The convergent cavopulmonary connection: A novel and efficient configuration of Fontan to accommodate mechanical support.

Objective: The current total cavopulmonary connection Fontan has competing inflows and outflows, creating hemodynamic inefficiencies that contribute to Fontan failure and complicate placement and efficiency of mechanical circulatory support. We propose a novel convergent cavopulmonary connection (CCPC) Fontan design to create a single, converged venous outflow to the pulmonary arteries, thus increasing efficiency and mechanical circulatory support access. We then evaluate the feasibility and hemodynamic performance of the CCPC in various patient sizes using computational fluid dynamic assessments of computer-aided designs. Methods: Cardiac magnetic resonance imaging data from 12 patients with single ventricle (10 total cavopulmonary connection, 2 Glenn) physiology (body surface area, 0.5-2.0 m2) were segmented to create 3-dimensional replicas of all thoracic structures. Surgically feasible CCPC shapes within constraints of anatomy were created using iterative computational fluid dynamic and clinician input. Designs varied based on superior and inferior vena cava conduit sizes, coronal attachment height, coronal entry angle, and axial entry angle of the superior vena cava to the inferior vena cava. CCPC designs were optimized based on efficiency (indexed power loss), risk of arteriovenous malformations (hepatic flow distribution), and risk of flow stasis (% nonphysiologic wall shear stress). Results: All CCPC designs met hemodynamic performance thresholds for indexed power loss and hepatic flow distribution. CCPC designs showed improvements in reducing % nonphysiologic wall shear stress and balancing HFD. Conclusions: CCPC is physiologically and surgically feasible in various patient sizes using validated computational fluid dynamic models. CCPC configuration has analogous indexed power loss, hepatic flow distribution, and % nonphysiologic wall shear stress compared with total cavopulmonary connection, and the single inflow and outflow may ease mechanical circulatory support therapies. Further studies are required for design optimization and mechanical circulatory support institution.

Anthropometric, physical activity, and psychological characteristics of Korean adults with and without developmental coordination disorder (DCD).

Developmental Coordination Disorder (DCD), also known as Dyspraxia, is characterized by movement difficulties in individuals without discernible neurological disorders or identifiable medical conditions. Previous studies from various countries have highlighted disparities in anthropometric, physical activity, and psychological characteristics between children diagnosed with DCD and their typically developing (TD) peers. These differences are influenced by sociocultural norms and geographical locations. However, little attention has been given to scrutinizing analogous differences in adult populations, particularly within Republic of Korea. This study aims to address this knowledge gap by employing a battery of questionnaires to assess anthropometric, physical activity, and psychological traits in a cohort of 377 Korean adults, encompassing those with DCD (n = 54) alongside TD counterparts (n = 323). It was hypothesized that Korean adults with DCD would exhibit higher body mass index and lower ratings in physical activity and psychological characteristics than TD, consistent with the previous studies performed in other countries on children. The results showed no statistically significant differences between the DCD and TD groups in anthropometric characteristics such as weight (kg), height (cm), and body mass index. The prevalence of walking and biking for daily commuting in daily routines within Korean society might have contributed to the mitigation of anthropometric among individuals with/without DCD. Statistically significant differences were found in physical activity levels at work and recreational settings, as shown in physical activity scores and duration. The DCD group also displayed lower scores across several psychological characteristics, including exercise adherence, intrinsic motivation, self-efficacy, physical self-concept, exercise expectations, and intrinsic regulation. These findings underscore the necessity of incorporating sociocultural dynamics when investigating anthropometric, physical activity, and psychological characteristics in adults with DCD. Their perceived difficulties in fine motor skills were also significantly poor than TD. Future research studies are warranted to elucidate the underlying mechanisms driving the observed patterns in this study, thus contributing to a more nuanced comprehension of how DCD manifests within specific sociocultural contexts.

Antifouling Surface Coating on Various Substrates by Inducing Tyrosinase-Mediated Oxidation of a Tyrosine-Conjugated Sulfobetaine Derivative.

Inspired by the melanogenesis occurring in nature, we report tyrosinase-mediated antifouling surface coating by synthesizing a tyrosine-conjugated sulfobetaine derivative (Tyr-SB). Synthetic Tyr-SB contains zwitterionic sulfobetaine and tyrosine, whose phenolic amine group acts as a dormant coating precursor. In contrast to catecholamine derivatives, tyrosine derivatives are stable against auto-oxidation and are enzymatically oxidized only in the presence of tyrosinase to initiate melanin-like oxidation. When the surface of interest was applied during the course of Tyr-SB oxidation, a superhydrophilic poly(Tyr-SB) film was coated on the surfaces, thereby showing antifouling performance against proteins or adherent cells. Because the oxidation of Tyr-SB occurred under mild aqueous conditions (pH 6-7) without the use of any chemical oxidants, such as sodium periodate or ammonium persulfate, we anticipate that the coating method described herein will serve as a biocompatible tool in the field of biosensors, cell surface engineering, and medical devices, whose interfaces differ in chemistry.

Virtual Reality Cardiac Surgical Planning Software (CorFix) for Designing Patient-Specific Vascular Grafts: Development and Pilot Usability Study.

BACKGROUND: Patients with single ventricle heart defects receive 3 stages of operations culminating in the Fontan procedure. During the Fontan procedure, a vascular graft is sutured between the inferior vena cava and pulmonary artery to divert deoxygenated blood flow to the lungs via passive flow. Customizing the graft configuration can maximize the long-term benefits. However, planning patient-specific procedures has several challenges, including the ability for physicians to customize grafts and evaluate their hemodynamic performance. OBJECTIVE: The aim of this study was to develop a virtual reality (VR) Fontan graft modeling and evaluation software for physicians. A user study was performed to achieve 2 additional goals: (1) to evaluate the software when used by medical doctors and engineers, and (2) to explore the impact of viewing hemodynamic simulation results in numerical and graphical formats. METHODS: A total of 5 medical professionals including 4 physicians (1 fourth-year resident, 1 third-year cardiac fellow, 1 pediatric intensivist, and 1 pediatric cardiac surgeon) and 1 biomedical engineer voluntarily participated in the study. The study was pre-scripted to minimize the variability of the interactions between the experimenter and the participants. All participants were trained to use the VR gear and our software, CorFix. Each participant designed 1 bifurcated and 1 tube-shaped Fontan graft for a single patient. A hemodynamic performance evaluation was then completed, allowing the participants to further modify their tube-shaped design. The design time and hemodynamic performance for each graft design were recorded. At the end of the study, all participants were provided surveys to evaluate the usability and learnability of the software and rate the intensity of VR sickness. RESULTS: The average times for creating 1 bifurcated and 1 tube-shaped graft after a single 10-minute training session were 13.40 and 5.49 minutes, respectively, with 3 out 5 bifurcated and 1 out of 5 tube-shaped graft designs being in the benchmark range of hepatic flow distribution. Reviewing hemodynamic performance results and modifying the tube-shaped design took an average time of 2.92 minutes. Participants who modified their tube-shaped graft designs were able to improve the nonphysiologic wall shear stress (WSS) percentage by 7.02%. All tube-shaped graft designs improved the WSS percentage compared to the native surgical case of the patient. None of the designs met the benchmark indexed power loss. CONCLUSIONS: VR graft design software can quickly be taught to physicians with no engineering background or VR experience. Improving the CorFix system could improve performance of the users in customizing and optimizing grafts for patients. With graphical visualization, physicians were able to improve WSS percentage of a tube-shaped graft, lowering the chance of thrombosis. Bifurcated graft designs showed potential strength in better flow split to the lungs, reducing the risk for pulmonary arteriovenous malformations.

Computational Fontan Analysis: Preserving Accuracy While Expediting Workflow.

Background: Postoperative outcomes of the Fontan operation have been linked to geometry of the cavopulmonary pathway, including graft shape after implantation. Computational fluid dynamics (CFD) simulations are used to explore different surgical options. The objective of this study is to perform a systematic in vitro validation for investigating the accuracy and efficiency of CFD simulation to predict Fontan hemodynamics. Methods: CFD simulations were performed to measure indexed power loss (iPL) and hepatic flow distribution (HFD) in 10 patient-specific Fontan models, with varying mesh and numerical solvers. The results were compared with a novel in vitro flow loop setup with 3D printed Fontan models. A high-resolution differential pressure sensor was used to measure the pressure drop for validating iPL predictions. Microparticles with particle filtering system were used to measure HFD. The computational time was measured for a representative Fontan model with different mesh sizes and numerical solvers. Results: When compared to in vitro setup, variations in CFD mesh sizes had significant effect on HFD (P = .0002) but no significant impact on iPL (P = .069). Numerical solvers had no significant impact in both iPL (P = .50) and HFD (P = .55). A transient solver with 0.5 mm mesh size requires computational time 100 times more than a steady solver with 2.5 mm mesh size to generate similar results. Conclusions: The predictive value of CFD for Fontan planning can be validated against an in vitro flow loop. The prediction accuracy can be affected by the mesh size, model shape complexity, and flow competition.

Surgical Planning and Optimization of Patient-Specific Fontan Grafts With Uncertain Post-Operative Boundary Conditions and Anastomosis Displacement.

OBJECTIVE: Fontan surgical planning involves designing grafts to perform optimized hemodynamic performance for the patient's long-term health benefit. The uncertainty of post-operative boundary conditions (BC) and graft anastomosis displacements can significantly affect optimized graft designs and lead to undesirable outcomes, especially for hepatic flow distribution (HFD). We aim to develop a computation framework to automatically optimize patient-specific Fontan grafts with the maximized possibility of keeping post-operative results within clinical acceptable thresholds. METHODS: The uncertainties of BC and anastomosis displacements were modeled using Gaussian distributions according to prior research studies. By parameterizing the Fontan grafts, we built surrogate models of hemodynamic parameters taking the design parameters and BC as input. A two-phase reliability-based robust optimization (RBRO) strategy was developed by combining deterministic optimization (DO) and optimization under uncertainty (OUU) to reduce computational cost. RESULTS: We evaluated the performance of the RBRO framework by comparing it with the DO method in four cases of Fontan patients. The results showed that the surgical plans computed from the proposed method yield up to 79.2% improvement in the reliability of the HFD than those of the DO method ( ). The mean values of indexed power loss (iPL) and the percentage of non-physiologic wall shear stress (%WSS) for the optimized surgical plans met the clinically acceptable thresholds. CONCLUSION: This study demonstrated the effectiveness of our RBRO framework to address the uncertainties of BC and anastomosis displacements for Fontan surgical planning. SIGNIFICANCE: The technique developed in this paper demonstrates a significant improvement in the reliability of the predicted post-operative outcomes for Fontan surgical planning. This planning technique is immediately applicable as a building block to enable technology for optimal long-term outcomes for pediatric Fontan patients and can also be used in other pediatric and adult cardiac surgeries.

Semi-Automatic Planning and Three-Dimensional Electrospinning of Patient-Specific Grafts for Fontan Surgery.

This paper proposes a semi-automatic Fontan surgery planning method for designing and manufacturing hemodynamically optimized patient-specific grafts. Fontan surgery is a palliative procedure for patients with a single ventricle heart defect by creating a new path using a vascular graft for the deoxygenated blood to be directed to the lungs, bypassing the heart. However, designing patient-specific grafts with optimized hemodynamic performance is a complex task due to the variety of patient-specific anatomies, confined surgical planning space, and the requirement of simultaneously considering multiple design criteria for vascular graft optimization. To address these challenges, we used parameterized Fontan pathways to explore patient-specific vascular graft design spaces and search for optimal solutions by formulating a nonlinear constrained optimization problem, which minimizes indexed power loss (iPL) of the Fontan model by constraining hepatic flow distribution (HFD), percentage of abnormal wall shear stress (%WSS) and geometric interference between Fontan pathways and the heart models (InDep) within clinically acceptable thresholds. Gaussian process regression was employed to build surrogate models of the hemodynamic parameters as well as InDep and [Formula: see text] (conduit model smoothness indicator) for optimization by pattern search. We tested the proposed method on two patient-specific models (n=2). The results showed the automatically optimized (AutoOpt) Fontan models hemodynamically outperformed or at least are comparable to manually optimized Fontan models with significantly reduced surgical planning time (15 hours versus over 2 weeks). We also demonstrated feasibility of manufacturing the AutoOpt Fontan conduits by using electrospun nanofibers.

The conceptual building blocks of everyday thought: Tracking the emergence and dynamics of ruminative and nonruminative thinking.

How do thoughts arise, unfold, and change over time? Are the contents and dynamics of everyday thought rooted in conceptual associations within one's semantic networks? To address these questions, we developed the Free Association Semantic task (FAST), whereby participants generate dynamic chains of conceptual associations in response to seed words that vary in valence. Ninety-four adults from a community sample completed the FAST task and additionally described and rated six of their most frequently occurring everyday thoughts. Text analysis and valence ratings revealed similarities in thematic and affective content between FAST concept chains and recurrent autobiographical thoughts. Dynamic analyses revealed that individuals higher in rumination were more strongly attracted to negative conceptual spaces and more likely to remain there longer. Overall, these findings provide quantitative evidence that conceptual associations may act as a semantic scaffold for more complex everyday thoughts, and that more negative and less dynamic conceptual associations in ruminative individuals mirror maladaptive repetitive thoughts in daily life. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Posttranscriptional modulation of KCNQ2 gene expression by the miR-106b microRNA family.

MicroRNAs (miRNAs) have recently emerged as important regulators of ion channel expression. We show here that select miR-106b family members repress the expression of the KCNQ2 K+ channel protein by binding to the 3'-untranslated region of KCNQ2 messenger RNA. During the first few weeks after birth, the expression of miR-106b family members rapidly decreases, whereas KCNQ2 protein level inversely increases. Overexpression of miR-106b mimics resulted in a reduction in KCNQ2 protein levels. Conversely, KCNQ2 levels were up-regulated in neurons transfected with antisense miRNA inhibitors. By constructing more specific and stable forms of miR-106b controlling systems, we further confirmed that overexpression of precursor-miR-106b-5p led to a decrease in KCNQ current density and an increase in firing frequency of hippocampal neurons, while tough decoy miR-106b-5p dramatically increased current density and decreased neuronal excitability. These results unmask a regulatory mechanism of KCNQ2 channel expression in early postnatal development and hint at a role for miR-106b up-regulation in the pathophysiology of epilepsy.

A Novel Virtual Reality Medical Image Display System for Group Discussions of Congenital Heart Disease: Development and Usability Testing.

BACKGROUND: The complex 3-dimensional (3D) nature of anatomical abnormalities in congenital heart disease (CHD) necessitates multidisciplinary group discussions centered around the review of medical images such as magnetic resonance imaging. Currently, group viewings of medical images are constrained to 2-dimensional (2D) cross-sectional displays of 3D scans. However, 2D display methods could introduce additional challenges since they require physicians to accurately reconstruct the images mentally into 3D anatomies for diagnosis, staging, and planning of surgery or other therapies. Virtual reality (VR) software may enhance diagnosis and care of CHD via 3D visualization of medical images. Yet, present-day VR developments for medicine lack the emphasis on multiuser collaborative environments, and the effect of displays and level of immersion for diagnosing CHDs have not been studied. OBJECTIVE: The objective of the study was to evaluate and compare the diagnostic accuracies and preferences of various display systems, including the conventional 2D display and a novel group VR software, in group discussions of CHD. METHODS: A total of 22 medical trainees consisting of 1 first-year, 10 second-year, 4 third-year, and 1 fourth-year residents and 6 medical students, who volunteered for the study, were formed into groups of 4 to 5 participants. Each group discussed three diagnostic cases of CHD with varying structural complexity using conventional 2D display and group VR software. A group VR software, Cardiac Review 3D, was developed by our team using the Unity engine. By using different display hardware, VR was classified into nonimmersive and full-immersive settings. The discussion time, diagnostic accuracy score, and peer assessment were collected to capture the group and individual diagnostic performances. The diagnostic accuracies for each participant were scored by two experienced cardiologists following a predetermined answer rubric. At the end of the study, all participants were provided a survey to rank their preferences of the display systems for performing group medical discussions. RESULTS: Diagnostic accuracies were highest when groups used the full-immersive VR compared with the conventional and nonimmersive VR (χ22=9.0, P=.01) displays. Differences between the display systems were more prominent with increasing case complexity (χ22=14.1, P<.001) where full-immersive VR had accuracy scores that were 54.49% and 146.82% higher than conventional and nonimmersive VR, respectively. The diagnostic accuracies provided by the two cardiologists for each participant did not statistically differ from each other (t=-1.01, P=.31). The full-immersive VR was ranked as the most preferred display for performing group CHD discussions by 68% of the participants. CONCLUSIONS: The most preferred display system among medical trainees for visualizing medical images during group diagnostic discussions is full-immersive VR, with a trend toward improved diagnostic accuracy in complex anatomical abnormalities. Immersion is a crucial feature of displays of medical images for diagnostic accuracy in collaborative discussions.

NCAPH Is Required for Proliferation, Migration and Invasion of Non-small-cell Lung Cancer Cells.

BACKGROUND/AIM: Non-structural maintenance of chromosomes condensin I complex subunit H (NCAPH) is implicated in correct chromosome condensation and segregation during mitosis. However, the functional role of NCAPH in the pathogenesis of non-small-cell lung cancer (NSCLC) remains unclear. The aim of this study was to elucidate the role of NCAPH in NSCLC cells. MATERIALS AND METHODS: A549 and H1299 NSCLC cells were transfected with small-interfering RNA (siRNA) against NCAPH. Subsequently, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, colony-formation assay and flow cytometry analysis were performed to reveal the role of NCAPH in NSCLC cells. In addition, migration and invasion assay were also performed. RESULTS: NCAPH knockdown inhibited cell proliferation, induced cell-cycle arrest at G2/M phase, and prevented colony formation, migration and invasion by NSCLC cells. CONCLUSION: NCAPH is involved in NSCLC progression and development, and may be a potential therapeutic target for NSCLC treatment.

Oncogenic Ras downregulates mdr1b expression through generation of reactive oxygen species.

In the present study, we investigated the effect of oncogenic H-Ras on rat mdr1b expression in NIH3T3 cells. The constitutive expression of H-RasV12 was found to downregulate the mdr1b promoter activity and mdr1b mRNA expression. The doxorubicin-induced mdr1b promoter activity of the H-RasV12 expressing NIH3T3 cells was markedly lower than that of control NIH3T3 cells. Additionally, there is a positive correlation between the level of H-RasV12 expression and a sensitivity to doxorubicin toxicity. To examine the detailed mechanism of H-RasV12-mediated down-regulation of mdr1b expression, antioxidant N-acetylcysteine (NAC) and NADPH oxidase inhibitor diphenylene iodonium (DPI) were used. Pretreating cells with either NAC or DPI significantly enhanced the oncogenic H-Ras-mediated down-regulation of mdr1b expression and markedly prevented doxorubicin-induced cell death. Moreover, NAC and DPI treatment led to a decrease in ERK activity, and the ERK inhibitors PD98059 or U0126 enhanced the mdr1b-Luc activity of H-RasV12-NIH3T3 and reduced doxorubicin-induced apoptosis. These data suggest that RasV12 expression could downregulate mdr1b expression through intracellular reactive oxygen species (ROS) production, and ERK activation induced by ROS, is at least in part, contributed to the downregulation of mdr1b expression.

Knockdown of CARD14 Inhibits Cell Proliferation and Migration in Breast Cancer Cells.

BACKGROUND/AIM: Caspase recruitment domain family, member 14 (CARD14) is a member of the CARD family of proteins, which play an important role in immune and inflammatory response, and cell survival and proliferation. Here, we identified the role of CARD14 in human breast cancer. MATERIALS AND METHODS: Immunohistochemistry was performed to evaluate CARD14 expression in breast cancer. Using CARD14 knockdown cells by small interfering RNA, colony formation and MTT assays, flow cytometry analyses, and migration assays were performed to evaluate the proliferation, cell cycle distribution, apoptosis, and migration ability of MCF7 and SK-BR-3 cells. RESULTS: CARD14 expression was significantly higher in breast cancer samples than in normal breast samples. CARD14 knockdown inhibited cell proliferation and migration, caused cell cycle arrest at the G1/S boundary, and promoted apoptosis. CONCLUSION: CARD14 regulates the proliferation and migration of MCF7 and SK-BR-3 cells; it is thus, a novel potential therapeutic target in breast cancer.

Role of surgeon intuition and computer-aided design in Fontan optimization: A computational fluid dynamics simulation study.

OBJECTIVE: Customized Fontan designs, generated by computer-aided design (CAD) and optimized by computational fluid dynamics simulations, can lead to novel, patient-specific Fontan conduits unconstrained by off-the-shelf grafts. The relative contributions of both surgical expertise and CAD to Fontan optimization have not been addressed. In this study, we assessed hemodynamic performance of Fontans designed by both surgeon's unconstrained modeling (SUM) and by CAD. METHODS: Ten cardiac magnetic resonance imaging datasets were used to create 3-dimensional (3D) models of Fontans. Baseline computational fluid dynamics simulations assessed Fontan indexed power loss (iPL), hepatic flow distribution, and percentage of conduit surface area with abnormally low wall shear stress for venous flow (<1 dyne/cm2). Fontans not meeting thresholds were redesigned using 2 methods: SUM (ie, original venous anatomy without the Fontan was 3D printed and sent to surgeon for Fontan redesign with clay modeling) and CAD (ie, the same 3D geometry was sent to engineers for iterative Fontan redesign guided by computational fluid dynamics). Both groups were blinded to each other's results. RESULTS: Eight Fontans were redesigned by SUM and CAD methods. Both SUM and CAD redesigns met iPL thresholds. SUM had lower iPL, whereas CAD demonstrated balanced hepatic flow distribution and lower wall shear stress percentage. Wall shear stress percentage shared an inverse relationship with iPL, preventing oversized Fontan designs. CONCLUSIONS: Customized Fontan conduits with low iPL can be created by either a surgeon or CAD. CAD can also improve hepatic flow distribution and prevent oversized Fontan designs. Future studies should investigate workflows that combine SUM and CAD to optimize Fontan conduits.

In vivo implantation of 3-dimensional printed customized branched tissue engineered vascular graft in a porcine model.

BACKGROUND: The customized vascular graft offers the potential to simplify the surgical procedure, optimize physiological function, and reduce morbidity and mortality. This experiment evaluated the feasibility of a flow dynamic-optimized branched tissue engineered vascular graft (TEVG) customized based on medical imaging and manufactured by 3-dimensional (3D) printing for a porcine model. METHODS: We acquired magnetic resonance angiography and 4-dimensional flow data for the native anatomy of the pigs (n = 2) to design a custom-made branched vascular graft of the pulmonary bifurcation. An optimal shape of the branched vascular graft was designed using a computer-aided design system informed by computational flow dynamics analysis. We manufactured and implanted the graft for pulmonary artery (PA) reconstruction in the porcine model. The graft was explanted at 4 weeks after implantation for further evaluation. RESULTS: The custom-made branched PA graft had a wall shear stress and pressure drop (PD) from the main PA to the branch PA comparable to the native vessel. At the end point, magnetic resonance imaging revealed comparable left/right pulmonary blood flow balance. PD from main PA to branch between before and after the graft implantation was unchanged. Immunohistochemistry showed evidence of endothelization and smooth muscle layer formation without calcification of the graft. CONCLUSIONS: Our animal model demonstrates the feasibility of designing and implanting image-guided, 3D-printed, customized grafts. These grafts can be designed to optimize both anatomic fit and hemodynamic properties. This study demonstrates the tremendous potential structural and physiological advantages of customized TEVGs in cardiac surgery.

Development of Unmanned Excavator Vehicle System for Performing Dangerous Construction Work.

Of all the machinery and equipment used on construction sites, excavators are responsible for the greatest number of fatal accidents. Excavation is an inherently risky process due to imprecise work processes and the unstable external environment on most work sites. The resulting accidents cause serious injuries that threaten the lives of not only the excavator pilots but also those working around them. In this study, we propose a mechanical device that is capable of operating the excavator remotely from a nearby safe location such as a site office. To ensure worker safety and at the same time boost the productivity of excavation operations, data from 3D scanners, cameras, and sensors were combined to create a detailed 3D picture of the area surrounding the excavation site to guide a remotely operated excavating system. Rather than modifying the excavator itself, a removable manipulator was mounted on the joystick in the excavator's cockpit. Our proposed system was tested on a standard commercial excavator to verify its performance for a real-world excavation task.

Quantitative computed tomographic evaluation of bone mineral density in beagle dogs: comparison with dual-energy x-ray absorptiometry as a gold standard.

This study aimed to demonstrate the higher accuracy and reproducibility of quantitative computed tomography (QCT) compared with dual-energy X-ray absorptiometry (DXA) as a gold standard for measuring canine bone mineral density (BMD). Seven middle-aged beagle dogs underwent lumbar vertebral and bilateral femoral DXA and QCT scans. BMD (mg/cm2) was measured at the vertebral body from L2 to L6, femoral neck, and proximal and distal femoral diaphyses. The BMD values were measured 3 times and compared. The BMD value on QCT was higher than that on DXA for femoral BMD but not for vertebral BMD. The correlation was strong for the lumbar vertebrae (r=0.66) and was strongest for L3 (r=0.85). No correlation was found for the femoral neck (P=0.35), and only moderate correlations were found for the proximal and distal femoral diaphyses (r=0.43 and r=0.40, respectively). The limits of agreement were narrower for vertebral BMD than for femoral BMD, and L3 had the narrowest limits of agreement. The intraclass correlation (ICC) was higher for DXA than for QCT at all lumbar and femoral sites measured, but the ICC of QCT was higher than 0.7. In conclusion, L3 can be used to monitor changes in BMD, and relative values and sequential monitoring of femoral BMD can also be useful because of the high reproducibility of QCT measurements. QCT would be a useful technique for evaluation of BMD in veterinary practice.

Formation of Anodic Aluminum Oxide with Branched and Meshed Pores.

Anodic aluminum oxide (AAO), with a self-ordered hexagonal array, is important for various applications in nanofabrication including as the fabrication of nanotemplates and other nanostructures. With the consideration, there have been many efforts to control the characteristic parameters of porous anodic alumina by adjustment of the anodizing conditions such as the electrolyte, temperature, applied potential, and Al purity. In particular, impurities in Al are changing the morphology of an alumina film; however, the formation mechanism has not yet been explained. In this work, we anodized a high purity (99.999%, Al(high)) and low purity (99.8%, Al(low)) aluminum foil by a two-step anodization process in an oxalic acid solution or phosphoric acid. It was found that the purity of aluminum foil has influenced the morphology of the alumina film resulting in branched and meshed pores. Also, electrochemical analysis indicated that the branched and meshed pores in the low-purity Al foil formed by the presence of impurities. Impurities act as defects and change the general growth mechanism for pore formation by inducing an electric field imbalance during anodization. This work contributes to the research field of topographical chemistry and applied fields including nanofabrication.