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Currently, high-rise buildings are being continuously constructed, and thus, it is necessary to predict evacuation safety in advance in case of emergency situations in high-rise buildings. However, current studies focus only on the movement of individuals in evacuation situations for predicting the final evacuation time. Therefore, in this study, a simulation of realistic evacuation in high-rise buildings was performed based on characteristics such as the physical stamina of evacuees. The evacuation simulation was performed on the world's tallest high-rise building, Burj Khalifa, and comparative verification was performed with and without consideration of the physical stamina of evacuees. The results of the simulation indicated that the total evacuation time significantly increases when physical stamina is considered. Hence, realistic evacuation in high-rise buildings is possible when the stamina of evacuees is considered.

Hypoxia is considered an important factor in the proliferation and stemness of mesenchymal stem cells (MSCs). This study aimed to obtain large numbers of mouse clonal MSCs (mc-MSCs) and evaluate the effect of hypoxia on the proliferation and differentiation of mc-MSCs. mc-MSCs were cultured on a Cytodex 3 microcarrier in a spinner flask for a suspension culture to increase mass productivity. To produce the hypoxic conditions, CoCl2 and Na2SO3 were used in a low glucose DMEM medium. The hypoxia environment was established using 0.5g/L Na2SO3 with 10μM or 100 µM CoCl2 for 24 hours. As a result, the proliferation of mc-MSCs under hypoxic conditions was 1.56 times faster than the control group over seven days. The gene expression of HIF-1a and VEGFA increased 4.62 fold and 2.07 fold, respectively. Furthermore, the gene expression of ALP, RUNX2, COL1A, and osteocalcin increased significantly by 9.55, 1.55, 2.29, and 2.53 times, respectively. In contrast, the expression of adipogenic differentiation markers, such as PPAR-γ and FABP4, decreased. These results show that the hypoxia environment produced by these chemicals in a suspension culture increases the proliferation of mc-MSCs and promotes the osteogenic differentiation of mc-MSCs.

Although immunotherapy holds promising cytotoxic activity against lymphoma or leukemia, the immunosuppressive mechanisms of solid tumors remain challenging. In this study, we developed and applied a hypergravity exposure system as a novel strategy to improve the responsiveness of breast cancer cells to natural killer (NK) cells for efficient immunotherapy. Following exposure to hypergravity, either in the presence or absence of NK cells, we investigated for changes in the cell cytoskeletal structure, which is related to the F-actin mediated immune evasion mechanism (referred to as “actin response”) of cancer cells. Breast cancer cell line MDA-MB-231 cells were exposed thrice to a 20 min hypergravitational condition (10 × g), with a 20 min rest period between each exposure. The applied hypergravity induces changes in the intracellular cytoskeleton structure without decreasing the cell viability but increasing the cytotoxicity of MDA-MB-231 from 4 to 18% (4.5-fold) at a 3:1 ratio (NK-to-target). Analyses related to F-actin further demonstrate that the applied hypergravity results in rearrangement of the cytoskeleton, leading to inhibition of the actin response of MDA-MB-231. Taken together, our results suggest that the mechanical load increases through application of hypergravity, which potentially improves efficiency of cell-based immunotherapies by sensitizing tumors to immune cell-mediated cytotoxicity.

Boundary representation (B-rep) is one of the most common techniques for representing three-dimensional (3D) shapes. In this method, shapes are described mathematically based on the vertices, edges, and faces present. B-rep models are generated using computer-aided design systems and are employed for various purposes in downstream applications, including computer-aided engineering, manufacturing, and inspection. Therefore, the level of detail of the 3D model should be adjusted based on the purpose of use. In this study, we performed multiobjective optimization for the feature-based simplification of B-rep models. The two objectives of the general model simplification process are to minimize the data size and limit the differences in appearance with respect to the original model. To simultaneously meet these objectives, model simplification was performed to minimize both the difference in the volume and the number of faces with respect to those of the original model. For optimization, we used the simple genetic algorithm (SGA) and the non-dominated sorting genetic algorithm II (NSGA-II). The experimental results confirmed that solution set obtained using NSGA-II was of higher quality as compared with those for SGA and the conventional method.

Feature-based translation of computer-aided design (CAD) models allows designers to preserve the modeling history as a series of modeling operations. Modeling operations or features contain information that is required to modify CAD models to create different variants. Conventional formats, including the standard for the exchange of product model data or the initial graphics exchange specification, cannot preserve design intent and only geometric models can be exchanged. As a result, it is not possible to modify these models after their exchange. Macro-parametric approach (MPA) is a method for exchanging feature-based CAD models among heterogeneous CAD systems. TransCAD, a CAD system for inter-CAD translation, is based on this approach. Translators based on MPA were implemented and tested for exchange between two commercial CAD systems. The issues found during the test rallies are reported and analyzed in this work. MPA can be further extended to remaining features and constraints for exchange between commercial CAD systems.

In industrial plants, an increasing need has emerged for visualization through three-dimensional (3D) models throughout all lifecycle stages. Lightweight modeling has garnered attention for improved visualization performance. The data size of an entire process plant model is enormous, and the final model consists of various forms of equipment and material model generated from diverse sources. We propose an adaptable method to simplify models with various semantics during the lifecycle of plants. The characteristics of plant equipment and materials are analyzed to define the semantics criteria, upon which the level of semantics (LOS) is defined. The functional requirements of model lightweighting in the plant industry are organized, and comprehensive lightweighting procedures for each stage satisfying those requirements are established. The proposed lightweighting procedures can be applied adaptively to the LOS of each model. We develop a prototype system to demonstrate the proposed method. We conducted simplification experiments for two assembly models with completely different LOS. Two models were simplified gradually and effectively by the proposed simplification procedures, and the data size of each model was reduced by 99 % and 83 %.

Mechanical vibration is a key external stimulus of living organisms. In previous studies, mechanical vibration has been found to affect the proliferation and differentiation of cells. However, there have been few reports of similar effects at the organismal scale. In this study, we demonstrated the effect of mechanical vibration on the growth and activity of Caenorhabditis elegans in the embryonic stage. The group of worms that were exposed to mechanical vibration during the embryonic period grew faster than the control group of worms. The growth of all groups was compared by measuring body length. Furthermore, we investigated the mechanical vibration effects in two types of mutants: body wall mechanosensory-abnormal mutants (mec-4(e1339)) and head mechanosensory-defective mutants (trp-4(sy695)). The mec-4(e1339) mutant was not affected by mechanical vibration during growth. On the other hand, the trp-4(sy695) mutant exposed to mechanical vibration showed a difference in growth compared with the control group, similar to wild-type worms. Therefore, mechanical vibration during the early developmental period of C. elegans affects the growth and activity of worms. Additionally, we observed a relationship between the gastrulation period and the mechanosensory system development of the worms. This study will serve as the basis for analyzing the effects of mechanical vibration on the developmental stages of C. elegans.

To evaluate the environmental performance of manufacturing systems, practitioners often deploy ad-hoc methods or implement one-off solutions that are difficult to replicate in similar scenarios. Such situations can drive-up costs and cause significant delays. Hence, there is a strong need for standard methods that help describe and replicate environmental performance evaluation (EPE) processes. In response, ISO 20140 provides guidelines for converting and aggregating environmental performance evaluation data. This paper provides an overview of ISO 20140, and showcases the usefulness of ISO 20140 by describing and analyzing the usage view of the EPE process. The analysis is conducted with an evaluation experiment about the machining of a mill-tern part, in which energy consumption of a variety of process modes such as active machining, tools change, rapid traverse, and pausing, are evaluated. The experiment is jointly conducted by National Institute of Standards and Technology in the United States and the National Institute of Advanced Industrial Science and Technology in Japan.

ontostep is a method to translate the STandard for the Exchange of Product Model Data (STEP) schema and its instances to an ontology and knowledge graphs represented in the web ontology language (owl). ontostep models can be integrated with any owl models to enrich their semantics. However, the current implementation has several limitations, mainly in (1) supporting the latest International Organization for Standardization (ISO) 10303 schemas and (2) generating various representation types depending on the purpose of use. We present an improved implementation of ontostep to overcome these limitations. In this article, we demonstrate that the new implementation can successfully translate STEP schemas and instances in a faster and more flexible way, thus furthering the adoption of the full capabilities of ISO 10303. By encoding STEP entities in owl, we facilitate integration with other standards through knowledge graphs.

Local anesthesia is a drug that penetrates the nerve cell membrane and binds to the voltage gate sodium channel, inhibiting the membrane potential and neurotransmission. It is mainly used in clinical uses to address the pain of surgical procedures in the local area. Local anesthetics (LAs), however, can be incorporated into the membrane, reducing the thermal stability of the membrane as well as altering membrane properties such as fluidity, permeability, and lipid packing order. The effects of LAs on the membrane are not yet fully understood, despite a number of previous studies. In particular, it is necessary to analyze which is the more dominant factor, the membrane affinity or the structural perturbation of the membrane. To analyze the effects of LAs on the cell membrane and compare the results with those from model membranes, morphological analysis and 50% inhibitory concentration (IC50) measurement of CCD-1064sk (fibroblast, human skin) membranes were carried out for lidocaine (LDC) and tetracaine (TTC), the most popular LAs in clinical use. Furthermore, the membrane affinity of the LAs was quantitatively analyzed using a colorimetric polydiacetylene assay, where the color shift represents their distribution in the membrane. Further, to confirm the membrane affinity and structural effects of the membranes, we performed an electrophysiological study using a model protein (gramicidin A, gA) and measured the channel lifetime of the model protein on the free-standing lipid bilayer according to the concentration of each LA. Our results show that when LAs interact with cell membranes, membrane affinity is a more dominant factor than steric or conformational effects of the membrane.

Recently, the importance of inhalation toxicity assessment increased due to recent humidifier disinfectant-associated deaths in children. Benzalkonium chloride (BAC) is currently used as a cationic surfactant and germicide in food industry processing lines and as a hand sanitizer. Animal models are mainly used as a method of evaluating the inhalation toxicity of a hazardous substance, but that approach requires considerable amounts of time and cost. As a replacement for animal experiments, in vitro cell culture can be used to assess toxicity. However, such culture does not reflect the natural microenvironment of the lung, particularly its dynamic nature. In this study, we simulated normal breathing levels (tidal volume 10%, 0.2 Hz) through surface elongation of an elastic membrane in a dynamic culture system. The low-cost dynamic system provided easy control of breathing rate during lung cell culture. We assessed the toxicity using different concentrations of BAC (0, 2, 5, 10, 20, and 40 μg/mL) under static and dynamic culture conditions. Following 24 h of exposure to BAC, cellular metabolic activity, cell membrane integrity, interleukin-8 (IL-8) and reactive oxygen species (ROS) levels, and the total amount of protein in cells were analyzed. Our results showed that significant differences in cellular metabolic activity, as well as IL-8 and ROS profiles, between static and dynamic cell growth conditions, following BAC exposure.

A model simplification technique is required to control the level of detail (LOD) of a three-dimensional (3D) computer-aided design (CAD) model. In particular, to simplify a B-rep model, volume decomposition operations are performed to decompose the model into volumes, and the decomposed volumes are then sequentially removed according to their importance. Volume decomposition operations can be categorized into wrapping and cutting decompositions, depending on the type of the acquired delta volume. If both wrapping and cutting decompositions can be applied to the same region, a criterion should be established for selecting the appropriate operation for that region. In this paper, we propose selective and iterative volume decomposition that combines four wrapping and two cutting decomposition operations. In addition, we propose volume and area ratios as the selection criteria for wrapping and cutting. We conducted experiments involving two part models and two assembly models to validate the proposed method. The experimental results showed that the proposed method produces a larger number of decomposed volumes with various volume distributions compared to previous methods. In summary, the proposed method is a highly effective approach for achieving incremental model simplification and obtaining multi-resolution models.

Diabetes mellitus is a chronic, progressive disease that has lasting effects on several organs and tissues. In addition, high glucose levels, high triglyceride and high cholesterol levels increase patient health problems. In this study, we investigated natural materials that can alleviate diabetes symptoms or prevent its onset and assessed extracts of bamboo stem, which has been known for centuries as a functional food. Mouse 3T3-L1 cells were induced to differentiate by adding a mixture of dexamethasone, 3-isobutyl-1-methylxanthine, and insulin (DMI) to the cell media after cells reached 100% confluence. The cells were then treated with hot water extract (HE), ethanol extract (EE), or methanol extract (ME) of bamboo stem for 4 and 13 days, after which the expression levels of differentiation markers C/EBPβ, PPARγ, and FABP4 were measured. At day 13, changes in metabolic function were assessed by analyzing the expression levels of ABCG1, CD36, and GLUT4 using RT-qPCR. Adipocyte size distribution was determined using a Coulter counter after trypsinization. The total triglyceride content was quantified using an adipogenesis assay kit. The HE-, EE-, and ME-treated 3T3-L1 cells showed increased adipogenesis marker expression, triglyceride content, and adipocyte volumes compared to the controls. The expression of genes related to adipocyte function were elevated in EE- and ME-treated samples. Taken together, these findings indicate that bamboo stem extracts, especially ethanol extract, have prophylactic effects for diabetes that occur through the promotion of adipogenesis and adipocyte functions.

Integrating environmental sustainability assessment into parametric design presents an opportunity for enabling sustainable product design. However, this is a challenging task as quantitative methods for sustainability assessment are poorly integrated with parametric design and optimization tools. Furthermore, current streamlined approaches for computing environmental impact during the design stage often ignore manufacturing-related impacts resulting from the geometric complexity of parts. To address these gaps, we present a systematic workflow for computing environmental indicators from parametric design models. Our workflow utilizes the unit manufacturing process information model to evaluate manufacturing-phase resource consumption from process planning data, and consequently enables quantitative correlation of design parameters to the calculated environmental indicators. We demonstrate our workflow through a case study involving the design of a rigid flange coupling, wherein we evaluate the influence of geometric design parameters on the corresponding environmental impact of the design.

Computer-aided design, engineering, and manufacturing (CAx) have improved product design and development. The associativity of revised design in native files for downstream applications, assembly design, finite element analysis, and numerical control (NC) manufacturing has been supported by homogeneous CAx systems. However, heterogeneous CAx environments have issues when neutral models are revised and re-imported because the required identification information is missing. This results in a problem of the associativity of neutral models. In this study, different computer-aided design (CAD) applications have been analyzed with respect to their capabilities for import and export of neutral models with identification information. A tool has been selected to demonstrate the key findings. Moreover, future directions have been discussed to solve associativity issues in design re-import based on neutral models.

In a nuclear power plant, classification is a key tool to manage equipment and materials. There could be different classifications corresponding to the different lifecycle phases and the challenge is to achieve and maintain interoperability, continuity, traceability between them. Therefore, it is important to define the equipment and materials classification based on standardized information models in order to effectively share and integrate lifecycle data of equipment and materials. To accomplish this, a method for standardized exchange of plant equipment and materials data based on ISO 15926 methodology in nuclear power plants is suggested. In the proposed method, we use an information model to expand the equipment and materials classification used for the operation and maintenance phase of a nuclear power plant. This is based on the ISO 15926 standard after analyzing the master data from the Shin Kori unit 1 and 2 of Korea Hydro & Nuclear Power Co., Ltd. (KHNP). Furthermore, as a data exchange tool in the proposed method, this study develops a method to exchange equipment and materials specification data by using iRINGTools.