14 Hz (512 × 512 pixels). State-of-the-art OCT, operating at a center wavelength of 1300 nm, was capable of acquiring 3D images depicting the layered architecture of skin with axial and transverse resolutions ∼8 μm and ∼20 μm, respectively, from a volume of 7 × 3.5 × 1.5 mm3 at a frame rate of 46 Hz (1024 × 1024 pixels). This study demonstrates the clinical diagnostic potential of MPT/OCT for pre-screening relatively large areas of skin using 3D OCT to identify suspicious regions at microscopic level and subsequently using high resolution MPT to obtain zoomed in, sub-cellular level information of the respective regions (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

A recent article by Hayman, Verriotis, Jovalekic, Fenton, and Jeffery titled Anisotropic encoding of three-dimensional space by place cells and grid cells (2011) explored how place and grid cells respond when rats locomote vertically above the ground. From their results the authors concluded a number of points about rats' abilities to orient and navigate in three dimensions. Here, we review evidence revolving around several issues including: (1) what reference frame rats use when locomoting vertically, (2) whether rats can perceive their height above the ground, (3) whether rats can estimate vertical distance and have a cognitive map in the vertical domain, (4) whether rats can path integrate in the vertical domain, and (5) does processing 3-dimensional representations require a large number of neurons. We argue that the Hayman et al. results can be accounted for by considering the reference frame the animals used in the tasks. Had the rats been facing inward with their limbs in contact with the vertical surface when moving, it is possible that different patterns of place and grid cell activity would have been observed. Further, there is good evidence to indicate that rats can orient and navigate effectively in the vertical domain. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

This study evaluated the potential of utilizing transfected pTGFβ-1 gene-engineered rat mesenchymal stem cells (MSCs) using nonviral vector to promote cartilage regeneration. Pullulan-spermine was used as the nonviral gene vector and gelatin sponge was used as the scaffold. MSCs were engineered with TGF-β1 gene with either the three-dimensional (3D) reverse transfection system or the two-dimensional (2D) conventional transfection system. For the 3D reverse transfection system, pullulan-spermine/ pTGF-β1 gene complexes were immobilized to the gelatin sponge, followed by the seeding of MSCs. Pullulan-spermine/ pTGF-β1 gene complexes were delivered to MSCs cultured in the plate to perform the 2D conventional transfection system, and then MSCs were seeded to the gelatin sponge. Then, TGF-β1 gene-transfected MSC seeded gelatin sponge was implanted to the full-thickness cartilage defect. Compared with the control group, both groups of TGF-β1 gene-engineered MSCs improved cartilage regeneration through optical observation and histology staining. So, with pullulan-spermine as the nonviral vector, TGF-β1-gene engineered MSCs can induce cartilage regeneration in vivo. [ABSTRACT FROM AUTHOR]

All biological tissues are three dimensional and contain structures that span a range of length scales from nanometres through to hundreds of millimetres. These are not ideally suited to current three-dimensional characterization techniques such as X-ray or transmission electron tomography. Such detailed morphological analysis is critical to understanding the structural features relevant to tissue function and designing therapeutic strategies intended to address structural deficiencies encountered in pathological states. We show that use of focused ion beam milling combined with scanning electron microscopy can provide three-dimensional information at nanometre resolution from biologically relevant volumes of material, in this case dentine. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: To quantitatively characterize arytenoid movement induced by vocal fold injection augmentation in an excised larynx model. Study Design: Laboratory and computational. Methods: Vocal folds of human cadaveric larynges were injected with calcium hydroxylapatite. High-resolution computed tomography scans were obtained before and after injection. Densities corresponding to the arytenoid and cricoid cartilages were extracted and processed with custom MATLAB routines to generate selective three-dimensional reconstructions of the larynx. Pre- and postinjection positions of the arytenoid were compared. Results: Vocal fold injections resulted in predominantly small-magnitude medial rotation and medial translation of the arytenoid. Movements in other directions as would be expected in physiologic adduction were not observed. Conclusions: Vocal fold injection augmentation induced passive movement of the arytenoid that has not been described previously. This movement does not reproduce the trajectory of physiologic adduction. This finding has implications for the treatment of unilateral vocal fold paralysis without arytenoid repositioning maneuvers. Laryngoscope, 2010 [ABSTRACT FROM AUTHOR]

Aim To analyse volumetrically using spiral computed tomography (SCT) the efficacy of various techniques to fill root canals. Methodology Root canals in 40 maxillary central incisors were instrumented with K-files to size 60 and the volume of the canal measured using SCT. The teeth were divided into four groups of 10 each and root filled by lateral compaction, Thermafil, Obtura II and System B techniques, respectively. AH plus was used as sealer with all techniques. The filled volume in each canal was measured using SCT and the percentage of obturated volume (POV) was calculated. The data were statistically analysed using Kruskal–Wallis test and Mann–Whitney U-test. Results The four groups were comparable in canal volume. The overall POV was 80.4%, 93.3%, 84.8% and 93.7% for lateral compaction, Thermafil, Obtura II and System B, respectively ( P < 0.05). Conclusion The greatest POV was obtained with System B and Thermafil. Voids were seen in all root fillings. [ABSTRACT FROM AUTHOR]

Historically, the inability to accurately represent bitemarks and other wound patterns has limited their evidentiary value. The development of the ABFO #2 scale by Krauss and Hyzer enabled forensic odontologists to correct for most photographic plane distortions. The technique presented here uses the ABFO #2 scale in conjunction with the evolving technologies of laser scanners and comparative software commonly used by the automobile industry for three-dimensional (3D) analysis. The 3D software comparison was performed in which measurements were analyzed of the normal distance for each point on the teeth relative to the bitemarks. It created a color-mapped display of the bitemark model, with the color indicating the deviation at each point. There was a correlation between the bitemark and the original teeth. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) reconstruction of anatomical structures can give additional insight into the morphology and function of these structures. We compare 3D reconstructions of the guinea pig inner ear, using light microscopy and orthogonal plane fluorescence optical sectioning microscopy. Applications of 3D reconstruction of the inner ear are further explored. For each method two bullas were prepared for 3D reconstruction. Both methods are explained. In general, the 3D reconstructions using orthogonal plane fluorescence optical sectioning microscopy are superior to light microscopy. The exact spiral shape of the cochlea could be reconstructed using orthogonal plane fluorescence optical sectioning microscopy and the length of the basilar membrane measured. When a resolution of 20 μm is sufficient, orthogonal plane fluorescence optical sectioning microscopy is a superior technique for 3D reconstruction of inner ear structures in animals. [ABSTRACT FROM AUTHOR]

Background: There is significant interest in using nanofibers in tissue engineering from stem cells. The transdifferentiation of mesenchymal stem cells into the hepatic lineage in a nanofibrous structure has not been reported. In this study, a three dimensional nanofibrous scaffold is introduced for differentiation of human bone marrow derived mesenchymal stem cells (hBMSCs) into hepatocytes. Methods: A scaffold composed of Poly (ε-caprolactone), collagen and polyethersulfone was fabricated by the electrospinning technique. After characterization of isolated hBMSCs, the performance of the cells on the scaffold was evaluated by Scanning Electron Microscopy (SEM) and MTT assay. Cytological, molecular and biochemical markers were measured to confirm differentiation potential of hBMSCs into hepatocytes. Results: The isolated cells possessed the basic properties of mesenchymal stem cells (MSCs). Based on scanning electron microscope (SEM) analysis and MTT assay, it was shown that the cells adhere, penetrate and proliferate on the nanofibers. Cultured cells on the nanofibers differentiated into hepatocyte-like cells and expressed hepatocyte specific markers such as albumin, α-fetoprotein, cytokeratin-18, cytokeratin-19 and cytochrome P450 3A4 at mRNA levels. Appearance of a considerable number of albumin-positive cells cultivated on the scaffold (47 ± 4%) as compared to the two-dimensional culture system (28 ± 6%) indicates the supporting role of the scaffold. The efficiency of the cells to produce albumin, urea, transferrin, serum glutamic pyruvic transaminase and serum oxaloacetate aminotransferase in hepatocytes on the scaffold further attest to the functionality of the cells. Conclusion: The data presented in this study show that the engineered nanofibrous scaffold is a conductive matrix which supports and enhances MSC development into functional hepatocyte-like cells. [ABSTRACT FROM AUTHOR]

This case draws our attention to a new type of mitral valve anomaly, which seems to be congenital. A 42-year-old man with symptomatic primary severe mitral regurgitation was admitted to our hospital. Echocardiography revealed an aneurysm of the half of the valve, on the anterolateral commissure side, with significant excess tissue. The other half of the valve was normal. The two parts seemed to be separated by a continuous fibrous raphe. The anterolateral papillary muscle was hyperplasic and gave the main part of chordae tendinae. [ABSTRACT FROM AUTHOR]

The availability of multi-photon intravital microscopy has recently allowed researchers to start to visualise the dynamic behaviour of cancer cells in vivo. This imaging has revealed that many cancer cells ranging from carcinoma to melanoma move in an amoeboid manner in order to invade surrounding tissue and escape from the primary tumour. This mode on cell motility is extremely rapid and does not require the activity of proteases to degrade the extra-cellular matrix (ECM). This review details the techniques that are available to study cell motility in vivo and discusses the current knowledge about the mechanisms of amoeboid cell motility. [ABSTRACT FROM AUTHOR]

Anatomical information at the cellular level is important in many fields, including organ systems development, computational biology and informatics. Creating data sets at resolutions that provide enough detail to reconstruct cellular structures across tissue volumes from 1 to 100 mm3 has proven to be difficult and time-consuming. In this paper, we describe a new method for staining and imaging large volumes of tissue at sub-micron resolutions. Serial sections are cut using an automated ultra-microtome, whereas concurrently each section is imaged through a light microscope with a high-speed line-scan camera. This technique, knife-edge scanning microscopy, allows us to view and record large volumes of tissue in a relatively small amount of time (approximately 7 mm2 s−1). The resolution and scanning speed of knife-edge scanning microscopy provides a new method for imaging tissue at sufficient resolution to reconstruct maps of cellular distribution and morphology. We show that these techniques preserve the alignment of serial sections accurately enough to allow for reconstruction of neuronal processes and microvasculature. Expanding these techniques to other tissues opens up the possibility of creating fully reconstructed cellular maps of entire organs. [ABSTRACT FROM AUTHOR]

The study reported here employed the physics-based Integrated Hydrology Model (InHM) to conduct continuous hydrologic-response simulation from 1990 through 1996 for the Coos Bay experimental catchment. The uniqueness of the boundary-value problem used to simulate three sprinkling experiments was assessed, via model performance evaluation against observed piezometric and discharge data, for 33 events extracted from the continuous record. The InHM simulations could not adequately reproduce the distributed observed pore water pressures, suggesting that detailed characterization of the locations and connectivities of bedrock fractures is critical for future efforts designed to simulate distributed hydrologic response at the field scale for locations where bedrock fracture flow is important. The simulations presented here suggest the potential for interaction between the deeper water table and near-surface hydrologic response. The results reported herein suggest that while uniqueness can be reasonably achieved with respect to the integrated response (i.e., discharge), the integrated response uniqueness is no guarantee that the distributed response (i.e., pressure head) is either unique or well simulated. [ABSTRACT FROM AUTHOR]

The article describes an approach for the examination of the fetal heart using an algorithm that allows the simultaneous visualization of the standard planes for fetal echocardiography. It discusses the application of the algorithm to volume datasets from fetuses with congenital heart disease (CHD). It also offers images from fetuses with and without CHD, confirmed postnatally by echocardiography, surgery or during autopsy.

Objectives: High resolution two-dimensional ultrasound (2D US) difficulty in evaluation of some scrotal mass lesions is not frequent. The aim of the present study was to prospectively evaluate the diagnostic performance of three-dimensional ultrasound extended imaging (3D XI) in characterization of those lesions. Methods: The study protocol had the approval of the University's review board all participants' informed consents were obtained. The study included 28 selected patients (12 testicular and 16 para-testicular mass lesions) examined by 2D US and 3D XI applications including computed multi-slice view (MSV) and multi-resolution enhanced images (XI MR). Results were correlated with histopathological findings. Results: Two-dimensional ultrasound did not adequately characterize 28 patients out of 329 (8.5%). 3D XI interrogation was an easy procedure and distinctive of the pathological findings in 27 patients out of 28 (96.4%). The performance of XI MR with respect to characterization provided additional diagnostic information over MSV. Conclusions: The performance of 3D XI with respect to testicular mass characterization proved better than static 2D US. Subsequently, the results of this study suggest that the routine use of 2D US in diagnosis of scrotal mass lesions should preferably be upgraded to 3D XI methods. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop a simple, safe, minimally invasive protocol to evaluate the hepatic vasculature. Five purpose-bred Beagle dogs underwent noncontrast-enhanced computed tomographic scan of the entire abdomen. A dynamic, nonincremental computed tomography scan at the level of T11 was then performed using a test bolus of contrast medium to determine time to peak opacification and to aid in the calculation of scan delay. The time to peak arterial enhancement ranged from 2.0 to 7.0 s, with a median of 2.0 s. The time to peak portal venous enhancement ranged from 23.0 to 46.0 s, with a median of 32.0 s. Scan delay for arterial opacification ranged from 0 to 5.0 s, with a median of 0 s. Scan delay for the portal phase of opacification ranged from 6.0 to 21.0 s, with a median of 17.0 s. Using this information, two separate computed tomographic studies were used to image the arterial and portal venous phases of circulatory opacification, respectively. The dogs were hyperventilated to prevent breathing motion during the scan, each of which required approximately 20 s. A power injector was used to inject diatrizoate meglumine (128 mg I/kg) through an 18-gauge cephalic vein catheter at a rate of 5 ml/s. Scanning was initiated after the appropriate scan delay to optimize the specific phase of vascular filling. Maximum intensity projections allowed clear delineation of the hepatic arteries and the portal venous system, while eliminating overlying structures that might interfere with image analysis. Time/density curves were generated, and the time needed for each study was recorded. Hepatic arteries and portal veins were clearly visualized in all dogs. Parenchymal opacification was also observed. [ABSTRACT FROM AUTHOR]

Summary. Determining the cellular distribution of key adhesion molecules may aid in understanding haematopoietic progenitor/stem cell (HPSC) homing to bone marrow (BM). CD34, a well-characterized marker for blast-like HPSC, is widely used for the isolation and enumeration of HPSC. Functional studies have yet to identify a ligand for CD34. However, growing evidence suggests that CD34 may aid the regulation of HPSC differentiation and modulate the expression of other HPSC adhesion molecules necessary for homing. This study aimed to determine CD34 distribution on umbilical cord blood (CB) and BM. CD34-selected cells were adhered to positively charged gold slides at room temperature, before indirect fluorescent antibody labelling with fluorescein isothiocyanate. Fluorescent distribution was determined by 1-µm interval, confocal laser scanning microscope Z-sections. Initial analysis showed CD34 distributed within peripheral halos and dense pocket regions. The development of three-dimensional imaging software enabled spatial visualization of CD34 distribution on CB and BM in association with differential interference contrast cell image. This showed that CD34 was distributed within peripheral halos, with magnupodia-associated ‘meridian-shaped crescents’, extending from points of cell–slide adhesion towards the top of the cell. True CD34 distribution, not previously discernible by confocal laser scanning microscopy alone, suggests a possible role in cell adhesion/homing revealed by three-dimensional imaging. [ABSTRACT FROM AUTHOR]

This paper presents an efficient reconstruction algorithm for three-dimensional scattering objects. The algorithm is an extension of previous work for the two-dimensional one, and is based on an optimization procedure. From the computer simulations, the proposed method is shown to yield satisfactory results, and to not be so sensitive to the presence of noise. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 332–336, 2001. [ABSTRACT FROM AUTHOR]

A three dimensional (3D) solution in terms of potential functions is presented for a finite clamped circular isotropic elastic plate bonded to a piezoceramic plate subjected to axisymmetric thermoelectromechanical load. The boundary and interface conditions are satisfied using Fourier-Bessel expansions yielding an infinite system of algebraic equations for the arbitrary constants. These are solved to any desired degree of accuracy by truncating to a finite set of equations. Results are presented to illustrate the effect of the thickness parameter. The present solution would help to ascertain the accuracy and range of validity of two dimensional (2D) theories of piezoelectric hybrid plates. [ABSTRACT FROM AUTHOR]