One favorable situation for spins to enter the long-sought quantum spin liquid (QSL) state is when they sit on a kagome lattice. No consensus has been reached in theory regarding the true ground ...state of this promising platform. The experimental efforts, relying mostly on one archetypal material ZnCu_{3}(OH)_{6}Cl_{2}, have also led to diverse possibilities. Apart from subtle interactions in the Hamiltonian, there is the additional degree of complexity associated with disorder in the real material ZnCu_{3}(OH)_{6}Cl_{2} that haunts most experimental probes. Here we resort to heat transport measurement, a cleaner probe in which instead of contributing directly, the disorder only impacts the signal from the kagome spins. For ZnCu_{3}(OH)_{6}Cl_{2}, we observed no contribution by any spin excitation nor obvious field-induced change to the thermal conductivity. These results impose strong constraints on various scenarios about the ground state of this kagome compound: while certain quantum paramagnetic states other than a QSL may serve as natural candidates, a QSL state, gapless or gapped, must be dramatically modified by the disorder so that the kagome spin excitations are localized.
Abstract
We present a pluggable radiation-tolerant 4-level Pulse-Amplitude-Modulation (PAM4) optical transmitter module called GBT20 (Giga-Bit Transmitter at 20 Gbps) for particle-physics ...experiments. GBT20 has an OSFP or firefly connector to input 16 bit data each at 1.28 Gbps. The GBT20 drives a VCSEL die with an LC lens or a VCSEL TOSA and interfaces an optical fiber with a standard LC connector. The minimum module, including the host connector, occupies 41 mm × 13 mm × 6 mm. At 20.48 Gbps, the minimum Transmitter Dispersion Eye Closure Quaternary (TDECQ) is around 0.7 dB. The power consumption is around 164 mW in the low-power mode. The SEE cross-section is below 7.5 × 10
−14
cm
2
. No significant performance degrades after a TID of 5.4 kGy.
•The time-dependent behavior of the Beishan granite at different T and stress level is studied.•Strength degradation is noticed at a constant loading stress lower than the crack damage stress.•Rock ...samples are found to fail at a similar axial strain at a given confinement in creep tests.•The temperature (<90°C) and stress effect on the critical state to failure is found to be limited.•The AE event is found to more sensitive to the occurrence of rock failure than the deformation.
The delicate self-intertwined domain structures inside the grains of the polycrystalline CaCu3Ti4O12 (CCTO) were discovered by scanning electron microscopy (SEM) and high-resolution transmission ...electron microscopy (HRTEM), which provided a direct clue in understanding the mystery of the huge dielectric response of this intriguing material. Domain morphologies with and without terrace and ledge were observed by SEM. The detailed domain structures were further examined by HRTEM, and it was found that they contained strained and unstrained domains. The strained domains essentially are constructed by various dimensional superlattices. The coherent domain boundaries were considered to be strained, composition-disordered, and insulating. A microstructural model and its equivalent circuit based on a series connection with semiconducting domain interior, insulating domain boundary, and insulating grain boundary have been established, which not only solve the contradictory explanation of the dielectric response between polycrystalline and single-crystal CCTO but also provide a reasonable interpretation of the experimental results related to enhancement of the dielectric responses of CCTO.
We survey contemporary studies of hadrons and strongly interacting quarks using QCD's Dyson-Schwinger equations, addressing the following aspects: confinement and dynamical chiral symmetry breaking; ...the hadron spectrum; hadron elastic and transition form factors, from small- to large-Q super(2); parton distribution functions; the physics of hadrons containing one or more heavy quarks; and properties of the quark gluon plasma.
AbstractCrackNet is the result of an 18-month collaboration within a 10-person team to develop a deep learning–based pavement crack detection software that demonstrated successes in terms of ...consistency for both precision and bias. This paper proposes an improved architecture of CrackNet called CrackNet II for enhanced learning capability and faster performance. The proposed CrackNet II represents two major modifications on the original CrackNet. First, the feature generator, which provides handcrafted features through fixed and nonlearnable procedures, is no longer used in CrackNet II. Consequently, all layers in CrackNet II have learnable parameters that are tuned during the learning process. Second, CrackNet II has a deeper architecture with more hidden layers but fewer parameters. Such an architecture yields five times faster performance compared with the original CrackNet. Similar to the original CrackNet, CrackNet II still uses invariant image width and height through all layers to place explicit requirements on pixel-perfect accuracy. In addition, the combination of a convolution layer and a 1×1 convolution layer was repeated in CrackNet II to learn local motifs with different sizes of local receptive fields. CrackNet II was trained with 2,500 diverse example images and then demonstrated to outperform the original CrackNet. The experiment using 200 testing images showed that CrackNet II performs generally better than the original CrackNet in terms of both precision and recall. The overall precision, recall, and F-measure achieved by CrackNet II for the 200 testing images were 90.20, 89.06, and 89.62%, respectively. Compared with the original CrackNet, CrackNet II is capable of detecting more fine or hairline cracks, while eliminating more local noises and maintaining much faster processing speed.
The OPTIMAL study found that erlotinib improved progression-free survival (PFS) versus standard chemotherapy in Chinese patients with advanced EGFR mutation-positive non-small-cell lung cancer ...(NSCLC). This report describes the quality of life (QoL) and updated PFS analyses from this study.
Chinese patients ≥18 years with histologically confirmed stage IIIB or IV NSCLC and a confirmed activating mutation of EGFR (exon 19 deletion or exon 21 L858R point mutation) received erlotinib (150 mg/day; n = 82) or gemcitabine–carboplatin (n = 72). The primary efficacy end point was PFS; QoL was assessed using the Functional Assessment of Cancer Therapy-Lung (FACT-L) questionnaire, Trial Outcome Index (TOI) and Lung Cancer Subscale (LCS).
Patients receiving erlotinib experienced clinically relevant improvements in QoL compared with the chemotherapy group in total FACT-L, TOI and LCS (P < 0.0001 for all scales). Erlotinib scored better than chemotherapy for all FACT-L subscales from baseline to cycles 2 and 4 (non-significant). In the updated analysis, PFS was significantly longer for erlotinib than chemotherapy (median PFS 13.7 versus 4.6 months; HR = 0.164, 95% CI = 0.105–0.256; P < 0.0001), which was similar to the previously reported primary analysis.
Erlotinib improves QoL compared with standard chemotherapy in the first-line treatment of patients with EGFR mutation-positive advanced NSCLC.
To better understand the photodegradation of polycyclic aromatic hydrocarbons (PAH) in solid phase in natural environment, laboratory experiments were conducted to study the influencing factors, ...kinetics and intermediate compound of pyrene photodegradation by iron oxides. The results showed that the pyrene photodegradation rate followed the order of α-FeOOH
>
α-Fe
2O
3
>
γ-Fe
2O
3
>
γ-FeOOH at the same reaction conditions. Lower dosage of α-FeOOH and higher light intensity increased the photodegradation rate of pyrene. Iron oxides and oxalic acid can set up a photo-Fenton-like system without additional H
2O
2 in solid phase to enhance the photodegradation of pyrene under UV irradiation. All reaction followed the first-order reaction kinetics. The half-life (
t
1/2) of pyrene in the system showed the higher efficiencies of using iron oxide as photocatalyst to degrade pyrene. Intermediate compound pyreno was found during photodegradation reactions by gas chromatography–mass spectrometry (GC–MS). The photodegradation efficiency for PAHs in this photo-Fenton-like system was also confirmed by using the contaminated soil samples. This work provides some useful information to understand the remediation of PAHs contaminated soils by photochemical techniques under practical condition.
Background
The overproduction of IgE plays a critical role in the pathogenesis of allergy; the mechanism is unclear. Histone‐acetyltransferase (HAT) activities are required in gene transcription of a ...large number of molecules in the immune system of the body.
Objectives
This study tests a hypothesis that HAT Tat‐interactive protein 60 (Tip60) plays an important role in the initiation of IgE‐mediated allergy.
Methods
The effects of Tip60 on regulating IgE expression were assessed with B cells. An intestinal allergy mouse model was developed to assess the role of Tip60 in the induction of IgE‐mediated allergic inflammation.
Results
High levels of Tip60 were observed in the peripheral B cells of patients with FA. Tat‐interactive protein 60 (Tip60) was required in the expression of IgE and IgG1 in B cells by inducing the chromatin remolding at the gene locus, in which histone acetylation, signal transducer and activator of transcription 6 (STAT6), and nuclear factor‐κB at the locus of Iε promoter were markedly increased. Blocking Tip60 significantly attenuated the allergic inflammation in the mouse intestinal mucosa.
Conclusions
Tat‐interactive protein 60 (Tip60) plays an important role in the induction of IgE in B cells. Blocking Tip60 inhibits the allergic inflammation in the intestine, suggesting Tip60 inhibitor may be a potential anti‐allergy drug.
Summary
Dysfunction of the immune regulatory system plays an important role in the pathogenesis of rheumatoid arthritis (RA). Vasoactive intestinal peptide (VIP) has multiple bioactivities. This ...study aims to investigate the role of VIP in the maintenance of the immune regulatory capacity of monocytes (Mos). Human peripheral blood samples were collected from RA patients and healthy control (HC) subjects. Mos and CD14+ CD71–CD73+CD25+ regulatory Mos (RegMos) were isolated from the blood samples and characterized by flow cytometry. A rat RA model was developed to test the role of VIP in the maintenance of the immune regulatory function of Mos. The results showed that RegMos of HC subjects had immune suppressive functions. RegMos of RA patients expressed less interleukin (IL)‐10 and showed an incompetent immune regulatory capacity. Serum levels of VIP were lower in RA patients, which were positively correlated with the expression of IL‐10 in RegMos. In‐vitro experiments showed that the IL‐10 mRNA decayed spontaneously in RegMos, which could be prevented by the presence of VIP in the culture. VIP suppressed the effects of tristetraprolin (TTP) on inducing IL‐10 mRNA decay in RegMos. Administration of VIP inhibited experimental RA in rats through restoring the IL‐10 expression in RegMos. RegMos have immune suppressive functions. VIP is required in maintaining IL‐10 expression in RegMos. The data suggest that VIP has translational potential in the treatment of immune disorders such as RA.
A fraction of peripheral monocyte has immune regulatory function, which is impaired in patients with rheumatoid arthritis.
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