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Metal chalcogenides are widely studied as thermoelectric materials due to their finely tunable electronic transport properties over a wide temperature range. FeSe2 has recently been considered a promising thermoelectric material with investigations focusing on restraining bipolar behavior through doping. In this study, a series of Cl-doped FeSe2 compositions, a series of FeSe2 − xClx (x = 0, 0.01, 0.025, and 0.05) compositions, were synthesized to investigate the influence of Cl doping. While the gradually decreasing lattice parameters with doping content x suggests successful doping up to x = 0.05, the hole concentration slightly decreased owing to electrons generated by the Cl doping. Nevertheless, the electrical conductivity and Seebeck coefficient show no systematic change with x owing to very low electron generating efficiency, and no distinctive enhancement of power factor is seen for the doped samples. On the other hand, the lattice thermal conductivity gradually and significantly decreased with x from 9.2 W/mK to 6.3 W/mK for x = 0.05 by 32% at 300 K, which is originated from the effective additional phonon scattering due to the difference in mass (55%) and size (9%) between Se2− and Cl− ions. Consequently, a thermoelectric figure of merit is increased to 0.073 from 0.057 at 600 K for x = 0.05. [ABSTRACT FROM AUTHOR]

With the growing popularity of consumer-grade electroencephalogram (EEG) devices for health, entertainment, and cognitive research, assessing their signal quality is essential. In this study, we evaluated four consumer-grade wireless and dry-electrode EEG systems widely used for brain-computer interface (BCI) research and applications, comparing them with a research-grade system. We designed an EEG phantom method that reproduced µV-level amplitude EEG signals and evaluated the five devices based on their spectral responses, temporal patterns of event-related potential (ERP), and spectral patterns of resting-state EEG. We discovered that the consumer-grade devices had limited bandwidth compared with the research-grade device. A late component (e.g., P300) was detectable in the consumer-grade devices, but the overall ERP temporal pattern was distorted. Only one device showed an ERP temporal pattern comparable to that of the research-grade device. On the other hand, we confirmed that the activation of the alpha rhythm was observable in all devices. The results provide valuable insights for researchers and developers when it comes to selecting suitable EEG devices for BCI research and applications. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) has a detrimental impact on brain function, affecting various aspects such as cognition, memory, language, and motor skills. Previous research has dominantly used electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) to individually measure brain signals or combine the two methods to target specific brain functions. However, comprehending Alzheimer's disease requires monitoring various brain functions rather than focusing on a single function. This paper presents a comprehensive research setup for a monitoring platform for AD. The platform incorporates a 32-channel dry electrode EEG, a custom-built four-channel fNIRS, and gait monitoring using a depth camera and pressure sensor. Various tasks are employed to target multiple brain functions. The paper introduced the detailed instrumentation of the fNIRS system, which measures the prefrontal cortex, outlines the experimental design targeting various brain functioning programmed in BCI2000 for visualizing EEG signals synchronized with experimental stimulation, and describes the gait monitoring hardware and software and protocol design. The ultimate goal of this platform is to develop an easy-to-perform brain and gait monitoring method for elderly individuals and patients with Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a biomass-based, eco-friendly, and biodegradable aliphatic polyester. Compared to aromatic polyesters, PLA is not suitable for applications that require high strength and heat resistance. In this study, the extrusion parameters of the melt-spinning process of PLA, namely, the godet temperature (95 and 100 °C), draw ratio (2.0–4.0), and take-up speed (4000–4400 m/min) were optimized. As the draw ratio and take-up speed of the fiber increased, the tensile strength and melting temperature increased owing to orientation-induced crystallization until necking of the fibers occurred. The properties of the PLA fibers were measured using X-ray diffraction, a universal testing machine, differential scanning calorimetry, and Fourier-transform infrared spectroscopy. The maximum crystallinity achieved in the PLA fiber was 84.76%. The tensile strength of the fiber was increased from 86.25 to 124.06 MPa and the melting temperature was increased from 149.51 to 155.14 °C. Therefore, it is concluded that understanding the correlation between the process parameters and fibers and combining them appropriately facilitates the control of the mechanical and thermal properties of the PLA fiber. [ABSTRACT FROM AUTHOR]

We consider the motion of an incompressible shear-thickening power-law-like non-Newtonian fluid in R 3 with a variable power-law index. This system of nonlinear partial differential equations arises in mathematical models of electrorheological fluids. The aim of this paper is to investigate the large-time behaviour of the difference u - u ~ where u is a strong solution of the given equations with the initial data u 0 and u ~ is the strong solution of the same equations with perturbed initial data u 0 + w 0 . The initial perturbation w 0 is not required to be small, but is assumed to satisfy certain decay condition. In particular, we can show that (1 + t) - γ 2 ≲ ‖ u ~ (t) - u (t) ‖ 2 ≲ (1 + t) - γ 2 , for sufficiently large t > 0 , where γ ∈ (2 , 5 2) . The proof is based on the observation that the solution of the linear heat equation describes the asymptotic behaviour of the solutions of the electrorheological fluids well for sufficiently large time t > 0 , and the generalized Fourier splitting method with an iterative argument. Furthermore, it will also be discussed that the argument used in the present paper can improve the previous results for the generalized Newtonian fluids with a constant power-law index. [ABSTRACT FROM AUTHOR]

Tricalcium oxy silicate (C3S) and dicalcium silicate (C2S) are the major constituents of cement. In this study, the reactivity of polymorphs of calcium silicates is quantitatively investigated using Density Functional Theory. The result of combining the DFT calculation and the Bader charge analysis elucidates that the main difference in reactivity between C3S and C2S is the presence of oxy ions in C3S which has smaller partial charge compared to that of other oxygen in the crystals. For the C3S, the reactivity of among different C3S polymorphs is decisively affected by the Bader charge of oxy ions. In contrast, total internal energy of C2S determines the quantitative chemical reactivity of C2S polymorphs. This result suggests that oxy ion has more dominant impact on the thermodynamic stability of calcium silicates. Furthermore, total energy can be used to estimate the chemical reactivity of calcium silicates, where there is no oxy ion exists. [ABSTRACT FROM AUTHOR]

The minimization of error generation in machine tool spindle is important because high-speed and ultra-precision machining are extensively utilized in industrial fields. The thermal deformation of the machine tool spindle generated by the frictional heat between the outer and inner bearings can deteriorate the machining accuracy. In this study, a TiC−SUS431 composite was fabricated using the liquid pressing infiltration method to suppress thermal deformation, and its thermal properties were obtained by thermal characteristic tests. For the transient thermal analysis with finite element analysis, the parameters of the machine tool spindle-bearing model were selected, and the boundary conditions were calculated. The temperature and thermal deformation of the analysis model were compared by applying SCM415 and TiC−SUS431 to the material of the machine tool spindle and changing the rotation speed. From the analysis results, it was demonstrated that the TiC−SUS431 machine tool spindle can improve the machining accuracy by minimizing the spindle thermal deformation. [ABSTRACT FROM AUTHOR]

This study examines how the complex flow structure within a gas turbine rotor affects aerodynamic loss. An unshrouded linear turbine cascade was built, and velocity and pressure fields were measured using a 5-hole probe. In order to elucidate the effect of tip clearance, the overall aerodynamic loss was evaluated by varying the tip clearance and examining the total pressure field for each case. The tip clearance was varied from 0% to 4.2% of blade span and the chord length based Reynolds number was fixed at 2×105. For the case without tip clearance, a wake downstream of the blade trailing edge is observed, along with hub and tip passage vortices. These flow structures result in profile loss at the center of the blade span, and passage vortex related losses towards the hub and tip. As the tip clearance increases, a tip leakage vortex is formed, and it becomes stronger and eventually alters the tip passage vortex. Because of the interference of the secondary tip leakage flow with the main flow, the streamwise velocity decreases while the total pressure loss increases significantly by tenfold in the last 30% blade span region towards the tip for the 4.2% tip clearance case. It was additionally observed that the overall aerodynamic loss increases linearly with tip clearance. [ABSTRACT FROM AUTHOR]

Melanoma is a disease with a high recurrence rate and poor prognosis; therefore, the need for targeted therapeutics is steadily increasing. Oligodendrocyte transcription factor2 (Olig2) is a basic helix-loop-helix transcription factor that is expressed in the central nervous system during embryonic development. Olig2 is overexpressed in various malignant cell lines such as lung carcinoma, glioma and melanoma. Olig2 is known as a key transcription factor that promotes tumor growth in malignant glioma. However, the role of Olig2 in melanoma is not well characterized. We analyzed the role of Olig2 in apoptosis, migration, and invasion of melanoma cells. We confirmed that Olig2 was overexpressed in melanoma cells and tissues. Reduction of Olig2 increased apoptosis in melanoma cells by increasing p53 level and caspase-3/-7 enzyme activity. In addition, downregulation of Olig2 suppressed migration and invasion of melanoma cells by inhibiting EMT. Reduction of Olig2 inhibited expression of MMP-1 and the enzyme activity of MMP-2/-9 induced by TGF-β. Moreover, Olig2 was involved in the downstream stages of MEK/ERK and PI3K/AKT, which are major signaling pathways in metastatic progression of melanoma. In conclusion, this study demonstrated the crucial roles of Olig2 in apoptosis, migration, and invasion of melanoma and may help to further our understanding of the relationship between Olig2 and melanoma progression. [ABSTRACT FROM AUTHOR]

High interstitial Fe–Cr–Mn–C–N stainless steels, CN66 (0.38 wt% N + 0.28 wt% C) and CN71 (0.44 wt% N + 0.27 wt% C), were cast under atmospheric pressure to develop a new drill collar for use in petroleum industry. To evaluate the corrosion property, CN66 and CN71 were compared with high-Mn stainless steel, P550, which is currently being used as a drill collar material. Through the measurement of the corrosion resistance based on the chemical compositions, CN71 exhibited the highest corrosion property, a mean of 35.74, corresponding to strong corrosion resistance. However, CN71 exhibited a mean of 0.517 mpy for the corrosion rate compared to 0.37 mpy for P550, after the immersion experiment in 3.5 wt% NaCl. With high C content, the formation of carbide along the grain boundaries in CN71 and CN66 caused intergranular corrosion. However, this could be restricted by heat treatment at 1050 °C and 1180 °C with uniform distributions of chemical compositions via air cooling, decreasing the corrosion rates significantly. [ABSTRACT FROM AUTHOR]

This paper presents the conditions and PD controller to swing-up the Acrobot to which a spring is attached at the passive joint (first joint). Because the motion of the system is in the vertical plane, there are some system parameters associated with gravity. The range of a spring constant and controller gain that allow the PD controller to swing-up the system is defined depending on these parameter values. To prove that the PD controller makes the system approach the equilibrium points, one of which is swing-up state (upright equilibrium point, UEP), the motion of the first link is analyzed according to the motion of the second link and the torque on the active joint (second joint) with an actuator. Among these equilibrium points, the conditions that can only converge to the UEP of the system are found. [ABSTRACT FROM AUTHOR]

Physical neural networks made of analog resistive switching processors are promising platforms for analog computing. State-of-the-art resistive switches rely on either conductive filament formation or phase change. These processes suffer from poor reproducibility or high energy consumption, respectively. Herein, we demonstrate the behavior of an alternative synapse design that relies on a deterministic charge-controlled mechanism, modulated electrochemically in solid-state. The device operates by shuffling the smallest cation, the proton, in a three-terminal configuration. It has a channel of active material, WO3. A solid proton reservoir layer, PdHx, also serves as the gate terminal. A proton conducting solid electrolyte separates the channel and the reservoir. By protonation/deprotonation, we modulate the electronic conductivity of the channel over seven orders of magnitude, obtaining a continuum of resistance states. Proton intercalation increases the electronic conductivity of WO3 by increasing both the carrier density and mobility. This switching mechanism offers low energy dissipation, good reversibility, and high symmetry in programming. Designing energy efficient neural networks based on synaptic memristor devices remains a challenge. Here, the authors propose the development of a 3-terminal WO3 synaptic device based on proton intercalation in inorganic materials by leveraging a solid proton reservoir layer PdHx as the gate terminal. [ABSTRACT FROM AUTHOR]

This paper describes a new algorithm that generates a cartoon-style bas-relief surface from photographs of general scenes. Most previous methods for bas-relief generation have focused on accurate restoration of input 3D models on a background plane. The generation of bas-reliefs with artistic effects has rarely been studied. Considering that non-photorealistic rendering (NPR) techniques are currently very popular and 3D printing technology is developing rapidly, extending NPR techniques to the generation of a bas-relief surface with artistic effects is natural and valuable. Furthermore, cartoon is a basic non-realistic and artistic style familiar to general users. From this motivation, our method focuses on generating a cartoon-style bas-relief surface. We use the lens blur function of Google Camera, which is a smartphone application, to obtain a photograph and its depth map as inputs. Using coherent line drawing and histogram-based quantization methods, we construct a depth map that contains the salient features of given input scenes in abstract form. Displacement mapping from the depth map onto a thin plane generates a cartoon-style bas-relief. Experimental results show that our method generates bas-relief surfaces that contain the characteristics of cartoons, such as coherent border lines and quantized layers. [ABSTRACT FROM AUTHOR]

Chemical leukoderma is an acquired type of vitiligo that can be initiated by various exogenous chemicals such as hydroquinone (HQ), rhododendrol (RD), or 4-tertiary butyl phenol (4-TBP). Despite the importance of epidermal keratinocytes in diverse dermatological conditions, their toxicological role in chemical leukoderma is poorly understood. To elucidate their role in the pathogenesis of chemical leukoderma, genome-scale transcriptional analysis was performed in human epidermal keratinocytes (HEKs) treated with a sub-cytotoxic HQ concentration (10 µM). The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway-based functional enrichment analysis of HQ-induced differentially expressed genes (DEGs) revealed that HQ significantly upregulated DEGs related to the IL-17 signaling pathway and significantly downregulated DEGs associated with melanogenesis in HEKs. The meta-analysis between the HQ-induced and cytokine-induced transcriptional data (GSE53751) showed that 58 DEGs were commonly upregulated between HQ- and IL-17A-treated HEKs. Notably, the expression of IL36G was significantly increased in HEKs in response to both HQ and IL-17A. IL-36γ (2 µg/ml) directly inhibits melanin biosynthesis in cultured human epidermal melanocytes (HEMs) and downregulates the gene transcription of key enzymes in the melanogenesis pathway including TYR, DCT, and TYRP1. Moreover, IL-36γ autocrinally regulated keratinocyte function to produce the proinflammatory cytokines IL-36γ, IL-6, and CXCL8/IL-8 in a concentration-dependent manner, suggesting that IL-36γ may stimulate the amplification cycle of cutaneous inflammation. In this regard, hydroquinone-induced IL-36γ from human keratinocytes plays a pivotal role in the development of chemical leukoderma by autocrinally or paracrinally modulating the crosstalk between keratinocytes and melanocytes. [ABSTRACT FROM AUTHOR]

Avobenzone is the most commonly used ultraviolet (UV) A filter ingredient in sunscreen. To investigate the biological activity of avobenzone in normal human epidermal keratinocytes (NHEKs), the genome-scale transcriptional profile of NHEKs was performed. In this microarray study, we found 273 up-regulated and 274 down-regulated differentially expressed genes (DEGs) in NHEKs treated with avobenzone (10 μM). Gene Ontology (GO) enrichment analysis showed that avobenzone significantly increased the DEGs associated with lipid metabolism in NHEKs. In addition, avobenzone increased the gene transcription of peroxisome proliferator-activated receptor γ (PPARγ) and fatty acid binding protein 4 in NHEKs, implicating that avobenzone may be one of the metabolic disrupting obesogens. To confirm the obesogenic potential, we examined the effect of avobenzone on adipogenesis in human bone marrow mesenchymal stem cells (hBM-MSCs). Avobenzone (EC50, 14.1 μM) significantly promoted adipogenesis in hBM-MSCs as its positive control obesogenic chemicals. Avobenzone (10 μM) significantly up-regulated mRNA levels of PPARγ during adipogenesis in hBM-MSCs. However, avobenzone did not directly bind to PPARγ and the avobenzone-induced adipogenesis-promoting activity was not affected by PPARγ antagonists T0070907 and GW9662. Therefore, avobenzone promoted adipogenesis in hBM-MSCs through a PPARγ-independent mechanism. This study suggests that avobenzone functions as a metabolic disrupting obesogen. [ABSTRACT FROM AUTHOR]

This paper is an attempt to reconcile two different perspectives and come up with a more comprehensive conceptualization of university autonomy by adopting a stakeholder approach in identifying indicators of university autonomy. One perspective views university autonomy as a protection of academic freedom and the other as a performance enhancer. In order to secure public support for university autonomy, a strategy to satisfy both perspectives is required. A stakeholder approach helps identifying stakeholder interests which leads to an analysis of what is expected in return for university autonomy. University autonomy indicators developed out of these interests would facilitate a measure to evaluate and secure academic freedom and institutional autonomy in a way that secures better support for university autonomy from higher education stakeholders. This paper examines existing literature to identify higher education stakeholders and their interests and comes up with an example of autonomy indicators that reflect these interests. [ABSTRACT FROM AUTHOR]

Chrysanthemum stunt viroid (CSVd), the smallest plant pathogen known to infect chrysanthemums, is a single-stranded circular RNA viroid that induces stunting that results in an overall height reduction of 30-50 % in mature plants. A catalytic single-chain variable antibody, 3D8 scFv, which exhibits intrinsic DNase and RNase activities, was expressed in chrysanthemums to generate transgenic plant resistance to CSVd infection. Moreover, a codon-optimized version of the 3D8 scFv gene for chrysanthemums was also transformed into plants; these codon-optimized transgenic chrysanthemums expressed twice as much 3D8 scFv and displayed 60 % more resistance to CSVd infection, compared with transgenic chrysanthemums harboring the original 3D8 scFv gene. CSVd challenge experiments with codon-optimized and original 3D8 scFv-transgenic chrysanthemums showed that CSVd in newly produced leaves of both codon-optimized and original 3D8 scFv-transgenic plants was not detected by RT-PCR. This is the first report describing the development of a CSVd-resistant chrysanthemum harboring a catalytic single-chain antibody, 3D8 scFv, which has intrinsic RNase activity. [ABSTRACT FROM AUTHOR]

Tomato chlorosis virus (ToCV) is a whitefly-transmitted crinivirus that causes interveinal chlorosis and bronzing on tomato leaves. Although outbreaks of ToCV have been reported in many countries, the virus was not reported in Korea until 2013. To identify weed hosts of ToCV that may serve as virus reservoirs, we analyzed various weeds that were growing together with ToCV-infected tomatoes and viruliferous Bemisia tabaci in a tomato greenhouse. We performed reverse transcription-polymerase chain reaction (RT-PCR) analysis of root samples from 148 samples of 61 species from 24 families of plants grown in the greenhouse to avoid possible ToCV contamination by whiteflies on leaves. Seventeen weed species were identified as ToCV hosts based on RT-PCR results of root samples: Conyza canadensis, Erigeron annuus, Sonchus asper, Youngia japonica, Trigonotis peduncularis, Cardamine flexuosa, Cerastium glomeratum, Stellaria media, Chenopodium album, Ipomoea hederacea, Quamoclit coccinea, Vicia angustifolia var. segetilis, V. tetrasperma, Phytolacca americana, Mazus pumilus, Solanum americanum and S. nigrum. The amplicons obtained by RT-PCR were confirmed as ToCV by sequence analysis. Life cycle analysis of the weeds indicated that each weed could play an important role as a 'green bridge' or virus reservoir between tomato cultivation seasons. This is the first report documenting the possible occurrence of ToCV in tomato plants based on weed life cycles. [ABSTRACT FROM AUTHOR]

The protein 3D8 single-chain variable fragment (3D8 scFv) has potential anti-viral activity due to its ability to penetrate into cells and hydrolyze nucleic acids. Probiotic Lactobacillus paracasei engineered to secrete 3D8 scFv for oral administration was used to test the anti-viral effects of 3D8 scFv against gastrointestinal virus infections. We found that injection of 3D8 scFv into the intestinal lumen resulted in the penetration of 3D8 scFv into the intestinal villi and lamina propria. 3D8 scFv secreted from engineered L. paracasei retained its cell-penetrating and nucleic acid-hydrolyzing activities, which were previously shown with 3D8 scFv expressed in Escherichia coli. Pretreatment of RAW264.7 cells with 3D8 scFv purified from L. paracasei prevented apoptosis induction by murine norovirus infection and decreased messenger RNA (mRNA) expression of the viral capsid protein VP1. In a mouse model, oral administration of the engineered L. paracasei prior to murine norovirus infection reduced the expression level of mRNA encoding viral polymerase. Taken together, these results suggest that L. paracasei secreting 3D8 scFv provides a basis for the development of ingestible anti-viral probiotics active against gastrointestinal viral infection. [ABSTRACT FROM AUTHOR]

Of the many materials and methodologies aimed at producing low-cost, efficient photovoltaic cells, inorganic-organic lead halide perovskite materials appear particularly promising for next-generation solar devices owing to their high power conversion efficiency. The highest efficiencies reported for perovskite solar cells so far have been obtained mainly with methylammonium lead halide materials. Here we combine the promising-owing to its comparatively narrow bandgap-but relatively unstable formamidinium lead iodide (FAPbI3) with methylammonium lead bromide (MAPbBr3) as the light-harvesting unit in a bilayer solar-cell architecture. We investigated phase stability, morphology of the perovskite layer, hysteresis in current-voltage characteristics, and overall performance as a function of chemical composition. Our results show that incorporation of MAPbBr3 into FAPbI3 stabilizes the perovskite phase of FAPbI3 and improves the power conversion efficiency of the solar cell to more than 18 per cent under a standard illumination of 100 milliwatts per square centimetre. These findings further emphasize the versatility and performance potential of inorganic-organic lead halide perovskite materials for photovoltaic applications. [ABSTRACT FROM AUTHOR]

Background: Rapidly evolving advances in the understanding of theorized unique driver mutations within individual patient's cancers, as well as dramatic reduction in the cost of genomic profiling, have stimulated major interest in the role of such testing in routine clinical practice. The aim of this study was to report our initial experience with genomic testing in heavily pretreated breast cancer patients. Methods: Patients with primary or recurrent breast cancer managed at any of our five hospitals and whose malignancy had failed to respond to therapy or had progressed on all recognized standard-of-care options were offered the opportunity to have their cancer undergo next-generation sequencing genomic profiling. Results: Of a total of 101 patients, 98 (97 %) had at least one specific genomic alteration identified. A total of 465 different somatic genetic abnormalities were revealed in this group of patients. Although 52 % of patients were found to have an abnormality for which an U.S. Food and Drug Administration (FDA)-approved drug was available, 69 % of patients had an FDA-approved agent for an indication other than breast cancer. The most common genomic alterations of potential clinical consequence were PIK3 (25 %), FGFR1 (16 %), AKT (11 %), PTEN (10 %), ERBB2 (8 %), JAK2 (6 %), and RAF1 (5 %). Conclusions: Almost all advanced breast cancers possess at least one well-characterized genomic alteration that might be actionable at the clinical level. Further, in most cases, a plausible argument can be advanced for the potential biological and clinical relevance of an FDA-approved antineoplastic agent not currently indicated in the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Organolead trihalide perovskite materials have been successfully used as light absorbers in efficient photovoltaic cells. Two different cell structures, based on mesoscopic metal oxides and planar heterojunctions have already demonstrated very impressive advances in performance. Here, we report a bilayer architecture comprising the key features of mesoscopic and planar structures obtained by a fully solution-based process. We used CH3NH3 Pb(I1 − xBrx)3 (x = 0.1-0.15) as the absorbing layer and poly(triarylamine) as a hole-transporting material. The use of a mixed solvent of γ-butyrolactone and dimethylsulphoxide (DMSO) followed by toluene drop-casting leads to extremely uniform and dense perovskite layers via a CH3NH3I-PbI2-DMSO intermediate phase, and enables the fabrication of remarkably improved solar cells with a certified power-conversion efficiency of 16.2% and no hysteresis. These results provide important progress towards the understanding of the role of solution-processing in the realization of low-cost and highly efficient perovskite solar cells. [ABSTRACT FROM AUTHOR]

Tomato yellow leaf curl virus (TYLCV), a member of the genus Begomovirus, has a single-stranded DNA genome. TYLCV can induce severe disease symptoms on tomato plants, but other hosts plants such as cucurbits and peppers are asymptomatic. A full-length DNA clone of a Korean TYLCV isolate was constructed by rolling-circle amplification from TYLCV-infected tomatoes in Korea. To assess relative susceptibility of sweet pepper varieties to TYLCV, 19 cultivars were inoculated with cloned TYLCV by agro-inoculation. All TYLCV-infected sweet peppers were asymptomatic, even though Southern hybridization and polymerase chain reaction analysis showed TYLCV genomic DNA accumulation in roots, stems, and newly produced shoots. Southern hybridization indicated that TYLCV replicated and moved systemically from agro-inoculated apical shoot tips to roots or newly produced shoots of sweet peppers. Whitefly-mediated inoculation experiments showed that TYLCV can be transmitted to tomatoes from TYLCV-infected sweet peppers. Taken together, these results indicate that sweet pepper can be a reservoir for TYLCV in nature. [ABSTRACT FROM AUTHOR]

The possibility of a new technique for fabricating nanoparticles from thin films using selective oxidation in an atmosphere mixture of water vapor and hydrogen was investigated. Fe-5wt.%Al films were RF-sputtered and annealed in the atmosphere mixture at 900°C for up to 200 min, in order to oxidize aluminum selectively. Thermodynamics simulation showed that temperatures exceeding 800°C are necessary to prevent iron from being oxidized, as confirmed by the depth profile of XPS. As the annealing time increased, the morphology of the 200-nm Fe-Al films changed from the continuous to the discontinuous type; thus, particulate Fe-Al films formed after 100 min. The particulate 10- to 100-nm Fe-Al films showed super-paramagnetic behavior after the oxidation. Thus, a new technique for fabricating nanoparticles was successfully introduced using selective oxidation. [ABSTRACT FROM AUTHOR]

Major challenges of clustering geo-referenced data include identifying arbitrarily shaped clusters, properly utilizing spatial information, coping with diverse extrinsic characteristics of clusters and supporting region discovery tasks. The goal of region discovery is to identify interesting regions in geo-referenced datasets based on a domain expert's notion of interestingness. Almost all agglomerative clustering algorithms only focus on the first challenge. The goal of the proposed work is to develop agglomerative clustering frameworks that deal with all four challenges. In particular, we propose a generic agglomerative clustering framework for geo-referenced datasets (GAC-GEO) generalizing agglomerative clustering by allowing for three plug-in components. GAC-GEO agglomerates neighboring clusters maximizing a plug-in fitness function that capture the notion of interestingness of clusters. It enhances typical agglomerative clustering algorithms in two ways: fitness functions support task-specific clustering, whereas generic neighboring relationships increase the number of merging candidates. We also demonstrate that existing agglomerative clustering algorithms can be considered as specific cases of GAC-GEO. We evaluate the proposed framework on an artificial dataset and two real-world applications involving region discovery. The experimental results show that GAC-GEO is capable of identifying arbitrarily shaped hotspots for different data mining tasks. [ABSTRACT FROM AUTHOR]

The modeling of genetic regulatory networks is becoming increasingly widespread in the study of biological systems. In the abstract, one would prefer quantitatively comprehensive models, such as a differential-equation model, to coarse models; however, in practice, detailed models require more accurate measurements for inference and more computational power to analyze than coarse-scale models. It is crucial to address the issue of model complexity in the framework of a basic scientific paradigm: the model should be of minimal complexity to provide the necessary predictive power. Addressing this issue requires a metric by which to compare networks. This paper proposes the use of a classical measure of difference between amplitude distributions for periodic signals to compare two networks according to the differences of their trajectories in the steady state. The metric is applicable to networks with both continuous and discrete values for both time and state, and it possesses the critical property that it allows the comparison of networks of different natures. We demonstrate application of the metric by comparing a continuous-valued reference network against simplified versions obtained via quantization. [ABSTRACT FROM AUTHOR]

The performance of a designed digital filter is measured by the sum of the errors of the optimal filter and the estimation error. Viewing an image at a high resolution results in optimal filters having smaller errors than at lower resolutions; however, higher resolutions bring increased estimation error. Hence, choosing an appropriate resolution for filter design is important. The present paper provides expressions for both the error of the optimal filter and the design error for estimating optimal filters in a pyramidal multiresolution framework. The analysis is facilitated by a general characterization of suitable sequences of resolution-constraint mappings. The error expressions are generated from resolution to resolution in a telescoping manner. To take advantage of data at all resolutions, one can use a hybrid multiresolution design to arrive at a multiresolution filter. A sequence of filters is designed using data at increasing resolutions, each filter serves as a prior filter for the next, and the last filter is taken as the designed filter. The value of the multiresolution filter at a given observation is based on the highest resolution at which conditioning by the observation is considered significant. [ABSTRACT FROM AUTHOR]

Orthohantaviruses, negative-sense single-strand tripartite RNA viruses, are a global public health threat. In humans, orthohantavirus infection causes hemorrhagic fever with renal syndrome or hantavirus cardiopulmonary syndrome. Whole-genome sequencing of the virus helps in identification and characterization of emerging or re-emerging viruses. Next-generation sequencing (NGS) is a potent method to sequence the viral genome, using molecular enrichment methods, from clinical specimens containing low virus titers. Hence, a comparative study on the target enrichment NGS methods is required for whole-genome sequencing of orthohantavirus in clinical samples. In this study, we used the sequence-independent, single-primer amplification, target capture, and amplicon NGS for whole-genome sequencing of Hantaan orthohantavirus (HTNV) from rodent specimens. We analyzed the coverage of the HTNV genome based on the viral RNA copy number, which is quantified by real-time quantitative PCR. Target capture and amplicon NGS demonstrated a high coverage rate of HTNV in Apodemus agrarius lung tissues containing up to 103–104 copies/μL of HTNV RNA. Furthermore, the amplicon NGS showed a 10-fold (102 copies/μL) higher sensitivity than the target capture NGS. This report provides useful insights into target enrichment NGS for whole-genome sequencing of orthohantaviruses without cultivating the viruses. [ABSTRACT FROM AUTHOR]

Interest in circulating RNAs for monitoring and diagnosing human health has grown significantly. There are few datasets describing baseline expression levels for total cell-free circulating RNA from healthy control subjects. In this study, total extracellular RNA (exRNA) was isolated and sequenced from 183 plasma samples, 204 urine samples and 46 saliva samples from 55 male college athletes ages 18-25 years. Many participants provided more than one sample, allowing us to investigate variability in an individual's exRNA expression levels over time. Here we provide a systematic analysis of small exRNAs present in each biofluid, as well as an analysis of exogenous RNAs. The small RNA profile of each biofluid is distinct. We find that a large number of RNA fragments in plasma (63%) and urine (54%) have sequences that are assigned to YRNA and tRNA fragments respectively. Surprisingly, while many miRNAs can be detected, there are few miRNAs that are consistently detected in all samples from a single biofluid, and profiles of miRNA are different for each biofluid. Not unexpectedly, saliva samples have high levels of exogenous sequence that can be traced to bacteria. These data significantly contribute to the current number of sequenced exRNA samples from normal healthy individuals. [ABSTRACT FROM AUTHOR]

Presents an abstract for the article on the nonlinear stochastic determination of gene expression using cDNA microarrays.