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A steel slit damper has been used to enhance the seismic performance of structures with several advantages. The damper can be easily manufactured at a low cost. Furthermore, it can dissipate a significant amount of seismic energy through the stable hysteretic behavior of steel. This study presents a preliminary investigation of the development of a composite steel slit damper that can respond effectively at multiple levels of seismic loading. The performance of the prototype composite steel slit damper is investigated in both experimental and analytical ways. In the experiments, the specimen shows the stable hysteretic response with sufficient ductility, where the multi-phased response is observed in the incremental-amplitude cyclic loading case. Furthermore, a nonlinear numerical analysis that combines both kinematic hardening and isotropic hardening models can reliably describe such characteristics.

Carbon monoxide (CO) is an odorless, colorless, tasteless, extremely flammable, and highly toxic gas. It is produced when there is insufficient oxygen supply during the combustion of carbon to produce carbon dioxide (CO2). CO is produced from operating engines, stoves, or furnaces. CO poisoning occurs when CO accumulates in the bloodstream and can result in severe tissue damage or even death. Many types of CO sensors have been reported, including electrochemical, semiconductor metal-oxide, catalytic combustion, thermal conductivity, and infrared absorption-type for the detection of CO. However, despite their excellent selectivity and sensitivity, issues such as complexity, power consumption, and calibration limit their applications. In this study, a fabricbased colorimetric CO sensor is proposed to address these issues. Potassium disulfitopalladate (II) (K2Pd(SO3)2) is dyed on a polyester fabric as a sensing material for selective CO detection. The sensing characteristics and performance are investigated using optical instruments such as RGB sensor and spectrometer. The sensor shows immediate color change when exposed to CO at a concentration that is even lower than 20 ppm before 2 min. The fast response time of the sensor is attributed to its high porosity to react with CO. This easy-to-fabricate and cost-effective sensor can detect and prevent the leakage of CO simultaneously with high sensitivity and selectivity toward CO.

The debris from exploded buildings can ricochet after colliding with the ground, thus increasing the debris travel distance and danger from any associated impacts or collisions. To reduce this danger, the travel distance of ricocheted debris must be accurately predicted. This study analyzed the change in the travel distance of ricocheted concrete debris relative to changes in the properties of a sand medium. Direct shear tests were conducted to measure the change in internal friction angle as a function of temperature and water content of the sand. Finite element analysis (FEA) was then applied to these variables to predict the speed and angle of the debris after ricochet. The FEA results were compared with results of low-speed ricochet experiments, which employed variable temperature and water content. The travel distance of the debris was calculated using MATLAB, via trajectory equations considering the drag coefficient. As the internal friction angle decreased, the shear stress decreased, leading to deeper penetration of the debris into the sand. As the loss of kinetic energy increased, the velocity and travel distance of the ricocheted debris decreased. Changes in the ricochet velocity and travel distance of the debris, according to changes in the internal friction angle, indicated that the debris was affected by the environment.

As hydrogen (H2) gas is highly reactive and explosive in ambient atmosphere, its prompt detection in industrial areas is imperative to prevent serious accidents. In particular, high-performance H2 sensors that can promptly detect even low-concentrations of H2 gas are necessary for safety. Carbon nanotubes (CNTs) have a large surface area and a high surface-to-volume ratio, and therefore, they are suitable for use as sensing materials in gas sensors. Moreover, gold, platinum, and palladium are known to be excellent catalyst metals that increase reactivity with H2 gas through the catalytic effect referred to as spill-over mechanism. In this study, a CNT felt sensor with a palladium (Pd) layer was fabricated, and its reactivity with H2 was evaluated. The sensitivity of a CNT felt sensor to H2 gas at room temperature was found to improve when coated with Pd layer.

Acute gastrointestinal bleeding (GI bleeding) can range from mild symptoms to life-threatening conditions that require emergency intervention. Therefore, it is important to first identify the high-risk and low-risk patients in the emergency department (ED).This study aimed to investigate the usefulness of a three-hourly interval for determining the lactate clearance, which is shorter than the time interval in previous studies, in order to predict the prognosis early in patients with GI bleeding.This retrospective study involved patients who visited for complaining of GI bleeding symptoms. Initial lactate levels were measured upon arrival at the ED and measured again 3 h later after performing initial resuscitation. And 3-h lactate clearance was calculated. Lactate and 3-h lactate clearance for predicting outcomes were evaluated by the area under the receiver operating characteristic (AUROC) curve.A total of 104 patients were enrolled and 21 patients (20.2%) died in the hospital. Multivariate logistic regression showed that 3-h lactate clearance was a significant predictor of in-hospital mortality. The AUROC of 3-h lactate clearance for predicting in-hospital mortality was 0.756. The sensitivity and specificity were 66.67% and 75.90%. On combining lactate clearance, total bilirubin, and PTT, the AUROC was 0.899 for predicting in-hospital mortality.This study validated that lactate clearance at three-hourly intervals is useful for early prediction of mortality and prognosis in patients with GI bleeding. It is important to perform not only an initial lactate measurement, but also a follow-up lactate measurement after initial resuscitation to check the lactate clearance.

Human papillomavirus (HPV)–related multiphenotypic sinonasal carcinoma (HMSC) is a recently described neoplasm entity that presents only in the sinonasal tract. Histologically, it displays features of both a surface-derived carcinoma and a salivary gland carcinoma, and is associated with high-risk HPV, specifically HPV type 33. Whereas majority of the cases display high-grade histologic features, HMSC paradoxically behaves in a relatively indolent fashion. It is important and meaningful to distinguish HMSC from other histopathologic mimickers as the clinical features and management are distinctive. A 64-year-old woman presented having intermittent left-side epistaxis and progressive nasal obstruction. A well-defined, solitary, friable mass with an irregular surface that easily bled upon contact was found in the posterior part of the left nasal cavity. Endoscopic excision of the tumor which was originated from left nasal septum was done and the tumor was confirmed as HMSC. After surgery, definitive radiotherapy was performed in 28 fractions. HMSC is a histopathological type that has been rarely reported so that we report this case with literature review.

The ferroelectric field-effect transistor (FeFET) is one of the most promising candidates for emerging nonvolatile memory devices owing to its low write energy and high $I_{\mathrm {ON}}/I_{\mathrm {OFF}}$ ratio. For FeFET applications as nonvolatile memory devices, 1FeFET, 1T-1FeFET, 2T-1FeFET, and 3T-1FeFET cells have been proposed. The 1FeFET cell exhibits the highest density but suffers from write disturbance. Although the 1T-1FeFET and 2T-1FeFET cells resolve the write disturbance, they use a write scheme with a negative write voltage ( $V_{\mathrm {W}}$ ), which requires voltage swings of many control signals, leading to a significantly high write energy consumption. The 3T-1FeFET cell uses a write scheme without a negative $V_{\mathrm {W}}$ ; however, it exhibits the largest area overhead. Although the 1T-1FeFET cell resolves the write disturbance with a small area overhead; however, it exhibits high write energy consumption because of the use of a negative $V_{\mathrm {W}}$ . In this paper, to significantly reduce the write energy consumption, we propose a less control signal swing (LCSS) write scheme without using a negative $V_{\mathrm {W}}$ . Simulation results indicate that the worst, average, and best cases of the proposed LCSS write scheme can achieve 35%, 66%, and 96% lower write energy consumption, respectively, than the write scheme with a negative $V_{\mathrm {W}}$ in the 1T-1FeFET cell. We also identify the available sensing schemes for each FeFET cell in the read operation according to the FeFET threshold voltage distribution.

Recently, nonvolatile systems with nonvolatile flip-flops (NVFFs) have gained prominence for their energy efficiency in energy-harvesting devices and battery-operated Internet of Things applications. They are normally-off instantly-on, and thus, can save energy effectively owing to their zero standby power consumption. An NVFF stores the computing state in nonvolatile memories (NVMs) when the power is off. A ferroelectric field-effect transistor (FeFET) is one of the most promising NVMs owing to its high $\text{I}_{\mathrm {on}}/\text{I}_{\mathrm {off}}$ ratio and low write power. Three FeFET-based NVFFs (previous FeFET-out NVFF-1/-2 and FeFET-in NVFF) were recently proposed to improve the area, power, and speed; however, they still have their own problems. Previous FeFET-out NVFF-1 has large area overhead and previous FeFET-out NVFF-2 does not properly perform restore operation. Previous FeFET-in NVFF has a long clock-to-Q delay and high operating energy. This paper introduces two novel FeFET-based NVFFs (proposed FeFET-out and -in NVFFs). Proposed FeFET-out NVFF reduces the large area overhead of previous FeFET-out NVFF-1 and corrects the malfunction in the restore operation of previous FeFET-out NVFF-2. Proposed FeFET-in NVFF achieves a better clock-to-Q delay, operating energy, and area than the previous FeFET-in NVFF. Monte Carlo simulations based on an industry-compatible 10-nm FinFET model are performed for a comparative analysis. Proposed FeFET-out NVFF achieves 17.6% smaller area with slightly higher (6.3%) operating energy and only 0.8% slower clock-to-Q delay than previous FeFET-out NVFF-1. Proposed FeFET-in NVFF achieves 18.9% shorter clock-to-Q and 3.0% smaller operating energy with 8.7% smaller area than the previous FeFET-in NVFF.

Background and Objectives Several studies have assessed the impact of laryngopharyngeal reflux disease (LPRD) on the health-related quality of life (HR-QoL), showing significant impairment of HR-QoL. This study aims to assess the impact of proton pump inhibitor (PPI) treatment of LPRDs to enhance HR-QoL.Subjects and Method We prospectively collected data from LPRD patients from April 2017 to July 2019. Patients who have reflux symptom index (RSI) of ≥13 or reflux finding score (RFS) of ≥7 were enrolled in this study. We assessed HR-QoL using a questionnaire with EORTC QLQ-H&N35, -C30 on the first visit. Patients were treated with PPI (Ilaprazole 20 mg/day) on their visits at 4, 8, and 12 weeks. RSI and RFS were measured at each visit and HR-QoL was reevaluated on the last visit.Results Ninety-five patients completed the 3-months follow-up and were enrolled in this study. Female : male ratio was 71:24 and the mean age was 57.0±11.9 (27-80). The initial RSI and RFS were 16.3±8.8 and 12.6±2.9, respectively, but were changed to 11.1±9.7 and 9.7±2.6 (p

Chronic rhinosinusitis with nasal polyps (CRSwNP) in asthmatic patients has a high recurrence rate even after surgery. For this reason, oral steroids are frequently used, but their long-term use may cause side effects. The purpose of this study is to investigate the long-term effects of budesonide nasal irrigation (BNI) in CRSwNP and asthma. An analysis of 33 patients with CRSwNP and well-controlled asthma, who performed BNI for more than 12 months, was performed. We compared oral steroid and antibiotic dosages as well as nasal endoscopy scores before, and every six months after, BNI. The six-month dosages of oral steroids and antibiotics prescribed were significantly decreased at all time points after BNI compared to before BNI. When the dosages were compared at the time point immediately preceding six months, oral steroid intake decreased significantly until 12 months, and antibiotic intake decreased until 6 months. Furthermore, the endoscopic score decreased significantly until 12 months. The nasal symptom questionnaire score also significantly improved after BNI. Therefore, BNI is considered an effective treatment method that can improve subjective symptoms and objective intranasal findings while reducing oral steroid and antibiotic doses after long-term use in patients with CRSwNP accompanied by asthma.

Palladium-coated multi-walled carbon nanotube (Pd-MWCNT) nanocomposites have been experimentally proven to show highly improved hydrogen (H2) gas detection characteristics at room temperature when compared with single MWCNTs. In this context, we develop an efficient and convenient method for forming nanocomposites by coating Pd nanoparticles on an MWCNT film. Furthermore, we test the applicability of the nanocomposites as sensing materials in detecting H2 gas at room temperature in a reliable and sensitive manner in contrast with ordinary metal-oxidebased gas sensors that operate at high temperatures. We first study the detection efficacy of the Pd-MWCNT film relative to pure MWCNT film. Subsequently, we investigate the Pd-MWCNT sensor’s sensitivity over time for different gas concentrations, the sensor response time, and sensor reproducibility and reliability under various conditions including bending tests. Our sensor exhibits stable reliable detection characteristics and excellent structural flexibility.

Powerful sunlight, a high water temperature, and stagnation in the water flow induce eutrophication in rivers and lakes, which destroys the aquatic ecosystem and threatens the downstream water supply systems. Accordingly, it is very important to perform real-time measurements of nutrients that induce algal growth, especially total phosphorus, to preserve and manage the aquatic ecosystem. To conduct quantitative analysis of the total phosphorus in the aquatic ecosystem, it is essential to perform a pretreatment process and quickly separate the phosphorus, combined with organic and inorganic materials, into a phosphate. In this study, the sandblasting process was used for the physical etching of the wafer, and photocatalytic materials were deposited on the surface with various roughness in order to improve the photocatalytic reaction surface and efficiency. The photocatalytic reaction was applied to combine the pretreated sample with the coloring agent for color development, and the absorbance of the colored sample was analyzed quantitatively to compare and evaluate the characteristics, followed by the surface increase in the photocatalytic materials. In addition, the pretreatment and measurement parts were materialized in a single chip to produce a small and light total phosphorus analysis sensor.

Sox2 is a core transcription factor in embryonic stem cells (ESCs), and O-GlcNAcylation is a type of post-translational modification of nuclear-cytoplasmic proteins. Although both factors play important roles in the maintenance and differentiation of ESCs and the serine 248 (S248) and threonine 258 (T258) residues of Sox2 are modified by O-GlcNAcylation, the function of Sox2 O-GlcNAcylation is unclear. Here, we show that O-GlcNAcylation of Sox2 at T258 regulates mouse ESC self-renewal and early cell fate. ESCs in which wild-type Sox2 was replaced with the Sox2 T258A mutant exhibited reduced self-renewal, whereas ESCs with the Sox2 S248A point mutation did not. ESCs with the Sox2 T258A mutation heterologously introduced using the CRISPR/Cas9 system, designated E14-Sox2TA/WT, also exhibited reduced self-renewal. RNA sequencing analysis under self-renewal conditions showed that upregulated expression of early differentiation genes, rather than a downregulated expression of self-renewal genes, was responsible for the reduced self-renewal of E14-Sox2TA/WT cells. There was a significant decrease in ectodermal tissue and a marked increase in cartilage tissue in E14-Sox2TA/WT-derived teratomas compared with normal E14 ESC-derived teratomas. RNA sequencing of teratomas revealed that genes related to brain development had generally downregulated expression in the E14-Sox2TA/WT-derived teratomas. Our findings using the Sox2 T258A mutant suggest that Sox2 T258 O-GlcNAc has a positive effect on ESC self-renewal and plays an important role in the proper development of ectodermal lineage cells. Overall, our study directly links O-GlcNAcylation and early cell fate decisions., Stem cell development: hold the sugar Cells that can grow into any type of cell, called embryonic stem cells (ESCs), are signaled to stay in stem cell mode (maintain stemness) by addition of a single sugar molecule to Sox2, a regulatory protein coded for by a developmental gene. Sugar modification of Sox2 was known to be involved in maintaining stemness and sometimes implicated in cancer, but the mechanism was poorly understood. When Hyonchol Jang at the National Cancer Center in South Korea and co-workers prevented sugar modification of Sox2 by changing an amino acid at the sugar-binding site, ESCs showed reduced self-renewal. Rather than repressing genes related to stemness, the modification failed to repress developmental genes, permitting cells to grow into other cell types. These results illuminate both the role of Sox2 in cancer and the importance of sugar modification in stemness.

Deployment of small moving cells (SMCs) has been considered in advanced cellular systems, where wireless backhaul links are required between base stations and SMCs. In this paper, we consider signal transmission by means of multiuser beamforming in the wireless backhaul link. We generate the beam weight in an eigen-direction of weighted combination of short- and long-term channel information of the backhaul link. The beam weight can maximize the average signal-to-leakage-plus-noise ratio (SLNR), while providing the transmission robust to SMC mobility. We analyze the performance of the proposed scheme in terms of the average signal-to-interference-plus-noise ratio (SINR) and optimize the transmit power by iterative water-filling. Finally, we verify the performance of the proposed scheme by computer simulation.

We have investigated the effect of the Sr-substitution for Ba on the superconductivity in Yb0.6Ca0.4Ba2-ySryCu3O6 without Ochain forming the so-called Cu(1)O chain in the blocking layer. It has been found that Tc increases with increasing y even though no holes are doped through the Sr2+-substitution for Ba2+. The increase in Tc is because holes doped by the Ca-substitution for Yb are more likely supplied to the superconducting Cu(2)O2 plane than the blocking layer of Cu(1) owing to the contraction of the Cu(2)O2 plane through the substitution of smaller Sr2+ for larger Ba2+. The highest Tconset = 73 K observed for y(Sr) = 0.6 is greatly higher than the previous record of Tconset = 50 K in (RE,Ca)Ba2Cu3O6 (RE: rare-earth element). The reason why it is lower than ∼90 K for REBa2Cu3O7 is the low hole-concentration in the Cu(2)O2 plane.

In this study, pristine carbon nanotubes (CNTs) and the CNTs functionalized through heat treatment were fabricated, and their hydrogen (H2) gas sensing characteristics were evaluated at room temperature. Pristine CNTs exhibited relatively low reactivity toward H2 gas, whereas functionalized CNTs demonstrated linear electrical response characteristics with an increase in the gas concentration due to the presence of functional groups (such as COOH and OH) on the CNT surface, which reduced the activation energy for the adsorption of H2 molecules and provided additional reactive sites. Thus, functionalized CNTs can be potentially utilized in various fields because their operation does not require high-temperature environments (unlike the currently used metal oxide-based H2 sensors), while the power consumption and explosion risks of these materials are easily reduced through a simple heat treatment process.

In this study, experimental variables pertaining to the formation of nano-pillar arrays using p-type silicon were optimized by controlling current density and chamber temperature. Three factors aff...

In this study, we have studied coating method using high reflective White silicon on the whole Zener diode in order to resolve the reducing the luminance of the LED problem caused by the Ze...

Comparative properties of pin-type amorphous silicon (a-Si:H) thin-film solar cells with different PH3 flows for the i-layer and the presence of a buffer layer at the p–i interface were inv...

Carbon monoxide (CO) is an odorless, colorless, tasteless, extremely flammable, and highly toxic gas. It is produced when there is insufficient oxygen supply during the combustion of carbon to produce carbon dioxide (CO₂). CO is produced from operating engines, stoves, or furnaces. CO poisoning occurs when CO accumulates in the bloodstream and can result in severe tissue damage or even death. Many types of CO sensors have been reported, including electrochemical, semiconductor metal-oxide, catalytic combustion, thermal conductivity, and infrared absorption-type for the detection of CO. However, despite their excellent selectivity and sensitivity, issues such as complexity, power consumption, and calibration limit their applications. In this study, a fabricbased colorimetric CO sensor is proposed to address these issues. Potassium disulfitopalladate (II) (K₂Pd(SO₃)₂) is dyed on a polyester fabric as a sensing material for selective CO detection. The sensing characteristics and performance are investigated using optical instruments such as RGB sensor and spectrometer. The sensor shows immediate color change when exposed to CO at a concentration that is even lower than 20 ppm before 2 min. The fast response time of the sensor is attributed to its high porosity to react with CO. This easy-to-fabricate and cost-effective sensor can detect and prevent the leakage of CO simultaneously with high sensitivity and selectivity toward CO.