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Positioning in indoor environments, where it is difficult to achieve an accurate performance using GPS or satellites, has been studied in various ways using several wireless communication systems. Recently, interest in indoor positioning technology for smart environments has increased owing to a wide range of services provided by the IoT and ubiquitous connections. Among these, the passive positioning system is a method for estimating the position of an object without a physical receiver operating on its own power. Representative passive positioning systems include passive radio frequency identification (RFID) and shadow-based passive visible light positioning (VLP) systems. However, RFID is primarily applied to ultrashort-range information recognition services, and shadow-based systems can only recognize approximate shadows owing to interference from the surroundings. Therefore, we propose a passive VLP method that can effectively solve these problems in an indoor positioning system (IPS) using spherical reflectors. We first analyzed the signal intensity attenuation represented by the signal characteristics of specular reflection and defined a mathematical model of the passive VLP system. We propose a new positioning method that can effectively estimate the target position by significantly reducing the target position candidates. To verify the proposed method, a passive VLP system was implemented in an experimental environment. The proposed method achieved an average positioning error of 7.6 cm using convex mirror reflectors with a diameter of 5 cm in a positioning area of $0.4\times0.25$ m with a height of 1.7 m.

Weissella (W.) cibariastrain Chonnam Medical University (CMU) has shown oral colonizing ability and inhibitory effects on the formation of volatile sulfur compounds (VSCs) in vitrostudies. The present study was conducted to analyze the effects of the W. cibariaCMU on canine oral health. Halitosis, calculus, plaque, gingivitis, and intraoral microbiota were assessed in 3 groups: control (maltodextrin), W. cibariaCMU low concentration (CMU-L, 2 × 107colony forming unit [CFU]), and high-concentration (CMU-H, 2 × 109CFU). Halitosis was analyzed using both organoleptic evaluation and measurement of VSCs. Intraoral microbiota were analyzed by real-time polymerase chain reaction. From week 4, the total VSC level in the CMU-H group (4.0 ± 1.30 ng/10 mL) was significantly lower than in the control group (6.3 ± 2.28 ng/10 mL). Significant reduction in methyl mercaptan in the CMU-treated groups was also observed. In addition, the plaque index in the CMU-treated groups was significantly decreased. The CMU-treated groups showed significant decreases in Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythiaand demonstrated the colonizing ability of W. cibariaCMU in the oral cavity. We demonstrated that W. cibariaCMU suppresses halitosis, colonizes the oral cavity, and inhibits the proliferation of malodor-causing oral bacteria in beagles. According to these results, we expect that W. cibariaCMU could be a new oral hygiene solution by reducing VSC production and inhibiting the growth of oral harmful bacteria in companion animals.

Thoracic ossification of the ligamentum flavum (TOLF) is a rare pathology for which limited research exists. While it is known that mechanical factors play a role in the development of TOLF, little is currently understood about the sagittal alignment and related mechanical stress involved in its development. This study aims to describe the sagittal alignment of patients with TOLF based on the pathologic evolution of the Roussouly classification. The current study evaluated the preoperative Roussouly type in consecutive patients who underwent posterior decompressive laminectomy with or without posterior screw fixation for TOLF between January 2015 and December 2021. The post-evolution sagittal alignments were analyzed using the classic Roussouly classification based on sacral slope (SS). To determine the pre-evolution Roussouly type, the patients were retrospectively classified using their individual PI and PT values. Lumbopelvic parameters and morphological index including inflection point (IP), lumbar apex (LA), and lordosis distribution index (LDI) were also evaluated. Forty-three patients (21 women and 22 men) were included; their mean age was 64.21 ± 11.01 years (range 43–81). The most affected level was T10-11 (48.83%). The mean PI was 50.81 ± 9.56°, the mean SS was 33.11 ± 8.61°and the mean PT was 17.69 ± 7.89°. According to the post-evolution Roussouly classification, type 2 shape was the most frequently observed type (n = 23, 53.5%) in the post-evolution classification while type 3 was the most common type observed in the pre-evolution classification (n = 22, 51.5% and P = .00). The level of IP and LA in type 3 moved caudally (around L2 and L4/5 level, respectively) and the LDI increased (77.98 ± 8.08%) than the normal standard value. The authors found that the majority of the patients had a false type 2 spine, which had evolved pathologically from Roussouly type 3 and exhibited increased LDI, a lowered level of IP, and a lowered level of LA. These changes of spinal shape, including the transition to long hypolordosis and increased length of the thoracic kyphosis, may have accentuated tensile stress at the lower thoracic spine and contributed to the development of TOLF.

A polycrystalline WSe 2 nanocompound was produced via a brief thermal reaction between the atomic elements. It should grow along the in-plane direction with covalent bonds rather than along the through-plane direction with van der Waals forces, leading to both crystallographic and morphological anisotropies. Not only the anisotropies should structurally induce strong phonon scattering but they alleviate possible electron scattering at the van der Waals forces; thus, we greatly reduced thermal conductivity while minimizing electrical conductivity loss. The decoupled conductivities resulted in enhancement in figure of merit, by approximately 70% at 350 °C, thus affording a promising material for mid-temperature thermoelectric operations. [ABSTRACT FROM AUTHOR]

Retrospective cross-sectional study To evaluate the validity and obtain optimal cutoff values of 3 radiologic measurements for the diagnosis of basilar invagination (BI). Two hundred seventy-six patients (46 patients who underwent atlantoaxial fusion for BI and 230 patients who were treated for minor cervical trauma) seen in a single institution from January 2010 to December 2016 were included in this study. Age, sex, and body mass index were adjusted for the patients. The Ranawat index (RI), modified Ranawat method (MRM), and Redlund-Johnell method (RJM) were used to diagnose BI on plain radiographs. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and diagnostic odds ratio of 3 radiologic measurements were compared. We also calculated the optimized cutoff values of 3 radiologic measurements using the receiver operating characteristic curve in our patients. The mean age of the 130 women and 146 men was 58.3 ± 14.5 years. The mean values of RI, MRM, and RJM in the BI group were 12.5 ± 3.3, 23.1 ± 3.8, and 27.3 ± 3.6 in women and 13.6 ± 2.6, 26.8 ± 4.2, and 34.7 ± 5.1 in men. There was a significant difference between the sexes (P < .05). The accuracies of RI, MRM, and RJM were 95%, 89.6%, and 92.3% in women and 93%, 68.2%, and 85.4% in men, respectively. The optimized cutoff values of RI, MRM, and RJM were 14, 26, and 32 mm in women and 15, 29, and 38 mm in men. Three radiologic measurements (RI, MRM, and RJM) are reliable for the diagnosis of BI even in the era of cross-sectional images. The validity of these measurements depends on sex and particular radiologic measurement. The optimized cutoff values of RI, MRM, and RJM were 14, 26, and 32 mm in women and 15, 29, and 37 mm in men. These cutoff values showed high validity when compared to the CT and MRI findings.

Well-crystallized $BaSi_2O_5:Eu^{2+}$ phosphor films were synthesized by heat treatment of spin-coated BaO:Eu on $SiO_2$ glass. We investigated luminescence-structure properties of these phosphor films as a function of heat-treatment temperature. From x-ray diffraction patterns, our $BaSi_2O_5:Eu^{2+}$ phosphor films revealed that (111)- and (204)-crystal planes of $BaSi_2O_5$ crystal were dominantly increased with an increase of heat-treatment temperature. Photoluminescence intensities of $BaSi_2O_5:Eu^{2+}$ phosphor films were increased with amount of these crystal planes. It can be explained that $Eu^{2+}$ ions were stably occupied at specific crystal orientation of $BaSi_2O_5$ crystal, enhancing the luminescent intensities of $BaSi_2O_5:Eu^{2+}$ phosphor films. In addition, our $BaSi_2O_5:Eu^{2+}$ phosphor films had transmittance of 70% at 510 nm,.due to the dense morphology and specific crystallinity of $BaSi_2O_5:Eu^{2+}$ phosphor films.

We synthesized ternary n-type bismuth tellurium selenide nanomaterials for thermoelectric applications via a water-based chemical reaction under an atmospheric environment. In this work, bismuth nitrate was employed as a bismuth precursor and was hydrolyzed to form bismuth hydroxide in an aqueous solution. Ascorbic acid was used to dissolve the bismuth hydroxide and give a reactive bismuth source (Bi3+ions) that was able to react with anion sources (Te2–/Se2–ions). Ascorbic acid played a role in reducing bismuth hydroxide to an unreactive bismuth source (bismuth particles, Bi0). We confirmed that ascorbic acid dissolved or reduced bismuth hydroxide depending on the solution pH. Because either Bi3+ions or bismuth particles were generated depending on the pH, the nanomaterial stoichiometry was pH dependent. Nanomaterials prepared at various pH levels were individually sintered using a spark plasma sintering process to measure their thermoelectric transport properties (i.e., carrier concentration, electrical resistivity, Seebeck coefficient, and thermal conductivity). We observed how the transport properties were affected through adjustment of the pH of the reaction and found an appropriate pH for optimizing the transport properties, which resulted in enhancement of the thermoelectric performance.

In current design practice, the shear wave velocity (Vs) of the core and rock-fill zone of a dam, one of the characteristics essential for seismic response design, is seldom determined by field tests. This is because the borehole seismic method is often restricted in application, due to stabilisation activities and concern for the security of the dam structure, and surface wave methods are limited by unfavourable in-situ site conditions. Consequently, seismic response design for a dam may be performed using Vs values that are assumed, or empirically determined. To estimate Vs for the core and rock-fill zone, and to find a reliable method for measuring Vs, seismic surface wave methods have been applied on the crest and sloping surface of the existing ‘M’ dam. Numerical analysis was also performed to verify the applicability of the surface wave method to a rock-fill dam. Through this numerical analysis and comparison with other test results, the applicability of the surface wave method to rock-fill dams was verified.

We reported previously that N‐myc downstream‐regulated gene 2 (NDRG2), a member of a new family of differentiation‐related genes, is expressed specifically in dendritic cells (DC) differentiated from monocytes, CD34+progenitor cells, and the myelomonocytic leukemic cell line. In this study, we demonstrate that NDRG2 protein expression is detected, not only in in vitro‐differentiated DC but also in primary DC from lymph nodes, thymus, and skin when anti‐NDRG2 antibodies are used. As predicted from previous studies investigating the mRNA expression pattern of several types of cell lines, progenitor cells, and DC, NDRG2 protein was expressed strongly in DC. Its expression was detected at significant levels after differentiation from progenitor cells. RNA interference of NDRG2 demonstrated that activated leukocyte cell adhesion molecule (ALCAM) expression is down‐regulated specifically in DC differentiated from NDRG2 small interfering RNA (siRNA)‐transfected monocytes. This was consistent with our observation that U937 cells transfected with NDRG2 became resistant to the GM‐CSF/IL‐4‐induced ALCAM reduction. Furthermore, DC, which had differentiated from NDRG2 siRNA‐transfected monocytes, showed a reduced ability to induce T cell proliferation. Taken together, our results indicate that NDRG2 is able to preserve ALCAM expression during DC differentiation from monocytes under cytokine culture conditions and that its expression helps DC maintain costimulatory signals necessary for T cell stimulation.

AbstractExperimental and analytical studies on the penetration integrity of the reactor vessel have been performed to investigate the potential for reactor vessel failure during a severe accident in the Advanced Power Reactor 1400. Six tests have been performed to analyze the effects of the annulus water between the in-core instrumentation nozzle and the thimble tube, external vessel cooling, in-vessel pressure, melt mass, and melt flow for the maintenance of penetration integrity using alumina (Al2O3) melt as a simulant. The experimental results have been evaluated using the Lower head IntegraLAnalysis computer Code (LILAC) and the Modified Bulk Freezing (MBF) model. The test results have shown that the water inside the annulus is very effective in the maintenance of the reactor vessel’s penetration integrity because the water prevents the melt from ejection through penetration. The penetration in the no external vessel cooling case has more damage than that in the external vessel cooling case. An increase in in-vessel pressure from 1.0 to 1.5 MPa did not create penetration damage, but an increase in melt mass from 40 to 60 kg and melt flow due to the vessel geometry significantly increased the amount of penetration damage. The analytical results using the LILAC computer code and the MBF model are very similar to the experimental results for the ablation depth of the weld and the melt penetration distance through the annulus, respectively.

AbstractExperimental and analytical studies on the thermal behavior of reactor vessel penetration have been performed under external vessel cooling during a severe accident in the Korean next-generation reactor APR1400. Two types of tests, SUS-EXT and SUS-DRY with and without external vessel cooling, respectively, have been performed using sustained heating by an induction heater. Three tests have been carried out varying the cooling conditions at the vessel outer surface in the SUS-EXT tests. The experimental results have been thermally estimated using the LILAC computer code. The experimental results indicate that the inner surface of the vessel was ablated by the 45-mm thickness in the SUS-DRY test. Despite the total ablation of the welding material, the penetration was not ejected outside the vessel, which could be attributed to the thermal expansion of the penetration. Unlike the SUS-DRY test, the thickness of the ablation was ~15 to 20 mm at most, so the welding was preserved in the SUS-EXT tests. It is concluded from the experimental results that the external vessel cooling highly affected the ablation configuration and the thermal behaviors of the vessel and the penetration. An increase in coolant mass flow rate from 0.047 to 0.152 kg/s had effects on the thermal behavior of the lower head vessel and penetration in the SUS-EXT tests. The LILAC analytical results on temperature distribution and ablation depth in the lower head vessel and penetration were very similar to the experimental results.

Here, two important isoflavones present in Trifolium pratense,formononetin and biochanin A, were analyzed by high performance liquid chromatography coupled with UV (HPLC–UV). These isoflavones are marker compounds with anti-inflammatory, anti-cancer, and anti-oxidant properties, and are also potent phytoestrogens that can be used in hormonal therapies. Till date, no study regarding rapid identification and quantification of T. pratenseextract has been conducted. This study developed and validated an optimized method for quantifying formononetin and biochanin A using HPLC–UV. The results showed excellent linearity of the calibration curve (r2≥ 0.999), and good resolutions of chromatographic peaks were obtained. Other validation parameters such as specificity, accuracy, and precision demonstrated that our method had good reliability and sensitivity. Furthermore, our method for quantifying formononetin and biochanin A in T. pratenseextract is convenient.

The unstructured grid finite volume method has been applied to predict the linear and nonlinear attenuation characteristics of the expansion chamber type silencer system. In order to achieve grid flexibility and a solution adaptation for geometrically complex flow regions associated with the actual silencers, the unstructured mesh algorithm in context with the node-centered finite volume method has been employed. The validation cases for the linear and nonlinear wave propagation characteristics include the acoustic field of the concentric expansion chamber and the axisymmetric blast flow field with the open end. Effects of the chamber geometry on the nonlinear wave propagation characteristics are discussed in detail.

We report on nonlinear optical image processing, such as image addition and subtraction, using photoinduced anisotropy in amorphous As_2S_3 thin film and propose a method for contrast reversal and edge enhancement of an image.

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