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Elucidate the role of the addition of calcium sulfate compound (CS) in experimentally manufactured dental calcium silicate cement (CSC) with the variation of hydration type of CS. Experimental CSC was synthesized by solid state reaction at 1,450℃. After treating the obtained clinker (mainly C3S with LSF 98.19) by ball milling, vibration milling, and finally jet milling, fine particles (mean 2.92 um, D90= 4.82 um) were obtained. After adding radiopacifying element (20 wt% ZrO2), different kinds of CS compounds (orthorhombic anhydrite, hemihydrate, dihydrate) were additionally added to the powder to control the setting and handling behaviors. For addition percentage of CS, 5 wt% adding condition was selected. Flow (ISO and LVDT method), Gilmore setting time, and penetration resistance were tested to evaluate the rheological properties during the setting reaction and compressive strength, were measured. For the wash-out resistance test, samples (400 rpm spinning) set for 150 s were exposed to water jet (60 mL/min, 18 G needle, 30 mm distance), and the eroded sample surfaces were 3D scanned, and the eroded sample volumes calculated with Catia V5 program. MTT cell viability and antibacterial activity were evaluated. The mean and S.D. values of physical properties are shown in Table 1. The type of CS significantly affected the setting time and degree of flowability (p0.05) compared to Control (without extract). The CV at 50% dilution satisfied the ISO requirement of above 70%. However, CV in extract with no dilution were lower than 70% for all the tested groups. Addition of CS in CSC increased antibacterial activity against E. coli. Inhibition zone could not be observed for all groups against E. faecalis. Selectively using different types of CS in CSC could be an efficient manufacturing tactic to satisfy the different property requirements in various clinical cases of sealing, pulpotomy, perforation, or retrograde filling, etc. [Display omitted] [ABSTRACT FROM AUTHOR]

Fixed dose complex dual-layer tablets of telmisartan and rosuvastatin calcium have been used for the treatment of hypertension and hyperlipidemia. However, the current United States Pharmacopoeia analysis method is limited by the need for twice the time and cost owing to analysis for each active pharmaceutical ingredient present separately. Due to the critical limitations in establishing simultaneous analysis methods for both active pharmaceutical ingredients, there is an urgent need for an analysis method that can be applied for immediate use by researchers. The objective of this study was to develop and validate a simultaneous quantitative assay using a rapid and selective high performance liquid chromatography method for the analysis of rosuvastatin calcium and telmisartan in fixed dose combination dual-layer tablet dosage forms. This method used Kinetex C18 (5 µm, 4.6×150 mm) columns at a flow rate of 1.0 ml/min and Ultraviolet-visible detector set at a wavelength of 242 nm. The separation was carried out using an ammonium phosphate monobasic buffer (pH 3.0) and methanol at a ratio of 300:700 as the mobile phase. The retention times of rosuvastatin calcium and telmisartan were 2.2 and 4.3 min respectively. The system suitability was 0.41 % for rosuvastatin calcium and 0.63 % for telmisartan, and the peak of each component showed complete separation from disturbance peaks. The correlation coefficient of the active pharmaceutical ingredients was approximately 0.999 when the concentration of rosuvastatin calcium was in the range of 4.44-26.6 µg/ml and the concentration of telmisartan was 0.176-106.6 µg/ml, this indicates good linearity. The recovery rate relative to the amount added was 97.0-99.6 % for rosuvastatin calcium and 95.5-102.2 % for telmisartan. Precision and solution stability were within the permissible range. Validation acceptance criteria were met in all cases. This simultaneous quantitative analysis method was successfully applied to the quality assessment of six fixed dose combination dual-layer tablets containing various amounts of rosuvastatin calcium and telmisartan. [ABSTRACT FROM AUTHOR]

In mammalian cells, the bulky DNA adducts caused by ultraviolet radiation are mainly repaired via the nucleotide excision repair (NER) pathway; some defects in this pathway lead to a genetic disorder known as xeroderma pigmentosum (XP). Ribosomal protein S3 (rpS3), a constituent of the 40S ribosomal subunit, is a multi-functional protein with various extra-ribosomal functions, including a role in the cellular stress response and DNA repair-related activities. We report that rpS3 associates with transcription factor IIH (TFIIH) via an interaction with the xeroderma pigmentosum complementation group D (XPD) protein and complements its function in the NER pathway. For optimal repair of UV-induced duplex DNA lesions, the strong helicase activity of the TFIIH complex is required for unwinding damaged DNA around the lesion. Here, we show that XP-D cells overexpressing rpS3 showed markedly increased resistance to UV radiation through XPD and rpS3 interaction. Additionally, the knockdown of rpS3 caused reduced NER efficiency in HeLa cells and the overexpression of rpS3 partially restored helicase activity of the TFIIH complex of XP-D cells in vitro. We also present data suggesting that rpS3 is involved in post-excision processing in NER, assisting TFIIH in expediting the repair process by increasing its turnover rate when DNA is damaged. We propose that rpS3 is an accessory protein of the NER pathway and its recruitment to the repair machinery augments repair efficiency upon UV damage by enhancing XPD helicase function and increasing its turnover rate. [ABSTRACT FROM AUTHOR]

Evaluate the effects of addition of ascorbic acid (AscA) to experimentally fabricated calcium silicate cement on setting time, flowability, and wash-out resistance properties. Experimental calcium silicate (CS) cement clinkers were synthesized via a solid state reaction at 1,450 ℃ for 15 min followed by quenching at 1,250 ℃, and the clinkers were pulverized by vibration milling and jet milling, The starting materials for calcium silicate clinker were CaCO 3 , SiO 2 , Al 2 O 3 , MgO, K 2 CO 3 , Na 2 CO 3 (LSF: 88.98, 98.19, and 108.43). After characterizing the obtained product using XRD/XRF/SEM/TEM/FT-IR, we chose the composition having a high percentage of tricalcium silicate phase and low free CaO content (LSH 98.19) as the main composition. Addition of ZrO 2 (20 wt%) to the jet-milled CS powder, and second addition of CaSO 4 ·½H 2 O (5 wt%) were done. AscA was incorporated into the mixing solution in various concentrations. The Gilmore setting time, flow test (ISO and LVDT method), penetration resistance, compressive strength, and wash-out resistance ('water jet' through 18 G needle for 5 s to 400 rpm-spinning 150 second-set CS cement sample with a flow rate of 60 mL/min, '3D scanning', and 'eroded volume calculation' with Catia V5 Program) were evaluated. MTT assay and antimicrobial tests were performed. AscA incorporation into experimentally fabricated CS cement reduces the setting time (p<0.01, r = -0.935), and affected the flowability, wash-out resistance, and compressive strength depending on the concentration (Table 1, Figure 1). AscA addition in experimental CS cement showed a statistically insignificant increase in cell viability (CV) at 25% extract concentration compared to the without addition group (p=0.064). However, at the higher extract concentration, there was no significant difference in CV between test groups. Antibacterial activity against E. Coli. and E. faecalis showed no meaningful difference between with-AscA (0.05 wt%) and without-AscA groups. The AscA incorporation in dental CS cement could be a promising method to improve the setting, physical, handling, and biological properties. [ABSTRACT FROM AUTHOR]

The Ge2Sb2Te5 thin films deposited by a sputtering method on SiO2/Si substrates were annealed through a rapid thermal annealing process and performed a high-resolution transmission electron microscopy study in order to investigate the atomic arrangement of the metastable Ge2Sb2Te5. The metastable rocksalt structure having face-centered-cubic lattice was confirmed by high-resolution transmission electron microscopy images and simulated images on the directions of <100>, <110>, and <211> zone axes. According to the position of Ge and Sb in the metastable rocksalt structure, the atomic distribution alters when observed in different direction and this causes change in the charge-density distribution, resulting in different images in a high-resolution transmission electron microscopy. It is expected that as the crystallization proceeds, the Ge and Sb atoms tend to position themselves on a specific plane. From this aspect, the ordered structure model of the metastable Ge2Sb2Te5 was proposed by varying the position of the Ge and Sb atoms. [ABSTRACT FROM AUTHOR]

Summary This work presents an iterative, water balance based approach to estimate actual evapotranspiration (ET) with integrated surface/subsurface flow models. Traditionally, groundwater level fluctuation methods have been widely accepted and used for estimating ET and net groundwater recharge; however, in watersheds where interactions between surface and subsurface flow regimes are highly dynamic, the traditional method may be overly simplistic. Here, an innovative methodology is derived and demonstrated for using the water balance equation in conjunction with a fully-integrated surface and subsurface hydrologic model (HydroGeoSphere) in order to estimate ET at watershed and sub-watershed scales. The method invokes a simple and robust iterative numerical solution. For the proof of concept demonstrations, the method is used to estimate ET for a simple synthetic watershed and then for a real, highly-characterized 7000 km 2 watershed in Southern Ontario, Canada (Grand River Watershed). The results for the Grand River Watershed show that with three to five iterations, the solution converges to a result where there is less than 1% relative error in stream flow calibration at 16 stream gauging stations. The spatially-averaged ET estimated using the iterative method shows a high level of agreement ( R 2 = 0.99) with that from a benchmark case simulated with an ET model embedded directly in HydroGeoSphere. The new approach presented here is applicable to any watershed that is suited for integrated surface water/groundwater flow modelling and where spatially-averaged ET estimates are useful for calibrating modelled stream discharge. [ABSTRACT FROM AUTHOR]

Hydrologic modeling requires the handling of a wide range of highly nonlinear processes from the scale of a hill slope to the continental scale, and thus the computational efficiency of the model becomes a critical issue for water resource management. This work is aimed at implementing and evaluating a flexible parallel computing framework for hydrologic simulations by applying OpenMP in the HydroGeoSphere (HGS) model. HGS is a 3D control-volume finite element model that solves the nonlinear coupled equations describing surface–subsurface water flow, solute migration and energy transport. The computing efficiency of HGS is improved by three parallel computing schemes: 1) parallelization of Jacobian matrix assembly, 2) multi-block node reordering for performing LU solve efficiently, and 3) parameter privatization for reducing memory access latency. Regarding to the accuracy and consistency of the simulation solutions obtained with parallel computing, differences in the solutions are entirely due to use of a finite linear solver iteration tolerance, which produces slightly different solutions which satisfy the convergence tolerance. The maximum difference in the head solution between the serial and parallel simulations is less than 10 −3 m, using typical convergence tolerances. Using the parallel schemes developed in this work, three key achievements can be summarized: (1) parallelization of a physically-based hydrologic simulator can be performed in a manner that allows the same code to be executed on various shared memory platforms with minimal maintenance; (2) a general, flexible and robust parallel iterative sparse-matrix solver can be implemented in a wide range of numerical models employing either structured or unstructured mesh; and (3) the methodology is flexible, especially for the efficient construction of the coefficient and Jacobian matrices, compared to other parallelized hydrologic models which use parallel library packages. [ABSTRACT FROM AUTHOR]

A formula for the optimal relation between the width of a planar conductor (w0), the total width of parallel straight planar conductors (W), and the number of the parallel conductors (N) for the minimum ohmic resistance is presented. The formula is verified for the frequency range between 2 and 27.12 MHz according to N by using the finite element method. By experimentation, it is also shown that the proposed formula can be applied to design low‐loss circular planar coils. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the association between serum osteoprotegerin (OPG) levels and subclinical atherosclerosis in premenopausal patients with systemic lupus erythematosus (SLE). Serum OPG levels and carotid artery intima-media thickness (IMT) were measured in 180 patients and 85 age-matched control subjects. It concludes that increased serum OPG level is associated with subclinical atherosclerosis in these patients.

Highlights: [•] A numerical model for NAPL-involved Compound Specific Isotope Analysis is presented. [•] The model was verified against various conditions necessary for Compound Specific Isotope Analysis. [•] The model is capable of simulating various types of NAPL-involved isotope models with complex conditions. [•] Isotope signatures can be significantly different when considering multiphase flow within the contaminant source zone. [ABSTRACT FROM AUTHOR]

Aim To assess the antibacterial efficacy of a human β-defensin-3 ( HBD3) peptide against Enterococcus faecalis biofilms. Methodology Standardized human dentine blocks were infected with E. faecalis ATCC 29212 for 3 weeks. Aqueous calcium hydroxide paste ( n = 12, CH), a 2% chlorhexidine gel ( n = 12, CHX), an HBD3 peptide gel ( n = 12) and saline ( n = 12) were tested as experimental groups. A mismatched peptide gel group ( n = 12, MP) and sterilized but noninoculated block group ( n = 12) were included as controls. After 1 week of medication, the dentinal samples at the depth of 200 and 400 μm were collected from medicated canal lumens. Bacterial growth was assessed by spectrophotometric analysis of optical density ( OD) after 72 h of incubation. Statistical analysis was performed with repeated-measures anova and Tukey's post hoc test. Results The HBD3 group was associated with significantly lower OD values ( P < 0.05) than the CH or CHX groups at both depths. The CH group did not differ significantly from MP or Saline group at either depth ( P > 0.05). There was no significant difference ( P > 0.05) in the OD values of the inner (200 μm) and outer (400 μm) dentinal samples for any group. Conclusions The HBD3 peptide inhibited the growth of E. faecalis biofilms in infected dentine blocks. [ABSTRACT FROM AUTHOR]

Among the various heavy metals, arsenic is frequently found in abandoned mine drainage and the environmental fate of arsenic in real aqueous solutions can be highly dependent on the presence of co-existing ions. In this study, removal of arsenate through adsorption on the reused aluminum oxide or through precipitation was investigated in a single and in a binary system as a function of pH and concentration. Different removal behaviors of arsenate were observed in the presence of different cations as well as a variation of the molar ratios of arsenate to cations. Co-operative effects on arsenate removal by precipitation in solution occurred with an increase of copper concentration, while a decrease of arsenate removal resulted in increasing calcium concentration. It was observed that the arsenate removal in the presence of calcium would be highly dependent on the molar ratios of both elements. [ABSTRACT FROM AUTHOR]

Summary: Groundwater age has become a fundamental concept in groundwater hydrology, but ages originating from isotopic analyses are still identified with a lack of clarity and using models that occasionally are unrealistic. If the effect of advection and dispersion on water ages has already been extensively identified, very few studies address the reliability of using radiometric ages as derived from isotopic data to estimate aquifer properties such as average velocities. Using simple one-dimensional and two-dimensional analytical solutions for single-site and two-sites mobile–immobile systems, we compare the radiometric ages to the mean ages (or residence times) as deduced from a direct, physically-based simulation approach (using the mean age equation), and show that the competition between isotope decay rate and dispersion coefficient can generate important discrepancies between the two types of ages. A correction for the average apparent velocity originating from apparent isotopic ages is additionally provided. The particular case of the tritium age dating method is also addressed, and a numerical example is finally given for illustrating the analysis considering a more complex and heterogeneous aquifer system. Our results suggest that age definitions based on the radioactivity of isotopes may not be representative for the mean age of the sample or for the groundwater velocity at given locations, and may not always be suitable for constraining the calibration of hydrogeological models. [ABSTRACT FROM AUTHOR]

This study was conducted to assess the genetic diversity, population structure and linkage disequilibrium (LD) of weedy rice in Korea using 73 weedy rice, 24 landrace lines, 12 breeding lines and 24 international varieties. In total, 772 alleles were detected in 63 microsatellite loci. The number of alleles per marker locus ranged from two to 40, with an average of 12.3. The gene diversity and polymorphism information content value averaged 0.694 and 0.668, with a range of 0.016-0.941 and 0.016-0.946 respectively. In a model-based analysis of population structure, Korean rice germplasm was classified into four subpopulations, designated 'cultivated indica', 'cultivated japonica', 'weedy indica', 'weedy japonica.' Pair-wise estimates of FST indicated different degrees of differentiation between the four model-based populations, with values ranging from 0.073 (between cultivated and weedy japonica) to 0.474 (between weedy japonica and weedy indica). The weedy indica population appeared to be highly differentiated, compared with the other populations. The cultivated indica lines had the highest gene diversity (0.58), followed by cultivated japonica (0.50), weedy japonica (0.42) and weedy indica (0.35). The total number of private alleles in weedy indica and japonica populations was 39 (23 markers) and 55 (22 markers) respectively. The average of LD (r2) of weedy indica and japonica types was higher than that of the two cultivated populations, both for inter- and intrachromosome values, indicating the possible reproductive and geographical isolation of sub-populations in cultivated rice fields. [ABSTRACT FROM AUTHOR]

An effective calculation method for AC resistance and the inductance of planar rectangular spiral coils is proposed. For the calculation, a volume filament model and its equivalent circuit are provided. By using the method, AC resistance and inductance are calculated accurately in megahertz frequency range by including both skin and proximity effects. The method is verified with experiments and used to optimise rectangular spiral coils for the maximum quality factor (Q‐factor) at 6.78 MHz. A small planar rectangular coil is shown to have the maximum Q‐factor when the width of the innermost coil loop is about a half of that of the outermost coil loop. [ABSTRACT FROM AUTHOR]

Abstract: The salinity of groundwater increases with depth in the Canadian Shield (up to 1.3kg/L of density). The existence of brine can be critically important for the safe geologic disposal of radioactive wastes, as dense brine can significantly retard the upward migration of radionuclides released from repositories. Static and flushing conditions of the deep brine are analyzed using a U-tube analogy model. Velocity reduction due to the presence of dense brine is derived under flushing conditions. A set of illustrative numerical simulations in a two-dimensional cross section is presented to demonstrate that dense brine can significantly influence regional groundwater flow patterns in a shield environment. It is implied from the results that (1) the existence of Shield brine can be an indicator of a hydrogeologically stable environment, (2) activities near ground surface may not perturb the stable groundwater environment in the deep brine region, and thus, (3) the deep brine region can be considered as a candidate geologic site for the safe disposal of waste. In addition to brine, other issues associated with long-term waste disposal, such as geological, glacial and seismic events, may need to be considered for the safe storage of spent nuclear fuel in a shield environment. [Copyright &y& Elsevier]

The PTO rattle noise of the direct engine-PTO driveline was caused by the collisions between the driving and driven gears in the PTO gearbox due to their velocity variations induced by the torque fluctuations transmitted from the engine (Part II, companion article). This indicated that the speed variation must be reduced to reduce the PTO rattle noise. In this study, a torsional damper was used to reduce the speed variations in the PTO driveline. A torsional damper comprised of two helical coil springs was installed on the engine flywheel to reduce the torque fluctuations causing the speed variations and gear collisions in the PTO gearbox during idling. The effects of design parameters of the torsional damper on the speed variation were investigated, and their optimum values were found by using an 11-degree of freedom, non-linear model of the damped PTO driveline. Under a constant hysteresis torque, the speed variation increased with the torsional stiffness of the damper. When the optimum values of the first spring were used, the sound pressure level of the rattle noise was reduced, resulting in a reduction of 15 dBA. The optimum torsional damper also reduced the velocity variation of the driving gear in the PTO gearbox, resulting in a noise reduction of 15 dBA. The torsional damper performed well in reducing the rattle noise caused by velocity variation in the direct engine-PTO driveline. [ABSTRACT FROM AUTHOR]

To investigate the causes of the PTO rattle noise of a direct engine-PTO driveline, a 10-degree of freedom non-linear mathematical model of the driveline was developed and verified experimentally. The model was used to simulate dynamic characteristics of the driveline motions and the effects of driveline parameters on the PTO rattle noise under the condition that generated the loudest PTO rattle noise. The results of the simulation identified that the PTO rattle noise was caused by collisions between the driving and driven gears in the PTO gearbox due to their velocity variations induced by the torque fluctuations from the engine. It was also found that the PTO rattle noise decreased as the drag torque and the mass moment of inertia of the engine flywheel increased. Smaller backlash and mass moment of inertia of the driven gear also reduced the PTO rattle noise. However, increasing the drag torque and mass moment of inertia of the engine flywheel or decreasing the backlash and mass moment of inertia of the driven gear are not practical due to their detrimental effects on the transmission efficiency, gear strength, and smooth operations of gears. These methods are not suggested as being appropriate for solving the PTO rattle noise problem of the tractor used in this study. Instead, we recommend considering use of a torsional damper as a means of reducing velocity variations of the PTO driveline, which was a primary cause of the PTO rattle noise. [ABSTRACT FROM AUTHOR]

Introduction of a direct engine-PTO driveline has reduced production costs and increased power transmission efficiency. However, a severe rattle noise was generated in the PTO gearbox during idling. This study was conducted to: (1) investigate characteristics of the PTO rattle noise and to determine how much it should be reduced (Part I, this article); (2) use computer simulation to investigate the primary causes of PTO rattle noise and the effects of some driveline design parameters on PTO rattle noise (Part II, companion article); and (3) investigate reduction of PTO rattle noise by a torsional damper (Part III, companion article). The PTO rattle noise of the tractor used in this study was measured at 30 mm from the PTO shaft and analyzed in both time and frequency domains to investigate its temporal and spectral characteristics. The loudest PTO rattle noise was 102 dBA at the PTO shaft and occurred at an engine idle speed of 880 rpm with the PTO gear in neutral. The sound pressure of the noise varied periodically with the same period of the engine expansion strokes. Its frequency bandwidth was as wide as from 0.5 to 10.0 kHz, and the peak sound pressure occurred at frequencies of 3.6, 6.5, and 7.8 kHz, which corresponded to the natural frequencies of the driven gear in the PTO gearbox. The engine speed did not affect the spectral characteristics of the PTO rattle noise. The PTO rattle noise of the tractor used in this study was at least 7 dBA higher on average than those of the imported tractors having the same type of PTO driveline. This meant that the PTO rattle noise of the direct engine-PTO driveline in this study must be reducted by at least 7 dBA. [ABSTRACT FROM AUTHOR]

This study examined the potential reuse of powdered wastes (PW) generated during the sanding and sawing process in a local chemical company in Korea with the viewpoint of the recycling these wastes and minimizing the level of contamination. As the aluminium hydroxide inside the PW could be thermally converted to various types of aluminium oxides depending on the calcination temperature, the adsorptive properties could be changed and it may affect on adsorption ability. Calcination of the PW was performed for 3 h at 550°C, 750°C, and 950°C. From the results, amorphous aluminium oxide was thermally generated by calcinating the PW at 5508C and with further increase of temperature to 950°C, the crystallinity of amorphous aluminium oxide was gradually increased. The physicochemical analysis of calcined powdered wastes (CPW) at various temperatures showed that more developed porosity was noted in the CPW as the calcinations temperature increased, whereas surface area was significantly decreased from 175.5m² g-1 to 46.5m² g-1. The removal efficiency of arsenate on the CPW decreased as the calcinations temperature increased from 550°C to 950°C. The CPW550 exhibited the highest adsorption capacities toward arsenate over pH range of 2-8 and showed a complete removal of the arsenate (10.0mgL-1) within the first 10 min. Adsorption kinetic studies showed that the rate of arsenic adsorption on the CPW decreased with the increase of the calcination temperature. When the maximum adsorption capacity of arsenic onto the CPW was calculated by Langmuir equation, the CPW550 has the highest value as 43.9mgg-1. [ABSTRACT FROM AUTHOR]

Abstract: In general, the accuracy of numerical simulations is determined by spatial and temporal discretization levels. In fractured porous media, the time step size is a key factor in controlling the solution accuracy for a given spatial discretization. If the time step size is restricted by the relatively rapid responses in the fracture domain to maintain an acceptable level of accuracy in the entire simulation domain, the matrix tends to be temporally over-discretized. Implicit sub-time stepping applies smaller sub-time steps only to the sub-domain where the accuracy requirements are less tolerant and is most suitable for problems where the response is high in only a small portion of the domain, such as within and near the fractures in fractured porous media. It is demonstrated with illustrative examples that implicit sub-time stepping can significantly improve the simulation efficiency with minimal loss in accuracy when simulating flow and transport in fractured porous media. The methodology is successfully applied to density-dependent flow and transport simulations in a Canadian Shield environment, where the flow and transport is dominated by discrete, highly conductive fracture zones. [Copyright &y& Elsevier]

With the recognition of certain limitations of ex situ methods for conservation of plant genetic resources the Convention on Biological Diversity (CBD) at the ‘Earth Summit’ in 1992 highlighted the importance of traditional knowledge of indigenous and local communities that are relevant for the conservation and sustainable use of biological diversity and gave considerable attention to on-farm and other forms of in situ conservation. Unlike semi-static nature of ex situ conservation the in situ or on-farm conservation (OFC) is a dynamic evolutionary process. In developing countries like Republic of Korea, where there is a continuum between the use of traditional and modern cultivars, integration of OFC with already existing gene-bank activities in the country will be an effective approach for conservation and sustainable use of the country's crop genetic resources. However, very little efforts have been made so far in developing strategies for OFC, therefore, in this paper we describe the importance of OFC and strategies for its development in Republic of Korea. Surveys over the last 20 years have shown that the landraces of major crops have been almost replaced by newly bred varieties in the country. But some vegetatively propagated or minor crop species are still being maintained in the farmers’ fields. We have identified crop landraces, which can be classified into four different categories from the OFC point of view. These are vegetatively propagated landraces, sexually reproduced landraces, landraces with improved varieties and landraces cultivated for the reasons of personal preference. The related issues on OFC including implementation methods from the point of national cooperative system in designated specific condition are also discussed to ensure the genetic diversity in the fast changing agro-ecosystem of the country. [ABSTRACT FROM AUTHOR]

A neutron induced prompt γ -ray spectrometry (NIPS) facility has been developed at the Nuclear Chemistry Research Division, of the Korea Atomic Energy Research Institute (KAERI) with the aim of analyzing the major components of various elements in aqueous samples. The facility is equipped with a 252Cf neutron source and a γ-γ coincidence setup with two n-type coaxial HPGe detectors based on NIM spectrometric modules in association with data acquisition and spectral analysis systems. The development of the system, its set-up and the calibration of detection efficiency up to 8 MeV using a set of radionuclides and the (n,γ) reactions of chlorine are described in the paper. [ABSTRACT FROM AUTHOR]

We investigated five single-nucleotide polymorphism (SNP) sites of tumor necrosis factor-α (TNF-α) promoter, the distribution of five-locus TNF-α haplotypes, and extended human leukocyte antigen (HLA)/TNF-α haplotypes in 200 parents from 100 unrelated Korean families. TNF-α SNPs were typed using polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) and PCR restriction fragment length polymorphism (PCR-RFLP) methods. The frequencies of −1031C, −863A, −857T, −308A, and −238A alleles were 0.185, 0.145, 0.140, 0.060, and 0.040, respectively. The allele frequencies in Koreans were similar to those of Japanese. A total of five TNF-α haplotypes (−1031/−863/−857/−308/−238) were detected in 196 parents: TCCGG (frequency 0.617), CACGG (0.143), TCTGG (0.143), TCCAG (0.061), and CCCGA (0.036). Five most common extended HLA/TNF-α haplotypes (frequencies >0.020) accounted for 16% (63/392) of the total haplotypes. A total of 223 HLA haplotypes and 239 HLA/TNF-α haplotypes were detected, indicating that most HLA haplotypes are exclusively associated with particular TNF-α haplotypes. [ABSTRACT FROM AUTHOR]

The bonded area is largely affected by the surface morphology and mechanical properties of materials by surface activated bonding (SAB) process, because the room temperature bonding process is carried out under a low temperature and low pressure for short time. Accordingly, interfacial defects cause fatally harmful problems in many cases. For an application of this technique, it is important to know the effect of interfacial defects on fracture behavior. The fracture mechanism and its criterion for the growth of interfacial defects were investigated using the Al/sapphire joint. It became clear that the growth of interfacial defects is the dominant factor for crack propagation. An estimation of stress intensity factor for the growth of interfacial defects was tried in two ways, stress criterion and energy criterion. A critical stress intensity factor for the growth of interfacial defects was estimated as 0.3–0.5 MPa m[sup 1/2] by the analysis of FEM calculation and experimental observation. [ABSTRACT FROM AUTHOR]

Summary objective This study was designed to investigate whether an elevated serum antithyroglobulin antibody (TgAb) reflects cancer recurrence in thyroglobulin (Tg)-undetectable patients with differentiated thyroid carcinoma (DTC) after thyroid ablation. design We measured serum TgAb level and evaluated the disease status in 226 DTC patients who had undergone remnant ablation and showed an undetectable Tg result as assessed by immunoradiometric assay. measurements Radioligand assay of TgAb was performed. Recurrence was assessed by 131 I scan, 18 F-fluorodeoxyglucose positron emission tomography, sonography, computed tomography, or by surgical operation. results Fifty-one patients (22·6%) of the Tg-undetectable patients showed positive TgAb, and 25 (49·0%) of these were confirmed with recurrence. The recurrence rate of TgAb-positive patients was higher than that of TgAb-negative patients (3·4%; P < 0·0001). During follow-up, 73·1% of the disease-free patients showed spontaneously decreased TgAb levels. A total of 71·4% of patients with recurrent cancer, who showed responses to surgical operation or radio-iodine treatment, also showed a decreased TgAb level. conclusions Persistently elevated TgAb levels appear to serve as a useful marker for recurrent or persistent DTC in patients with undetectable serum Tg results. Thus, the routine measurement of TgAb in such patient populations may be indicated. [ABSTRACT FROM AUTHOR]

Weathered granitic residual soils, which are found in much of the Korean peninsula, pose unique challenges in terms of internal stability and filtration. The particle transport and filtration behavior of two extreme soil types, named Shinnae-dong and Poi-dong, are investigated in this paper. The erodibilities of the two soils are evaluated using constant flow-rate experiments on both undisturbed samples and samples with cylindrical holes. A comparison of the results from these experiments revealed the extent of particle redeposition and self-filtration in the internal erosion process. In spite of the differences in the mineralogical properties and engineering characteristics of the two soils, the size of the eroded particles from the two soils fell within the same range of 1–100 µm. The two soils were coupled with filters, chosen according to the US Bureau of Reclamation's (USBR) filter criteria, to determine the efficiency of filters in minimizing erosion. It was found that the filters significantly minimized the erosion of the two base soils. However, the associated reductions in filter permeability are greater than one order of magnitude. Experiments using filters alone with particulate suspensions as the influents enabled the evaluation of a coefficient, λ, which could be used to characterize the particle retention capacities of the filters.Key words: particle transport, residual soils, filtration, drainage, Korean peninsula, soil filter criteria.Les sols résiduels granitiques qui se retrouvent dans une grande partie de la péninsule coréenne présentent des défis uniques quant à la stabilité interne et la filtration. Dans cet article, on étudie le transport et la filtration de particules de deux types extrêmes de sols appelés Shinnae-dong et Poi-dong. Les susceptibilités à l'érosion des deux sols sont évaluées au moyen d'expériences à débit constant tant sur des échantillons intacts que sur des échantillons avec des trous cylindriques. Une comparaison des résultats de ces expériences ont révélé l'étendue de la redéposition et de l'autofiltration au cours du processus d'érosion interne. En dépit des différences dans les propriétés minéralogiques et dans les caractéristiques mécaniques des deux sols, les dimensions des particules érodées des deux sols se situaient dans la même plage de 1 à 100 µm. Les deux sols ont été couplés avec des filtres choisis d'après les critères de filtre du USBR pour déterminer l'efficacité des filtres pour minimiser l'érosion. On a trouvé que les filtres minimisaient de façon significative l'érosion des deux sols de base. Cependant, les réductions résultantes de la perméabilité des filtres sont plus grandes qu'un ordre de grandeur. Des expériences sur des filtres seuls avec des suspensions de particules comme influx ont permis d'évaluer le coefficient λ qui peut être utilisé pour caractériser les capacités de rétention des particules des filtres.Mots clés : transport de particules, sols résiduels, filtration, drainage, péninsule coréenne, critères de filtre du sol.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Background: The constituents of nasal mucus may be contaminated by plasma if there is epistaxis. Gross epistaxis is apparent as a red lavage fluid, while microepistaxis may yield a clear fluid. If gross or microepistaxis are present, it will be difficult to decide whether plasma protein concentrations are elevated because of plasma exudation or bleeding. In order to discriminate between these two possibilities, we measured erythrocyte-derived free hemoglobin (fHb) in nasal lavage fluids. Methods: Single-blinded subjects underwent standard hypertonic saline nasal provocation. Unilateral hypertonic nasal provocation was performed in normal, allergic rhinitis (AR) and nonallergic rhinitis (NAR) subjects (total of 1316 specimens). fHb was measured using the Sigma-Aldrich kit (St. Louis, MO). Grossly bloody specimens were analyzed separately from the remainder. Statistical analysis defined the means and 95th percentiles for fHb and albumin in the nonbloody normal group. Results: fHb concentrations ranged from below the limits of detection (< 1 µg/ml) to > 164 µg/ml fHb was 79.3 µg/ml ± 4.7 (mean ± SEM) in four normal, 31 AR and 25 NAR grossly bloody specimens. The 95th percentile of fHb in the nonbloody normal samples (n = 68 subjects, n = 681 specimens) was 16.5 µg/ml. This value was defined as the threshold to detect potential microepistaxis, and corresponded to approximately 245 000 erythrocytes per ml of lavage fluid. Total protein (P < 0.05) and albumin (P < 0.001), but not markers of glandular secretion, were significantly increased in samples with fHb > 16.5 µg/ml compared to those ≤ 16.5 µg/ml. Elevations of fHb without changes in albumin were more prevalent in nonallergic rhinitis. Conclusions: Significant bleeding into nasal lavage samples can contaminate the specimens and increase the concentrations of both fHb and plasma proteins. Increased albumin alone would indicate increased vascular... [ABSTRACT FROM AUTHOR]

Dewatering is a common engineering practice to secure the accessibility during the construction and operational phases of tunnels. It is thus important to accurately estimate the amount of groundwater flow into underground openings for the design and safe operation of tunnels. Numerical models need to be used to estimate groundwater flow into openings for given heterogeneity and regional hydrologic boundary conditions typically by assuming that the atmospheric pressure is maintained along open wall faces. As the scale of openings can be small as tens of centimeters, while models need to incorporate the regional hydrologic conditions, it is often practically impossible to explicitly represent the three-dimensional (3D) geometry of openings within numerical models. For the safety assessment of deep geological repositories of spent nuclear fuels, for example, complex configurations and geometry of various tunnels such as construction, access, ventilation, and deposition tunnels often need to be approximated as one-dimensional (1D) lines in 3D models. The application of a simple Dirichlet boundary condition along a set of tunnel nodes may yield inaccurate solutions due to geometric simplifications and coarse discretization. This study derives an appropriate boundary condition that can be applied to 1D tunnel segments to improve the accuracy when simulating inflow into openings. A third-type tunnel boundary condition is suggested to correct the difference between known wall pressure and the pressure simulated at tunnel nodes. Improvement in the precision of the solutions is demonstrated by comparing the numerical solutions using the new boundary condition with analytic solutions, and with numerical solutions when the 3D tunnel geometry is explicitly simulated. It is also shown that the formulation can be easily extended to incorporate the high permeability excavation damaged zone and the low permeability grouted zone in the tunnel vicinity. The applicability of the tunnel boundary condition is demonstrated using an example of a hypothetical deep geologic repository system consisting of various types of tunnels located in a hypothetical crystalline coastal aquifer. • For the design and safe operation of underground facilities, accurate estimation of groundwater inflow is essential. • A Cauchy-type boundary condition is derived that can be applicable to the tunnel segments in numerical models. • The new boundary condition can account for the excavation damaged zone (EDZ) and the grouted zone in the tunnel vicinity. • The applicability of the boundary condition is demonstrated using an example of a hypothetical geologic repository system. [ABSTRACT FROM AUTHOR]

Another version of dynamic time warping (DTW), called branch-and-bound DTW (BnB-DTW), is proposed, which adaptively controls its global path constraints by reflecting the contents of input patterns. Experimental results show that the suggested DTW algorithm performs more efficiently than conventional DTW approaches. [ABSTRACT FROM AUTHOR]

An adaptive acoustic echo cancellation method based on independent component analysis, which can remove nonlinear echo components, is presented. Since this method takes into account the independence between a far-end signal and the echo-cancelled output to cancel acoustic echoes which are independent of near-end signals, it can continue to update AEC parameters even in double-talk situations, thereby improving the cancellation performance. Experiments show that the proposed method provides better performance than the conventional least-mean-square methods for both linear and nonlinear AEC systems without requiring separate double-talk detection (DTD). [ABSTRACT FROM AUTHOR]

The article presents a study on an analysis of laterally loaded drilled shafts in rock profiles by Robert Liang, Ke Yang and Jamal Nusairat. It enumerates the various issues that the discussers have advanced in consideration of the authors. Meanwhile, it presents several graphs that depict the ultimate resistance for wedge and rock mass failure method.

This study evaluated the accuracy of cefotetan susceptibility determination using the MicroScan WalkAway system for AmpC-producing Klebsiella pneumoniae. In total, 57 K. pneumoniae isolates that showed a D-shape flattening in a double-disk synergy test were studied. Cefotetan MICs were determined by the agar dilution method. The blaDHA gene was detected in all 57 isolates, one of which co-harboured blaCMY-1. According to the MicroScan system, 28 isolates were susceptible, 18 were intermediately-resistant, and 11 were resistant to cefotetan. Compared with the agar dilution method, very major, minor and major error rates were 28.1% (16/57), 47.4% (27/57) and 1.8% (1/57), respectively. [ABSTRACT FROM AUTHOR]

Summary: In aged population, the association of thyroid hormones on physical performance, especially within their normal range, has yet to be elucidated. In this study, individuals with low serum free T3/free T4 were likely to have low muscle mass and impaired physical performance. Purpose: We aimed to evaluate the associations of muscle mass, strength, and physical performance with thyroid hormone in an aged euthyroid population from a community-based cohort. Methods: We examined 918 men aged over 60 years and 1215 postmenopausal women from the Ansung cohort study. Appendicular skeletal muscle mass divided by square of height (ASM/ht2) was used as the muscle mass index. Hand grip strength was measured using a hydraulic dynamometer. Physical performance was assessed using the short physical performance battery (SPPB). Results: Participants with higher tertiles of free T3 and free T3/free T4 were younger and had higher ASM/ht2, stronger hand grip strength, and higher SPPB scores than those in the lower tertiles. In adjusted models, men within higher tertiles of free T3 had higher ASM/ht2 compared with those within lower tertiles (p = 0.033), whereas subjects with higher tertiles of free T4 had lower ASM/ht2 compared with those within lower tertiles (p = 0.043). Subjects within higher tertiles of free T3/free T4 had higher ASM/ht2 (p < 0.001) and better physical performance (p = 0.048) than those within lower tertiles after adjustments. However, free T3, free T4, or free T3/free T4 was not related to hand grip strength after adjustment for covariates. Conclusion: Our results thus indicate that in an aged euthyroid population, low serum free T3/free T4 was a better index for low muscle mass and impaired physical performance than serum free T3 or free T4 alone. [ABSTRACT FROM AUTHOR]

This Letter focuses on extracting the heartbeat information using ultra‐wideband impulse radar, and a new method that can extract not only the heart rate but also the timing of the heartbeat with high accuracy is proposed herein. As the first step towards achieving this goal, radar pulses are projected towards a human body, and the reflected pulses are accumulated along the time axis at specific time intervals. The accumulated pulses pass through a digital filter to reveal the heartbeat information and are converted to a greyscale image. A pattern that reflects the heartbeats is used as a template to find similar patterns in the entire image. After all the significant patterns are found, the timing information corresponding to the locations where the patterns appear is calculated, and this indicates the time when the heartbeats actually occur. From the experimental results, the authors confirmed that the proposed method could estimate the heart rate with high accuracy and extract the timing information of the heartbeats. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the exchange coupling between adjacent ferromagnetic cobalt zirconium layers separated by nonmagnetic silver layer for cobalt zirconium/ silver/cobalt zirconium trilayer films through ferromagnetic resonance (FMR). Observation of the derivative resonance signals in the magnetic field range; Analysis of the FMR spectra of single layer.

The effects of InGaAs/GaNAs barrier combinations were investigated in the metal organic vapor phase epitaxy grown GaInNAs quantum wells (QWs). Significant improvement was made in the optical performance of the 1.3 μm range with the proposed structures. Structural investigation linked with the optical properties reveals that a thin InGaAs layer, placed between GaInNAs QWs and GaNAs layers, plays a role in redistributing the nitrogen within the QWs while maintaining a sharp interface. The amount of diffused nitrogen is proportional to the strain residing in the InGaAs layer, which explains the tendency of blueshift with the increase in GaNAs thickness. [ABSTRACT FROM AUTHOR]

We report a method to fabricate carbon nanotubes (CNT)/conducting polymer composite films for the application of CNTs to field emission displays. The composite was prepared by a combination of electrochemical polymerization of pyrrole and electrophoretic deposition of CNTs. We obtained a uniform CNT/conducting polypyrrole polymer composite film. The CNTs were mainly coated on protrusions of the polypyrrole film and emitted electrons without rubbing and stretching. We realized a triode-type field emission array (FEA) using the CNT/polypyrrol composite. This FEA showed that the emission current was modulated by gate voltage of 30 V. The film morphology and emission characteristics of the CNT/conducting polymer composite were studied using optical microscopy, scanning electron microscopy, and an emission test in vacuum. [ABSTRACT FROM AUTHOR]

We report on the effects of the wet and dry oxidation processes on the interfacial roughness and time dependent dielectric breakdown (TDDB) characteristics of the poly-Si/SiO[sub 2]/Si(100) trilayer. The interface roughness of the oxide layers buried under a thick poly-Si electrode has been investigated using an x-ray reflectivity technique. Analysis of x-ray reflectivity data for the trilayer samples and for a bare oxide film shows that interface roughness of poly-Si electrode/SiO[sub 2] interfaces depends on oxidation process while oxide layers have smooth SiO[sub 2]/Si-subtstrate interfaces. TDDB of the SiO[sub 2] layer has also been observed to depend on the oxidation process, indicating that the interface roughness is a crucial factor affecting the TDDB characteristics. The wet oxidized SiO[sub 2] film is more stable to dielectric breakdown and has smoother interfaces than the dry oxidized sample. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A formula for the optimal relation between the width of a planar conductor (w0), the total width of parallel straight planar conductors (W), and the number of the parallel conductors (N) for the minimum ohmic resistance is presented. The formula is verified for the frequency range between 2 and 27.12 MHz according to N by using the finite element method. By experimentation, it is also shown that the proposed formula can be applied to design low-loss circular planar coils. [ABSTRACT FROM AUTHOR]

Summary: This study aimed to evaluate the effect of acupuncture and intervention types on weight loss. We searched electronic databases, including Embase, PubMed, CENTRAL, RISS, KISS and CNKI, for randomized controlled trials that used acupuncture to treat obesity before June 2017. We found 27 trials involving 32 intervention arms and 2,219 patients. Acupuncture plus lifestyle modification (LM) was more effective than LM alone (Hedges' g = 1.104, 95% CI = 0.531–1.678) and sham acupuncture plus LM (Hedges' g = 0.324, 95% CI = 0.177–0.471), whereas acupuncture alone was not more effective than sham acupuncture alone and no treatment. Auricular acupuncture (Hedges' g = 0.522, 95% CI = 0.152–0.893), manual acupuncture (Hedges' g = 0445, 95% CI = 0.044–0.846) and pharmacopuncture (Hedges' g = 0.411, 95% CI = 0.026–0.796) favoured weight loss. Finally, acupuncture treatment was effective only in subjects with overweight (25 ≤ body mass index < 30, Hedges' g = 0.528, 95% CI = 0.279–0.776), not in subjects with obesity (body mass index ≥30). Our study suggests that the effect of acupuncture on weight loss may be maximized when auricular and manual acupuncture or pharmacopuncture treatment is combined with LM in patients with overweight. [ABSTRACT FROM AUTHOR]

Presents a study which derived an equivalent noise source with a useful functional form for Boltzmann transport equations from the classical expression of the noise source. Methods used in understanding the noise phenomena in semiconductor devices; Mathematical expression for n-type nondegenerate semiconductor; Discussion on the controversy over correctness of an equation of the spectral intensity of the noise source.

Focuses on a study which reinvestigated the steady-state Nyquist theorem for multi-terminal semiconductor devices and its application to minimum noise figure in microwave field effect transistors. Discussion on the existing thermal noise theories for multi-terminal semiconductor devices; Methodology of the study; Results and discussion.

Deals with a steady-state Nyquist theorem for multi-terminal nondegenerate semiconductor devices. Derivation of formulas for the spectral intensities of the short-circuit thermal noise currents in arbitrarily shaped multi-terminal semiconductor devices under direct current bias; Experimental details; Result of the study.

An effective calculation method for AC resistance and the inductance of planar rectangular spiral coils is proposed. For the calculation, a volume filament model and its equivalent circuit are provided. By using the method, AC resistance and inductance are calculated accurately in megahertz frequency range by including both skin and proximity effects. The method is verified with experiments and used to optimise rectangular spiral coils for the maximum quality factor (Q-factor) at 6.78 MHz. A small planar rectangular coil is shown to have the maximum Q-factor when the width of the innermost coil loop is about a half of that of the outermost coil loop. [ABSTRACT FROM AUTHOR]