Abstract
High-pressure electrical resistivity measurements reveal that the mechanical deformation of ultra-hard WB
2
during compression induces superconductivity above 50 GPa with a maximum ...superconducting critical temperature,
T
c
of 17 K at 91 GPa. Upon further compression up to 187 GPa, the
T
c
gradually decreases. Theoretical calculations show that electron-phonon mediated superconductivity originates from the formation of metastable stacking faults and twin boundaries that exhibit a local structure resembling MgB
2
(hP3, space group 191, prototype AlB
2
). Synchrotron x-ray diffraction measurements up to 145 GPa show that the ambient pressure hP12 structure (space group 194, prototype WB
2
) continues to persist to this pressure, consistent with the formation of the planar defects above 50 GPa. The abrupt appearance of superconductivity under pressure does not coincide with a structural transition but instead with the formation and percolation of mechanically-induced stacking faults and twin boundaries. The results identify an alternate route for designing superconducting materials.
The recovery of the stratospheric ozone layer relies on the continued decline in the atmospheric concentrations of ozone-depleting gases such as chlorofluorocarbons
. The atmospheric concentration of ...trichlorofluoromethane (CFC-11), the second-most abundant chlorofluorocarbon, has declined substantially since the mid-1990s
. A recently reported slowdown in the decline of the atmospheric concentration of CFC-11 after 2012, however, suggests that global emissions have increased
. A concurrent increase in CFC-11 emissions from eastern Asia contributes to the global emission increase, but the location and magnitude of this regional source are unknown
. Here, using high-frequency atmospheric observations from Gosan, South Korea, and Hateruma, Japan, together with global monitoring data and atmospheric chemical transport model simulations, we investigate regional CFC-11 emissions from eastern Asia. We show that emissions from eastern mainland China are 7.0 ± 3.0 (±1 standard deviation) gigagrams per year higher in 2014-2017 than in 2008-2012, and that the increase in emissions arises primarily around the northeastern provinces of Shandong and Hebei. This increase accounts for a substantial fraction (at least 40 to 60 per cent) of the global rise in CFC-11 emissions. We find no evidence for a significant increase in CFC-11 emissions from any other eastern Asian countries or other regions of the world where there are available data for the detection of regional emissions. The attribution of any remaining fraction of the global CFC-11 emission rise to other regions is limited by the sparsity of long-term measurements of sufficient frequency near potentially emissive regions. Several considerations suggest that the increase in CFC-11 emissions from eastern mainland China is likely to be the result of new production and use, which is inconsistent with the Montreal Protocol agreement to phase out global chlorofluorocarbon production by 2010.
The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This ...Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9 GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36 GeV/c^{2}, rejecting cross sections above 9.2×10^{-48} cm at the 90% confidence level.
TMPRSS4 is a novel type II transmembrane serine protease found at the cell surface that is highly expressed in pancreatic, colon and gastric cancer tissues. However, the biological functions of ...TMPRSS4 in cancer are unknown. Here we show, using reverse transcription-PCR, that TMPRSS4 is highly elevated in lung cancer tissues compared with normal tissues and is also broadly expressed in a variety of human cancer cell lines. Knockdown of TMPRSS4 by small interfering RNA treatment in lung and colon cancer cell lines was associated with reduction of cell invasion and cell-matrix adhesion as well as modulation of cell proliferation. Conversely, the invasiveness, motility and adhesiveness of SW480 colon carcinoma cells were significantly enhanced by TMPRSS4 overexpression. Furthermore, overexpression of TMPRSS4 induced loss of E-cadherin-mediated cell-cell adhesion, concomitant with the induction of SIP1/ZEB2, an E-cadherin transcriptional repressor, and led to epithelial-mesenchymal transition events, including morphological changes, actin reorganization and upregulation of mesenchymal markers. TMPRSS4-overexpressing cells also displayed markedly increased metastasis to the liver in nude mice upon intrasplenic injection. Taken together, these studies suggest that TMPRSS4 controls the invasive and metastatic potential of human cancer cells by facilitating an epithelial-mesenchymal transition; TMPRSS4 may be a potential therapeutic target for cancer treatment.
The Reactor Experiment for Neutrino Oscillation (RENO) has been taking electron antineutrino (ν¯e) data from the reactors in Yonggwang, Korea, using two identical detectors since August 2011. Using ...roughly 500 live days of data through January 2013 we observe 290 775 (31 514) reactor ν¯e candidate events with 2.8% (4.9%) background in the near (far) detector. The observed visible positron spectra from the reactor ν¯e events in both detectors show a discrepancy around 5 MeV with regard to the prediction from the current reactor ν¯e model. Based on a far-to-near ratio measurement using the spectral and rate information, we have obtained sin22θ13=0.082±0.009(stat.)±0.006(syst.) and |Δmee2|=2.62−0.23+0.21(stat.)−0.13+0.12(syst.)×10−3 eV2.
We present a comprehensive analysis of electronic recoil vs nuclear recoil discrimination in liquid/gas xenon time projection chambers, using calibration data from the 2013 and 2014–2016 runs of the ...Large Underground Xenon experiment. We observe strong charge-to-light discrimination enhancement with increased event energy. For events with S1 = 120 detected photons, i.e., equivalent to a nuclear recoil energy of ∼100 keV, we observe an electronic recoil background acceptance of < 10−5 at a nuclear recoil signal acceptance of 50%. We also observe modest electric field dependence of the discrimination power, which peaks at a field of around 300 V/cm over the range of fields explored in this study (50 – 500 V/cm). In the weakly interacting massive particle search region of S1 = 1−80 phd , the minimum electronic recoil leakage we observe is (7.3 ± 0.6) × 10−4, which is obtained for a drift field of 240 – 290V/cm. Pulse shape discrimination is utilized to improve our results, and we find that, at low energies and low fields, there is an additional reduction in background leakage by a factor of up to 3. We develop an empirical model for recombination fluctuations which, when used alongside the Noble Element Scintillation Technique simulation package, correctly reproduces the skewness of the electronic recoil data. We use this updated simulation to study the width of the electronic recoil band, finding that its dominant contribution comes from electron-ion recombination fluctuations, followed in magnitude of contribution by fluctuations in the S1 signal, fluctuations in the S2 signal, and fluctuations in the total number of quanta produced for a given energy deposition.
Summary
Background
Significantly more patients with moderate‐to‐severe plaque psoriasis treated with the interleukin (IL)‐17A inhibitor ixekizumab vs. the IL‐23p19 inhibitor guselkumab in the IXORA‐R ...head‐to‐head trial achieved 100% improvement in Psoriasis Area and Severity Index (PASI 100) at week 12.
Objectives
To compare skin and nail clearance and patient‐reported outcomes for ixekizumab vs. guselkumab, up to week 24.
Methods
IXORA‐R enrolled adults with moderate‐to‐severe plaque psoriasis, defined as static Physician’s Global Assessment ≥ 3, PASI ≥ 12 and involved body surface area ≥ 10%. Statistical comparisons were performed using the Cochran–Mantel–Haenszel test stratified by pooled site. Time‐to‐first‐event comparisons were performed using Kaplan–Meier analysis, and P‐values were generated using adjusted log‐rank tests stratified by treatment group. Cumulative days at clinical and patient‐reported responses were compared by ancova. The trial was registered with ClinicalTrials.gov (NCT03573323).
Results
Of the 1027 patients randomly assigned, 90% completed the trial (465 of 520 ixekizumab and 459 of 507 guselkumab). As early as week 2 and through week 16, more patients on ixekizumab achieved PASI 100 (P < 0·01). At week 24, ixekizumab was noninferior to guselkumab (50% vs. 52%, difference −2·3%), with no statistically significant difference in PASI 100 (P = 0·41). More patients receiving ixekizumab showed completely clear nails at week 24 (52% vs. 31%, P = 0·007). The median time to first PASI 50/75/90 and PASI 100 were 2 and 7·5 weeks shorter, respectively, for patients on ixekizumab vs. guselkumab (P < 0·001). Patients on ixekizumab also had a greater cumulative benefit, with more days at PASI 90 and 100, with Dermatology Life Quality Index of 0 or 1, and itch free (P < 0·05). The frequency of serious adverse events was 3% for each group, with no new safety signals.
Conclusions
Ixekizumab was noninferior to guselkumab in complete skin clearance and superior in clearing nails at week 24. Ixekizumab cleared skin more rapidly in patients with moderate‐to‐severe plaque psoriasis, with a greater cumulative benefit, than guselkumab. Overall, the safety findings were consistent with the known safety profile for ixekizumab.
What is already known about this topic?
Patients with plaque psoriasis desire both high levels of clearance and rapid onset of treatment effects.
Ixekizumab is a high‐affinity monoclonal antibody that selectively targets interleukin (IL)‐17A.
In the 12‐week report of the IXORA‐R study, ixekizumab demonstrated significantly higher efficacy at early timepoints than the IL‐23p19 inhibitor guselkumab, with more patients achieving 100% improvement in Psoriasis Area and Severity Index (PASI 100) and improved quality of life as early as week 4.
What does this study add?
Patients on ixekizumab vs. guselkumab achieved similar levels of skin clearance and superior efficacy in the resolution of nail psoriasis at week 24.
Patients on ixekizumab vs. guselkumab had a greater cumulative benefit, with more days at PASI 90 and 100, more days when psoriasis did not impact their quality of life, and more itch‐free days.
The safety profiles of both drugs were consistent with those in previous studies.
Linked Comment: Puig. Br J Dermatol 2021; 184:992–993.
Galaxy clusters are the most massive virialized structures in the Universe and are formed through the gravitational accretion of matter over cosmic time
. The discovery
of an evolved galaxy cluster ...at redshift z = 2, corresponding to a look-back time of 10.4 billion years, provides an opportunity to study its properties. The galaxy cluster XLSSC 122 was originally detected as a faint, extended X-ray source in the XMM Large Scale Structure survey and was revealed to be coincident with a compact over-density of galaxies
with photometric redshifts of 1.9 ± 0.2. Subsequent observations
at millimetre wavelengths detected a Sunyaev-Zel'dovich decrement along the line of sight to XLSSC 122, thus confirming the existence of hot intracluster gas, while deep imaging spectroscopy from the European Space Agency's X-ray Multi-Mirror Mission (XMM-Newton) revealed
an extended, X-ray-bright gaseous atmosphere with a virial temperature of 60 million Kelvin, enriched with metals to the same extent as are local clusters. Here we report optical spectroscopic observations of XLSSC 122 and identify 37 member galaxies at a mean redshift of 1.98, corresponding to a look-back time of 10.4 billion years. We use photometry to determine a mean, dust-free stellar age of 2.98 billion years, indicating that star formation commenced in these galaxies at a mean redshift of 12, when the Universe was only 370 million years old. The full range of inferred formation redshifts, including the effects of dust, covers the interval from 7 to 13. These observations confirm that XLSSC 122 is a remarkably mature galaxy cluster with both evolved stellar populations in the member galaxies and a hot, metal-rich gas composing the intracluster medium.
We present the results from combining machine learning with the profile likelihood fit procedure, using data from the Large Underground Xenon (LUX) dark matter experiment. This approach demonstrates ...reduction in computation time by a factor of 30 when compared with the previous approach, without loss of performance on real data. We establish its flexibility to capture non-linear correlations between variables (such as smearing in light and charge signals due to position variation) by achieving equal performance using pulse areas with and without position-corrections applied. Its efficiency and scalability furthermore enables searching for dark matter using additional variables without significant computational burden. We demonstrate this by including a light signal pulse shape variable alongside more traditional inputs such as light and charge signal strengths. Furthermore, this technique can be exploited by future dark matter experiments to make use of additional information, reduce computational resources needed for signal searches and simulations, and make inclusion of physical nuisance parameters in fits tractable.
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