Defining the Identity and Dynamics of Adult Gastric Isthmus Stem Cells.

The gastric corpus epithelium is the thickest part of the gastrointestinal tract and is rapidly turned over. Several markers have been proposed for gastric corpus stem cells in both isthmus and base regions. However, the identity of isthmus stem cells (IsthSCs) and the interaction between distinct stem cell populations is still under debate. Here, based on unbiased genetic labeling and biophysical modeling, we show that corpus glands are compartmentalized into two independent zones, with slow-cycling stem cells maintaining the base and actively cycling stem cells maintaining the pit-isthmus-neck region through a process of "punctuated" neutral drift dynamics. Independent lineage tracing based on Stmn1 and Ki67 expression confirmed that rapidly cycling IsthSCs maintain the pit-isthmus-neck region. Finally, single-cell RNA sequencing (RNA-seq) analysis is used to define the molecular identity and lineage relationship of a single, cycling, IsthSC population. These observations define the identity and functional behavior of IsthSCs.Wellcome Trust Royal Societ

Characteristics analysis of resonance-based wireless power transfer using magnetic coupling and electric coupling

This study analyses the wireless power transfer of the resonance-based magnetic coupling method and resonance-based electric coupling method and provides information about the characteristics of each. To compare the characteristics of each method, the power transfer efficiency was analysed according to the transfer alignment and misalignment distance between the transceivers. More specifically, they were theoretically analysed through equivalent circuit models, and the results were verified through electromagnetic numerical analysis simulation and the fabrication and experimental results of a wireless power transfer coupler. Although both methods differ according to the coupling method, in terms of power transfer efficiency, it was found that they are determined by the same physical phenomena. Furthermore, in both methods, a null-power point occurred during misalignment between the transceivers. The misalignment distance within which the null-power point occurred is intrinsically determined by the structure of the resonant coupler

Real-Time Monitoring of the Vacuum Degree Based on the Partial Discharge and an Insulation Supplement Design for a Distribution Class Vacuum Interrupter

The internal pressure of a vacuum interrupter (VI) is increased by arc heat, ceramic cracking, gas leakage, and manufacturing defects. Accordingly, the dielectric strength of VI rapidly decreases. To improve the reliability of power transmission, efficient maintenance through the real-time monitoring of the vacuum degree is essential. However, real-time monitoring of the vacuum degree is difficult, and related research is scarce. Additionally, due to the insulation problems of this technology, there are few commercially available products. Therefore, this paper proposes a method for real-time monitoring of the vacuum degree and an insulation supplement design for a distribution class VI. First, dielectric experiments were conducted to identify the section in which the dielectric strength of the VI rapidly decreased according to the vacuum degree. Second, for real-time monitoring of the VI, several factors were proposed through the partial discharge in the VI, while the capacitance characteristics of the VI were calculated to improve the signal of the internal partial discharge. Finally, to supplement the dielectric problems of the solid insulation high voltage apparatus that occur when real-time monitoring technology is applied, the insulation supplement design was performed through the finite element method (FEM)

Shank3-mutant mice lacking exon 9 show altered excitation/inhibition balance, enhanced rearing, and spatial memory deficit

Shank3 is a postsynaptic scaffolding protein implicated in synapse development and autism spectrum disorders. The Shank3 gene is known to produce diverse splice variants whose functions have not been fully explored. In the present study, we generated mice lacking Shank3 exon 9 (Shank3Δ9 mice), and thus missing five out of 10 known Shank3 splice variants containing the N-terminal ankyrin repeat region, including the longest splice variant, Shank3a. Our X-gal staining results revealed that Shank3 proteins encoded by exon 9-containing splice variants are abundant in upper cortical layers, striatum, hippocampus, and thalamus, but not in the olfactory bulb or cerebellum, despite the significant Shank3 mRNA levels in these regions. The hippocampal CA1 region of Shank3Δ9 mice exhibited reduced excitatory transmission at Schaffer collateral synapses and increased frequency of spontaneous inhibitory synaptic events in pyramidal neurons. In contrast, prelimbic layer 2/3 pyramidal neurons in the medial prefrontal cortex displayed decreased frequency of spontaneous inhibitory synaptic events, indicating alterations in the ratio of excitation/inhibition (E/I ratio) in the Shank3Δ9 brain. These mice displayed a mild increase in rearing in a novel environment and mildly impaired spatial memory, but showed normal social interaction and repetitive behavior. These results suggest that ankyrin repeat-containing Shank3 splice variants are important for E/I balance, rearing behavior, and spatial memory. © 2015 FRONTIERS IN CELLULAR NEUROSCIENCE, Lee, Chung, Ha, Lee, Kim, Kim and Kim136361sciescopu

Ordering evolution of block copolymer thin films upon solvent-annealing process

Morphologies of polystyrene-block-poly(2-vinylpyridine) copolymer (S2VP) thin films, which are forming poly(2-vinylpyridine) cylinders in bulk phase, were investigated by atomic force microscopy (AFM) and transmission electron microscopy (TEM) to account for their ordering behavior induced by solvent annealing. Initially, when the copolymer was dissolved in toluene, which is selective solvent for majority polystyrene (PS) blocks, and was spin-coated on Si substrates, dimple-type micellar structures of S2VP were formed. After the film was placed in a solvent-annealing chamber covered with a lid under the existence of chloroform, surface morphologies of S2VP were measured as a function of annealing time. In this study, it was found that the morphologies of S2VP thin film repeated the cycle of the creation and extinction of various morphologies on ordering process. Namely, S2VP exhibited the various transformations between different morphologies, including highly disordered state, cylinders normal to the plane, and cylinders parallel to the plane. Each of the morphologies observed here was employed as a template to synthesize gold (Au) nanoparticles or nanowires. The arrays of Au nano-objects were used to tune a surface plasmon resonance.close

A simple maskless process for the fabrication of vertically aligned high density hematite and graphene/magnetite nanowires

Vertically aligned iron oxide nanowire arrays were successfully synthesized via a cost-efficient maskless top-down approach. High density nanowires are formed by simple oxygen reactive ion etching of an iron-containing polymer film without any artificial mask. Highly crystalline hematite nanowires with a diameter of 38-45 nm and a high aspect ratio of 131 are uniformly produced over large areas after calcination. The high density graphene/magnetite nanostructure created by pyrolyzing iron oxide/organic nanowires with three-dimensional morphology provided highly enhanced Raman scattering with an enhancement factor of up to 7.0 ?? 104 due to trapping of the absorbed light in the three-dimensional graphene forest. Our maskless top-down approach to fabricate iron oxide nanowires offers unique advantages of a solution-based process to easily overcome the limit in the morphology and substrate-dependent properties of nanowire synthesis. This technique may have excellent practical potential as a simple, rapid, and reproducible process for the fabrication of high density and high aspect ratio iron oxide nanowires that are useful in various applications.clos

Fabrication of single-phase SnS film by H-2 annealing of amorphous SnSx prepared by atomic layer deposition

This study evaluated a simple and novel route to fabricate single-phase SnS thin films, consisting of the growth of smooth amorphous SnS2 films by atomic layer deposition at very low temperature using tetrakis(dimethylamino) tin {TDMASn, [(CH3)(2)N](4)Sn} and hydrogen sulfide followed by H-2 annealing at controlled higher temperatures. The properties of the SnS films fabricated by subjecting the amorphous as-grown SnS2 films deposited at 100 degrees C to post-H-2 annealing at 360 degrees C were superior to those of the as-grown SnS films deposited at 200 degrees C in terms of their phase purity, optical band gap, adhesion, and surface roughness. Raman spectroscopy, x-ray diffraction, x-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, and atomic force microscopy consistently showed that single-phase, stoichiometric crystalline (orthorhombic structure) SnS films (Sn/S ratio: similar to 1), without any incorporated sulfur-rich tin sulfides, could be fabricated with a very low surface roughness [root mean square (RMS) roughness: similar to 7 nm] using the proposed scheme. On the other hand, the as-grown SnS film at 200 degrees C still contained a small amount of SnS2 phase and its RMS surface roughness was as high as 16 nm. The optical band gap of the as-grown SnS film was 1.85 eV, whereas that of the annealed SnS film was similar to 1.2 eV, confirming the latter's improved phase purity. The SnS film fabricated by H-2 annealing was a p-type semiconductor with a carrier concentration of similar to 2.3 x 10(16)/cm(3) and a hole mobility of similar to 15 cm(2)/Vs. The present scheme to prepare high-quality SnS films might be useful for fabricating photovoltaic or solar conversion devices. (C) 2017 American Vacuum Society

Fog Computing-Based IoT for Health Monitoring System

Wireless sensor networks (WSNs) are widely used in the area of health informatics. Wireless and wearable sensors have become prevalent devices to monitor patients at risk for chronic diseases. This helps ascertain that patients comply by the treatment plans and also safeguard them during sudden attacks. The amount of data that are gathered from various sensors is numerous. In this paper, we propose to use fog computing to help monitor patients suffering from chronic diseases such that the data are collected and processed in an efficient manner. The main challenge would be to only sort out context-sensitive data that are relevant to the health of the patient. Just having a simple sensor-to-cloud architecture is not viable, and this is where having a fog computing layer makes a difference. This increases the efficiency of the entire system, as it not only reduces the amount of data that is transported back and forth between the cloud and the sensors but also eliminates the risk that a data center failure bears with it. We also analyze the security and deployment issues of this fog computing layer

Ruthenium and ruthenium dioxide thin films deposited by atomic layer deposition using a novel zero-valent metalorganic precursor, (ethylbenzene)(1,3-butadiene)Ru(0), and molecular oxygen

Ruthenium (Ru) and ruthenium dioxide (RuO2) thin films were grown by atomic layer deposition (ALD) by applying a sequential supply of a novel zero-valent metalorganic precursor, (ethylbenzene)(1,3-butadiene)Ru(0) (EBBDRu, C12H16Ru), and molecular oxygen (O-2) at a deposition temperature of 225 degrees C. EBBDRu provided a high vapor pressure of 1.2 Torr at 88 degrees C. In the case of Ru ALD, the growth per cycle (GPC) was similar to 0.06 nm/cycle starting with a slight incubation period of approximately 15 ALD cycles on a thermally grown silicon dioxide initial substrate. A metallic Ru film with high purity and low resistivity (similar to 26 mu Omega cm) was obtained at an ultra-thin thickness of similar to 10 nm. Furthermore, RuO2 thin films were grown controllably by increasing the O-2 pulsing time at a pure O-2 gas flow (with no nitrogen dilution) and at a deposition temperature of 225 degrees C. The GPC in the case of RuO2 ALD was similar to 0.09 nm/cycle and the number of incubation cycles was as low as 6 on a SiO2 starting substrate. Both the Ru and RuO2 thin films exhibited excellent step coverage of similar to 100% in very narrow trenches with 4.5 aspect ratio and a 25 nm top opening. (C) 2015 Elsevier B.V. All rights reserved