At ambient pressure, CrAs undergoes a first-order transition into a double-helical magnetic state atTN=265K, which is accompanied by a structural transition. The recent discovery of pressure-induced ...superconductivity in CrAs makes it important to clarify the nature of quantum phase transitions out of the coupled structural/helimagnetic order in this system. Here, we show, via neutron diffraction on the single-crystal CrAs under hydrostatic pressure (P), that the combined order is suppressed atPc≈10kbar, near which bulk superconductivity develops with a maximal transition temperatureTc≈2K. We further show that the coupled order is also completely suppressed by phosphorus doping inCrAs1−xPxat a criticalxc≈0.05, above which inelastic neutron scattering evidenced persistent antiferromagnetic correlations, providing a possible link between magnetism and superconductivity. In line with the presence of antiferromagnetic fluctuations nearPc(xc), theAcoefficient of the quadratic temperature dependence of resistivity exhibits a dramatic enhancement asP(x) approachesPc(xc), around whichρ(T)has a non-Fermi-liquid form. Accordingly, the electronic specific-heat coefficient ofCrAs1−xPxpeaks aroundxc. These properties provide clear evidence for quantum criticality, which we interpret as originating from a nearly second-order helimagnetic quantum phase transition that is concomitant with a first-order structural transition. Our findings in CrAs highlight the distinct characteristics of quantum criticality in bad metals, thereby bringing out new insights into the physics of unconventional superconductivity such as those occurring in the high-Tciron pnictides.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM, UPUK
With the rapidly growing attention to human-robot interfaces, soft robotics has attracted a great deal of interest. Soft robots have diverse advantages, including compliancy and safety, which ...contribute to seamless interactions with humans. To boost progress in the field, there is a need for compliant materials. Hydrogels are promising as compliant materials for soft robots because of their outstanding features, including high stretchability, transparency, ion conductivity, and biocompatibility. Furthermore, hydrogels provide innovative capabilities for soft robotics based on their unique responsiveness to stimuli. In this review, we discuss the unique features of hydrogel-based soft robots, from their fundamental working mechanisms to notable applications. Finally, we suggest perspectives on future directions that addressing potential challenges in the field of hydrogel soft robotics.
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•Unique features of hydrogel-based soft robots are reviewed from their fundamental working mechanisms to notable applications.•Covering all components of hydrogel-based soft robots including actuators, sensors, communicators, power sources, and computation circuits.•Suggesting perspectives on future directions for addressing potential challenges in the field of hydrogel soft robotics.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study was performed to compare the operation time, graft outcomes and complications between the endoscopic cartilage-perichondrium button technique and over-under technique for repairing large ...perforations.
A total of 52 chronic large perforations were randomly allocated to receive treatment using the endoscopic cartilage-perichondrium button technique (
= 26) or over-under technique (
= 26). The graft outcomes, mean operation time and post-operative complications were compared between the two groups at 12 months.
The study population consisted of 52 patients with unilateral chronic large perforations. All patients completed 12 months of follow up. The mean operation time was 32.3 ± 4.2 minutes in the button technique group and 51.6 ± 2.8 minutes in the over-underlay technique group (
< 0.01). The graft success rate at 12 months was 92.3 per cent (24 out of 26) in the button technique group and 96.2 per cent (25 out of 26) in the over-underlay group (
= 0.552).
The endoscopic cartilage-perichondrium button technique had similar graft success rates and hearing outcomes for large chronic perforations to the over-under technique, but significantly shortened the mean operation time.
MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) measurements taken during passes over Mercury's dayside hemisphere indicate that on four occasions the spacecraft remained in ...the magnetosheath even though it reached altitudes below 300 km. During these disappearing dayside magnetosphere (DDM) events, the spacecraft did not encounter the magnetopause until it was at very high magnetic latitudes, ~66 to 80°. These DDM events stand out with respect to their extremely high solar wind dynamic pressures, Psw ~140 to 290 nPa, and intense southward magnetic fields, Bz ~ −100 to −400 nT, measured in the magnetosheath. In addition, the bow shock was observed very close to the surface during these events with a subsolar altitude of ~1,200 km. It is suggested that DDM events, which are closely associated with coronal mass ejections, are due to solar wind compression and/or reconnection‐driven erosion of the dayside magnetosphere. The very low altitude of the bow shock during these events strongly suggests that the solar wind impacts much of Mercury's sunlit hemisphere during these events. More study of these disappearing dayside events is required, but it is likely that solar wind sputtering of neutrals from the surface into the exosphere maximizes during these intervals.
Key Points
The dayside magnetosphere of Mercury is observed to disappear at MESSENGER's orbit during some coronal mass ejection impacts
The cause appears to be extreme solar wind compression and/or reconnection‐driven erosion of Mercury's dayside magnetic field
The low altitude of the bow shock during these events strongly suggests that Mercury's dayside surface experiences direct solar wind impact
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In this study, we undertook a randomized phase III trial of 105 NSCLC patients with oligo (one to four) -brain metastases. Patients were randomly assigned (1:1) to receive either stereotactic ...radiosurgery (SRS) followed by chemotherapy or upfront chemotherapy alone. The results demonstrated that SRS followed by chemotherapy did not improve overall survival compared with upfront chemotherapy only.
It is unclear whether treating brain metastasis before starting systemic chemotherapy can improve survival compared with upfront chemotherapy in non-small-cell lung cancer (NSCLC) with asymptomatic cerebral oligo-metastases.
We undertook a randomized, controlled trial of 105 patients with one to four brain metastases, admitted to Samsung Medical Center between 2008 and 2013. Patients were randomly assigned to receive stereotactic radiosurgery (SRS) (49 patients) followed by chemotherapy or upfront chemotherapy (49 patients). The primary end point was overall survival (OS) and secondary end points included central nervous system (CNS) progression-free survival, progression to symptomatic brain metastasis and brain functional outcome.
The median age was 58 years (range, 29–85) with ECOG 0–1 performance status, and 40% of patients were never smokers. Most patients had adenocarcinoma, and about half of patients had only one brain metastasis, while the rest had multiple cerebral metastases. The median OS time was 14.6 months 95% confidence interval (CI), 9.2–20.0 in the SRS group and 15.3 months (95% CI, 7.2–23.4) for the upfront chemotherapy group (P = 0.418). There was no significant difference in time to CNS disease progression median, 9.4 months (SRS) versus 6.6 months (upfront chemotherapy),P = 0.248. Symptomatic progression of brain metastases was observed more frequently in the upfront chemotherapy group (26.5%) than the SRS group (18.4%) but without statistical significance.
Although this study included smaller sample size than initially anticipated due to early termination, SRS followed by chemotherapy did not improve OS in oligo-brain metastases NSCLC patients compared with upfront chemotherapy. Further study with large number of patients should be needed to confirm the use of upfront chemotherapy alone in this subgroup of patients.
NCT01301560.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The high-temperature stability and mechanical properties of refractory molybdenum alloys are highly desirable for a wide range of critical applications. However, a long-standing problem for these ...alloys is that they suffer from low ductility and limited formability. Here we report a nanostructuring strategy that achieves Mo alloys with yield strength over 800 MPa and tensile elongation as large as ~ 40% at room temperature. The processing route involves a molecular-level liquid-liquid mixing/doping technique that leads to an optimal microstructure of submicrometre grains with nanometric oxide particles uniformly distributed in the grain interior. Our approach can be readily adapted to large-scale industrial production of ductile Mo alloys that can be extensively processed and shaped at low temperatures. The architecture engineered into such multicomponent alloys offers a general pathway for manufacturing dispersion-strengthened materials with both high strength and ductility.
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IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The coexistence and competition between superconductivity and electronic orders, such as spin or charge density waves, have been a central issue in high transition-temperature (Tc) superconductors. ...Unlike other iron-based superconductors, FeSe exhibits nematic ordering without magnetism whose relationship with its superconductivity remains unclear. Moreover, a pressure-induced fourfold increase of Tc has been reported, which poses a profound mystery. Here we report high-pressure magnetotransport measurements in FeSe up to ∼15 GPa, which uncover the dome shape of magnetic phase superseding the nematic order. Above ∼6 GPa the sudden enhancement of superconductivity (Tc≤38.3 K) accompanies a suppression of magnetic order, demonstrating their competing nature with very similar energy scales. Above the magnetic dome, we find anomalous transport properties suggesting a possible pseudogap formation, whereas linear-in-temperature resistivity is observed in the normal states of the high-Tc phase above 6 GPa. The obtained phase diagram highlights unique features of FeSe among iron-based superconductors, but bears some resemblance to that of high-Tc cuprates.
Chromosomal rearrangements involving RET, which are found in about 1% of non-small cell lung cancer (NSCLC), define a unique molecular subset. We performed this study to examine the efficacy and ...safety of vandetanib 300 mg daily in this patient population.
This study was a multi-center, open-label, phase II clinical trial. Patients were enrolled if they had metastatic or recurrent NSCLC with a RET rearrangement, which was confirmed by fluorescence in situ hybridization, had progressive disease against platinum-based doublet chemotherapy, and had a performance status of 0–2. The primary endpoint was the objective response rate.
A total of 18 patients were enrolled in this study between July 2013 and October 2015. Patients were aged 35–71 years; three had a performance status of 2, and the majority were a heavily pretreated population (≥ two different previous chemotherapy regimens in 72% of the patients). Among the 17 evaluable patients, three had a partial response (objective response rate = 18%) and eight had a stable disease (disease control rate = 65%). Among these patients, the partial response or disease stabilization was durable for more than 6 months in eight patients. Vandetanib also showed a progression-free survival of 4.5 months, and an overall survival of 11.6 months during a median follow-up duration of 14 months. The safety profile was comparable with previous studies of vandetanib. Most vandetanib-related adverse events were mild with prevalent hypertension and rash (in >70% of patients). Grade 3 toxicity included hypertension (n = 3), QT prolongation (2), and elevation of aminotransferases (1), and as a consequence the dose was reduced in four patients. There were no adverse events associated with grade 4 or 5 toxicity.
Vandetanib is moderately active in pretreated patients with advanced NSCLC-harboring RET rearrangements.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract Background Programmed death-ligand 1 (PD-L1) expression has been suggested as a potential predictive biomarker of response to anti-PD-1/PD-L1 therapy. In this study, we investigated whether ...the expression of PD-L1 in tumour cells is affected by neoadjuvant concurrent chemoradiotherapy (CCRT) or chemotherapy in oesophageal squamous cell carcinoma. Patients and methods Between 2004 and 2014, we collected the medical records of locally advanced oesophageal cancer patients consecutively diagnosed and treated with neoadjuvant CCRT or chemotherapy, followed by curative resection. PD-L1 expression in acquired tissue specimens was evaluated by immunohistochemistry using the H-score. The changes in PD-L1 expression between paired samples were evaluated and we also analysed PD-L1 expression in surgical tumour specimens to evaluate its prognostic role. Results Twenty-eight paired tumour tissues that were acquired before and after neoadjuvant therapy were available: 19 patients with CCRT and 9 with chemotherapy before complete oesophagectomy. The PD-L1 H-score increased significantly from baseline tumour tissues to surgical tumour tissues after neoadjuvant CCRT ( P = 0.007, median H-score from 28 to 52), whereas it decreased significantly after neoadjuvant chemotherapy ( P = 0.048, median H-score from 53 to 22). In a total of 73 patients, including 45 additional cases for the prognosis analysis, patients with higher PD-L1 H-scores (≥20) had poorer overall survival (median 16.7 versus 32.9 months, P = 0.02) than those with lower H-scores (<20). Conclusions PD-L1 expression in tumour cells increased in oesophageal cancer patients who received neoadjuvant CCRT. Further studies with more cases are necessary to validate these findings.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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