This Letter proposes a novel technique for automatic position offset calibration for permanent-magnet synchronous machine (PMSM) drives. Contrary to existing methods, the proposed technique estimates ...and compensates for the position offset without using machine true parameters or signal injection, which is possible under the condition of zero-current control at high enough speed where parameter-dependent terms are eliminated. To achieve this condition using uncertain parameters, speed control with absolute value feedback and model-free current control are devised. Additionally, under this condition, not only the misalignment of the position sensor but also the sensor delay can be considered as the position offset, which improves the accuracy of the calibration. The proposed approach will be verified by experimental results.
•Recent progress in MXene based supercapacitive energy storage is reviewed.•Top-down and bottom-up MXene synthesis methods are discussed.•Unique properties of MXenes have been reviewed.•Charge ...storage mechanism of various MXene based supercapacitors are dsicused.
In the past few decades, with the advancement of technology, there has been an increasing demand for high-capacity energy storage devices having durability, low production cost, and flexibility. MXene, a layered 2D transition metal carbide, nitride or carbonitride, exfoliated from its parent MAX phase by selective chemical etching of covalently bonded A layer has become the most emerging material today for energy storage applications. The 2D layered structure, atomic layer thickness, high conductivity, tunable surface functional groups, superior hydrophilicity, good mechanical properties, excellent electrochemical nature, flexibility, and the ease of preparation of MXene has made it the most demanding material today among 2D families. Starting from gas and biosensors, water purification, water splitting, photo and electrocatalysis, transparent conductors in electronics, antibacterial film, electromagnetic interference shielding, and in batteries and supercapacitors, MXene have a wide range of applications. The special properties of MXene have made scientists work on its further theoretical and experimental developments. This article mainly reviews the recent advances of MXene for fabricating durable, pliable, and highly efficient electrochemical energy storage devices using supercapacitors as its power source. The structure of MXene, different synthesis methods, and their unique properties have been deeply studied, as well as the effect of various factors like size and shape of MXene sheets, design of electrode architecture, nature of electrolyte, etc. on the electrochemical performance and charge storage mechanism of MXene based supercapacitors have been emphasized. This article also throws light on state-of-the-art recent progress in MXene composite-based supercapacitors. Finally, its challenges and future advances have been discussed.
Objective
To compare the efficacy of two types of progestogen therapy for preventing preterm birth (PTB) and to review the relevant literature.
Design
A multicentre, randomised, open‐label, ...equivalence trial and a meta‐analysis.
Setting
Tertiary referral hospitals in South Korea.
Population
Pregnant women with a history of spontaneous PTB or short cervical length (<25 mm).
Methods
Eligible women were screened and randomised at 16‒22 weeks of gestation to receive either 200 mg of vaginal micronised progesterone daily (vaginal group) or an intramuscular injection of 250 mg 17α‐hydroxyprogesterone caproate weekly (IM group). Stratified randomisation was carried out according to participating centres and indications for progestogen therapy. This trial was registered at ClinicalTrials.gov (NCT02304237).
Main outcome measure
Preterm birth (PTB) before 37 weeks of gestation.
Results
A total of 266 women were randomly assigned and a total of 247 women (119 and 128 women in the vaginal and IM groups, respectively) were available for the intention‐to‐treat analysis. Risks of PTB before 37 weeks of gestation did not significantly differ between the two groups (22.7 versus 25.8%, P = 0.571). The difference in PTB risk between the two groups was 3.1% (95% CI −7.6 to 13.8%), which was within the equivalence margin of 15%. The meta‐analysis results showed no significant differences in the risk of PTB between the vaginal and IM progestogen treatments.
Conclusion
Compared with vaginal progesterone, treatment with intramuscular progestin might increase the risk of PTB before 37 weeks of gestation by as much as 13.8%, or reduce the risk by as much as 7.6%, in women with a history of spontaneous PTB or with short cervical length.
Tweetable
Vaginal and intramuscular progestogen showed equivalent efficacy for preventing preterm birth before 37 weeks of gestation.
Tweetable
Vaginal and intramuscular progestogen showed equivalent efficacy for preventing preterm birth before 37 weeks of gestation.
RNA-sequencing (RNA-seq) is a powerful technique to investigate the complexity of gene expression in the human brain. We used RNA-seq to survey the brain transcriptome in high-quality postmortem ...dorsolateral prefrontal cortex from 11 individuals diagnosed with bipolar disorder (BD) and from 11 age- and gender-matched controls. Deep sequencing was performed, with over 350 million reads per specimen. At a false discovery rate of <5%, we detected five differentially expressed (DE) genes and 12 DE transcripts, most of which have not been previously implicated in BD. Among these, Prominin 1/CD133 and ATP-binding cassette-sub-family G-member2 (ABCG2) have important roles in neuroplasticity. We also show for the first time differential expression of long noncoding RNAs (lncRNAs) in BD. DE transcripts include those of serine/arginine-rich splicing factor 5 (SRSF5) and regulatory factor X4 (RFX4), which along with lncRNAs have a role in mammalian circadian rhythms. The DE genes were significantly enriched for several Gene Ontology categories. Of these, genes involved with GTPase binding were also enriched for BD-associated SNPs from previous genome-wide association studies, suggesting that differential expression of these genes is not simply a consequence of BD or its treatment. Many of these findings were replicated by microarray in an independent sample of 60 cases and controls. These results highlight common pathways for inherited and non-inherited influences on disease risk that may constitute good targets for novel therapies.
Summary
Background
A proportion of chronic hepatitis B (CHB) patients are diagnosed with advanced hepatocellular carcinoma (HCC) despite regular surveillance.
Aims
To determine predictors for HCC ...detection failure in CHB patients who underwent regular surveillance.
Methods
CHB patients with well‐preserved liver function, who underwent ultrasonography and alpha‐foetoprotein (AFP) analysis every 6 months, were enrolled. Cox regression analysis was used to identify predictors for detection failure, defined as HCC initially diagnosed at Barcelona Clinic Liver Cancer (BCLC) stage B or C.
Results
Of the 4590 CHB patients (mean age, 52.1 years; men, 61.6%), 169 patients were diagnosed with HCC (3.68%) and 35 (20.7%) HCC patients were initially diagnosed with HCC BCLC stage B or C. The cumulative incidence of HCC detection failure was 0.2% at year 1 and 1.3% at year 5. Multivariate analyses indicated that cirrhosis (hazard ratio HR, 3.078; 95% CI, 1.389‐6.821; P = 0.006), AFP levels ≥9 ng/mL (HR, 5.235; 95% CI, 2.307‐11.957; P = 0.010), and diabetes mellitus (HR, 3.336; 95% CI, 1.341‐8.296; P = 0.010) were independent predictors of HCC detection failure. Another model that incorporated liver stiffness (LS) values identified LS values ≥11.7 kPa (HR, 11.045; 95% CI, 2.066‐59.037; P = 0.005) and AFP levels ≥9 ng/mL (HR, 4.802; 95% CI, 1.613‐14.297; P = 0.005) as predictors of detection failure.
Conclusions
In CHB patients undergoing regular surveillance with ultrasonography and alpha‐foetoprotein (AFP) analysis every 6 months, the HCC detection failure rate was not high (0.8% per person; 0.1% per test). However, careful attention should be paid in patients with advanced liver fibrosis (clinical cirrhosis or LS value >11.7 kPa), high AFP levels, or diabetes mellitus, who are prone to surveillance failure.
The Korea Invisible Mass Search (KIMS) collaboration has developed low-background NaI(Tl) crystals that are suitable for the direct detection of WIMP dark matter. Building on experience accumulated ...during the KIMS-CsI programs, the KIMS-NaI experiment will consist of a 200 kg NaI(Tl) crystal array surrounded by layers of shielding structures and will be operated at the Yangyang underground laboratory. The goal is to provide an unambiguous test of the DAMA/LIBRA annual modulation signature. Measurements of six prototype crystals show progress in the reduction of internal contamination from radioisotopes. Based on our understanding of these measurements, we expect to achieve a background level in the final detector configuration that is less than 1 count/day/keV/kg for recoil energies around 2 keV. The annual modulation sensitivity for the KIMS-NaI experiment shows that an unambiguous 7
σ
test of the DAMA/LIBRA signature would be possible with a 600 kg year exposure with this system.
Developments in quantum information science rely critically on entanglement-a fundamental aspect of quantum mechanics that causes parts of a composite system to show correlations stronger than can be ...explained classically. In particular, scalable quantum networks require the capability to create, store and distribute entanglement among distant matter nodes by means of photonic channels. Atomic ensembles can play the role of such nodes. So far, in the photon-counting regime, heralded entanglement between atomic ensembles has been successfully demonstrated through probabilistic protocols. But an inherent drawback of this approach is the compromise between the amount of entanglement and its preparation probability, leading to intrinsically low count rates for high entanglement. Here we report a protocol where entanglement between two atomic ensembles is created by coherent mapping of an entangled state of light. By splitting a single photon and performing subsequent state transfer, we separate the generation of entanglement and its storage. After a programmable delay, the stored entanglement is mapped back into photonic modes with overall efficiency of 17%. Together with improvements in single-photon sources, our protocol will allow 'on-demand' entanglement of atomic ensembles, a powerful resource for quantum information science.
Purpose
Incisional hernia is a complication following abdominal operation. Patients undergoing liver transplantation have a high risk of developing incisional hernia because of immunosuppression. The ...purpose of this study was to evaluate incisional hernia after liver transplantation and to identify risk factors for hernia formation in those patients.
Methods
We retrospectively reviewed 1044 adult patients with more than 2 years of follow-up in patients who underwent liver transplantation from January 2000 to December 2015.
Results
Incisional hernia was identified in 79 patients with more than 2 years of follow-up. The overall incisional hernia rate was 7.6%. The mean age and body mass index (BMI) of the patients with incisional hernia were 55 ± 9 years and 25.3 ± 3.7 kg/m
2
, respectively. No significant differences in gender, diagnosis, diabetes, Child–Pugh score, model for end-stage liver disease (MELD) score, donor type, hepatorenal syndrome, varix bleeding, ascites, hepatic encephalopathy, ventilator use, spontaneous bacterial peritonitis (SBP), or bile leakage were found between patients who did and did not develop incisional hernia. Patients with acute rejection before hernia development were more to have herniated patients hernia (
p
< 0.05).
Conclusion
Age greater than 55 years and high BMI were significant risk factors. We identified risk factors for the development of incisional hernia. Based on these risk factors, attention should be paid to incisional hernia in older and obese patients.
BACKGROUND AND PURPOSEThe detection of cerebral aneurysms on MRA is a challenging task. Recent studies have used deep learning-based software for automated detection of aneurysms on MRA and have ...reported high performance. The purpose of this study was to evaluate the incremental value of using deep learning-based software for the detection of aneurysms on MRA by 2 radiologists, a neurosurgeon, and a neurologist. MATERIALS AND METHODSTOF-MRA examinations of intracranial aneurysms were retrospectively extracted. Four physicians interpreted the MRA blindly. After a washout period, they interpreted MRA again using the software. Sensitivity and specificity per patient, sensitivity per lesion, and the number of false-positives per case were measured. Diagnostic performances, including subgroup analysis of lesions, were compared. Logistic regression with a generalized estimating equation was used. RESULTSA total of 332 patients were evaluated; 135 patients had positive findings with 169 lesions. With software assistance, patient-based sensitivity was statistically improved after the washout period (73.5% versus 86.5%, P < .001). The neurosurgeon and neurologist showed a significant increase in patient-based sensitivity with software assistance (74.8% versus 85.2%, P = .03, and 56.3% versus 84.4%, P < .001, respectively), while the number of false-positive cases did not increase significantly (23 versus 30, P = .20, and 22 versus 24, P = .75, respectively). CONCLUSIONSSoftware-aided reading showed significant incremental value in the sensitivity of clinicians in the detection of aneurysms on MRA without a significant increase in false-positive findings, especially for the neurosurgeon and neurologist. Software-aided reading showed equivocal value for the radiologist.
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