Complex topological configurations are fertile ground for exploring emergent phenomena and exotic phases in condensed-matter physics. For example, the recent discovery of polarization vortices and ...their associated complex-phase coexistence and response under applied electric fields in superlattices of (PbTiO
)
/(SrTiO
)
suggests the presence of a complex, multi-dimensional system capable of interesting physical responses, such as chirality, negative capacitance and large piezo-electric responses
. Here, by varying epitaxial constraints, we discover room-temperature polar-skyrmion bubbles in a lead titanate layer confined by strontium titanate layers, which are imaged by atomic-resolution scanning transmission electron microscopy. Phase-field modelling and second-principles calculations reveal that the polar-skyrmion bubbles have a skyrmion number of +1, and resonant soft-X-ray diffraction experiments show circular dichroism, confirming chirality. Such nanometre-scale polar-skyrmion bubbles are the electric analogues of magnetic skyrmions, and could contribute to the advancement of ferroelectrics towards functionalities incorporating emergent chirality and electrically controllable negative capacitance.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Cracks in solid-state materials are typically irreversible. Here we report electrically reversible opening and closing of nanoscale cracks in an intermetallic thin film grown on a ferroelectric ...substrate driven by a small electric field (~0.83 kV/cm). Accordingly, a nonvolatile colossal electroresistance on-off ratio of more than 10
is measured across the cracks in the intermetallic film at room temperature. Cracks are easily formed with low-frequency voltage cycling and remain stable when the device is operated at high frequency, which offers intriguing potential for next-generation high-frequency memory applications. Moreover, endurance testing demonstrates that the opening and closing of such cracks can reach over 10
cycles under 10-μs pulses, without catastrophic failure of the film.
Abstract
We searched for shocked carbon chain chemistry (SCCC) sources with C
3
S abundances surpassing those of HC
5
N toward the dark cloud L1251, using the Effelsberg telescope at the
K
band ...(18–26 GHz). L1251-1 and L1251-3 are identified as the most promising SCCC sources. The two sources harbor young stellar objects. We conducted mapping observations toward L1251-A, the western tail of L1251, at
λ
∼ 3 mm with the Purple Mountain Observatory 13.7 m and the Nobeyama Radio Observatory 45 m telescopes in lines of C
2
H, N
2
H
+
, CS, HCO
+
, SO, HC
3
N, and C
18
O as well as in CO 3–2 using the James Clerk Maxwell Telescope (JCMT). The spectral data were combined with archival data including Spitzer and Herschel continuum maps for further analysis. Filamentary substructures labeled as F1–F6 were extracted in L1251, with F1 being associated with L1251-A hosting L1251-1. The peak positions of dense gas traced by HCO
+
are misaligned relative to those of the dust clumps. Episodic outflows are common in this region. The twisted morphology of F1 and velocity distribution along L1251-A may originate from stellar feedback. SCCC in L1251-1 may have been caused by outflow activities originated from the infrared source IRS1. The signposts of ongoing SCCC and the broadened line widths of C
3
S and C
4
H in L1251-1 as well as the distribution of HC
3
N are also related to outflow activities in this region. L1251-1 (IRS1) together with the previously identified SCCC source IRS3 demonstrate that L1251-A is an excellent region to study SCCC.
Dapsone is an important medication for the treatment of leprosy, but a life-threatening drug hypersensitivity syndrome develops in some patients. In this report from China, an
HLA-B
locus is ...identified as a strong genetic risk factor for the syndrome.
Dapsone (4-4′-sulfonyldianiline), which was first synthesized in 1908,
1
is both an antibiotic and an antiinflammatory agent. Dapsone alone or in combination with other drugs has been used for the prevention and treatment of infectious diseases (e.g., leprosy, malaria, and actinomycetoma, as well as
Pneumocystis jirovecii
pneumonia in persons with human immunodeficiency virus HIV infection) and chronic inflammatory diseases characterized by the infiltration of neutrophils or eosinophils (e.g., dermatitis herpetiformis, linear IgA dermatosis, subcorneal pustular dermatosis, and erythema elevatum diutinum).
2
,
3
About 0.5 to 3.6% of persons treated with dapsone have a drug hypersensitivity syndrome,
3
–
5
which was first described by . . .
Background
While the majority of studies report that a raised serum α‐fetoprotein (AFP) level before operation is associated with a high risk of recurrence and death in patients who undergo ...hepatectomy for hepatocellular carcinoma (HCC), results are conflicting. The aim of this study was to assess the prognostic value of AFP.
Methods
Serum AFP levels were measured in patients with hepatitis‐associated HCC who underwent hepatectomy between 1995 and 2012. Kaplan–Meier and multivariable analyses were performed to identify risk factors for overall and disease‐free survival. Univariable and multivariable Cox proportional hazards regression was used to evaluate the predictive value of AFP. Receiver operating characteristic (ROC) curves were generated to identify the AFP level that had the highest accuracy in discriminating between survivors and non‐survivors.
Results
Some 376 patients with hepatitis B virus (HBV)‐associated HCC were included in the study. The overall survival rate was 58·8 per cent in patients with an AFP level of 400 ng/ml or less compared with 40·4 per cent for those with a level exceeding 400 ng/ml (P = 0·001). AFP concentration above 400 ng/ml was an independent risk factor for shorter disease‐free and overall survival after surgery. ROC analysis indicated that the optimal cut‐off values for AFP varied for different subtypes of HCC. The sensitivity and specificity were lower with areas under the ROC curve of less than 0·600. An AFP level greater than 400 ng/ml was not sensitive enough to predict the prognosis in patients with an HCC diameter smaller than 3 cm.
Conclusion
A serum AFP level above 400 ng/ml predicts poor overall and recurrence‐free survival after hepatectomy in patients with HBV‐associated HCC. AFP is not a strong prognostic marker given its poor discriminatory power, with low sensitivity and specificity.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Histamine is a developmentally highly conserved autacoid found in most vertebrate tissues. Its physiological functions are mediated by four 7-transmembrane G protein-coupled receptors (H1R, H2R, H3R, ...H4R) that are all targets of pharmacological intervention. The receptors display molecular heterogeneity and constitutive activity. H1R antagonists are long known antiallergic and sedating drugs, whereas the H2R was identified in the 1970s and led to the development of H2R-antagonists that revolutionized stomach ulcer treatment. The crystal structure of ligand-bound H1R has rendered it possible to design new ligands with novel properties. The H3R is an autoreceptor and heteroreceptor providing negative feedback on histaminergic and inhibition on other neurons. A block of these actions promotes waking. The H4R occurs on immuncompetent cells and the development of anti-inflammatory drugs is anticipated.
Summary
Background
TCS (topical corticosteroids) are the first‐line drug in the treatment of oral lichen planus (OLP). However, the value of topical calcineurin inhibitors (TCI) including tacrolimus, ...pimecrolimus and ciclosporin for OLP is still controversial.
Objectives
To compare the efficacy and safety of TCI vs. TCS for OLP.
Methods
The authors searched PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science and four Chinese databases from 1950 to May 2018. The randomized controlled trials comparing TCI and TCS for OLP reported at least one of the following outcomes: improvement of clinical signs and/or symptoms, relapse, blood levels of TCI and adverse events.
Results
Twenty‐one trials involving 965 patients were included in the analysis. For the treatment of OLP (3–8 weeks), TCI including tacrolimus, pimecrolimus and ciclosporin were similar to TCS in efficacy. Tacrolimus–TCS resulted in similar outcomes, with relapse at 3 weeks to 6 months. Blood levels of TCI were usually undetectable. In addition, tacrolimus showed a statistically higher incidence of local adverse events than TCS for short‐term treatment. A few systemic adverse events occurred in the tacrolimus and ciclosporin groups, but they were not serious.
Conclusions
The evidence for tacrolimus (n = 12), pimecrolimus (n = 3) and ciclosporin (n = 6) demonstrated that treatment with TCI may be an alternative approach when OLP does not respond to the standard protocols. Tacrolimus 0·1% should be the first drug of choice when selecting TCI for short‐term treatment in recalcitrant OLP. Further well‐designed trials are warranted to evaluate the long‐term efficacy and safety of TCI.
What's already known about this topic?
The main topical drug for oral lichen planus (OLP) is topical corticosteroids (TCS).
Patients with OLP who are not responsive to TCS or are at risk of adverse events from TCS need other alternative drugs.
Topical calcineurin inhibitors (TCI), including tacrolimus, pimecrolimus and ciclosporin, have become a hot topic in a variety of mucocutaneous immune‐mediated diseases.
What does this study add?
TCI including tacrolimus, pimecrolimus and ciclosporin were similar to TCS in efficacy for the short‐term treatment of OLP.
The local adverse events of tacrolimus were higher than with TCS. A few systemic adverse events were reported with TCI, but they were all tolerable and not serious.
The limited evidence for pimecrolimus (three trials) and ciclosporin (six trials) requires further studies to evaluate the short‐term and long‐term efficacy and safety of TCI compared with TCS.
Linked Comment: Thongprasom. Br J Dermatol 2019; 181:1120.
Plain language summary available online
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Land-surface albedo plays a critical role in the earth's radiant energy budget studies. Satellite remote sensing provides an effective approach to acquire regional and global albedo observations. ...Owing to cloud coverage, seasonal snow and sensor malfunctions, spatiotemporally continuous albedo datasets are often inaccessible. The Global LAnd Surface Satellite (GLASS) project aims at providing a suite of key land surface parameter datasets with high temporal resolution and high accuracy for a global change study. The GLASS preliminary albedo datasets are global daily land-surface albedo generated by an angular bin algorithm (Qu et al., 2013). Like other products, the GLASS preliminary albedo datasets are affected by large areas of missing data; beside, sharp fluctuations exist in the time series of the GLASS preliminary albedo due to data noise and algorithm uncertainties. Based on the Bayesian theory, a statistics-based temporal filter (STF) algorithm is proposed in this paper to fill data gaps, smooth albedo time series, and generate the GLASS final albedo product. The results of the STF algorithm are smooth and gapless albedo time series, with uncertainty estimations. The performance of the STF method was tested on one tile (H25V05) and three ground stations. Results show that the STF method has greatly improved the integrity and smoothness of the GLASS final albedo product. Seasonal trends in albedo are well depicted by the GLASS final albedo product. Compared with MODerate resolution Imaging Spectroradiometer (MODIS) product, the GLASS final albedo product has a higher temporal resolution and more competence in capturing the surface albedo variations. It is recommended that the quality flag should be always checked before using the GLASS final albedo product.
We report a giant, ∼22%, electroresistance modulation for a metallic alloy above room temperature. It is achieved by a small electric field of 2 kV/cm via piezoelectric strain-mediated ...magnetoelectric coupling and the resulting magnetic phase transition in epitaxial FeRh/BaTiO_{3} heterostructures. This work presents detailed experimental evidence for an isothermal magnetic phase transition driven by tetragonality modulation in FeRh thin films, which is in contrast to the large volume expansion in the conventional temperature-driven magnetic phase transition in FeRh. Moreover, all the experimental results in this work illustrate FeRh as a mixed-phase model system well similar to phase-separated colossal magnetoresistance systems with phase instability therein.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Abstract
We report on analysis of observations of the bright transient X-ray pulsar Swift J0243.6+6124 obtained during its 2017-2018 giant outburst with Insight-HXMT, NuSTAR, and Swift observatories. ...We focus on the discovery of a sharp state transition of the timing and spectral properties of the source at super-Eddington accretion rates, which we associate with the transition of the accretion disk to a radiation pressure dominated (RPD) state, the first ever directly observed for magnetized neutron star. This transition occurs at slightly higher luminosity compared to already reported transition of the source from sub- to super-critical accretion regime associate with onset of an accretion column. We argue that this scenario can only be realized for comparatively weakly magnetized neutron star, not dissimilar to other ultra-luminous X-ray pulsars (ULPs), which accrete at similar rates. Further evidence for this conclusion is provided by the non-detection of the transition to the propeller state in quiescence which strongly implies compact magnetosphere and thus rules out magnetar-like fields.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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