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Abstract UPF1 and LIN28A are RNA-binding proteins involved in post-transcriptional regulation and stem cell differentiation. Most studies on UPF1 and LIN28A have focused on the molecular mechanisms of differentiated cells and stem cell differentiation, respectively. We reveal that LIN28A directly interacts with UPF1 before UPF1-UPF2 complexing, thereby reducing UPF1 phosphorylation and inhibiting nonsense-mediated mRNA decay (NMD). We identify the interacting domains of UPF1 and LIN28A; moreover, we develop a peptide that impairs UPF1-LIN28A interaction and augments NMD efficiency. Transcriptome analysis of human pluripotent stem cells (hPSCs) confirms that the levels of NMD targets are significantly regulated by both UPF1 and LIN28A. Inhibiting the UPF1-LIN28A interaction using a CPP-conjugated peptide promotes spontaneous differentiation by repressing the pluripotency of hPSCs during proliferation. Furthermore, the UPF1-LIN28A interaction specifically regulates transcripts involved in ectodermal differentiation. Our study reveals that transcriptome regulation via the UPF1-LIN28A interaction in hPSCs determines cell fate.

Estimating soil moisture from microwave brightness temperature is extremely challenging in densely vegetated areas. The soil moisture retrieved from the Soil Moisture Active Passive (SMAP) measurements tends to be consistently overestimated, sometimes exceeding the saturation level of mineral soils. Therefore, the retrieved soil moisture cannot detect or monitor climate extremes, such as floods and droughts for forests, natural resource management, and climate change research. We hypothesize that the main issue is that the scattering albedo (ω) and the optical depth (τ) are parameterized solely with NDVI (Normalized Difference Vegetation Index), neglecting the polarization characteristics from vegetation structure. This study proposes a weighting factor between scattering and optical thickness, a function of MPDI (Microwave Polarization Difference Index), and applies it to both parameters simultaneously to increase the scattering effect and decrease the attenuation effect in high MPDI. The validation results based on the Climate Reference Network revealed that considering MPDI is critical in reducing soil moisture overestimation errors and obtaining more accurate soil moisture over forested regions. This results in correlation improving from 0.36 to 0.44, a decrease in ubRMSE from 0.179 to 0.125 cm³cm−³, and bias lowering from 0.127 to 0.060 cm³cm−³ in comparison with the SMAP measurements over forested regions. Editor highlights: • Optical depth increases with high NDVI and low MPDI. • Scattering albedo increases with high NDVI and high MPDI. • Increasing scattering albedo decreases brightness temperature in forward simulation. • Decreased brightness temperature in simulation resolved overestimation of SMAP SM. • L-band (1.4 GHz) radiometer measurements can assess forest soil moisture (SM).

Abstract Background The repressor element-1 silencing transcription factor (REST), a master transcriptional repressor, is essential for maintenance, self-renewal, and differentiation in neuroblastoma. An elevated expression of REST is associated with impaired neuronal differentiation, which results in aggressive neuroblastoma formation. E3 ligases are known to regulate REST protein abundance through the 26 S proteasomal degradation pathway in neuroblastoma. However, deubiquitinating enzymes (DUBs), which counteract the function of E3 ligase-mediated REST protein degradation and their impact on neuroblastoma tumorigenesis have remained unexplored. Methods We employed a CRISPR/Cas9 system to perform a genome-wide knockout of ubiquitin-specific proteases (USPs) and used western blot analysis to screen for DUBs that regulate REST protein abundance. The interaction between USP3 and REST was confirmed by immunoprecipitation and Duolink in situ proximity assays. The deubiquitinating effect of USP3 on REST protein degradation, half-life, and neuronal differentiation was validated by immunoprecipitation, in vitro deubiquitination, protein-turnover, and immunostaining assays. The correlation between USP3 and REST expression was assessed using patient neuroblastoma datasets. The USP3 gene knockout in neuroblastoma cells was performed using CRISPR/Cas9, and the clinical relevance of USP3 regulating REST-mediated neuroblastoma tumorigenesis was confirmed by in vitro and in vivo oncogenic experiments. Results We identified a deubiquitinase USP3 that interacts with, stabilizes, and increases the half-life of REST protein by counteracting its ubiquitination in neuroblastoma. An in silico analysis showed a correlation between USP3 and REST in multiple neuroblastoma cell lines and identified USP3 as a prognostic marker for overall survival in neuroblastoma patients. Silencing of USP3 led to a decreased self-renewal capacity and promoted retinoic acid-induced differentiation in neuroblastoma. A loss of USP3 led to attenuation of REST-mediated neuroblastoma tumorigenesis in a mouse xenograft model. Conclusion The findings of this study indicate that USP3 is a critical factor that blocks neuronal differentiation, which can lead to neuroblastoma. We envision that targeting USP3 in neuroblastoma tumors might provide an effective therapeutic differentiation strategy for improved survival rates of neuroblastoma patients.

Background/Aims: This study aimed to determine changes in endoscopist-driven sedation practices 5 years after the first nationwide survey in 2014 by the Korean Society of Gastrointestinal Endoscopy (KSGE). Methods: A 59-item survey covering current practices was electronically mailed to all members of the KSGE in 2019. Results: In total, 955 (12.8%) out of 7,486 questionnaires were returned. A total of 738 (77.7%) out of 955 respondents attended dedicated sedation education programs. The American Society of Anesthesiologists class was recorded by 464 (51.2%) out of 907 respondents. The recording rate was higher in respondents who completed sedation education (p=0.014) and worked in general or tertiary hospitals (p

ERCP has been established as a golden diagnostic and therapeutic modality in various pancreatobiliary diseases, including gallstones and malignancy. On the other hand, ERCP is a relatively invasive procedure with radiation hazards and major complications. Among the major complications, ERCP-related pancreatitis has been reported in more than 14.7% of high-risk patients, which might lead to extended hospitalization and a substantial burden for both patients and physicians. Recent guidelines have defined the high-risk factors for ERCP-related pancreatitis. In addition, several outstanding studies have shown that rectal non-steroidal anti-inflammatory drugs, aggressive hydration with lactated Ringer’s solution, and pancreatic stents can reduce ERCP-related pancreatitis in high-risk patients or all patients. A prevention algorithm for ERCP-related pancreatitis was provided based on advanced research.

Background/Aims This study aimed to determine the current status of facilities, equipment, and personnel for endoscopic sedation from endoscopy units of representative hospitals in South Korea. Methods A questionnaire survey was conducted on 50 qualified endoscopy units accredited by the Korean Society of Gastrointestinal Endoscopy. Results All included endoscopy units had regulations and educational programs regarding sedation training for endoscopists and nursing personnel. There present one assisting nurse during endoscopy in 35 units (70%) and at least two nurses in 12 units (24.0%). All endoscopy units had examination rooms equipped with oxygen supply and suction systems. Endoscopist-directed sedation was performed in 48 units (96.0%). Propofol-based sedation was the most used sedation method. All units had a separate recovery bay. The daily number of patients per bed was greater than 10 in 17 units (34.0%). In 26 (52.0%) units, a single nurse cared for ≥10 patients per day. All the units fulfilled the discharge criteria. Conclusions This study presents data regarding endoscopic sedation clinical practice in 50 endoscopy units in South Korea. This study presents the current status of endoscopic sedation clinical practice in 50 qualified endoscopy units accredited by the KSGE, which provide excellent quality management.

Sedation, defined as the depressed level of consciousness, induced by drug administration, is widely used for gastrointestinal endoscopy to relieve a patient’s anxiety and discomfort. In addition, successful procedure is anticipated with control of unintended movements. Endoscopic sedation, however, cannot be free from the risk of serious adverse events, e.g., cardiopulmonary compromise. Therefore, principles on personnel, facility and equipment, as well as performance itself, should be followed to prevent unfavorable incidents. In this article, sedation guidelines for the Accreditation of Qualified Endoscopy Units, issued by the Korean Society of Gastrointestinal Endoscopy, are presented.

This paper proposes the full simulation model for the electrical analysis of all-electric ship (AES) based on a medium voltage DC power system. The AES has become popular both in the commercial and the military areas due to a low emission, a high fuel consumption efficiency, and a wide applicability. In spite of many advantages, it is complex and difficult to construct the whole system with many mechanical and electrical components onboard. Full electrical analysis is essentially required to simplify the design of the AES, a control and optimization of a ship electric system. The proposed full simulation model of the AES includes the mechanical and the electrical elements by using the MATLAB/Simulink. The mechanical elements are comprised of a steam turbine and a hydrodynamic model of a ship which is adopted by an average value model that is based on the characteristic equation of the mechanical system. The electrical elements are developed by full detailed models which consist of generators, a propulsion motor, a battery, and a power electronics system. In order to design the distribution of the ship, the presented simulation model combined the mechanical and the electrical systems. The consistency of the developed individual models and the integrated AES was verified through the results of the presence or absence of the energy storage system for the speed acceleration and deceleration, loss of prime mover, and full propulsion load rejection.

Abstract Backgrounds Intestinal alkaline phosphatase (IAP) plays important role in gut homeostasis. We aimed to evaluate the expression of endogenous IAP and to assess the clinical course according to the expression of endogenous IAP in patients with Crohn’s disease (CD). Methods A total of 32 consecutive patients (14 males) with CD were included in the study. We measured the level of endogenous iAP in inflamed and noninflamed colonic mucosa. To verify the inflammation status, we measured the level of mRNA for IL-6, TNF-α, and TLR-4. We monitored the clinical courses of patients during follow-up after acquisition of biopsy specimens. Results Median age of patients was 22.5 years (range, 15–49). Median CD activity index (CDAI, range) was 93.7 (22.8~ 154.9). There were colonic involvements in all patients and perianal involvement in 43.8% patients. The mRNA levels of IL-6 (p = 0.005) and TLR-4 (p = 0.013) in inflamed mucosa were significantly higher than those in non-inflamed mucosa. However, there was no difference of expression of TNF-α mRNA (p = 0.345). During a 14-month follow-up (range, 9 months–54 months), there were 19 patients with clinical recurrences. There were 9 patients (9/19, 47.4%) with IAP expression ratio (inflamed to non-inflamed) ≤ 1.0 in patients with clinical recurrence while there was one patient (1/13, 7.7%) with IAP ratio ≤ 1.0 in patients without clinical recurrence (p = 0.024). Conclusion Lower expression of IAP in inflamed mucosa compared to non-inflamed mucosa may be associated with clinical recurrence in patients with CD.

Background/AimsPresence of enhanced mural nodules, which can be visualized using computed tomography (CT), is one of high-risk stigmata in branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs). Conversely, the absence of enhanced mural nodules on preoperative imaging does not exclude malignant risk. The present study aimed to investigate other morphological features as predictors of malignancy in “pure” BD-IPMNs without enhanced mural nodules on CT.Methods : This retrospective study included 180 patients with surgically confirmed “pure” BD-IPMNs of the pancreas and no enhanced mural nodules on preoperative CT. The study was conducted at 15 tertiary referral centers throughout South Korea. Univariate and multivariate analyses were used to identify significant predictors of malignancy.Results : BD-IPMNs with low-grade (n=84) or moderate-grade (n=76) dysplasia were classified as benign; those with high-grade dysplasia (n=8) or invasive carcinoma (n=12) were classified as malignant. The multivariate analysis revealed that cyst size ≥30 mm (odds ratio, 8.6; p=0.001) and main pancreatic duct diameter ≥5 mm (odds ratio, 4.1; p=0.01) were independent risk factors for malignancy in “pure” BD-IPMNs without enhanced mural nodules on CT. Endoscopic ultrasound detected enhanced mural nodules (6/82) that had been missed on CT, and two IPMNs with enhanced mural nodules were malignant.Conclusion : sIn patients with “pure” BD-IPMNs who have no enhanced mural nodules on CT, cyst size ≥30 mm and main pancreatic duct diameter ≥5 mm may be associated with malignancy.

Common bile duct (CBD) stone is a relatively frequent disorder with a prevalence of 10-20% in patients with gallstones. This is also associated with serious complications, including obstructive jaundice, acute suppurative cholangitis, and acute pancreatitis. Early diagnosis and prompt treatment is the most important for managing CBD stones. According to a recent meta-analysis, endoscopic ultrasonography and magnetic resonance cholangiopancreatography have high sensitivity, specificity, and accuracy for the diagnosis of CBD stones. Endoscopic ultrasonography, in particular, has been reported to have higher sensitivity between them. A suggested management algorithm for patients with symptomatic gallstones is based on whether they are at low, intermediate, or high probability of CBD stones. Single-stage laparoscopic CBD exploration and cholecystectomy is superior to endoscopic retrograde cholangiopancreatography (ERCP) plus laparoscopic cholecystectomy with respect to technical success and shorter hospital stay in high risk patients with gallstones and CBD stones, where expertise, operative time, and instruments are available. ERCP plus laparoscopic cholecystectomy is usually performed to treat patients with CBD stones and gallstones in many institutions. Patients at intermediate probability of CBD stones after initial evaluation benefit from additional biliary imaging. Patients with a low probability of CBD stones should undergo cholecystectomy without further evaluation. Endoscopic sphincterotomy and endoscopic papillary balloon dilation in ERCP are the primary methods for dilating the papilla of Vater for endoscopic removal of CBD stones. Endoscopic papillary large balloon dilation is now increasingly performed due to the usefulness in the management of giant or difficult CBD stones. Scheduled repeated ERCP may be considered in patients with high risk of recurrent CBD stones.

Abstract Background Eradication rate for Helicobacter pylori (H. pylori) has decreased due to antibiotic resistance. Therefore, new strategies are needed to enhance H. pylori eradication, especially for H. pylori with high antibiotic resistance. The objective of this study was to evaluate anti-H. pylori activities of constituents from key lime (Citrus aurantifolia) and their possible inhibitory effects on urease activity of H. pylori. Methods Helicobacter pylori strain ATCC 43526 and triple drug resistant (TDR) H. pylori strains were used in this study. Urease activities of H. pylori strains were measured by ammonia colorimetrical quantification using ELISA reader. Minimum inhibitory concentrations were determined by agar dilution method for antibiotics and by modified media dilution method for each constituent of Citrus aurantifolia (C. aurantifolia). Results Citrus aurantifolia extract decreased the number of colonies of H. pylori strain ATCC 43526 and TDR H. pylori stains. An increasing concentration of C. aurantifolia extract attenuated urease activities of H. pylori strain ATCC 43526 and TDR H. pylori strains. Among constituents of C. aurantifolia, citral and 4-hexen-3-one were found to be able to inhibit the growth of H. pylori strain ATCC 43526 and TDR H. pylori strains. Furthermore, citral and 4-hexen-3-one inhibited urease activities of H. pylori strain ATCC 43526 and TDR H. pylori strains in a dose-dependent manner. Conclusion Citrus aurantifolia has antimicrobial effect on TDR H. pylori strains, suggesting that C. aurantifolia might have therapeutic potential to control antibiotic-resistant H. pylori strains that cause eradication failure using other antibiotics.

The three-phase H7 inverter topology installs an additional power semiconductor switch to the positive or negative node of the DC-link for reducing the common-mode voltage (CMV) by disconnecting the inverter from the DC source during the zero-voltage vectors. The conventional CMV reduction method for the three-phase H7 inverter uses modified discontinuous pulse width modulation (MDPWM) and generates a switching signal for the additional switch using logical operations. However, the conventional method is unable to eliminate the CMV for the entire dwell time of the zero-voltage vectors. It only has the effect of reducing the CMV in a limited area of the space vector where the V7 zero voltage vector is applied. Therefore, this paper proposes an optimized modulation method that can reduce the CMV during the entire dwell time of zero-voltage vectors. The proposed method moves the switching patterns by adding an offset voltage to guarantee that only one kind of zero-voltage vector, V7, is applied in the system. It then turns off the seventh switch only during the zero-voltage vector to disconnect the inverter from the DC source. As a result, the CMV and the leakage current are attenuated for the entire dwell time of the zero-voltage vector. Simulation and experimental results confirm the validity of the proposed method.

Low level modular multilevel converter (MMC) is a promising candidate for medium voltage applications such as MVDC (medium voltage DC current) transmission and megawatt machine drives. Unlike high-level MMC using nearest level modulation (NLM), the low-level MMC using the pulse width modulation (PWM) or NLM + PWM is affected by a common mode voltage (CMV) due to a frequent change of a switching state. This CMV causes electromagnetic interference (EMI) noise, common mode current (CMC) and bearing current leading to a reduction in the efficiency and durability of the motor drive system. Therefore, this paper provides a mathematical analysis on how the switching state affects the CMV and proposes three software based CMV reduction algorithms for the low level MMC system. To reflect the characteristic of MMC modulation strategy for upper and lower reference voltage independently, two separate space vectors are used. Based on the analysis, three different CMV reduction algorithms (complete CMV reduction (CCR), DPWM CMV reduction (DCR) and partial CMV reduction (PCR)) are proposed using NLC + PWM modulation strategy. The performance of the proposed CMV reduction algorithms was verified by both simulation and experimental result.

Endoscopic retrograde cholangiopancreatography (ERCP) in post-gastrectomy patients with Billroth II (BII) reconstruction and Roux-en-Y (RY) reconstruction presents a challenge to therapeutic endoscopists. Major difficulties, including intubation to the ampulla of Vater, selective cannulation, and ampullary intervention, must be overcome in these patients. Recent data have shown that device-assisted ERCP allows for high success rates in these patients because various devices are useful for overcoming major difficulties. Therefore, good knowledge of postoperative anatomy and various devices is mandatory before performing ERCP procedures for post-gastrectomy patients.

Virus-induced gene silencing (VIGS) is an effective tool for the study of soybean gene function. Successful VIGS depends on the interaction between virus spread and plant growth, which can be influenced by environmental conditions. Recently, we developed a new VIGS system derived from the Soybean yellow common mosaic virus (SYCMV). Here, we investigated several environmental and developmental factors to improve the efficiency of a SYCMV-based VIGS system to optimize the functional analysis of the soybean. Following SYCMV: Glycine max-phytoene desaturase (GmPDS) infiltration, we investigated the effect of photoperiod, inoculation time, concentration of Agrobacterium inoculm, and growth temperature on VIGS efficiency. In addition, the relative expression of GmPDS between non-silenced and silenced plants was measured by qRT-PCR. We found that gene silencing efficiency was highest at a photoperiod of 16/8 h (light/dark) at a growth temperature of approximately 27°C following syringe infiltration to unrolled unifoliolate leaves in cotyledon stage with a final SYCMV:GmPDS optimal density (OD)₆₀₀ of 2.0. Using this optimized protocol, we achieved high efficiency of GmPDS-silencing in various soybean germplasms including cultivated and wild soybeans. We also confirmed that VIGS occurred in the entire plant, including the root, stem, leaves, and flowers, and could transmit GmPDS to other soybean germplasms via mechanical inoculation. This optimized protocol using a SYCMV-based VIGS system in the soybean should provide a fast and effective method to elucidate gene functions and for use in large-scale screening experiments.

An accurate radiative transfer model (RTM) is essential for the retrieval of soil moisture (SM) from microwave remote sensing data, such as the passive microwave measurements from the Soil Moisture Active Passive (SMAP) mission. This mission delivers soil moisture products based upon L-band brightness temperature data, via retrieval algorithms for surface and root-zone soil moisture, the latter is retrieved using data assimilation and model support. We found that the RTM based on the tau-omega (τ-ω) model can suffer from significant errors over croplands in the simulation of brightness temperature (Tb) (in average between −9.4K and +12.0K for single channel algorithm (SCA); −8K and +9.7K for dual-channel algorithm (DCA)) if the vegetation scattering albedo (omega) is set constant and temporal variations are not considered. In order to reduce this uncertainty, we propose a time-varying parameterization of omega for the widely established zeroth order radiative transfer τ-ω model. The main assumption is that omega can be expressed by a functional relationship between vegetation optical depth (tau) and the Green Vegetation Fraction (GVF). Assuming allometry in the tau-omega relationship, a power-law function was established and it is supported by correlating measurements of tau and GVF. With this relationship, both tau and omega increase during the development of vegetation. The application of the proposed time-varying vegetation scattering albedo results in a consistent improvement for the unbiased root mean square error of 16% for SCA and 15% for DCA. The reduction for positive and negative biases was 45% and 5% for SCA and 26% and 12% for DCA, respectively. This indicates that vegetation dynamics within croplands are better represented by a time-varying single scattering albedo. Based on these results, we anticipate that the time-varying omega within the tau-omega model will help to mitigate potential estimation errors in the current SMAP soil moisture products (SCA and DCA). Furthermore, the improved tau-omega model might serve as a more accurate observation operator for SMAP data assimilation in weather and climate prediction model.

Parkinson’s disease (PD) features nonmotor symptoms such as olfactory dysfunction referred to as hyposmia, an initial sign of disease progression. Metabolic dysfunction can contribute to neurodegenerative diseases, and various xenobiotics and endogenous compounds are also involved in the pathogenesis of PD. Although aerobic exercise was found to induce preservation or improvement in olfactory function in PD patients in a recent study, the exact underlying mechanism for this effect is not clear. We aimed to investigate the influence of an enriched environment (EE) on olfactory dysfunction especially via metabolic pathways related to detoxification enzymes. Eight-month-old transgenic (Tg) PD mice that overexpress human A53T α-synuclein (α-syn) were randomly allocated to an EE or standard conditions for 2 mo. The buried food test showed that EE group had significantly improved olfactory function compared to the control group. Reverse transcription polymerase chain reaction (PCR) and real-time quantitative PCR showed that expression of the detoxification enzymes–– cytochrome P450 family 1 subfamily A member 2 , paraoxonase 1 , alcohol dehydrogenase 1 , UDP glucuronosyltransferase family 2 member A1 complex locus , aldehyde oxidase homolog 2 , and aldehyde glutathione peroxidase 6 ––was significantly increased in the olfactory bulb (OB) of the PD control group, but these enzymes were normalized in the EE group. Immunohistochemical staining of the OB showed that oxidative stress and nitrated α-syn were significantly increased in the control group but decreased in the EE group. In conclusion, we suggest that exposure to an EE decreases both oxidative stress and nitrated α-syn, resulting in normalized detoxification enzymes and amelioration of olfactory dysfunction.

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is commonly used to obtain tissue external to the gastrointestinal tract. EUS-FNA is relatively safe, but occasionally adverse events have been reported. There is scarcity of data on risk factors of adverse events. The aim of this study is to identify risk factors associated with EUS-FNA.In this multicenter case-control study, we retrospectively reviewed 4,097 cases between 2009 and 2012 at 15 hospitals in Korea. Among the patients there were 104 cases (2.5%) who had adverse events of which 12 (0.29%) were severe. We matched 520 controls (1:5 ratios) stratified by hospital to analyze the potential risk factors.The most common adverse events were pancreatitis (45/104, 43.3%) and infection (46/104, 44.2%). Endoscopic retrograde cholangiopancreatography (ERCP) on the same day was a risk factor of all adverse events [OR = 2.41, 95% CI (1.41, 4.12)], pancreatitis [OR = 2.31, 95% CI (1.02, 5.25)], and infection [OR = 2.75, 95% CI (1.31, 5.78)]. More than 15 to-and-fro movements during puncture increased the risk of pancreatitis [OR = 2.30, 95% CI (1.11, 4.77)] and infection [OR = 3.65, 95% CI (1.55, 8.59)]. A higher number of punctures was positively correlated with pancreatitis [OR = 1.34, 95% CI (1.08, 1.67)] but negatively correlated with infection [OR = 0.66, 95% CI (0.48, 0.89)].EUS-FNA is a safe procedure in which serious adverse events are rare. We define some risk factors of adverse events during EUS-FNA, including ERCP on the same day, a higher number of punctures, and more than 15 to-and-fro movements.

We here report that doxycycline, an antibacterial agent, exerts dramatic effects on human embryonic stem and induced pluripotent stem cells (hESC/iPSCs) survival and self-renewal. The survival-promoting effect was also manifest in cultures of neural stem cells (NSCs) derived from hESC/iPSCs. These doxycycline effects are not associated with its antibacterial action, but mediated by direct activation of a PI3K-AKT intracellular signal. These findings indicate doxycycline as a useful supplement for stem cell cultures, facilitating their growth and maintenance.

To reduce the cost of the inverter system in home appliances, a method using a shunt resistor at the DC-link can be substituted for a method using two current sensors at the inverter output. However, the minimum time of the active vector is required to sample the accurate current using a 1-shunt resistor. Therefore, many studies have been conducted investigating current reconstruction methods in the unmeasurable region of the current. The conventional methods using voltage injection have some problems such as high THD (Total Harmonic Distortion) and acoustic noise, because the PWM pattern is shifted. In addition, the current reconstruction is inaccurate in a low modulation region. In this paper, the cause of the noise in conventional methods is analyzed and a simple current reconstruction method based on an average current estimation and a current reference is utilized for reducing acoustic noise. In an immeasurable area, especially a low modulation region, an intermittent PWM shift method is proposed to enhance the accuracy of the reconstructed current. Therefore, a control strategy that combines all of the mentioned methods is implemented for the entire operating range. The effectiveness of the proposed methods is verified through the experimental results and the results of sound measurement in an anechoic chamber are included to compare with the acoustic noise.

The significant growth of machine-to-machine applications for low-power cellular Internet of Things has compelled 3rd Generation Partnership Project to ensure that the future release of long-term evolution can support massive transfer of small, infrequent packets using ultra-low-power and low-cost devices. The 3rd Generation Partnership Project version of machine-to-machine, called “machine-type communication,” is currently being standardized for low-cost machine-type communication operations. In this article, a complete synchronization and cell search procedure is described for machine-type communication devices in long-term evolution systems. Low-complexity algorithms for primary synchronization signal and secondary synchronization signal detection, which requires the highest computational complexity in synchronization and cell search period, are also proposed for low-power machine-type communication devices. Through simulation under long-term evolution-based machine-type communication environments, we show that the proposed methods for primary synchronization signal and secondary synchronization signal detection require six and five times less computational complexity than the conventional methods, respectively, while their performance is similar. The proposed algorithms allow machine-type communication devices in a discontinuous reception cycle to resynchronize quickly with less power when synchronization is lost during a deep sleep period.

Directed methods for differentiating human embryonic stem cells (hESCs) into dopaminergic (DA) precursor cells using stromal cells co-culture systems are already well established. However, not all of the hESCs differentiate into DA precursors using these methods. HSF6, H1, H7, and H9 cells differentiate well into DA precursors, but CHA13 and CHA15 cells hardly differentiate. To overcome this problem, we modified the differentiation system to include a co-culturing step that exposes the cells to noggin early in the differentiation process. This was done using γ-irradiated noggin-overexpressing CF1-mouse embryonic fibroblasts (MEF-noggin) and MS5 stromal cells (MS5-noggin and MS5-sonic hedgehog). After directed differentiation, RT-PCR analyses revealed that engrailed-1 (En-1), Lmx1b, and Nurr1, which are midbrain DA markers, were expressed regardless of differentiation stage. Moreover, tyrosine hydroxylase (Th) and an A9 midbrain-specific DA marker (Girk2) were expressed during differentiation, whereas levels of Oct3/4, an undifferentiated marker, decreased. Immunocytochemical analyses revealed that protein levels of the neuronal markers TH and TuJ1 increased during the final differentiation stage. These results demonstrate that early noggin exposure may play a specific role in the directed differentiation of DA cells from human embryonic stem cells.

Microwave remote sensing techniques are used, among others, for temporally and spatially highly-resolved observations of land-surface properties, e.g., for the management of agricultural productivity and water resource, as well as to improve the performances of numerical weather prediction and climate simulations with soil moisture data. In this context, the effective dielectric constant of the soil is a key variable to quantify the land surface properties. We propose a new approach for the effective dielectric constant of the multiphase soil that is based on an arithmetic average of the dielectric constants of the land-surface components with damping. The results show, on average, better agreement with experimental data than previous approaches. Furthermore, the proposed new model overcomes the theoretical limitation of previous models in the incorporation of non-physical parameters to simulate measured data experimentally with satisfactory accuracy. For microwave remote sensing such as SMAP (Soil Moisture Active Passive), SMOS (Soil Moisture and Ocean Salinity) and AMSR-E (Advanced Microwave Scanning Radiometer for EOS), the physical-based model in our study showed a 23–35% RMSE (root-mean-square error) reduction compared to the most prevalent refractive mixing model in the prediction of the dielectric constant for the real and imaginary part, respectively. Furthermore, in radiowave bands used in portable soil sensors such as TDR (time-domain reflectometer) and GPR (ground-penetrating radar) the new dielectric mixing model reduced RMSE by up to 53% in the prediction of the dielectric constant. We found that the permittivity over the saturation point (porosity of dry soil) has a very different and varying pattern compared to that measured in the unsaturated condition. However, in our study, this pattern was mathematically derived from the same mixing rule applied for the unsaturated condition. It is expected that the new dielectric mixing model might help to improve the accuracy of flood monitoring by satellite.

Cell replacement using stem cells is a promising therapeutic approach to treat degenerative motor neuron (MN) disorders, such as amyotrophic lateral sclerosis and spinal cord injury. Human bone marrow-derived mesenchymal stem cells (hMSCs) are a desirable cell source for autologous cell replacement therapy to treat nervous system injury due to their plasticity, low immunogenicity, and a lower risk of tumor formation than embryonic stem cells. However, hMSCs are inefficient with regards to differentiating into MN-like cells. To solve this limitation, we genetically engineered hMSCs to express MN-associated transcription factors, Olig2 and Hb9, and then treat the hMSCs expressing Olig2 and Hb9 with optimal MN induction medium (MNIM). This method of induction led to higher expression (>30% of total cells) of MN markers. Electrophysiological data revealed that the induced hMSCs had the excitable properties of neurons and were able to form functional connections with muscle fibers in vitro. Furthermore, when the induced hMSCs were transplanted into an injured organotypic rat spinal cord slice culture, an ex vivo model of spinal cord injury, they exhibited characteristics of MNs. The data strongly suggest that induced Olig2/Hb9-expressing hMSCs were clearly reprogrammed and directed toward a MN-like lineage. We propose that methods to induce Olig2 and Hb9, followed by further induction with MNIM have therapeutic potential for autologous cell replacement therapy to treat degenerative MN disorders.

Endoscopic retrograde cholangiopancreatography (ERCP) is a procedure that requires significant experiences and skills and has various procedure-related complications, some of which can be severe and even result in the death of patients. Expanding ERCP availability has the advantage of increasing accessibility for patients. However, ERCP poses a substantial risk if performed without proper quality management. ERCP quality management is essential for both ensuring safe and successful procedures and meeting the social demands for enhanced healthcare competitiveness and quality assurance. To address these concerns, the Korean Pancreatobiliary Association established a task force to develop ERCP quality indicators (QIs) tailored to the Korean medical environment. Key questions for five pre-procedure, three intra-procedure, and four post-procedure measures were formulated based on a literature search related to ERCP QIs and a comprehensive clinical review conducted by experts. The statements and recommendations regarding each QI item were selected through peer review. The developed ERCP QIs were reviewed by external experts based on the latest available evidence at the time of development. These domestically tailored ERCP QIs are expected to contribute considerably to improving ERCP quality in Korea. [ABSTRACT FROM AUTHOR]