Complex 3D Structure Research Articles

3D printed composite model of pelvic osteochondroma and nerve roots

Background3D-printing has become increasingly utilized in the preoperative planning of clinical orthopaedics. Surgical treatment of bone tumours within the pelvis is challenging due to the complex 3D bone structure geometry, as well as the proximity of vital structures. We present a unique case where a composite bone and nerve model of the lower lumbar spine, pelvis and accompanying nerve roots was created using 3D-printing. The 3D-printed model created an accurate reconstruction of the pelvic tumour and traversing nerves for preoperative planning and allowed for efficient and safe surgery.Case presentationWe present a unique case where a composite bone and nerve model of the lower lumbar spine, pelvis and accompanying nerve roots was created using 3D-printing. The bony pelvis and spine model was created using the CT, whereas the nerve roots were derived from the MRI and printed in an elastic material. 3D-printed model created an accurate reconstruction of the pelvic tumour and traversing nerves for preoperative planning and allowed for efficient and safe surgery. Pelvic tumour surgery is inherently dangerous due to the delicate nature of the surrounding anatomy. The composite model enabled the surgeon to very carefully navigate the anatomy with a focused resection and extreme care knowing the exact proximity of the L3 and L4 nerve roots.ConclusionThe patient had complete resection of this tumour, no neurological complication and full resolution of his symptoms due to careful, preoperative planning with the use of the composite 3D model.

Micro electrical discharge milling of a monocrystalline silicon complex micro-cavity

ABSTRACT This paper develops a new method to restrain the fracture of monocrystalline silicon machining in EDM (Electrical discharge machining) through controlling the topography of single discharge crater. By this method, the complex 3D micro-cavity can be machined without obvious fracture. The fracture of monocrystalline silicon in EDM was revealed according to the EDM pits and the machining debris, then it is inferred that there are two ways to cause fractures, one is the breakages at the edge of the effective-removing crater, and the other way is the deformation accumulation caused by the superposition of the ineffective-removing crater. Then, it was found that if the morphology of single discharge crater can be controlled, the less fracture can be guaranteed during the manufacturing. Using narrow pulse width discharge, plenty of experimental tests were carried out focused on carters and surface of monocrystalline silicon with different machining parameters, with the assistance of characterization and analysis. Using these new results, the complex 3D structure is machined by layered compensation strategy and step-by-step milling strategy. It is found from the as-machined complex 3D cavity that it has no obvious defects at the edges, and the fracture is controlled.

FPGA implementation of high‐speed tunable IIR band pass notch filter for identification of hot‐spots in protein

SummaryLocalization of hot spots in a protein sequence is an important problem for understanding complex 3D structure of amino acid sequence (due to which biological functionality of protein is performed by their mutual interactions). Several digital signal processing (DSP) techniques like digital filtering, wavelet, and Fourier transforms have been used for finding the hot‐spot locations. Fast processing of these longer protein sequences is desirable. Field Programmable Gate Array (FPGA) implementation of Infinite Impulse Response (IIR) band pass notch (BPN) digital filter (tuned automatically by characteristics frequency of protein family) is carried out in this paper for further speed‐up of this protein analysis process. Performance of proposed filter system (implemented on Zynq series Zybo board FPGA) is further improved using retiming, which has significantly increased the maximum clock frequency from 34.304 to 54.812 MHz. Simulation of both MATLAB and FPGA hardware implementation for BPN IIR filter is executed on 10 protein functional groups. The simulation results predict the same hot‐spots locations as mentioned in ASEdb data base, but the Hardware BPN IIR filter (proposed in this paper) is 190 to 278 times faster as compared to its MATLAB counterpart. Some additional new hot‐spot locations (not mentioned in ASEdb data base) have been determined by our proposed hardware filter, which can be the probable hot‐spots for newly identified proteins.

Three-dimensional visualization and characterization of paper machine felts and their relationship to their properties and dewatering performance

Polymeric felts are commonly used in the papermaking process on the paper machine wet end, in the press section, and in the dryer section. They provide an important function during paper manufacturing, including as a carrier or support; as a filter media assisting with water removal on the paper machine; in retention of fibers, fines, and fillers; and in some applications, such as tissue and towel, to impart key structural features to the web. These felts can have highly interwoven complex internal structures comprised of machine direction and cross-machine direction yarns of varying sizes and chemical compositions. Here, we present a non-intrusive three-dimensional (3D) image visualization method using advanced X-ray computed tomography (XRCT). This method was used to characterize the complex 3D felt structure and determine the water removal characteristics of some commonly used paper machine felts. The structural features analyzed include porosity; specific pore-yarn interfacial surface area; 3D pore size distribution; 3D fiber or yarn-size distribution; and their variations through the thickness direction. The top, middle, and bottom layers of the felt have very different structures to assist with water removal and impart paper properties. The size distribution of the yarns, as well as the pores in the different layers of the felt, are also inherently different. These structural features were non-intrusively quantified. In addition, variation in the structural characteristics through the thickness of the felts and its potential role in papermaking is explored. In addition to the 3D structural characteristics, permeability characteristics and water removal characteristics, including rewetting of select felt samples, have also been experimentally determined. It is interesting to observe the relationship between key structural features and permeability and water removal characteristics. These relationships can provide additional insights into press felt design, as well as ways to improve product properties and the dewatering efficiency and productivity of the paper machine.

Enhanced Oxygen Evolution Reaction by Efficient Bubble Dynamics of Aligned Nonoxidized Graphene Aerogels

Achieving abundant active sites in catalysts by fabricating three-dimensional (3D) microstructures is an efficient approach for improving their oxygen evolution reaction (OER) activities. However, the generated oxygen bubbles in the electrodes are confined in the complex 3D structure, diminishing the catalytic activities and mechanical stability of the electrodes. Therefore, it is essential to rationally design an electrocatalytically active 3D electrode with an optimal microstructure to efficiently remove generated bubbles. Here, we report the fabrication of copper oxide nanoparticles embedded in nonoxidized graphene aerogels (CuONP-NOGAs). The microstructure of CuONP-NOGAs is finely tuned by optimizing the processing parameters of bidirectional freeze casting and its influence on bubble removal behavior efficiency is elucidated. Among electrodes with different degrees of alignment and pore densities, the vertically aligned NOGA with dense porosity exhibits the best efficiency by forming direct open paths for facile bubble movements. The high electrical conductivity combined with a low transfer resistance and uniformly dispersed active particles in CuONP-NOGAs offers excellent OER activities. They deliver a remarkable potential of 1.39 V at 10 mA/cm2, which is lower than those of the state-of-the-art RuO2 and other copper oxide-based catalysts, as well as ultralong stability of more than 120 h, proving the significance of the effective design of the 3D catalyst microstructure. The present study may provide insights into the design of new 3D microstructures useful for practical application in next-generation energy conversion devices.

Biofilm and its implications postfracture fixation: All I need to know.

Biofilm represents an organized multicellular community of bacteria having a complex 3D structure, formed by bacterial cells and their self-produced extracellular matrix. It usually attaches to any foreign body or fixation implant. It acts as a physical protective barrier of the bacteria from the penetration of antibodies, bacteriophages, granulocytes and biocides, antiseptics, and antibiotics. Biofilm-related infections will increase in the near future. This group of surgical site infections is the most difficult to diagnose, to suppress, to eradicate, and in general to manage. Multispecialty teams involved in all stages of care are an effective way to improve results and save resources and time for the benefit of patients and the health system. Significant steps have occurred recently in the prevention and development of clever tools that we can employ in this everlasting fight with the bacteria. Herein, we attempt to describe the nature and role of the "biofilm" to the specific clinical setting of surgical site infections in the field of orthopaedic trauma surgery.

Bioconversion of Guaiacylglycerol-β-guaiacyl ether into vanillin by Burkholderia sp. ISTR5: A genomic and proteomic approach

Long-term research on biofuel production from lignocellulose did not progress much due to strong inter-unit linkages in lignin structure. Lignin contains β-O-4 linkage as a major bond (50–60%) between aromatic compounds to form a complex 3D-structure. The present study aims for the characterization of a novel strain Burkholderia sp. ISTR5 (R5) for β-O-4 linkage disintegration. Guaiacylglycerol-β-guaiacyl ether (GGE) was taken as a representative compound for β-O-4 linkage analysis. We showed that the strain R5 completely degraded GGE in 72 h. Further, gas chromatography-mass spectrometry (GC-MS) profile showed that vanillin is one of the highest produced chemicals during the degradation of GGE with small fractions of other metabolites in the reaction mixture. Nuclear Magnetic Resonance (NMR) analysis demonstrated the fragmentation of β-O-4 bonds and the advent of new chemical bonds. In addition to it, the whole genome analysis showed that R5 contains a superior enzyme chassis for the degradation of aromatic compounds. Enzymes such as glutathione-s-transferase, biphenyl dioxygenase, catalase/peroxidase, hydrolases, and dehydrogenases dominated the genome of R5. Proteomics analysis showed 2 glutathione lyase, 1 glutathione-s-transferase, 1 GMC oxidoreductase, 2 FAD binding oxidoreductase and several hydrolases, peroxidases, and transferases were upregulated on GGE. This study showed the capability of R5 to degrade and bioconvert the β-O-4 linkage lignin model compound GGE into vanillin.

Back to the Future: From Appendage Development Toward Future Human Hair Follicle Neogenesis.

Hair disorders such as alopecia and hirsutism often impact the social and psychological well-being of an individual. This also holds true for patients with severe burns who have lost their hair follicles (HFs). HFs stimulate proper wound healing and prevent scar formation; thus, HF research can benefit numerous patients. Although hair development and hair disorders are intensively studied, human HF development has not been fully elucidated. Research on human fetal material is often subject to restrictions, and thus development, disease, and wound healing studies remain largely dependent on time-consuming and costly animal studies. Although animal experiments have yielded considerable and useful information, it is increasingly recognized that significant differences exist between animal and human skin and that it is important to obtain meaningful human models. Human disease specific models could therefore play a key role in future therapy. To this end, hair organoids or hair-bearing skin-on-chip created from the patient’s own cells can be used. To create such a complex 3D structure, knowledge of hair genesis, i.e., the early developmental process, is indispensable. Thus, uncovering the mechanisms underlying how HF progenitor cells within human fetal skin form hair buds and subsequently HFs is of interest. Organoid studies have shown that nearly all organs can be recapitulated as mini-organs by mimicking embryonic conditions and utilizing the relevant morphogens and extracellular matrix (ECM) proteins. Therefore, knowledge of the cellular and ECM proteins in the skin of human fetuses is critical to understand the evolution of epithelial tissues, including skin appendages. This review aims to provide an overview of our current understanding of the cellular changes occurring during human skin and HF development. We further discuss the potential implementation of this knowledge in establishing a human in vitro model of a full skin substitute containing hair follicles and the subsequent translation to clinical use.

Design of Perfused PTFE Vessel-Like Constructs for In Vitro Applications.

Tissue models mimic the complex 3D structure of human tissues, which allows the study of pathologies and the development of new therapeutic strategies. The introduction of perfusion overcomes the diffusion limitation and enables the formation of larger tissue constructs. Furthermore, it provides the possibility to investigate the effects of hematogenously administered medications. In this study, the applicability of hydrophilic polytetrafluoroethylene (PTFE) membranes as vessel-like constructs for further use in perfused tissue models is evaluated. The presented approach allows the formation of stable and leakproof tubes with a mean diameter of 654.7µm and a wall thickness of 84.2µm. A polydimethylsiloxane (PDMS) chip acts as a perfusion bioreactor and provides sterile conditions. As proof of concept, endothelial cells adhere to the tube's wall, express vascular endothelial cadherin (VE-cadherin) between neighboring cells, and resist perfusion at a shear rate of 0.036Nm-2 for 48h. Furthermore, the endothelial cell layer delays significantly the diffusion of fluorescently labeled molecules into the surrounding collagen matrix and leads to a twofold reduced diffusion velocity. This approach represents a cost-effective alternative to introduce stable vessel-like constructs into tissue models, which allows adapting the surrounding matrix to the tissue properties in vivo.

Atomic Layer Deposition of Electrocatalytic Insulator Al2O3 on Three-Dimensional Printed Nanocarbons.

The advantages of three-dimensional (3D) printing technologies, such as rapid-prototyping and the freedom to customize electrodes in any design, have elevated the benchmark of conventional electrochemical studies. Furthermore, the 3D printed electrodes conveniently accommodate other active layers for diverse applications such as energy storage, catalysis, and sensors. Nevertheless, to enhance a complex 3D structure while preserving the fine morphology, conformal deposition by atomic layer deposition (ALD) technique is a powerful solution. Herein, we present the concept of coating Al2O3 by ALD with different thicknesses from 20 to 120 cycles on the 3D printed nanocarbon/PLA electrodes for the electrocatalytic oxidation of catechol as an important biomarker. Overall, 80 ALD cycle Al2O3 achieved an optimum thickness for catechol electrocatalysis. This is resonated with the enhanced adsorption of catechol at the electrode surface and efficient electron transfer, according to the two-proton, two-electron-transfer mechanism, as well as for the passivation of surface defects of the nanocarbon electrode. This work compellingly demonstrates the prospect of 3D printed electrodes modified by a functional layer utilizing a low-temperature ALD process that can be extended to other arbitrary surfaces.

Formulation of protein‐enriched 3D printable food matrix and evaluation of textural, rheological characteristics, and printing stability

Protein-enriched 3D printing material was formulated by incorporating pea protein isolate (10%) with refined flour as a composite to investigate its suitability for an extrusion-based 3D food printer. The experiment was conducted at compositions viz., composite flour (30–40 g), butter (25–35 g), and water (10–20 g) to identify the best formulation. Central Composite Rotational Design (CCRD) was used to investigate the effect on textural, rheological characteristics, and printable stability of the food matrices. Rheological properties of dough comprising of flow stress, storage modulus (G′), and loss modulus (G″) are used for multiple regression analysis. The best formulated 3D food matrix was selected based on the better printable stability and found to be 30, 30, and 15 g of composite flour, butter, and water, respectively. The hardness, adhesiveness, flow stress, G′, and G″ of the best formulated 3D food matrix were found to be 235.73 N, −944.73 N, 416.55, 23,350, and 6,920 Pa, respectively. Practical applications The work reported in the paper will serve as a potential source for the development of a protein-rich 3D printable food matrix. This is a step forward in the direction of customized nutrition requirements and digital gastronomy. It might be used for the bakery industry, looking for value addition, fortification, and making nutrition-rich cookie, with complex 3D structure. The paper will assist in the selection of the additives which will help in shape retention, good printability, desired textural, and rheological properties. The work reported is based on the extrusion-based 3D food printer which is nowadays used in restaurants, bakeries, and food outlets, so this will be useful for them.

Analysis of Oncogene Protein Structure Using Small World Network Concept

Background: The basic building block of a body is protein which is a complex system whose structure plays a key role in activation, catalysis, messaging and disease states. Therefore, careful investigation of protein structure is necessary for the diagnosis of diseases and for the drug designing. Protein structures are described at their different levels of complexity: primary (chain), secondary (helical), tertiary (3D), and quaternary structure. Analyzing complex 3D structure of protein is a difficult task but it can be analyzed as a network of interconnection between its component, where amino acids are considered as nodes and interconnection between them are edges. Objective: Many literature works have proven that the small world network concept provides many new opportunities to investigate network of biological systems. The objective of this paper is analyzing the protein structure using small world concept. Methods: Protein is analyzed using small world network concept, specifically where extreme condition is having a degree distribution which follows power law. For the correct verification of the proposed approach, dataset of the Oncogene protein structure is analyzed using Python programming. Results: Protein structure is plotted as network of amino acids (Residue Interaction Graph (RIG)) using distance matrix of nodes with given threshold, then various centrality measures (i.e., degree distribution, Degree-Betweenness correlation, and Betweenness-Closeness correlation) are calculated for 1323 nodes and graphs are plotted. Conclusion: Ultimately, it is concluded that there exist hubs with higher centrality degree but less in number, and they are expected to be robust toward harmful effects of mutations with new functions.

Grain size effects in donor doped lead zirconate titanate ceramics

The ferroelectric, ferroelastic, and dielectric properties as well as the crystal structure were investigated for polycrystalline donor doped lead zirconate titanate (PZT) with grain sizes ranging from 0.25 to 5 μm, which were prepared using a novel zirconium titanium hydrate precursor (ZTH) with a specific surface area of 310 m2/g. Piezoforce microscopy was used to investigate the change in the domain structure, revealing a change in the domain configuration from a complex 3D structure to a simple lamellar domain formation at a 1 μm grain size that corresponded to a rapidly increasing internal mechanical stress observed with in situ synchrotron x-ray experiments. The correlation between the change in domain configuration, increasing internal stresses, effects of poling on the crystal structure, and the macroscopic ferroelectric and ferroelastic properties are discussed in detail, allowing a deeper understanding of size effects in polycrystalline donor doped PZT ceramics.

An effective RGB color selection for complex 3D object structure in scene graph systems

The goal of this project is to develop a complete, fully detailed 3D interactive model of the human body and systems in the human body, and allow the user to interacts in 3D with all the elements of that system, to teach students about human anatomy. Some organs, which contain a lot of details about a particular anatomy, need to be accurately and fully described in minute detail, such as the brain, lungs, liver and heart. These organs are need have all the detailed descriptions of the medical information needed to learn how to do surgery on them, and should allow the user to add careful and precise marking to indicate the operative landmarks on the surgery location. Adding so many different items of information is challenging when the area to which the information needs to be attached is very detailed and overlaps with all kinds of other medical information related to the area. Existing methods to tag areas was not allowing us sufficient locations to attach the information to. Our solution combines a variety of tagging methods, which use the marking method by selecting the RGB color area that is drawn in the texture, on the complex 3D object structure. Then, it relies on those RGB color codes to tag IDs and create relational tables that store the related information about the specific areas of the anatomy. With this method of marking, it is possible to use the entire set of color values (R, G, B) to identify a set of anatomic regions, and this also makes it possible to define multiple overlapping regions.

Ceria Nanodots Anchored on ZIF67-Derived Framework By Atomic Layer Deposition for Efficient Bifunctional Oxygen Electrocatalysis

The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), which are the two most important reactions for electrocatalytic activities, has been widely studied for sustainable and renewable electrochemical applications, including fuel cells[1] , [2], metal-air batteries[3] and water electrolysis[4]. For the development of new catalysts alternative to noble metal-based materials, metal organic frameworks (MOFs) are being actively used as the precursor structure. ZIF-67, a kind of MOF structure made of cobalt nitrate and 2-methylimidazole ligands, has proved to be a good candidate for ORR catalysis due to their rich of Co-N-C active sites. However, ZIF-67 tends to aggregate during the pyrolysis process by breaking C-H or C-O bonds.In this study, atomic layer deposition (ALD) was applied to coat an atomically thin cerium oxide (CeO2, ceria) coatings the MOF structure, which is expected to incur synergistic catalytic activity and suppress the thermal agglomeration. ALD is a self-limiting surface chemistry process, and is able to create highly conformally layer-by-layer thin film on any complex 3D structure with controllable thickness at an atomic level.[5] Ceria has shown good synergistic effect with other metals for OER performance due to its ability for electron exchange and ion reduction.[6] We demonstrates a facile synthesis of Co/Ce co-doped porous carbon nanomaterials by pyrolyzing the ceria-coated ZIF structure. The resultant samples showed uniform crystal structure which are in well accordance with ZIF-67 precursors. The as-prepared samples also showed enhanced electrocatalytic activities for both ORR and OER comparable to that of noble metal benchmarks (Pt/C and IrO2) and in terms of onset potential, half-wave potential, and current density. A sample prepared by performing 15 cycles of ceria ALD followed a pyrolysis at 700 °C shows the highest onset potential (0.95 V versus RHE) for ORR and superior stability in comparison to commercialized Pt/C. Meanwhile, a sample with 5 cycles of ceria ALD exhibits an excellent OER performance (1.48 V at 10 mA cm-2) and maintained a good OER durability performance (from 1.48 V to 1.50 V after 2,000 potentiodynamic cycles).

Abstract 14897: Activation Dyssynchrony Between Contact Multielectrode Mapping and Subsurface Near-Infrared Optical Mapping During Human Atrial Fibrillation

Due to complex 3D human atrial structure, atrial fibrillation (AF) mapping with multielectrode arrays (MEA) mostly represents surface activation. Therefore, MEA may not properly visualize patient specific AF mechanisms, which impairs ablation outcomes. Conversely, near-infrared optical mapping (NIOM) visualizes subsurface intramural activation and can efficiently reveal reentrant drivers responsible for AF maintenance. Delay between surface activation seen by MEA electrograms (EGMs) vs subsurface activation seen by NIOM optical action potentials (OAPs) occurs due to dyssynchrony between myocardium layers, especially during AF. Coronary perfused explanted human atria (n=7) were mapped with NIOM (0.3-0.9mm 2 resolution) and 64-electrode MEA (3mm 2 resolution). Unipolar EGMs were analyzed for the steepest negative deflection. The delay between [-dV/dtmax] of unipolar EGMs and corresponding optical action potentials (OAPs) was compared in 500ms and 300ms pacing and AF. Subsequent structural analysis was done by 9.4T MRI (154-180μm 3 resolution) with gadolinium enhancement and histology. Delay between EGM and OAP local activation times rate-dependently and heterogeneously increased from 6±3 ms and 10±4 ms during 500ms and 300ms pacing to 15±11 ms (with maximum delay 47±18 ms) during pacing induced AF (average cycle length 124±65ms). Large local OAP-EGM delay, seen during AF, correlates with higher fibrosis percentage and fiber twist (p<0.05). NIOM identified reentrant drivers maintaining AF, which were incorrectly visualized as multiple breakthroughs in 68% of MEA maps (n=22). Higher frequency leads to an increased activation discrepancy between EGM and NIOM caused by increased dyssynchrony in regions of higher fibrosis percentage and fiber twist, which may prevent MEA from proper identification of AF drivers in diseased fibrotic human atria. Reannotation of EGM activation based on NIOM may be required for correct AF mechanisms visualization.

Color‐Tunable 3D InGaN/GaN Multi‐Quantum‐Well Light‐Emitting‐Diode Based on Microfacet Emission and Programmable Driving Power Supply

AbstractColor‐tunable InGaN/GaN multi‐quantum‐well (MQW) light‐emitting diodes (LEDs) are reported based on GaN microfacet structure directly grown on c‐plane patterned sapphire substrate by metal organic vapor phase epitaxy (MOVPE) through promoting 3D growth. By adjusting GaN growth temperature and pattern arrangement, a GaN microfacet with almost pure {101} semipolar facets is obtained. The multifacetted InGaN/GaN MQW LED chip evolves three distinct emission peaks around 630, 530, and 450 nm in electroluminescence (EL) as injection current increases from 1 to 100 mA. The EL behavior originates from locally different facets of the complex 3D structure: MQWs grown on c‐planes and semipolar facets, respectively, which is confirmed by cathodoluminescence characterization in a scanning transmission electron microscope (STEM‐CL). Considering the dependence of emission wavelength and intensity on injection currents, a programmable power supply is designed to drive the LED. The specific color of the LED is tuned by time‐shared driving of the currents based on three channels with controllable magnitudes and duty cycle from the power supply, covering red, yellow, green, cyan, blue, and purple. Furthermore, white LEDs with high color rendering index (CRI) up to 96.1 and correlated color temperature (CCT) between 4000 and 10 000 K are achieved.

Sex, body size and right atrial volume are the main determinants of tricuspid annulus geometry in healthy volunteers. A 3D echo study using a novel, commercially-available dedicated software package

Abstract Tricuspid annulus (TA) sizing is essential for percutaneous and surgical procedures. Guidelines recommend to assess TA size by 2D echo (2DE) linear dimension; but TA is a complex 3D structure. Aim To identify physiological determinants of TA geometry parameters and their reference values using 3D echo (3DE) and a novel, commercially-available software in healthy volunteers. Methods 254 healthy volunteers (113 men, mean age 47±11 years) were evaluated by 2D and 3DE. 3DE TA analysis was made in 228 of them (feasibility=90%). TA 3DE area, perimeter, diameters, sphericity index and coaptation (Figure) were assessed at mid-systole using a dedicated software package (4D AutoTVQ, GE Healthcare, Horton, N). 3D right atrial (RA) and ventricular (RV) volumes were measured. Results Normal values of 3D TA geometry parameters, RV and RA volumes are presented in table. 3D TA area, perimeter and diameters correlated with BSA (r=0.33 to 0.5, p<0.001) and were larger in men, independently of BSA (p<0.0001). There were no age-related changes in TA parameters (r<0.25, p=0.0001). 2D TA diameters measured in apical 4ch and RV focused views were significantly smaller than 3DE 4ch diameter (16±2 and 16±3 vs 17±3, p<0.0001). RA maximal volumes had the strongest correlation with 3D TA area (r=0.65), compared with RV end-diastolic (r=0.55) and end-systolic (r=0.51) volumes (p<0.0001). By multivariable linear regression, RA maximal volume, sex and BSA, but not RV volumes, were independent predictors of 3D TA area (R2=0.46, p<0.0001). Conclusions Reference values for TA metrics should be sex-specific and indexed to BSA. 2DE underestimates TA dimensions. Even if both RA and RV volumes correlate significantly with TA area, only RA maximum volume was an independent predictor of its size at mid-systole. 3D tricuspid annulus parameters Funding Acknowledgement Type of funding source: None

Radiative-transfer modeling of supernovae in the nebular-phase

Supernova (SN) explosions play a pivotal role in the chemical evolution of the Universe and the origin of life through the metals they release. Nebular phase spectroscopy constrains such metal yields, for example through forbidden line emission associated with O I, Ca II, Fe II, or Fe III. Fluid instabilities during the explosion produce a complex 3D ejecta structure, with considerable macroscopic, but no microscopic, mixing of elements. This structure sets a formidable challenge for detailed nonlocal thermodynamic equilibrium radiative transfer modeling, which is generally limited to 1D in grid-based codes. Here, we present a novel and simple method that allows for macroscopic mixing without any microscopic mixing, thereby capturing the essence of mixing in SN explosions. With this new technique, the macroscopically mixed ejecta are built by shuffling the shells from the unmixed coasting ejecta in mass space, or equivalently in velocity space. The method requires no change to the radiative transfer, but it necessitates high spatial resolution to resolve the rapid variation in composition with depth inherent to this shuffled-shell structure. We show the results for a few radiative-transfer simulations for a Type II SN explosion from a 15 M⊙ progenitor star. Our simulations capture the strong variations in temperature or ionization between the various shells that are rich in H, He, O, or Si. Because of nonlocal energy deposition, γ rays permeate through an extended region of the ejecta, making the details of the shell arrangement unimportant. The greater physical consistency of the method delivers spectral properties at nebular times that are more reliable, in particular in terms of individual emission line strengths, which may serve to constrain the SN yields as well as the progenitor mass for core collapse SNe. The method works for all SN types.

3차원 마이크로 세포칩 제작을 위한 3차원 연속 레이저 스캐닝 방법

Nanostereolithography induced by a femtosecond laser is widely used for fabrication of three-dimensional (3D) microstructures with submicron resolutions. In this study, we propose a 3D continuous laser scanning method for an effective direct writing of 3D microstructures. The advantages of the 3D continuous laser scanning method are analyzed by considering its high resolution, time economy, and fabrication effectiveness. As the 3D continuous laser scanning is an efficient manufacturing method, which can immediately respond to a complex 3D structure, it could be used for various applications including platforms for cell culture, metamaterials, and functional sensors. In this paper, the 3D open cell structure was fabricated and cells are cultured on the structure for microcell chip application.