High-energy cosmic-ray electrons and positrons (CREs), which lose energy quickly during their propagation, provide a probe of Galactic high-energy processes and may enable the observation of ...phenomena such as dark-matter particle annihilation or decay. The CRE spectrum has been measured directly up to approximately 2 teraelectronvolts in previous balloon- or space-borne experiments, and indirectly up to approximately 5 teraelectronvolts using ground-based Cherenkov γ-ray telescope arrays. Evidence for a spectral break in the teraelectronvolt energy range has been provided by indirect measurements, although the results were qualified by sizeable systematic uncertainties. Here we report a direct measurement of CREs in the energy range 25 gigaelectronvolts to 4.6 teraelectronvolts by the Dark Matter Particle Explorer (DAMPE) with unprecedentedly high energy resolution and low background. The largest part of the spectrum can be well fitted by a 'smoothly broken power-law' model rather than a single power-law model. The direct detection of a spectral break at about 0.9 teraelectronvolts confirms the evidence found by previous indirect measurements, clarifies the behaviour of the CRE spectrum at energies above 1 teraelectronvolt and sheds light on the physical origin of the sub-teraelectronvolt CREs.
Background
Autophagy is a lysosomal degradation pathway that is essential for cell survival, differentiation, and homeostasis. This study aimed to investigate the contribution of autophagy to the ...pathogenesis of CRS with nasal polyps (CRSwNP).
Methods
The expression of autophagic proteins microtubule‐associated protein 1 light chain 3B (LC3B)‐II, autophagy‐related proteins (Atg), and Beclin 1, substrate proteins (p62 and ubiquitinated proteins), and apoptotic signaling molecules cysteine‐aspartic protease‐3 and cysteine‐aspartic protease‐8, and poly‐ADP‐ribose polymerase in the sinonasal mucosa and nasal epithelial cells (NECs) was detected by immunohistochemistry and Western blotting. Autophagic vacuoles were observed with transmission electron microscopy. BEAS‐2B cells and NECs were treated with rapamycin, bafilomycin A1, or various cytokines. In some experiments, cultured NECs were transfected with small interfering RNA targeting p62 (sip62) or Atg5 (siAtg5). Cultured cells were analyzed with Western blotting and flow cytometry.
Results
Although autophagic protein expression and autophagic vacuole formation were increased in both eosinophilic and noneosinophilic CRSwNP, particularly in NECs, there was also an up‐regulation of substrate proteins and apoptotic signaling molecules. IFN‐γ, but not IL‐4, IL‐13, or IL‐17A, simultaneously enhanced LC3B‐II and p62 levels as well as cell apoptosis in BEAS‐2B cells and/or normal NECs. Bafilomycin A1 up‐regulated the levels of LC3B‐II and p62 in polyp NECs and IFN‐γ‐treated normal NECs. IFN‐γ‐induced apoptosis of normal NECs was exaggerated by bafilomycin A1 and siAtg5. Sip62 suppressed apoptosis of polyp NECs and IFN‐γ‐treated NECs. IFN‐γ protein levels were increased in both eosinophilic and noneosinophilic CRSwNP.
Conclusions
IFN‐γ induces activated but insufficient autophagy and thus contributes to a degree to p62‐dependent apoptosis of NECs in CRSwNP.
The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A ...hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.
The mechanism of superconductivity in cuprates remains one of the big challenges of condensed matter physics. High-Tc
cuprates crystallize into a layered perovskite structure featuring copper oxygen ...octahedral coordination. Due to the Jahn Teller effect in combination with the strong static Coulomb interaction, the octahedra in high-Tc
cuprates are elongated along the c axis, leading to a 3dx²-y² orbital at the top of the band structure wherein the doped holes reside. This scenario gives rise to 2D characteristics in high-Tc
cuprates that favor d-wave pairing symmetry. Here, we report superconductivity in a cuprate Ba₂CuO4-y, wherein the local octahedron is in a very exceptional compressed version. The Ba₂CuO4-y compound was synthesized at high pressure at high temperatures and shows bulk superconductivity with critical temperature (Tc
) above 70 K at ambient conditions. This superconducting transition temperature is more than 30 K higher than the Tc
for the isostructural counterparts based on classical La₂CuO₄. X-ray absorption measurements indicate the heavily doped nature of the Ba₂CuO4-y superconductor. In compressed octahedron, the 3d3z²-r² orbital will be lifted above the 3dx²-y² orbital, leading to significant 3D nature in addition to the conventional 3dx²-y² orbital. This work sheds important light on advancing our comprehensive understanding of the superconducting mechanism of high Tc
in cuprate materials.
The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This ...work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2
/
years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.
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 . . .
Development of efficient and durable oxygen evolution reaction (OER) catalysts has a direct impact on the water splitting efficiency and cost effectiveness. In this work, we report the successful ...synthesis of a new Ni(OH)
2
structure, strain-stabilized Ni(OH)
2
nanoribbons (NR-Ni(OH)
2
) two to three layers thick, with widths of 2-5 nm,
via
an electro-oxidation route. Conventional Ni(OH)
2
usually has negligible OER activity, while NR-Ni(OH)
2
shows high activity for the oxygen evolution reaction and an overpotential of 162 millivolts and furthermore exhibits long-term stability in alkaline electrolyte. The substantial reduction in the overpotential of NR-Ni(OH)
2
is due to its easier OOH* adsorption by the active four-coordinated Ni edge sites. The enhanced catalytic activity of NR-Ni(OH)
2
makes it an excellent candidate for industrial applications.
Development of efficient and durable oxygen evolution reaction (OER) catalysts has a direct impact on the water splitting efficiency and cost effectiveness.
Background
Acupuncture is used to treat chronic functional constipation (CFC) in China, despite limited evidence. We aim to assess the effectiveness and safety of acupuncture in managing CFC.
Methods
...A multicenter randomized controlled trial was performed involving 684 patients with CFC; the patients were randomly allocated to receive He acupuncture (n = 172), Shu‐mu acupuncture (n = 171), He‐shu‐mu acupuncture (n = 171), or oral administration of mosapride (n = 170). Sixteen sessions of acupuncture were given in the treatment duration of 4 weeks. The primary outcome was the change in spontaneous bowel movements (SBMs) at week 4 (at the end of treatment) compared to baseline. The secondary outcomes included stool consistency (Bristol scale), the degree of straining during defecation, and adverse events.
Key Results
The SBMs increased in all the four groups at week 4, and the magnitude of increase was equivalent in the four groups (He acupuncture, 2.7 95% CI, 2.3‐3.1; Shu‐mu acupuncture, 2.7 95% CI, 2.3‐3.0; He‐shu‐mu acupuncture, 2.2 95% CI, 1.9‐2.5; and mosapride, 2.4 95% CI, 2.0‐2.9; P = .226). However, the change in SBMs at week 8 was significantly smaller in mosapride group (1.4 95% CI, 1.0‐1.8) than the three acupuncture groups (2.4 95% CI, 2.1‐2.7, 2.3 95% CI, 1.9‐2.7, 2.1 95% CI, 1.7‐2.5 in He, Shu‐mu, and He‐shu‐mu group, respectively, P = .005).
Conclusions & Interferences
The three acupuncture treatments were as effective as mosapride in improving stool frequency and stool consistency in CFC, but the magnitude of the treatment effect is unknown due to the lack of sham acupuncture control.
The effectiveness of acupuncture in the treatment of chronic functional constipation is unknown. Our study result showed that acupuncture treatments are as effective as mosapride in improving stool frequency and stool consistency.
Three-dimensional (3D) topological Dirac semimetals (TDSs) represent an unusual state of quantum matter that can be viewed as "3D graphene." In contrast to 2D Dirac fermions in graphene or on the ...surface of 3D topological insulators, TDSs possess 3D Dirac fermions in the bulk. By investigating the electronic structure of Na3Bi with angle-resolved photoemission spectroscopy, we detected 3D Dirac fermions with linear dispersions along all momentum directions. Furthermore, we demonstrated the robustness of 3D Dirac fermions in Na3Bi against in situ surface doping. Our results establish Na3Bi as a model system for 3D TDSs, which can serve as an ideal platform for the systematic study of quantum phase transitions between rich topological quantum states.
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