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Recent advances in inverter-based distributed energy resources (DERs) allow microgrids to operate in grid-connected and islanded modes with ease. However, determining a steady-state load flow solution of a real-world unbalanced and islanded three-phase microgrid remains a challenge. Existing methods are either unsuitable, labor-intensive or computationally demanding for a long-term analysis of islanded microgrids. To address these issues, we propose a practical solution framework that employs externally-updated system frequency, power quantities, and droop characteristics governing the voltage and phase angle of DERs in every iteration as inputs to an off-the-shelf open-source multi-phase, multi-wire, unbalanced power flow software tool to solve an islanded-microgrid power flow. Using our framework, users only need to implement a set of droop equations and update system variables. The power flow solution is accomplished entirely by an off-the-shelf power flow tool, e.g., OpenDSS. Our proposed framework can model a microgrid of any arbitrary configuration and operating condition. We demonstrate and validate the proposed method’s efficacy by comparing its results with those modeled using a time-domain simulation with PSCAD/EMTDC. Finally, an example of a quasi-static time-series study is presented to better illustrate the application of such a tool.

This work proposes positive- and negative-sequence equivalent circuits of grid-forming inverters for steady-state analysis. The proposed models are especially attractive for performing long-duration voltage regulation analysis and short-circuit studies involving grid-forming inverters. Our proposed equivalent circuit models are based on the inverter’s voltage and current control loops in the $\alpha \beta $ and dq frames. For this reason, they operate according to prescribed control functions and specified impedances (i.e., filter impedance, current limiter block, virtual admittance block, and PI/PR controller block). The equivalent circuit model accuracy is validated by comparing system steady-state voltage and current responses obtained by detailed time-domain models in PSCAD/EMTDC to those by the equivalent circuit models implemented in steady-state load flow program (e.g., OpenDSS). Two distinct control structures implemented in the $\alpha \beta $ and dq frames are used for the validation. Single line-to-ground and line-to-line-to-ground faults are simulated in a small islanded microgrid as well as the IEEE 34-node test feeder. Fault impedances varying from 0 to 5 ohms are simulated. We show that the equivalent models precisely replicate the steady-state response of the detailed time-domain models.

Polyimide is one of the most important high-performance polymers, which is widely used due to its excellent mechanical performance and thermal stability. Unlike the conventional synthetic approach, hydrothermal polymerization enables the synthesis of polyimides without any toxic solvent and catalyst. Herein, we report the synthesis of polyimide-based microparticles (PIMs) through one-pot hydrothermal polymerization using precursors of mellitic acid (MA) and three isomers of phenylenediamine (PDA) (o-, m-, and p-PDA). Interestingly, the chemical composition of PIMs was highly tunable with the choice of the PDA isomers, leading to considerable morphological differences between PIMs. The molecular dynamics simulation and density functional theory calculation of the polymeric segment of the respective PIMs suggested that the relative ratio of amide to imide influenced the rotational freedom of the polymeric chains and number of hydrogen bonds, resulting in the well-defined structures of respective PIMs. Consi...

The performance limits of conventional super engineering plastics with inorganic nanofillers are surpassed by all-organic nanocomposites prepared via in situ S

To date, the application of RNA therapeutics to hematologic malignancies has been challenging owing to the resistance of blood cancer cells against conventional transfection methods. Herein, triple-targeting moiety-functionalized polymeric small interfering RNA (siRNA) nanoparticles were systematically developed for efficient targeted delivery of RNA therapeutics to hematologic cancer cells. Polymeric siRNAs were synthesized using rolling circle transcription and were surface-functionalized with three types of targeting moieties─a natural ligand and two additional combinations of cell-specific antibodies─for tunable targetability. As a proof of concept, the optimization of the hyaluronic acid/antibody conjugation ratio was performed for selective intracellular delivery to various non-Hodgkin's lymphoma (NHL) cell lines (Daudi, Raji, Ramos, and Toledo cells) via receptor-mediated endocytosis. The engineered nanoparticles showed almost 10-fold enhanced NHL-specific intracellular delivery and induced significant in vitro anticancer effects. This multitargeted nanoparticle platform may effectively support the intracellular delivery of polymeric siRNA sequences, and thus promote therapeutic effects in hematopoietic malignancies.

In patients with acute myeloid leukemia (AML) consolidation treatment options are between allogeneic hematopoietic stem cell transplantation (HCT) and chemotherapy, based on disease risk at the time of initial presentation and age. Measurable residual disease (MRD) following induction chemotherapy could be incorporated as a useful parameter for treatment decisions. The present study evaluated treatment outcomes according to the next-generation sequencing (NGS)-based MRD status and the type of consolidation therapy in patients with normal karyotype (NK)-AML. By sequencing 278 paired samples collected at diagnosis and first remission (CR1), we identified 361 mutations in 124 patients at diagnosis and tracked these at CR1. After excluding mutations associated with age-related clonal hematopoiesis, 82 mutations in 50 of the 124 patients (40.3%) were detected at CR1. Survival benefit was observed in favor of allogeneic HCT over chemotherapy consolidation in the MRDpos subgroup with respect to overall survival (HR 0.294, p = 0.003), relapse-free survival (HR 0.376, p = 0.015) and cumulative incidence of relapse (HR 0.279, p = 0.004) in multivariate analysis, but not in the MRDneg subgroup. In summary, these data support allogeneic HCT in NK-AML patients with detectable MRD by NGS in CR1. Randomized clinical trials will be required to confirm this observation.

This work proposes a cost effective with a compact power electronic interface for plug-in electric vehicles (PEVs), which has the ability to achieve the all modes of vehicle operation, including plug-in charging, propulsion (PR) and regenerative braking (RB) for on-board applications. The proposed converter for PEVs has minimum component count as well as step-up and step-down operation ability depending upon the system requirement. The capability of the proposed converter to work in both the modes allows wide range of battery parameters selection, efficient DC-link voltage regulation and offers more flexibility in RB. Moreover, a current sensing based (without voltage sensor) non-linear carrier control (NLCC) technique for power factor correction has also developed in this work. This control scheme improves the reliability and stability of system by reducing the feedback circuitry. A prototype of the proposed charging system is established and analysed to an authenticate the effectiveness of developed system under steady state and dynamic conditions.

This study considers a blunt trailing-edged propeller operating both in a uniform and a nominal wake fields. Experiments are performed in the cavitation tunnel of Hyundai Maritime Research Institute. The effects of propeller rotation speed, tunnel flow speed, and blade sheet cavitation growth on the generation mechanism of the singing propeller are investigated. The cavitation, sound, and vibration characteristics related to the singing phenomena are measured by a hydrophone, a microphone, an accelerometer, and a highspeed digital camera. The natural frequencies of propeller blades are predicted using a finite element method and verified by both contact- and noncontact-type impact hammer tests in air and underwater conditions. The inflow speed and angle of attack for each section of the propeller blades are calculated using the Reynolds-averaged Navier-Stokes equation-based flow analysis. Using a detached eddy simulation, the vortex shedding patterns and their frequencies are calculated. The predicted vortex shedding frequencies are compared with the measured singing frequency and blade natural frequency for determination of consistency. Under cavitation-free regime, the vortex shedding frequencies are predicted for normalized blade radial positions of .8R and .9R. The computed values are close to the two blade natural frequencies and also consistent with the double singing phenomena in the cavitation tunnel test. For fully developed blade sheet cavitation condition, the vortex formation in the wake region is observed to be strongly influenced by the cavitation growth on the pressure side surface. Propeller singing is diminished with the continuous growth of cavitation and is finally locked-off. The significant variation of the flow-induced sound and vibration levels are also observed for the locked-in and the locked-off conditions. The singing occurrence location and frequency under uniform inflow condition are analyzed to investigate the generation mechanism of propeller singing. This study can be applied to the analysis of singing location and its frequency of a propeller operating in the hull wake, which changes the angle of attack according to the propeller rotation angle.

Objective The purpose of this study was to evaluate the impact of time interval between index event and stenting on the periprocedural risk of stenting for symptomatic carotid stenosis and to determine the optimal timing of stenting. Methods This retrospective study included 491 (322 symptomatic [65.6%] and 169 asymptomatic [34.4%]) patients undergoing carotid stenting. The symptomatic patients were categorized into Day 0–3, 4–7, 8–10, 11–14, 15–21, and >21 groups according to the time interval between index event and stenting. Periprocedural (≤30 days) risk for clinical (any neurological deterioration) and radiological (new infarction on postprocedural diffusion-weighted imaging) events of stenting in each time interval versus asymptomatic stenosis was calculated with logistic regression analysis adjusted for confounders, and provided as odds ratio (OR) and 95% confidence interval (CI). Results Overall clinical event rate (4.3%) of stenting for symptomatic carotid stenosis was higher than that for asymptomatic stenosis (1.2%; OR, 3.979 [95% CI, 1.093–14.489]; p=0.036). Stenting in Day 0–3 (13.2%; OR, 10.997 [95% CI, 2.333–51.826]; p=0.002) and Day 4–7 (8.3%; OR, 6.775 [95% CI, 1.382–33.227]; p=0.018) was associated with high risk for clinical events. However, the clinical event rates in stenting after 7 days from index event (Day 8–10, 1.8%; Day 11–14, 2.5%; Day 15–21, 0%; Day >21, 2.9%) were not different from that in stenting for asymptomatic stenosis. Overall radiological event rate (55.6%) in symptomatic stenosis was also higher than that in asymptomatic stenosis (35.5%; OR, 2.274 [95% CI, 1.553–3.352]; p21 : 54.8%; OR, 2.203 [95% CI, 1.342–3.641]; p=0.002). Conclusion This study showed that as stenting was delayed, the periprocedural risk for clinical events decreased. The clinical event risk was high only in stenting within 7 days and comparable with that for asymptomatic stenosis in stenting after 7 days from index event, although the radiological event risk was not affected by stenting timing. Therefore, our results suggest that delayed stenting after 7 days from symptom onset is a safe strategy for symptomatic stenosis.

Background Early cancer detection could identify tumors at a time when outcomes are superior and treatment is less morbid. This prospective case-control sub-study (from NCT02889978 and NCT03085888) assessed the performance of targeted methylation analysis of circulating cell-free DNA (cfDNA) to detect and localize multiple cancer types across all stages at high specificity. Participants and methods The 6689 participants [2482 cancer (>50 cancer types), 4207 non-cancer] were divided into training and validation sets. Plasma cfDNA underwent bisulfite sequencing targeting a panel of >100 000 informative methylation regions. A classifier was developed and validated for cancer detection and tissue of origin (TOO) localization. Results Performance was consistent in training and validation sets. In validation, specificity was 99.3% [95% confidence interval (CI): 98.3% to 99.8%; 0.7% false-positive rate (FPR)]. Stage I–III sensitivity was 67.3% (CI: 60.7% to 73.3%) in a pre-specified set of 12 cancer types (anus, bladder, colon/rectum, esophagus, head and neck, liver/bile-duct, lung, lymphoma, ovary, pancreas, plasma cell neoplasm, stomach), which account for ∼63% of US cancer deaths annually, and was 43.9% (CI: 39.4% to 48.5%) in all cancer types. Detection increased with increasing stage: in the pre-specified cancer types sensitivity was 39% (CI: 27% to 52%) in stage I, 69% (CI: 56% to 80%) in stage II, 83% (CI: 75% to 90%) in stage III, and 92% (CI: 86% to 96%) in stage IV. In all cancer types sensitivity was 18% (CI: 13% to 25%) in stage I, 43% (CI: 35% to 51%) in stage II, 81% (CI: 73% to 87%) in stage III, and 93% (CI: 87% to 96%) in stage IV. TOO was predicted in 96% of samples with cancer-like signal; of those, the TOO localization was accurate in 93%. Conclusions cfDNA sequencing leveraging informative methylation patterns detected more than 50 cancer types across stages. Considering the potential value of early detection in deadly malignancies, further evaluation of this test is justified in prospective population-level studies.

A novel integrated converter for electric vehicles (EVs) is proposed in this article. For battery-charging operation, the proposed converter system enables a complementary deployment of the utility grid and a solar photovoltaic (PV) system. Since both sources (acting one at a time) utilize the same converter, the developed charging system, therefore, has a smaller number of components. In addition, an inductor voltage detection (IVD) technique has been incorporated to correct the power factor (PF) in continuous conduction mode (CCM), which eliminates the need for a current sensor for PF correction (PFC). The proposed system operates for all the modes required for an EV, e.g., charging, propulsion (PRN), and regenerative braking (RBG). In charging mode (with either grid or solar PV), the proposed system operates as an isolated secondary ended primary inductance converter (SEPIC) converter. In PRN and RBG modes, it operates as a boost converter and a buck converter, respectively. Details of all these modes are described in the article, along with the design of the components. In addition, results of simulation and experimental studies are presented for a 1-kW setup based on the proposed configuration. A comparison with other topologies shows the technoeconomic competence of the proposed system.

Multifunctional cellulose membranes were developed from A4-sized printing paper via chemical modification. A4 paper is a widely used and easily accessible product with high cellulose content. Inspired by cellulose chemistry, we report a simple modification of the A4 paper, converting it from a common office supply to a user-modifiable functionalized cellulose membrane for practical applications. The hydroxyl groups of cellulose enable a facile tuning of its internal structure and polarity via chemical modification. In addition, the functionalized cellulose membrane has more stable mechanical strength compared to commercial cellulose-based filtration membranes. As a proof-of-concept, we demonstrate the separation of a water/oil mixture using the functionalized A4 membrane; we have extended this idea to origami-assisted membrane applications. Finally, this versatile A4 paper chemistry may offer a promising strategy for the development of functional membranes.

The performance limits of conventional super engineering plastics with inorganic nanofillers are surpassed by all-organic nanocomposites prepared via in situ SNAr polymerization of polysulfone (PSU...

Residential electricity loads highly fluctuate which makes it challenging to predict and estimate changes and anomalies. This article studies the statistical distribution of the maximum load of residential settlements and proposes a new model that is more reliable than conventional methods to predict extreme events in residential electricity consumption. Specially, a multimodal Tracy-Widom distribution is proposed to characterize the maximum residential electricity consumption data. We also propose a numerical method to approximate the density function of the multimodal Tracy-Widom distribution as opposed to the conventional approach in the literature, where a multimodal normal distribution is utilized. A simulated electricity consumption data set is used to test and validate the proposed methods. The results demonstrate that the multimodal Tracy-Widom distribution is more accurate than conventional methods in modeling residential electricity consumption data. In addition, the numerical results show that residential electricity consumption behavior is determined by certain socioeconomic factors for which correlations with household electricity consumption exist.

In this paper, we propose a floating-gate-based synaptic transistor with two independent control gates that implement both offline and online learning. Unlike previous research on double-gated synaptic transistors, the proposed device is capable of online learning without facing a fan-out problem. Basic operation of the device was verified and a program/erase scheme based on Fowler-Northeim tunneling is suggested for the multi-conductance utilization of the synaptic device. With the proposed P/E scheme, an offline-trained single-layered hardware-based spiking neural network was simulated for MNIST classification, resulting in 87.37% classification accuracy with 10% conductance variation. To alleviate this performance degradation, the online learning method is applied on the offline-trained SNN by reusing 3,000 training images. The effectiveness of the proposed method is also verified under existence of the synaptic weight variance. As a result, up to 86.89% of the performance degradation is alleviated.

New genome sequencing technologies with enhanced diagnostic efficiency have emerged. Rapid and timely diagnosis of treatable rare genetic diseases can alter their medical management and clinical course. However, multiple factors, including ethical issues, must be considered. We designed a targeted sequencing platform to avoid ethical issues and reduce the turnaround time.We designed an automated sequencing platform using dried blood spot samples and a NEOseq_ACTION panel comprising 254 genes associated with Mendelian diseases having curable or manageable treatment options. Retrospective validation was performed using data from 24 genetically and biochemically confirmed patients. Prospective validation was performed using data from 111 patients with suspected actionable genetic diseases.In prospective clinical validation, 13.5% patients presented with medically actionable diseases, including short- or medium-chain acyl-CoA dehydrogenase deficiencies (N=6), hyperphenylalaninemia (N=2), mucopolysaccharidosis type IVA (N=1), alpha thalassemia (N=1), 3-methylcrotonyl-CoA carboxylase 2 deficiency (N=1), propionic acidemia (N=1), glycogen storage disease, type IX(a) (N=1), congenital myasthenic syndrome (N=1), and citrullinemia, type II (N=1). Using the automated analytic pipeline, the turnaround time from blood collection to result reporting was4 days.This pilot study evaluated the possibility of rapid and timely diagnosis of treatable rare genetic diseases using a panel designed by a multidisciplinary team. The automated analytic pipeline maximized the clinical utility of rapid targeted sequencing for medically actionable genes, providing a strategy for appropriate and timely treatment of rare genetic diseases.

Quantum dot light emitting diodes (QD-LEDs) have high potential to be used in next-generation displays. The main challenge in the commercialisation of QD-LEDs is the improvement of the efficiency and stability of blue QD-LEDs. The most promising emitter for blue QD-LEDs is ZnTeSe QD, however it is concerned that tellurium causes spectral broadening and efficiency drop. In this work, we demonstrate the effect of Te clusters on the electronic structures of blue ZnTeSe QDs through first principle calculation. The photo dynamics at the ensemble and single dot level show that the lifting of hole-state degeneracy in Te-doped structures causes slow relaxation and peak emission shift. Furthermore, the strong confinement of hole wave functions in Te clusters improves the efficiency and stability of QD-LEDs by suppressing QD luminescence quenching under electrical bias. The understanding of the correlation between the photophysical nature of Te-doped QDs and device performance can provide a basis for designing blue-emitting QD structures that are suitable for practical QD-LEDs.

Secondary-type mutations (STMs), namely SRSF2, SF3B1, U2AF1, ZRSR2, ASXL1, EZH2, BCOR, and STAG2, are more frequently detected in secondary acute myeloid leukemia (AML) than in de novo AML. Whether de novo AML with STMs should be differently managed is, however, unclear. In 394 patients diagnosed with de novo AML who had a normal karyotype, the genetic profiling via targeted deep sequencing of 45 genes revealed 59 patients carrying STMs (STM

Background: Serum asialo α1-acid gycoprotein (AsAGP) is a novel biomarker specific to liver fibrosis. Aim: To evaluate the diagnostic efficacy of serum AsAGP levels in classifying the severity of liver fibrosis and differentiating liver cirrhosis (LC) in patients with chronic hepatitis B (CHB) from healthy controls. Methods: Overall, 206 subjects were prospectively enrolled. LC was diagnosed based on liver stiffness levels (>11 kPa) measured using transient elastography. Serum AsAGP levels were measured using an antibody-lectin sandwich immunoassay. We investigated the diagnostic performance by comparing serum AsAGP levels among healthy control, CHB, and CHB with LC groups. Sensitivity, specificity, and optimal AsAGP cut-off values were also calculated. Results: Serum AsAGP levels were significantly different between healthy controls, CHB patients, and CHB patients with LC (1.04 ± 0.31 µg/mL, 1.12 ± 0.34 µg/mL, 1.51 ± 0.43 µg/mL respectively; p < 0.001). Serum AsAGP levels positively correlated with liver stiffness (r = 0.46, p < 0.001). AUROC of healthy control versus CHB with LC was 0.821 (p < 0.001, optimal cut-off 1.036 µg/mL). AUROC of healthy control versus CHB was 0.624 (p = 0.049, optimal cut-off level 0.934 µg/mL). AUROC of CHB versus CHB with LC was 0.765, (p < 0.001, optimal cut-off 1.260 µg/mL). Conclusions: Serum AsAGP levels in CHB patients with LC were significantly higher than those in healthy controls and CHB patients. AsAGP levels showed good diagnostic performance in predicting advanced fibrosis and cirrhosis, which suggests a potential role as a biomarker for predicting the progression of liver disease in CHB.

Despite its abundance, water is not widely used as a medium for organic reactions. However, under geothermal conditions, water exhibits unique physicochemical properties, such as viscosity and a dielectric constant, and the ionic product become similar to those of common organic solvents. We have synthesized highly crystalline polyimide-based covalent organic frameworks (PICs) under geomimetic hydrothermal conditions. By exploiting triphenylene-2,3,6,7,10,11-hexacarboxylic acid in combination with various aromatic diamines, PICs with various pore dimensions and crystallinities were synthesized. XRD, FT-IR, and DFT calculations revealed that the solubility of the oligomeric intermediates under hydrothermal conditions affected the stacking structures of the crystalline PICs. Furthermore, the synthesized PICs demonstrate promising potential as an anode material in lithium-ion batteries owing to its unique redox-active properties and high surface area.

Internal tandem duplication of the Feline McDonough Sarcoma (FMS)-like tyrosine kinase 3 (

Simple Summary Approximately 50–60% of patients with chronic myeloid leukemia (CML) achieve a stable deep molecular response (DMR) after tyrosine kinase inhibitor (TKI) therapy. The achievement of DMR is a prerequisite for treatment-free remission. Repurposing statins is a straightforward strategy for enhancing molecular response in CML treatment. Second-generation TKIs have been reported to exhibit cardiovascular toxicity. Thus, statins have been widely prescribed for patients with CML undergoing second-generation TKI therapy for modifying cardiovascular risk factors, such as hyperlipidemia. Furthermore, the results of this study support the therapeutic benefit of the concomitant use of statins in TKI therapy for patients with CML. Additionally, the potential additive effects of statins and TKIs enhance the DMR rate in patients with CML, rendering these effects clinically relevant in these patients. In particular, this combination is a strong candidate for the achievement of DMR in patients with CML who have not achieved DMR with TKI therapy alone. Abstract Previous studies have suggested that statins can be repurposed for cancer treatment. However, the therapeutic efficacy of statins in chronic myeloid leukemia (CML) has not yet been demonstrated. In this study, we retrospectively evaluated the outcomes of 408 CML patients who underwent imatinib therapy. The deep molecular response rates in patients treated with the statin/TKI combination were significantly higher than those in patients treated with TKI alone (p = 0.0016). The statin/TKI combination exerted potent cytotoxic effects against wild-type and ABL1 mutant CML, BaF3, and K562/T315I mutant cells. Furthermore, the statin/TKI combination additively inhibited the colony-forming capacity of murine CML-KLS+ cells in vitro. In addition, we examined the additive growth-inhibitory effects of the statin/tyrosine kinase inhibitor (TKI) combination against CML patient-derived CD34+ cells. The growth-inhibitory effects of the statin/imatinib combination against CD34+/CML primary cells were higher than those against CD34+/Norm cells (p = 0.005), suggesting that the combination of rosuvastatin and imatinib exerted growth-inhibitory effects against CML CD34+ cells, but not against normal CD34+ cells. Furthermore, results from RNA sequencing of control and statin-treated cells suggested that statins inhibited c-Myc-mediated and hematopoietic cell differentiation pathways. Thus, statins can be potentially repurposed to improve treatment outcomes in CML patients when combined with TKI therapy.

After the 2016 Gyeongju Earthquake (MW 5.5) in SE Korea, the NNE‒SSW-striking Yangsan Fault (YF) seismicity has emerged as a significant scientific issue and hazard. Despite previous stu...

In this paper, we investigated the dependence of minority carrier lifetime on dual gate FBFET. Generally, depending on the channel condition or trap density, the lifetime of minority carrier can be degraded. Since the potential barrier lowering through the accumulated carriers is essential for positive feedback, the deterioration of lifetime can make a critical influence on the operation of device. Therefore, we verified the tendency of threshold voltage according to carrier lifetime and channel length. Through the comparison with p-n diode and FBFET, we drew the relation between lifetime and threshold voltage. As a result, it has been confirmed that the device with significantly deteriorated lifetime or the device with extremely long channel does not effectively generate feedback and loses its steep switching characteristics.