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The purpose of this study is to understand the effect of ground conditions on microbial cementation in cohesionless soils. Since the method of microbial cementation is still at the experimental stage, for its practical use in the field, a number of laboratory experiments are required for the quantification of microbial cementation under various ground conditions, such as relative densities, relative compactions and particle size distributions. In this study, in order to evaluate the effectiveness of microbial cementation in treated sands and silts, an experiment was performed for different relative densities of silica sands, for different relative compactions of silts and for different particle size distributions of weathered soils sampled from the field. Scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) spectroscopy and mapping analyses were implemented for the quantification of the levels of microbial cementations for sand, silt and weathered soil specimens. Based on the test results, a considerable microbial cementation was estimated depending on the soil conditions; therefore, an implementation of this new type of bio-grouting on a weak foundation may be possible to increase the strength and stiffness of weak ground.

The objective of this study is to investigate the effect of mechanical vibration stimulation on the muscle force and muscle reaction time of lower leg according to perception threshold and vibration frequency. A vibration stimulation with perception threshold intensity was applied on the Achilles tendon and tibialis anterior tendon. EMG measurement and analysis system were used to analyze the change of muscle force and muscle reaction time according to perception threshold and vibration frequency. A root-mean-square (RMS) value was extracted using analysis software and Maximum Voluntary Contraction (MVC) and Premotor Time (PMT) were analyzed. The measurement results showed that perception threshold was different from application sites of vibration frequency. Also, the muscle force and muscle reaction time showed difference according to the presence of vibration, frequency, and intensity. This result means that the vibration stimulation causes the change on the muscle force and muscle reaction time and affects the muscles of lower leg by the characteristics of vibration stimulation.

A soil temperature estimation model for increasing depth in a permafrost area in Alaska near the Bering Sea is proposed based on a thermal response concept. Thermal response is a measure of the internal physical heat transfer of soil due to transferred heat into the soil. Soil temperature data at different depths from late spring to the early autumn period at multiple permafrost sites were collected using automatic sensor measurements. From the analysis results, a model was established based on the relationship between the normalized cumulative soil temperatures (CRCST*i,m and CST*ud,m) of two different depths. CST*ud,m is the parameter of the soil temperature measurement at a depth of 5 cm, and CRCST*i,m is the parameter of the soil temperature measured at deeper depths of i cm (i = 10, 15, 20, and 30). Additionally, the fitting parameters of the mathematical models of the CRCST*i,m–CST*ud,m relationship were determined. The measured soil temperature depth profiles at a different site were compared with their predicted soil temperatures using the developed model for the model validation purpose. Consequently, the predicted soil temperatures at different soil depths using the soil temperature measurement of the uppermost depth (5 cm) were in good agreement with the measured results.

In many layer-structured materials, constituent layers are bound through van der Waals (vdW) interactions. However, hydrogen bonding is another type of weak interaction which can contribute to the formation of multi-layered materials. In this work, we investigate aluminum hydroxide [Al(OH) 3 ] having hydrogen bonding as an interlayer binding mechanism. We study the crystal structures and electronic band structures of bulk, single-layer, and multi-layer Al(OH) 3 using density functional theory calculations. We find that hydrogen bonds across the constituent layers indeed give rise to interlayer binding stronger than vdW interactions, and a reduction of the band gap occurs for an isolated layer as compared to bulk Al(OH) 3 which is attributed to the emergence of surface states. We also consider the alkali-halide intercalation between layers and examine how the intercalated atoms affect the atomic and electronic structures of Al(OH) 3 .

This paper presents an efficient coil design for a mm-sized micro-robot which generates a propulsion force and torque and receives electrical energy using a wireless power transfer system. To determine the most efficient coil structures and produce propulsion and torque on the micro-robot, both helical and spiral coil modeling was conducted, and analytical formulations of the propulsion force and torque were derived for helical and spiral coil structures. Additionally, the dominant dimensional factors for determining propulsion and coil torque were analyzed in detail. Based on the results, an optimum coil structure for generating maximum force on the micro-robot was developed and is herein presented with dimensional analysis. Simulations and experiments were also conducted to verify the design, and good agreement was achieved. A 3-mm micro-robot that simultaneously generated a propulsion force and torque and received electrical energy via wireless power transfer was successfully fabricated using the proposed method and verified.

This paper proposes an autonomous coil alignment system (ACAS) for electric vehicles (EVs) with dynamic wireless charging (DWC) to mitigate the reduction in received power caused by lateral misalignment between the source and load coils. The key component of the ACAS is a novel sensor coil design, which can detect the load coil’s left or right position relative to the source coil by observing the change in voltage phase. This allows the lateral misalignment to be estimated through the wireless power transfer (WPT) system alone, which is a novel tracking method for vehicular applications. Once misalignment is detected, the vehicle’s lateral position is self-adjusted by an autonomous steering function. The feasibility of the overall operation of the ACAS was verified through simulation and experiments. In addition, an analysis based on experimental results was conducted, demonstrating that 26% more energy can be transferred during DWC with the ACAS, just by keeping the vehicle’s load coil aligned with the source coil.

This paper describes the finite element (FE)-based design of a slotted tubular permanent magnet actuator (TPMA) used in railway vehicle active lateral secondary suspension that improves the actuator’s thrust and lowers its cogging force under thermal and geometric constraints. To consider the electromagnetic and thermal fields and the complex interactions among the design variables, design was carried out in an electromagnet and thermal field environment using accurate and time-effective FE analysis. A six-slot prototype model was fabricated to estimate critical thermal parameters, which are difficult to compute without experiments. Three-dimensional FE analysis using the determined thermal parameters was adopted to calculate the precise thermal distribution of the TPMA and verify the forced air-cooling effect. A prototype TPMA with a quasi-Halbach array of permanent magnets and a moving magnet was manufactured through the FE-based design process; the dynamic, electromagnetic, and thermal characteristics of the prototype TPMA were validated experimentally.

Multivalency of targeting ligands provides significantly increased binding strength towards their molecular targets. Here, we report the development of a novel heptameric targeting system, with general applications, constructed by fusing a target-binding domain with the heptamerization domain of the Archaeal RNA binding protein Sm1 through a flexible hinge peptide. The previously reported affibody molecules against EGFR and HER2, Z(EGFR) and Z(HER2), were used as target binding moieties. The fusion molecules were highly expressed in E. coli as soluble proteins and efficiently self-assembled into multimeric targeting ligands with the heptamer as the predominant form. We demonstrated that the heptameric molecules were resistant to protease-mediated digestion or heat- and SDS-induced denaturation. Surface plasmon resonance (SPR) analysis showed that both heptameric Z(EGFR) and Z(HER2) ligands have a significantly enhanced binding strength to their target receptors with a nearly 100 to 1000 fold increase relative to the monomeric ligands. Cellular binding assays showed that heptameric ligands maintained their target-binding specificities similar to the monomeric forms towards their respective receptor. The non-toxic property of each heptameric ligand was demonstrated by the cell proliferation assay. In general,, the heptamerization strategy we describe here could be applied to the facile and efficient engineering of other protein domain- or short peptide-based affinity molecules to acquire significantly improved target-binding strengths with potential applications in the targeted delivery of various imaging or therapeutic agents..

In our previous experiments, it was shown that odors (rose, sandalwood) might influence the haptic perception (stiffness, roughness). In particular, subjects felt a smooth surface even smoother with rose odor and a stiff surface even harder with sandalwood odor. This study investigated whether the effects of odors could be explained by their categories that are derived from the verbal descriptions of odors. We used jasmine that is categorized as “flower”, which includes rose, and peppermint that is categorized as “herb” close to sandalwood for our experiments. Subjects were requested to adjust the roughness or stiffness of a test surface to match that of a standard surface just shown before it using a force-feedback device. Standard surfaces were presented with different odors (jasmine, peppermint, odorless) which was projected to the noses of subjects. The results showed that jasmine made subjects feel the surfaces softer than those in odorless condition, but had no effect on roughness perception. Meanwhile peppermint did not show significant effect on either stiffness or roughness perception. According to the inconsistency between the results of present and previous experiments, we argue that odors in similar categories do not necessarily influence haptic perception in the same way.

Background/Aim: Inflammatory bowel disease (IBD) is characterized by dysregulated immune responses and a multifactorial etiology. While imatinib has demonstrated efficacy in the treatment of immune-related diseases, its potential effects in IBD treatment remain underexplored. Materials and Methods: This study aimed to investigate the therapeutic effects of imatinib in colitis treatment. A dextran sulfate sodium (DSS)-induced colitis model was used to mimic IBD in mice. Imatinib was administered orally to mice simultaneously with DSS treatment. The effects of imatinib on DSS-induced colitis were evaluated by analyzing colitis-related pathology, including the disease activity index (DAI), histological lesions, inflammatory markers, and tight junction integrity. Additionally, western blot analysis and quantitative real-time polymerase chain reaction were used to assess inflammatory markers, tight-junction proteins, and cell death. Results: In the DSS-induced colitis model, imatinib treatment exerted protective effects by attenuating weight loss, restoring colon length, reducing spleen weight, and improving the DAI score and histological lesions. Additionally, imatinib reduced the level of proinflammatory cytokines, including TNF- α, IL-6, and IL-1β. Furthermore, imatinib treatment restored tight-junction integrity and decreased the expression of apoptosis marker proteins. Conclusion: Overall, imatinib treatment significantly alleviated the symptoms of DSS-induced colitis by influencing the expression of proinflammatory cytokines, tight junction proteins, and apoptotic markers in mice. These findings highlight imatinib as a potential therapeutic candidate for IBD. [ABSTRACT FROM AUTHOR]

The objective of this study was to find variables that showed significant associations with cognitive decline and memory loss in visual, auditory, olfactory, and balance functions. Seventysix elderly people aged 65 or older participated in the experiment, received the aforementioned functions' assessments, and underwent cognitive screening. Participants were divided into the normal cognitive (NC) and lower cognitive (LC) groups on the basis of cognitive function test scores, and the LC group was divided into the lower-MIS and normal-MIS groups on the basis of memory index scores (MISs). The LC group had less balance, hearing, and olfactory functions than the NC group, and the lower-MIS group had less visual and auditory functions than the normal-MIS group. The performance of the classification model made of variables was evaluated as the area under the receiver operating characteristic curve. The performance was shown to be good. Therefore, this study can be the basis for the development of tools for the early diagnosis of dementia and the creation of a smart environment. [ABSTRACT FROM AUTHOR]

Obtaining quantitative information for molecular species present in aerosols from real-time mass spectrometers such as an extractive electrospray time-of-flight mass spectrometer (EESI) and an aerosol mass spectrometer (AMS) can be challenging. Typically, molecular species are calibrated directly through the use of pure standards. However, in some cases (e.g., secondary organic aerosol (SOA) formed from volatile organic compounds (VOCs)), direct calibrations are impossible, as many SOA species can either not be purchased as pure standards or have ambiguous molecular identities. In some cases, bulk OA sensitivities are used to estimate molecular sensitivities. This approach is not sufficient for EESI, which measures molecular components of OA, because different species can have sensitivities that vary by a factor of more than 30. Here, we introduce a method to obtain EESI calibration factors when standards are not available, and we provide a thorough analysis of the feasibility, performance, and limitations of this new technique. In this method, complex aerosol mixtures were separated with high-performance liquid chromatography (HPLC) followed by aerosol formation via atomization. The separated aerosols were then measured by an EESI and an AMS, which allowed us to obtain sensitivities for some species present in standard and SOA mixtures. Pure compounds were used to test the method and characterize its uncertainties, and obtained sensitivities were consistent within ±20% when comparing direct calibrations vs. HPLC calibrations for a pure standard and within a factor of 2 for a standard mixture. In some cases, species were not completely resolved by chromatography, and positive matrix factorization (PMF) of AMS data enabled further separation. This method should be applicable to other real-time MS techniques. Improvements in chromatography are possible that would allow better separation in complex mixtures. [ABSTRACT FROM AUTHOR]