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In this paper, we study the stability problem for the Einstein metrics on Sasaki Einstein and on complete nearly parallel [Formula: see text] manifolds. In the Sasaki case we show linear instability if the second Betti number is positive. Similarly, we prove that nearly parallel [Formula: see text] manifolds with positive third Betti number are linearly unstable. Moreover, we prove linear instability for the Berger space [Formula: see text] which is a [Formula: see text]-dimensional homology sphere with a proper nearly parallel [Formula: see text] structure.

We study the linear stability of Einstein metrics of Riemannian submersion type. First, we derive a general instability condition for such Einstein metrics and provide some applications. Then we study instability arising from Riemannian product structures on the base. As an application, we estimate the coindex of the Einstein metrics constructed in \cite{WZ90} and \cite{Wan92}. Finally, we investigate more closely the linear stability of Einstein metrics from circle bundle constructions and obtain a rigidity result for linearly stable Einstein metrics of this type., Comment: 23 pages

报道4例使用α干扰素治疗后发生HBsAg血清学转换而HBeAg仍阳性的乙型肝炎血清学标志物少见模式，并复习相关文献，探讨出现这种现象的可能原因。.

The aim of this study is to explore the pathogenesis of granulomatous lobular mastitis (GLM) via pathology and molecular biology. This single-center study included 28 female patients who received a diagnosis of pathologically confirmed GLM from January 2020 to September 2020 at Dongzhimen Hospital of Beijing University of Chinese Medicine. Tissue samples and serum were collected during radical surgery. Western blot and immunohistochemistry were employed to determine caspase-1 and gasdermin D (GSDMD). Transmission electron microscopy (TEM) was used to observe the ultrastructure of cells. Finally, the results were analyzed. The expression of activated GSDMD and caspase-1 were all increased in the lesion group (P0.05). The TEM results showed clear features of pyroptosis. We concluded that pyroptosis was important in the development of GLM and inhibitad apoptosis to some degree. The inhibition of pyroptosis response may help to discover new drugs for GLM.

X. G. Cao, E. J. Kim, K. Hagel, M. Barbui, J. Gauthier, S. Wuenschel, G. Giuliani, M. R. D. Rodriguez, H. Zheng, M. Huang, A. Bonasera, R. Wada, N. Blando, G. Q. Zhang, C. Y. Wong A. Staszczak, Z. X. Ren, Y. K. Wang, S. Q. Zhang, J. Meng, J. B. Natowitz, Exclusive measurements for α and α conjugate exit channels are carried out for 35 MeV/nucleon 28Si induced reactions. Systematic analyses of these channels reveal high energy resonance structures in 7 de-excitation channels. The resonances are compared with results of several recent theoretical calculations for toroidal high-spin isomers. The possible underlying physics of these observations are discussed.

The aim of this paper is to develop a micromechanical method based on a proper representative volume element to investigate the effective coefficients and fully coupled electromagnetoelastic responses for three-dimensional smart composites. Relations between the particulate volume fraction, effective moduli, piezoelectric coefficients, and dielectric coefficients are investigated for the composites. Their effective responses, with account of electric, magnetic, and displacement fields, are analyzed. The numerical results obtained indicate that the overall strains of piezoelectric-piezomagnetic composites strongly depend on variations of the electric and magnetic fields.

Background Global simultaneous recording of activation during atrial fibrillation (AF) can elucidate underlying mechanisms contributing to AF maintenance. A better understanding of these mechanisms may allow for a personalised ablation strategy to treat persistent AF. Purpose To characterise left atrial endocardial activation patterns during AF using a novel non-contact dipole density mapping. Methods Activation patterns were characterised into three sub-types: (i) focal with centrifugal activation (FCA); (ii) localised rotational activation (LRA); (iii) localised irregular activation (LIA). Continuous activation patterns were quantified and distributed in the left atrium. Results A total of 144 persistent AF segments with 1068 activation patterns from 25 patients were analysed. The most common pattern was LIA (63%), which consist of four disparate features: slow conduction (45%), pivoting (30%), collision (16%) and acceleration (7%). LRA was the second commonest pattern (20%). FCA (17%) arose frequently from the PVs/ostia. Continuous AF activations comprise multiple combinations of FCA, LRA and LIA, transitioning from one to the next without a discernible order. Preferential conduction areas were typically seen in mid-anterior (48%) and lower-posterior (40%) walls where dominant activations were made up of LRA and LIA. Conclusion AF is characterised by heterogenous activation patterns that vary between individuals. Clinical implications of individualised ablation strategies guided by dipole density mapping will have to be determined. Acknowledgement/Funding None

The nuclear chiral conundrum with crossing twin bands is investigated with three-dimensional tilted axis cranking covariant density functional theory in a fully self-consistent and microscopic way. The energy spectra and electromagnetic transition strengths for bands 1 and 2 in Ag-106 are well reproduced with two distinct configurations with two and four quasiparticles, respectively. For the four-quasiparticle configuration, a chiral vibrational band on top of band 2 is expected due to the soft Routhian curves. Therefore, it provides a microscopic and solid solution for the chiral conundrum in Ag-106. It also paves the way for understanding similar chiral structure in other nuclei in the future..

Digit ratio, particularly the second to fourth digit ratio (2D:4D), is fixed before birth and is related to male sexual orientation; moreover, ethnicity may affect the digit ratio. We take photocopies of both hands of 308 men of Han ethnicity, and we explored the relationship between the 2D:4D ratio and sexual orientation among the three groups (121 homosexual men, 50 bisexual men and 177 heterosexual men). The results showed: (a) the digit ratio of the men presented the trend as follows: 2D:3D

With the large number of construction and commercial operation of trough solar thermal power station, the performance test standard and test method of trough solar power station are still missing and imperfect. For the heat storage heat exchange system of trough type solar thermal power station, the index system of heat exchange efficiency, heat storage time and heat collection efficiency are constructed, and the work contents of performance test and technical index are improved. Learn from the idea and concept of performance acceptance test of thermal power generation equipment system in power industry, combined with many years of relevant work experience. It is expected to bring reference and guidance to relevant technical personnel and peers.

In order to improve the load regulation capability of the power grid, verification of the minimum boundary output characteristics of deep peak regulation of coal-fired units was carried out. Considering the safety, stability, environmental protection, and energy saving indicators, the minimum output stability evaluation method was discussed in a 300MW coal-fired unit, and the ultra-low combustion stability target of 25% of rated load was completed. This has important guiding significance for approving the output characteristics of units, carrying out precise load regulation, and expanding new energy consumption.

The experimental excitation function for the $7\ensuremath{\alpha}$ de-excitation of $^{28}\mathrm{Si}$ nuclei excited to high excitation energies in the collisions of 35 MeV/nucleon $^{28}\mathrm{Si}$ with $^{12}\mathrm{C}$ reveals resonance structures. The possibility that these structures may indicate the population of toroidal high-spin isomers such as those predicted by a number of recent theoretical calculations is discussed and the need for further investigations is emphasized.

The observed shears bands in $^{198}\mathrm{Pb}$ and $^{199}\mathrm{Pb}$ are investigated within the framework of tilted axis cranking covariant density functional theory, and the separable pairing force is adopted to consider the pairing correlations. The energy spectra, total angular momenta, and transition probabilities agree well with the experimental data. The bandhead energy differences are reproduced satisfactorily without any ad hoc renormalizations when the pairing correlations are taken into account. The angular momentum vectors are discussed in detail to analyze the pairing effects on magnetic rotations.

New ligand precursors with different pendent alky chain length were obtained in a single step by reacting appropriate 1-alkyl-2-methyl-1H-imidazoles with chloroacetone in THF at 80 °C overnight. Zwitterionic palladium complexes were prepared by reacting PdCl2 with these new imidazole derivatives in DMF with the presence of pyridine and Cs2CO3 as base at room temperature for 5 h. These new compounds were characterized by 1H and 13C{1H} NMR spectroscopy, elemental analysis, and electrospray ionization mass spectrometry. They were effectively applied as recyclable catalysts for mediating Mizoroki–Heck reactions in ionic liquids. Transmission emission microscopy revealed that palladium nanoparticles were formed during the catalytic process.

The possibility that a fraction of the dark matter is comprised of massive compact halo objects (MACHOs) remains unclear, especially in the 20-100 $M_{\odot}$ window. MACHOs could make up binaries, whose mergers may be detected by LIGO as gravitational wave events. On the other hand, the cosmological origin of fast radio burst (FRBs) has been confirmed. We investigate the possibility of detecting fast radio bursts (FRBs) gravitational lensed by MACHO binaries to constrain their properties. Since lensing events could generate more than one images, lensing by binaries could cause multiple-peak FRBs. The angular separation between these images is roughly $10^{-3}$ mas, which is too small to be resolved. The typical time interval between different images is roughly 1 millisecond (ms). The flux ratio between different images is roughly from 10 to $10^3$. With the expected detection rate of $10^4$ FRBs per year by the upcoming experiments, we could expect five multi-peak FRBs observed per year with time interval larger than 1 ms and flux ratio less than $10^3$ if the fraction of dark matter in MACHOs is $f\sim0.01$. A null search multiple-peak FRBs for time interval larger than 1 ms and flux ratio less than $10^3$ with $10^4$ FRBs would constrain the fraction $f$ of dark matter in MACHOs to $f, 6 pages, 3 figures, 3 tables, accepted for publication in A&A, final version after language editing

Resonance structures are observed in the excitation function of the 7α de-excitation of 28Si nuclei are observed in the collisions of 35 MeV/nucleon 28Si with 12C. These structures may indicate that toroidal high-spin isomers such as those predicted by recent theoretical calculations are populated.

To overcome the hysteresis of a tip/tilt mirror(TTM)in an adaptive optical system and to improve its linearity and control precision,this paper researches the nonlinear effects of the TTM.A compensation method based on the frequency-dependent Mutified-Prandtl-Ishlinskii(MPI)model is proposed for online adaptive inverse compensation of the hysteresis nonlinearity of the TTM.By combining with PID feedback control algorithm,an adaptive inverse feedforward composite control algorithm is proposed.In which,the adaptive inverse feedforward overcomes the hysteresis curve changes due to the frequency factors,and the PID algorithm improves the overall control performance.A second-order model of the TTM is established to estimate the output of the TTM system,which solves the reference signals of the MPI model,avoids adding extra feedforward sensors,and ensures the utilization of light energies.Experiment results indicate that this algorithm effectively solves the problemof hysteresis nonlinearity of the TTM,the 15 Hz hysteresis ratio of the TTM fells from 24.28% to1.17%,and the linearity is improved by about 95%.As compared with the traditional PID algorithm,the control precision has increased by about 60%.It concludes that this composite control algorithm can compensate the hysteresis nonlinearity of the TTM effectively,and the control precision of the TTM is improved in adaptive optical systems.

The emergence of consumer level capturing and display devices for 360 degree video creates new and promising segments in entertainment, education, professional training, and other markets. In order to avoid market fragmentation and ensure interoperability of 360 degree video ecosystems, industry and academia cooperate in standardization efforts in this field. In the video coding domain, 360 degree video invalidates many established procedures, e.g., concerning evaluation of the visual quality, while the specific content characteristics offer potential for higher compression efficiency beyond the current standards. Likewise, 360 degree video puts stricter demands on the system level aspects of transmission but may also offer the potential to enhance existing transport schemes. The Joint Collaborative Team on Video Coding (JCT-VC) as well as the Joint Video Exploration Team (JVET) already started investigations into 360 degree video coding while numerous activities in the Systems subgroup of the Moving Picture Experts Group (MPEG) started to investigate application requirements and delivery aspects of 360 degree video. This paper reports on the current status of the outlined standardization efforts.

A separable form of the Gogny pairing force is implemented in tilted axis cranking covariant density functional theory for the description of rotational bands in open shell nuclei. The developed method is used to investigate the yrast sequence of $^{109}\mathrm{Ag}$ for an example. The experimental energy spectrum, angular momenta, and electromagnetic transition probabilities are well reproduced by taking into account pairing correlations with the separable pairing force. An abrupt transition of the rotational axis from the long-intermediate plane to the long-short one is obtained and discussed in detail.

AFP-producing gastric cancer(AFPGC) and hepatoid adenocarcinoma of the stomach (HAS) are two special subtypes of gastric cancer. There are both correlation and difference between them. AFPGC is usually identified as primary gastric cancer with serum AFP level more than 20 ng/ml or showed AFP positive staining by immunohistochemistry. The diagnosis of HAS is mainly dependent on the pathological character of hepatocellular carcinoma-like differentiation of gastric cancer. The morbidity of AFPGC and HAS are rather low, especially the incidence of HAS is about 1%. The prognoses of these two subtypes are poorer than that of common gastric adenocarcinoma, due to a high incidence rate of liver metastasis and lymph node metastasis. With the development of next-generation sequencing and other genomic technologies, gastric cancers, including these two rare subtypes, are now being investigated in more detail at the molecular level. Treatment remains the biggest challenge, early diagnosis and radical resection can dramatically improve patients'prognosis. Monitoring serum AFP and abdominal imaging examination during follow-up is important for early detection of liver metastasis. In combination with local treatment methods such as transarterial chemoembolization and radiofrequency ablation of liver may further extend patients'survival time. Targeted therapy owes a great potential value in the future.产甲胎蛋白胃癌(AFPGC)和胃肝样腺癌(HAS)是胃癌中较为特殊的2种类型，它们之间既有联系又有区别。临床上往往将AFPGC定义为血清AFP20 ng/ml或者免疫组化AFP阳性的胃癌，HAS的诊断主要依靠病理形态学，即具有肝细胞癌分化形态特征的原发性胃癌。AFPGC和HAS的发病率均很低，尤其是HAS，为1%左右，均易发生肝转移和淋巴结转移，预后显著差于普通胃腺癌。随着高通量测序的开展，在胃癌分子分型逐渐明确的同时，人们对AFPGC和HAS的分子背景也有了一定的认识。目前，有效治疗仍是AFPGC和HAS的最大挑战，早期诊断和根治性手术切除可以很大程度地改善患者的预后，术后密切监测血清AFP水平和腹部影像学表现，有助于及早发现肝转移，而联合肝动脉介入化疗和射频消融等局部治疗可以改善患者的预后。靶向治疗在AFPGC和HAS治疗中有着广阔的前景。.