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The electrical stability of molybdenum disulfide (MoS2) transistors is crucial for their use in various applications. However, it is tricky to evaluate the inherent stability of MoS2 transistors because it is highly dependent on environmental conditions during measurement such as humidity, light, and electrical factors. We studied the threshold voltage instability under negative bias stress at a variety of temperatures in a vacuum and in the dark to eliminate any environmental effects. In particular, the measurement of transfer curves under stress is minimized in order to study the inherent instability of MoS2 transistors, even though the measurement of transfer curves is normally indispensable to check for the evolution of electrical instability. MoS2 transistors have high average effective energy when compared to conventional amorphous Si and oxide semiconductor transistors, which allows for adequate operation at high temperatures. (© 2014 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Sensors that detect and discriminate external mechanical forces are a principal component in the development of electronic tactile systems that can mimic the multifunctional properties of human skin. This study demonstrates a pyramid‐plug structure for highly sensitive tactile sensors that enables them to detect pressure, shear force, and torsion. The device is composed of pyramid‐patterned ionic gel inspired by neural mechanoreceptors and engraved electrodes. Based on a pyramid‐plug structure, the deformation mechanism differs between different types of external mechanical loadings. The sensor provides the high sensitivities of 1.93 kPa−1, 29.88 N−1, and 3.39 (N cm)−1, and a wide range of detection for tactile daily activity. Moreover, this tactile sensor could work through either of the two transduction methods (capacitive transduction and piezoresistive transduction). It is shown that this tactile sensor can be used to monitor changes in electrical signals ranging from those caused by human breathing to those caused by arbitrary multiplex human touching. A pyramid‐plug structure for highly sensitive tactile sensors that enables them to detect pressure, shear force, and torsion is demonstrated. This tactile sensor could work by each of the two transduction methods. The sensor provides the high sensitivities of 1.93 kPa−1, 29.88 N−1, and 3.39 (N cm)−1, and a wide range of detection for tactile daily activity. [ABSTRACT FROM AUTHOR]

Background: Evogliptin tartrate inhibits dipeptidyl peptidase-4 (DPP-4), boosting glucagon-like peptide 1 (GLP-1) secretion and improving insulin release and glucose tolerance, while also exerting anti-inflammatory effects. We investigated its anti-inflammatory and analgesic effects. Methods: Forty male Sprague Dawley rats were divided into (N = 10 in each): (1) naïve, (2) complete Freund's adjuvant (CFA) inflammation + evogliptin tartrate (once for 10 mg/kg) (CFAE), (3) CFA + vehicle (same volume with normal saline with evogliptin tartrate/once) (CFAV), and (4) CFA + indomethacin (5 mg/mL/kg/1 time) (CFAI) groups. CFA was injected subcutaneously into rat plantar regions, and medications (evogliptin tartrate, vehicle, and indomethacin) were administered orally for 5 days. Post treatment, blood from the heart and plantar inflammatory tissue were collected to assess inflammatory cytokines. Evogliptin tartrate effects on controlling inflammation and pain were evaluated by measuring rat plantar paw thickness, paw withdrawal threshold, dorsal root ganglion (DRG) resting membrane potential, DRG action potential firing, and cytokine (TNF-α and IL-1β) levels. Results: Compared with the naïve group, plantar paw thickness, cytokine (TNF-α and IL-1β) levels, DRG resting membrane potential, and DRG action potential firing increased, whereas the paw withdrawal threshold decreased in all CFA groups. However, CFAE and CFAI rats showed recovery. The degree of CFAE recovery resembled that observed in the CFAI group. Conclusions: Evogliptin tartrate mirrored the anti-inflammatory pain relief of indomethacin. We aim to broaden its use as an anti-inflammatory drug or pain relief drug. [ABSTRACT FROM AUTHOR]

This paper deals with the shape design of the iron-core of a hybrid EMS (electro-magnetic suspension) system. A proto-type hybrid EMS system was developed by Yonsei University in 2010 refid="ref1"/ , refid="ref2"/. It is the first step of study on fundamental technology for advanced railroad systems development. The hybrid EMS system requires cooling systems because it uses superconducting magnets refid="ref3"/ , refid="ref4"/. These cooling systems can influence costs to making and operating the hybrid EMS system. Therefore, a study to reduce the number of cooling systems needs to be carried out in order to economically commercialize the hybrid EMS system. In this paper, a method that reduces the number of cooling systems of the hybrid EMS system was proposed. To achieve this, a small-scale iron-core and coils assembly was fabricated. Using this system, characteristics of levitation force according to the structure of the iron-core was evaluated. Also, numerical analysis using the FEM tool in order to evaluate the levitation force and net force of a full-scale model was performed. This paper can be expected to suggest useful data for the design of a hybrid EMS system. [ABSTRACT FROM PUBLISHER]

High temperature superconductor (HTS) is a promising material as current leads for large current applications, because it has zero resistance. However, a single HTS tape has limitation on the capacity of current rating due to the critical current of the HTS tape. Therefore, stacking or parallel structure of the HTS tapes is inevitable in high temperature superconducting current leads (HTSCLs) for large current application. In this paper, several stacking methods with respect to the shape of the current terminal and the structure of the HTS tape are studied and the characteristics of the stacked samples are investigated by experimental analysis. The critical currents of the HTS modules were measured and the conductive heat leakage of a stabilizer layer was calculated. From this analysis, the characteristics of the current distribution and decrease in the critical current of HTS modules with respect to the shape of the current terminal were obtained. Based on the results, the required stacking number of the HTS tapes for certain operating current HTSCLs can be calculated. [ABSTRACT FROM AUTHOR]

To design a large scale superconducting fault current limiter (SFCL) for power grids, a single long-length YBCO coated conductor (CC) wire is preferred. However this single YBCO CC wire can cause a problem of unequal voltage distribution between the parts on the long wire at quench by the faults. Inhomogeneous critical current of the YBCO CCs in the SFCL is a possibility. Furthermore, sub-cooled liquid nitrogen (LN2) condition is usually used to increase current capacity of the SFCL. However, this sub-cooled condition can worsen the inhomogeneity between the YBCO CCs. Therefore, it is important to understand the relation between the unequal voltage distribution and the inhomogeneous critical currents in the single long length YBCO CC. In this paper, experiments with the same single YBCO CC wire were conducted in various temperature conditions, LN2 and sub-cooled LN2. In both experiments, the critical currents and voltage distributions generated by faults at short-circuit tests were measured. It was observed that the inhomogeneous condition impacts on the unequal voltage distribution. [ABSTRACT FROM AUTHOR]

Levels of amyloid-β (Aβ) and tau peptides in brain have been associated with Alzheimer disease (AD). The current study investigated the abilities of plasma Aβ42 and total-tau (t-tau) levels in predicting cognitive decline in subjects with amnestic mild cognitive impairment (MCI). Plasma Aβ42 and t-tau levels were quantified in 22 participants with amnestic MCI through immunomagnetic reduction (IMR) assay at baseline. The cognitive performance of participants was measured through neuropsychological tests at baseline and annual follow-up (average follow-up period of 1.5 years). The predictive value of plasma Aβ42 and t-tau for cognitive status was evaluated. We found that higher levels of Aβ42 and t-tau are associated with lower episodic verbal memory performance at baseline and cognitive decline over the course of follow-up. While Aβ42 or t-tau alone had moderate-to-high discriminatory value in the identification of future cognitive decline, the product of Aβ42 and t-tau offered greater differential value. These preliminary results might suggest that high levels of plasma Aβ42 and t-tau in amnestic MCI are associated with later cognitive decline. A further replication with a larger sample over a longer time period to validate and determine their long-term predictive value is warranted. [ABSTRACT FROM AUTHOR]