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Introduction: Clarithromycin resistance is a crucial factor in the eradication of Helicobacter pylori. This study aimed to evaluate the performance of MmaxSure™ H. pylori & ClaR Assay (MmaxSure™) in the diagnosis and detection of clarithromycin resistance in H. pylori. Methods: Subjects who underwent esophagogastroduodenoscopy between April 2020 and October 2022 were enrolled. The diagnostic performances of MmaxSure™ and dual priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) were compared with the rapid urease test and culture. Secondary gene sequencing analysis was performed in discordant cases of PCR tests. Results: A total of 156 gastric biopsy samples were analyzed. In H. pylori detection, MmaxSure™ showed a 95.9% sensitivity (95% CI: 90.6–98.6), a 42.7% specificity (95% CI: 26.3–60.7), and a kappa value of 0.457. For the detection of A2143G mutation samples, MmaxSure™ showed a 91.2% sensitivity (95% CI: 76.3–98.1), a 93.4% specificity (95% CI: 87.5–97.1), and a kappa value of 0.804. There were a total of 10 discordant cases compared to gene sequencing in A2143G mutation detection for MmaxSure™. Conclusion: In this study, MmaxSure™ showed comparable diagnostic performance to DPO-PCR in the detection of the H. pylori and A2143G mutation. Further research is needed to confirm the clinical effectiveness of the MmaxSure™ assay in H. pylori eradication. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to compare susceptibility map-weighted imaging (SMwI) using various MRI machines (three vendors) with N-3-fluoropropyl-2-β-carbomethoxy-3-β-(4-iodophe nyl)nortropane (18F-FP-CIT) PET in the diagnosis of neurodegenerative parkinsonism in a multi-centre setting. Methods: We prospectively recruited 257 subjects, including 157 patients with neurodegenerative parkinsonism, 54 patients with non-neurodegenerative parkinsonism, and 46 healthy subjects from 10 hospitals between November 2019 and October 2020. All participants underwent both SMwI and 18F-FP-CIT PET. SMwI was interpreted by two independent reviewers for the presence or absence of abnormalities in nigrosome 1, and discrepancies were resolved by consensus. 18F-FP-CIT PET was used as the reference standard. Inter-observer agreement was tested using Cohen's kappa coefficient. McNemar's test was used to test the agreement between the interpretations of SMwI and 18F-FP-CIT PET per participant and substantia nigra (SN). Results: The inter-observer agreement was 0.924 and 0.942 per SN and participant, respectively. The diagnostic sensitivity of SMwI was 97.9% and 99.4% per SN and participant, respectively; its specificity was 95.9% and 95.2%, respectively, and its accuracy was 97.1% and 97.7%, respectively. There was no significant difference between the results of SMwI and 18F-FP-CIT PET (p > 0.05, for both SN and participant). Conclusions: This study demonstrated that the high diagnostic performance of SMwI was maintained in a multi-centre setting with various MRI scanners, suggesting the generalisability of SMwI for determining nigrostriatal degeneration in patients with parkinsonism. Key Points: • Susceptibility map-weighted imaging helps clinicians to predict nigrostriatal degeneration. • The protocol for susceptibility map-weighted imaging can be standardised across MRI vendors. • Susceptibility map-weighted imaging showed diagnostic performance comparable to that of dopamine transporter PET in a multi-centre setting with various MRI scanners. [ABSTRACT FROM AUTHOR]

Near-eye display technology is a rapidly growing field owing to the recent emergence of augmented and mixed reality. Ultrafast response time, high resolution, high luminance, and a dynamic range for outdoor use are all important for non-pixelated, pupil-forming optics. The current mainstream technologies using liquid crystals and organic materials cannot satisfy all these conditions. Thus, finely patterned light-emissive solid-state devices with integrated circuits are often proposed to meet these requirements. In this study, we integrated several advanced technologies to design a prototype microscale light-emitting diode (LED) arrays using quantum dot (QD)-based color conversion. Wafer-scale epilayer transfer and the bond-before-pattern technique were used to directly integrate 5-µm-scale GaN LED arrays on a foreign silicon substrate. Notably, the lithography-level alignment with the bottom wafer opens up the possibility for ultrafast operation with circuit integration. Spectrally pure color conversion and solvent-free QD patterning were also achieved using an elastomeric topographical mask. Self-assembled monolayers were applied to selectively alter the surface wettability for a completely dry process. The final emissive-type LED array integrating QD, GaN, and silicon technology resulted in a 1270 PPI resolution that is far beyond the retinal limit. Augmented reality technologies typically rely on near-eye displays, which requires displays with very high resolutions. Here, Bae et al demonstrate a quantum-dot integrated GaN light emitting diode arrays with a pixels per inch resolution of 1270, well beyond the retinal limit. [ABSTRACT FROM AUTHOR]

Display technology with ultrafine pixels for near-eye application is a rapidly growing field due to the recent emergence of augmented/mixed reality. With the constant demand for high energy efficiency, long lifetime, and high luminosity, micro-LED displays based on compound semiconductors are promising candidates for such applications. However, miniaturizing LEDs results in significant drawbacks in terms of their quantum efficiency, current injection efficiency, and heat extraction. With relatively low device resistance compared to that of liquid crystals or organic LEDs, micro-LEDs are also more susceptible to the effects of parasitic resistance. In this study, gallium nitride based micro-LED displays with very small pixels (5 μm pixel, 10 μm pitch) are fabricated to study the thermal–electrical effect of meshed hybrid conductors on the optical emission efficiency. In situ thermographic imaging with I–V measurement confirms a significant trade-off among heat transfer, electrical conductivity, and light extraction efficiency. An increase of 37.9% in the emission efficiency (2540 pixels per inch, 5 μm pixels, 1 mm2 display, at 49.2 °C) is achieved by optimizing the thermal and electrical conduction paths. This study experimentally confirms the importance of thermal management and multi-physics analysis in designing ultra-small-pixel micro-LEDs with high energy efficiency. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to examine the instrumental use of social capital regarding career growth within an organization, focusing on the mediating role of perceived competence mobilization and the moderating role of two situational variables: perceived external prestige and job insecurity climate. Design/methodology/approach: Relationships among the constructs are predicted based on relevant literature, and are tested using survey results from 324 employees working in 14 leading corporations in Korea. Findings: Results show that social capital positively influenced, via perceived competence mobilization, each of two career growth dimensions (i.e. the personal efforts to develop a career and the experience of being rewarded by the organization). In contrast, moderated path analysis indicated that perceptions of external prestige and job insecurity climate failed to moderate the indirect effect of social capital on career growth. Practical implications: In light of the instrumental use of social capital and the ensuring mechanism of competence mobilization, a detailed understanding of this effect on career growth cannot only neutralize the fears of brain drain, but is also helpful in providing possibilities for building new career development strategies. Originality/value: Although social capital has become an influential concept in social sciences, little evidence has been presented on the above relationship, particularly from the perspective of careerist orientation. This may be the first research examining how and when the influence of social capital becomes instrumental with respect to career attainment within an organization. [ABSTRACT FROM AUTHOR]

Semiconductors doped with magnetic ion, the so-called diluted magnetic semiconductors, are promising candidates for spintronics. Herein, we report on magnetic anisotropy in Mn:Ge diluted magnetic semiconductor nanowires. We grew single crystal Mn:Ge nanowires vertically on a Ge substrate and found the anisotropy in ratios of orbital to spin magnetic moments in the angle-dependent x-ray magnetic circular dichroism measurements. Our further characterization indicates that this anisotropy comes from the unique characteristics of nanowires, i.e., very high aspect ratio in their shape and tensile stress along the longitudinal direction, which confine the spins along the longitudinal direction and make an easy axis in that direction. [ABSTRACT FROM AUTHOR]

However, the correct affiliation should be "Division of Gastroenterology, Department of Internal Medicine, Incheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea". The published affiliation reads as "Division of Gastroenterology, Department of Internal Medicine, Incheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Incheon, Republic of Korea". [Extracted from the article]

Obtaining a quantitative description of the membrane proteins stability is crucial for understanding many biological processes. However the advance in this direction has remained a major challenge for both experimental studies and molecular modeling. One of the possible directions is the use of coarse-grained models but such models must be carefully calibrated and validated. Here we use a recent progress in benchmark studies on the energetics of amino acid residue and peptide membrane insertion and membrane protein stability in refining our previously developed coarse-grained model (Vicatos et al., Proteins 2014;82:1168). Our refined model parameters were fitted and/or tested to reproduce water/membrane partitioning energetics of amino acid side chains and a couple of model peptides. This new model provides a reasonable agreement with experiment for absolute folding free energies of several ??-barrel membrane proteins as well as effects of point mutations on a relative stability for one of those proteins, OmpLA. The consideration and ranking of different rotameric states for a mutated residue was found to be essential to achieve satisfactory agreement with the reference data. [ABSTRACT FROM AUTHOR]

The two-dimensional (2D) growth of cubic-structured (silicon) Si nanosheets (SiNSs) was investigated. Freestanding, single-crystalline SiNSs with a thickness of 5-20 nm were grown on various Si substrates under an atmospheric chemical vapor deposition process. Systematic investigation indicated that a diffusion-limited aggregation (DLA) environment that leads to dendritic growth in <110> directions at the initial stage is essential for 2D growth. The kinetic aspects under DLA environments that ascribe to the dendritic and 2D growth were discussed. Under the more dilute conditions made by addition of Ar to the flow of H, the SiNSs grew epitaxially on the substrates with periodic arrangement at a specific angle depending on the orientation of the substrate. It reveals that SiNSs always grew two dimensionally with exposing (111) surfaces. That is thermodynamically favorable. [ABSTRACT FROM AUTHOR]

The single living cell action potential was measured in an intracellular mode by using a vertical nanoelectrode. For intracellular interfacing, Si nanowires were vertically grown in a controlled manner, and optimum conditions, such as diameter, length, and nanowire density, were determined by culturing cells on the nanowires. Vertical nanowire probes were then fabricated with a complimentary metal-oxide-semiconductor (CMOS) process including sequential deposition of the passivation and electrode layers on the nanowires, and a subsequent partial etching process. The fabricated nanowire probes had an approximately 60-nm diameter and were intracellular. These probes interfaced with a GH cell and measured the spontaneous action potential. It successfully measured the action potential, which rapidly reached a steady state with average peak amplitude of approximately 10 mV, duration of approximately 140 ms, and period of 0.9 Hz. [ABSTRACT FROM AUTHOR]

The recent demonstration of thermal conductivity of rough electrolessly etched Si nanowire (Hochbaum et al., Nature, 451:163, ) attracted a lot of interest, because it could not be explained by the existing theory; thermal conductivity of rough Si nanowires falls below the boundary scattering of the thermal conductivity. However, nanoscale pores presented in the nanowires (Hochbaum et al., Nano Letters, 9:3550-3554, ) hinder one to be fully convinced that the surface roughness solely made a contribution to the significant reduction in thermal conductivity. In this study, we synthesized vapor-liquid-solid (VLS) grown rough SiGe nanowire and measured and theoretically simulated thermal conductivity of the nanowire. The thermal conductivity of rough SiGe nanowire is an order of magnitude lower than that of bulk SiGe and around a factor of four times lower than that of smooth SiGe nanowire. This significant reduction could be explained by the fact that the surface roughness scatters medium-wavelength phonons, whereas the long-wavelength phonons are scattered by phonon boundary scattering, and the short-wavelength phonons are scattered by alloy scattering. [ABSTRACT FROM AUTHOR]

In this paper, we synthesize VLS-grown rough Si nanowires using Mn as a catalyst with various surface roughnesses and diameters and measured their thermal conductivities. We grew the nanowires by a combination vapor-liquid-solid and vapor-solid mechanism for longitudinal and radial growth, respectively. The surface roughness was controlled from smooth up to about 37 nm by the radial growth. Our measurements showed that the thermal conductivity of rough surface Si nanowires is significantly lower than that of smooth surface nanowires and decreased with increasing surface roughness even though the diameter of the smooth nanowire was lower than that of the rough nanowires. Considering both nanowires were grown via the same growth mechanism, these outcomes clearly demonstrate that the rough surface induces phonon scattering and reduces thermal conductivity with this nanoscale-hole-free nanowires. Control of roughness induced phonon scattering in Si nanowires holds promise for novel thermoelectric devices with high figures of merit. [ABSTRACT FROM AUTHOR]

We report on bifurcate reactions on the surface of well-aligned SiGe nanowires that enable fabrication of two different coaxial heterostructure nanowires. The SiGe nanowires were grown in a chemical vapor transport process using SiCl gas and Ge powder as a source. After the growth of nanowires, SiCl flow was terminated while O gas flow was introduced under vacuum. On the surface of nanowires was deposited Ge by the vapor from the Ge powder or oxidized into SiO by the O gas. The transition from deposition to oxidation occurred abruptly at 2 torr of O pressure without any intermediate region and enables selectively fabricated Ge/SiGe or SiO/SiGe coaxial heterostructure nanowires. The rate of deposition and oxidation was dominated by interfacial reaction and diffusion of oxygen through the oxide layer, respectively. [ABSTRACT FROM AUTHOR]

Potassium channels allow K+ ions to diffuse through their pores while preventing smaller Na+ ions from permeating. Discrimination between these similar, abundant ions enables these proteins to control electrical and chemical activity in all organisms. Selection occurs at the narrow selectivity filter containing structurally identified K+ binding sites. Selectivity is thought to arise because smaller ions such as Na+ do not bind to these K+ sites in a thermodynamically favorable way. Using the model K+ channel KcsA, we examined how intracellular Na+ and Li+ interact with the pore and the permeant ions using electrophysiology, molecular dynamics simulations and X-ray crystallography. Our results suggest that these small cations have a separate binding site within the K+ selectivity filter. We propose that selective permeation from the intracellular side primarily results from a large energy barrier blocking filter entry for Na+ and Li+ in the presence of K+, not from a difference of binding affinity between ions. [ABSTRACT FROM AUTHOR]

A novel method for ab initio prediction of protein tertiary structures, PROFESY (PROFile Enumerating SYstem), is proposed. This method utilizes the secondary structure prediction information of a query sequence and the fragment assembly procedure based on global optimization. Fifteen-residue-long fragment libraries are constructed using the secondary structure prediction method PREDICT, and fragments in these libraries are assembled to generate full-length chains of a query protein. Tertiary structures of 50 to 100 conformations are obtained by minimizing an energy function for proteins, using the conformational space annealing method that enables one to sample diverse low-lying local minima of the energy. We apply PROFESY for benchmark tests to proteins with known structures to demonstrate its feasibility. In addition, we participated in CASP5 and applied PROFESY to four new-fold targets for blind prediction. The results are quite promising, despite the fact that PROFESY was in its early stages of development. In particular, PROFESY successfully provided us the best model-one structure for the target T0161. Proteins 2004. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

While almost all Si nanostructures, including Si nanowires (SiNWs), Si nanocrystals, and Si nanotrench-like structures on a supra- or sub-10 nm scale exhibit self-limiting oxidative behavior, herein we report full oxidation of SiNWs 5 nm in diameter. We investigated the oxidative behavior of SiNWs with diameters of 5 nm and compared our findings with those for SiNWs with diameters of 30 nm. Single-crystalline SiNWs 5 and 30 nm in diameter were grown by a chemical vapor deposition (CVD) process using Ti as a catalyst. The SiNWs were then oxidized at 600-1000 °C for 30 min to 240 min in O2. The thicknesses of the resulting oxide layers were determined by transmission electron microscopy (TEM). As expected, the SiNWs 30 nm in underwent self-limiting oxidation that was parabolic in nature. However, under the same conditions, the SiNWs 5 nm in diameter underwent full oxidation that was linear in nature. Atomic-scale molecular dynamic simulations revealed that the compressive stress in the oxide layer, which is generated owing to the increase in the volume of the oxide formed, decreased in the case of the SiNWs 5 nm in diameter. It is likely that this decrease in the compressive stress results in a lowering of the energy barrier for the diffusion of oxygen into the oxide layer, leading to the full oxidation of the SiNWs 5 nm in diameter. It is also responsible for the oxidation in the case of SiNWs 5 nm in diameter being interfacial reaction-dominated as opposed to the diffusion dominated-oxidation typical for SiNWs. [ABSTRACT FROM AUTHOR]

Milk fat globule-EGF factor 8 (MFG-E8) is an anti-inflammatory glycoprotein that mediates a wide spectrum of pathophysiological processes. MFG-E8 has been studied as a key regulator of cancer cell invasion, migration, and proliferation in different tissues and organs. However, potential roles of MFG-E8 in the growth and progression of liver cancer have not been investigated to date. Here, we analyzed 33 human hepatocellular carcinoma (HCC) samples and found that levels of MFG-E8 expression were significantly higher in HCC cells than in normal liver tissues. In addition, our in vitro gain-of-function study in three different HCC cell lines revealed that overexpression of MFG-E8 promoted the proliferation and migration of HCC cells, as determined by RT-qPCR, MTT assays, and wound healing analyses. Conversely, an MFG-E8 loss-of function study showed that proliferation capacity was significantly reduced by MFG-E8 knockdown in HCC cells. Additionally, MFG-E8 activity-neutralizing antibodies profoundly inhibited both migration and proliferation of HCC cells, attenuating their tumorigenic properties. These reductions in migration and proliferation were rescued by treatment of HCC cells with recombinant MFG-E8 protein. Furthermore, an in vivo HCC xenograft study showed that the number of proliferating HCC cells and tumor volume/weight were all significantly increased by MFG-E8 overexpression, compared to control mice. These results clearly show that MFG-E8 plays an important role in HCC progression and may provide a basis for future mechanistic studies and new strategies for the treatment of liver cancer. [ABSTRACT FROM AUTHOR]

Free energy perturbation, a method for computing the free energy difference between two states, is often combined with non-Boltzmann biased sampling techniques in order to accelerate the convergence of free energy calculations. Here we present a new extension of the Bennett acceptance ratio (BAR) method by combining it with umbrella sampling (US) along a reaction coordinate in configurational space. In this approach, which we call Bennett acceptance ratio with umbrella sampling (BAR-US), the conditional histogram of energy difference (a mapping of the 3N-dimensional configurational space via a reaction coordinate onto 1D energy difference space) is weighted for marginalization with the associated population density along a reaction coordinate computed by US. This procedure produces marginal histograms of energy difference, from forward and backward simulations, with higher overlap in energy difference space, rendering free energy difference estimations using BAR statistically more reliable. In addition to BAR-US, two histogram analysis methods, termed Bennett overlapping histograms with US (BOH-US) and Bennett-Hummer (linear) least square with US (BHLS-US), are employed as consistency and convergence checks for free energy difference estimation by BAR-US. The proposed methods (BAR-US, BOH-US, and BHLS-US) are applied to a 1-dimensional asymmetric model potential, as has been used previously to test free energy calculations from non-equilibrium processes. We then consider the more stringent test of a 1-dimensional strongly (but linearly) shifted harmonic oscillator, which exhibits no overlap between two states when sampled using unbiased Brownian dynamics. We find that the efficiency of the proposed methods is enhanced over the original Bennett's methods (BAR, BOH, and BHLS) through fast uniform sampling of energy difference space via US in configurational space. We apply the proposed methods to the calculation of the electrostatic contribution to the absolute solvation free energy (excess chemical potential) of water. We then address the controversial issue of ion selectivity in the K+ ion channel, KcsA. We have calculated the relative binding affinity of K+ over Na+ within a binding site of the KcsA channel for which different, though adjacent, K+ and Na+ configurations exist, ideally suited to these US-enhanced methods. Our studies demonstrate that the significant improvements in free energy calculations obtained using the proposed methods can have serious consequences for elucidating biological mechanisms and for the interpretation of experimental data. [ABSTRACT FROM AUTHOR]