Real-imaginary spectrum decomposition of the transparency spectra in microwave dressed Rydberg systems.

To distinguish the contributions of electromagnetically induced transparency (EIT) and Autler-Townes splitting (ATS) in their applications in precision laser spectroscopy, we propose a real-imaginary spectrum decomposition method to investigate the transparency spectra in a four-level microwave (MW) dressed Rydberg system. We show that the opening transparency windows in the absorption spectra of probe field is a prominent character by EIT, EIT-ATS crossover, and ATS when the MW field is turned off and the intensity of the control field is adjusted. When the MW field is turned on and gradually increased, the EIT is destroyed and disappears. In addition, the most prominent characters that open a transparency window are the EIT-ATS crossover and the ATS. Then, if we further increase the intensity of the MW field, we find that the transparency windows open mainly due to the ATS. Compared to the previous considerations of this issue, which were limited to three-level systems, our four-level scheme reported here is useful for understanding the features of quantum interference in multilevel atomic systems, and has potential applications to study enhanced sensitivity, measurement spectroscopic, quantum processing, quantum communication, and transmission.

Spalling Criterion of Hard Brittle Rock Mass Based on Dilatation Lateral Strain.

Spalling failure is a typical failure phenomenon after excavation and unloading of a deep, hard brittle rock mass, which seriously threatens the safe construction of deep roadways (tunnels) and other projects. From the engineering viewpoint, it is essential to accurately evaluate the range and depth of surrounding rock spalling failure. From the perspective of the laboratory and engineering site, the strength and formation mechanism of hard rock spalling failure were statistically summarized and analyzed. Under uniaxial and low confining pressure conditions, when the load reached the rock damage stress, cracks in the rock penetrated to form a failure plane approximately parallel to the axial loading direction, and the strength of rock mass spalling was much smaller than that of intact rock spalling. A triaxial compression test was conducted to analyze the dilatation axial strain and dilatation lateral strain characteristics of gneiss. The results showed that dilatation axial strain gradually increased with the increase of confining pressure, whereas dilatation lateral strain was almost unchanged. Therefore, a safety factor (FS) based on dilatation lateral strain was developed. Through comparison with other strain-based spalling criteria, the establishment and physical meaning of the method were described in detail. In addition, FS was applied to analyze the deep roadway of the Hongtoushan Copper Mine in China and the Rm415 test tunnel in Canada. The results showed that the spalling criterion could accurately indicate the range and depth of the surrounding rock spalling failure, which verified the rationality and applicability of the new spalling criterion. Thus, FS can be utilized as a new theory and analysis tool for the assessment and prevention of spalling failure in deep hard rock roadways.

Bright solitons in a spin-orbit-coupled dipolar Bose-Einstein condensate trapped within a double-lattice.

By effectively controlling the dipole-dipole interaction, we investigate the characteristics of the ground state of bright solitons in a spin-orbit coupled dipolar Bose-Einstein condensate. The dipolar atoms are trapped within a double-lattice which consists of a linear and a nonlinear lattice. We derive the motion equations of the different spin components, taking the controlling mechanisms of the dipole-dipole interaction into account. An analytical expression of dipole-dipole interaction is derived. By adjusting the dipole polarization angle, the dipole interaction can be adjusted from attraction to repulsion. On this basis, we study the generation and manipulation of the bright solitons using both the analytical variational method and numerical imaginary time evolution. The stability of the bright solitons is also analyzed and we map out the stability phase diagram. By adjusting the long-range dipole-dipole interaction, one can achieve manipulation of bright solitons in all aspects, including the existence, width, nodes, and stability. Considering the complexity of our system, our results will have enormous potential applications in quantum simulation of complex systems.

Design and analysis of a new type of mobile ice cooling equipment for deep mine.

In the background environment of the serious problem of high temperature heat damage in deep mining, some mines have complex and interlocking forms of roadway arrangement, with the innovative concept of cooling on demand as the principle, this paper develops a mobile ice cooling equipment, and introduces and explains the equipment from the perspective of principle, composition and dimensions. and uses Comsol simulation software to simulate and analyze the main heat exchange process of the mobile ice cooling equipment under the conditions of two cooling sources, obtains quantitative results on the finned tube arrangement parameters and the heat exchange cooling effect of the equipment under ideal conditions, which provides data for the optimization and upgrading of this mobile ice cooling equipment. The results show that the mobile cooling equipment is capable of feeding the desired temperature of the cooling air into deep mine, and with flexible, convenient, efficient, and cost effective. This research and development is a new exploration of deep ventilation and cooling technology and equipment means, puts forward a new concept, accumulates valuable experience, and lays the foundation for the subsequent related research and optimization.

Optimal optical Ferris wheel solitons in a nonlocal Rydberg medium.

We propose a scheme for the creation of stable optical Ferris wheel (OFW) solitons in a nonlocal Rydberg electromagnetically induced transparency (EIT) medium. Depending on a careful optimization of both the atomic density and the one-photon detuning, we obtain an appropriate nonlocal potential provided by the strong interatomic interaction in Rydberg states that can perfectly compensate for the diffraction of the probe OFW field. Numerical results show that the fidelity remains larger than 0.96, while the propagation distance has exceeded 160 diffraction lengths. Higher-order OFW solitons with arbitrary winding numbers are also discussed. Our study provides a straightforward route to generate spatial optical solitons in the nonlocal response region of cold Rydberg gases.

Soliton molecules and their scattering by a localized P T-symmetric potential in atomic gases.

We propose a physical scheme to study the formation of optical soliton molecules (SMs), consisting of two solitons bound together with a π-phase difference, and the scattering of SMs by a localized parity-time (P T)-symmetric potential. In order to stabilize SMs, we apply an additional space-dependent magnetic field to introduce a harmonic trapping potential for the two solitons and balance the repulse interaction induced by the π-phase difference between them. On the other hand, a localized complex optical potential obeying P T symmetry can be created through an incoherent pumping and spatial modulation of the control laser field. We investigate the scattering of optical SMs by the localized P T-symmetric potential, which exhibits evident asymmetric behavior and can be actively controlled by changing the incident velocity of SMs. Moreover, the P T symmetry of the localized potential, together with the interaction between two solitons of the SM, can also have a significant effect on the SM scattering behavior. The results presented here may be useful for understanding the unique properties of SMs and have potential applications in optical information processing and transmission.

SAF-248, a novel PI3Kδ-selective inhibitor, potently suppresses the growth of diffuse large B-cell lymphoma.

PI3Kδ is expressed predominately in leukocytes and overexpressed in B-cell-related malignances. PI3Kδ has been validated as a promising target for cancer therapy, and specific PI3Kδ inhibitors were approved for clinical practice. However, the substantial toxicity and relatively low efficacy as a monotherapy in diffuse large B-cell lymphoma (DLBCL) limit their clinical use. In this study, we described a novel PI3Kδ inhibitor SAF-248, which exhibited high selectivity for PI3Kδ (IC50 = 30.6 nM) over other PI3K isoforms at both molecular and cellular levels, while sparing most of the other human protein kinases in the kinome profiling. SAF-248 exhibited superior antiproliferative activity against 27 human lymphoma and leukemia cell lines compared with the approved PI3Kδ inhibitor idelalisib. In particular, SAF-248 potently inhibited the proliferation of a panel of seven DLBCL cell lines (with GI50 values < 1 µM in 5 DLBCL cell lines). We demonstrated that SAF-248 concentration-dependently blocked PI3K signaling followed by inducing G1 phase arrest and apoptosis in DLBCL KARPAS-422, Pfeiffer and TMD8 cells. Its activity against the DLBCL cells was negatively correlated to the protein level of PI3Kα. Oral administration of SAF-248 dose-dependently inhibited the growth of xenografts derived from Pfeiffer and TMD8 cells. Activation of mTORC1, MYC and JAK/STAT signaling was observed upon prolonged treatment and co-targeting these pathways would potentiate the activity of SAF-248. Taken together, SAF-248 is a promising selective PI3Kδ inhibitor for the treatment of DLBCL and rational drug combination would further improve its efficacy.

Band evolution and Landau-Zener Bloch oscillations in strained photonic rhombic lattices.

We investigate band evolution of chiral and non-chiral symmetric flatband photonic rhombic lattices by applying a strain along the diagonal direction, and thereby demonstrating Landau-Zener Bloch (LZB) oscillations in the presence of a refractive index gradient. The chiral and non-chiral symmetric rhombic lattices are obtained by adding a detuning to uniform lattices. For the chiral symmetric lattices, the middle flatband is perturbed due to the chiral symmetry breaking while a nearly flatband appears as the bottom band with the increase of strain-induced next-nearest-neighbor hopping. Consequently, LZB oscillations exhibit intriguing characteristics such as asymmetric energy transitions and almost complete suppression of the oscillations. Nevertheless, for the non-chiral symmetric lattices, flatband persists owing to the retained particle-hole symmetry and evolves into the bottom band. Remarkably, the band gap can be readily tuned, which allows controlling of the amplitude of Landau-Zener tunneling (LZT) rate and may lead to thorough LZT. Our analysis provides an alternative perspective on the generation of tunable flatband and may also bring insight to study the symmetry and topological characterization of the flatband.

SAF-189s, a potent new-generation ROS1 inhibitor, is active against crizotinib-resistant ROS1 mutant-driven tumors.

The ROS1 fusion kinase is an attractive antitumor target. Though with significant clinical efficacy, the well-known first-generation ROS1 inhibitor (ROS1i) crizotinib inevitably developed acquired resistance due to secondary point mutations in the ROS1 kinase. Novel ROS1is effective against mutations conferring secondary crizotinib resistance, especially G2032R, are urgently needed. In the present study, we evaluated the antitumor efficacy of SAF-189s, the new-generation ROS1/ALK inhibitor, against ROS1 fusion wild-type and crizotinib-resistant mutants. We showed that SAF-189s potently inhibited ROS1 kinase and its known acquired clinically resistant mutants, including the highly resistant G2032R mutant. SAF-189s displayed subnanomolar to nanomolar IC50 values against ROS1 wild-type and mutant kinase activity and a selectivity vs. other 288 protein kinases tested. SAF-189s blocked cellular ROS1 signaling, and in turn potently inhibited the cell proliferation in HCC78 cells and BaF3 cells expressing ROS1 fusion wild-type and resistance mutants. In nude mice bearing BaF3/CD74-ROS1 or BaF3/CD74-ROS1G2032R xenografts, oral administration of SAF-189s dose dependently suppressed the growth of both ROS1 wild-type- and G2032R mutant-driven tumors. In a patient-derived xenograft model of SDC4-ROS1 fusion NSCLC, oral administration of SAF-189s (20 mg/kg every day) induced tumor regression and exhibited notable prolonged and durable efficacy. In addition, SAF-189s was more potent than crizotinib and comparable to lorlatinib, the most advanced ROS1i known against the ROS1G2032R. Collectively, these results suggest the promising potential of SAF-189s for the treatment of patients with the ROS1 fusion G2032R mutation who relapse on crizotinib. It is now recruiting both crizotinib-relapsed and naive ROS1-positive NSCLC patients in a multicenter phase II trial (ClinicalTrials.gov Identifier: NCT04237805).

Robust Majorana edge modes with low frequency multiple time periodic driving.

Floquet Majorana edge modes capture the topological features of periodically driven p-wave superconductors. We present a Kitaev chain with multiple time periodic driving terms. Our results demonstrate how multiple driving will affect Floquet bands in frequency space, leading to more robust Floquet Majorana edge modes against driving frequency ω in comparison with the single driving scenario. Meanwhile, we have proposed how to predict Majorana edge modes via the Zak phase of Floquet bands. Besides, in contrast to the cases with single driving term, where the constant phase can be gauged out by properly choosing the initial time, we have shown the relative phase between multiple driving can not be gauged out and will play a dominant role in deciding topological phase transitions. For the sake of completeness, we also investigate the high frequency limit. Analytical results on effective Hamiltonian can be obtained via Magnus expansion and relative phase induced topological transitions can be shown explicitly.

Adiabatic and high-fidelity quantum gates with hybrid Rydberg-Rydberg interactions.

Rydberg blockaded gate is a fundamental ingredient for scalable quantum computation with neutral Rydberg atoms. However the fidelity of such a gate is intrinsically limited by a blockade error coming from a Rydberg level shift that forbids its extensive use. Based on a dark-state adiabatic passage, we develop a novel protocol for realizing a two-atom blockade-error-free quantum gate in a hybrid system with simultaneous van der Waals (vdWsI) and resonant dipole-dipole interactions (DDI). The basic idea relies on converting the roles of two interactions, which is, the DDI serves as one time-dependent tunable pulse and the vdWsI acts as a negligible middle level shift, as long as the adiabatic condition is preserved. We adopt an optimized super-Gaussian optical pulse with kπ(k ≫ 1) area accompanied by a smooth tuning for the DDI, composing a circular stimulated Raman adiabatic passage, which can robustly ensure a faster operation time ∼ 80ns as well as a highly-efficient gate fidelity ∼ 0.9996. This theoretical protocol offers a flexible treatment for hybrid interactions in complex Rydberg systems, enabling on-demand design of new types of effective Rydberg quantum gate devices.

A PRISMA-compliant systematic review and meta-analysis of the relationship between thyroid disease and different levels of iodine intake in mainland China.

BACKGROUND: Low-iodine intake has historically been an issue in China, causing widespread iodine deficiency diseases (IDD). China started to introduce universal salt iodization in 1995, but reports of increased thyroid disease are a concern and appropriate levels of iodine intake must be considered. OBJECTIVE: To assess the prevalence of thyroid disease with different urinary iodine concentrations (UICs) in the general population of those residing in mainland China. Furthermore, we aimed to analyze the relationship between thyroid disease and UIC, to provide guidance in establishing effective health policies regarding iodine intake. METHODS: PubMed, Cochrane, Embase, CNKI, Wan fang, and CQVIP databases were searched for random community-based relevant studies with UIC published before January 2016 in mainland China. Two independent reviewers extracted data from eligible citations, and obtained prevalence of thyroid disease for different UICs, as well as the intergroup interaction P values. RESULTS: Forty-three articles were included. The prevalence of thyroid nodules was 22.3% (95% confidence interval [CI]: 20.6%-24.1%) for the low-iodine group, 25.4% (95% CI: 20.8%-28.8%) for the medium-iodine group, and 6.8% (95% CI: 2.8%-11.5%) for the high-iodine group. In the high-iodine group, the prevalence of thyroid nodules was lower than the other groups. The prevalence of 8.3% (95% CI: 3.8%-17.3%) for subclinical hypothyroidism in the high-iodine group was significantly higher than the low- and medium-iodine groups (P < .01). The prevalence of hypothyroidism in the medium-iodine group was 0.2% (95% CI: 0.1%-0.4%), and was lower than the prevalence of the other 2 groups (P < .01). There was no difference in prevalence of hyperthyroidism in each group. CONCLUSIONS: Thyroid nodules are the most easily detectable thyroid disease. These have a lower prevalence in the high-iodine group. The prevalence of most thyroid diseases is lowest for a UIC ranging from 100 to 299 µg/L. This serves as a reference for health policy-making with respect to iodine levels. Further studies on this topic should be carried out according to sufficient thyroid cancer data.

tert-Butyl 6-amino-5-cyano-2-(2-meth-oxy-eth-yl)nicotinate.

The title compound, C(14)H(19)N(3)O(3), was synthesized by the reaction of 3-meth-oxy-propionitrile, tert-butyl bromo-acetate and eth-oxy-methyl-enemalononitrile. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into chains propagating along the b axis.