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Aims. We present secular multiwavelength broadband photometry, spanning over 93 days, performed at the Yaoan High Precision Telescope on comet 64P/Swift-Gehrels in its 2018–2019 apparition. Our aim is to study its dust activity, coma properties, and the accidentally discovered mini-outburst. Methods. We used aperture photometry to measure the Afρ value and correct the back-scattering effect based on phase angle. We deployed azimuthally averaged image enhancement methods to identify the coma morphology and the outburst. Secular color measurement was also conducted on the comet. Results. We identified a −0.5 mag mini-outburst around January 3, 2019, with coma morphology study showing an obvious dust jet feature strengthened during the outburst. The maximum A(0)fρ value of 64P/Swift-Gehrels recorded is 313 cm at the top of the fitted curve and 334 cm at the outburst event. Both volatile-driven pressure mechanisms and nonvolatile-driven mechanisms could be the major explanation for the outburst. We obtain a mean color B − V = 0.68 ± 0.03 and V − R = 0.08 ± 0.01. The B − V color is similar to the mean value for Jupiter Family comets, but the V − R color turns out to be bluest among all the recorded short-period comets. The cause of this anomaly remains unknown.

The different joint arrangements resulting from different segmental assemblies between adjacent rings may inevitably give rise to the interaction for staggered jointed lining, which is cruc...

The purpose of this study was to identify differentially expressed genes and analyze biological processes related to leukemia. A meta-analysis was performed using the Rank Product package of Gene Expression Omnibus datasets for leukemia. Next, Gene Ontology-enrichment analysis and pathway analysis were performed using the Gene Ontology website and Kyoto Encyclopedia of Genes and Genomes. A protein-protein interaction network was constructed using the Cytoscape software. Using the Rank Product package for leukemia, we identified a total of 1294 differentially expressed genes, 357 of which were not involved in individual differentially expressed genes. Gene Ontology-enrichment analyses showed that these 357 genes were enriched in biological processes such as mRNA metabolism, RNA splicing, and mRNA processing. Pathway-enrichment analysis showed that the genes were involved in the intestinal immune network for IgA production, endocytosis, and the mitogen-activated protein kinase signaling pathway. The protein-protein interaction network indicated that HRAS, CD44, STAT1, SMAD2, and COPS5 were important in many interactions. Our study revealed genes that were consistently differentially expressed in leukemia, as well as the biological pathways and protein-protein interaction network associated with these genes.

The goal of the study reported here was to determine the developmental potential of cloned embryos using two donor cells [fetal-derived fibroblast cells (FFCs) and adult-derived fibroblast cells (AFCs)] and in vitro fertilization (IVF) embryos with oocytes obtained by ovum pickup (OPU) and the relationship between timing of first cleavage and pregnancy or calving rate. Heifers were subjected to OPU once weekly. In total, 1558 oocytes were recovered from 2033 follicles, a mean of 7.8±0.4 oocytes per session per animal. Mean oocyte production was similar not in quantity but in quality (proportion of each oocyte grade) among groups [FFC-nuclear transfer (NT), AFC-NT and IVF groups]. These oocytes were then subjected to somatic cell nuclear transfer (SCNT) and IVF. Although reconstructed embryos initiated cleavage sooner when the donor cells were from FFCs versus AFCs, cleavage of embryos in the IVF group occurred 1 and 2 h earlier than that in the FFC-NT group and the AFC-NT group. However, in vitro development to blastocyst and the pregnancy rates at Day 90 of gestation were different between donor cell types; four cloned calves were obtained and survived for more 6 months. Although in terms of cleavage rates and blastocyst rates, there were no significant differences between IVF and FFC-NT groups, for in vivo development, the efficiency of IVF was higher than that of SCNT. In conclusion, the timing of first cleavage, pregnancy and calving rate differs by the source of donor fibroblast cells, and shorter timing of first cleavage may imply a higher pregnancy or calving rate. The oocytes obtained by OPU can be used as recipients for SCNT.

We have used our analysis of γ-γ-γ data (5.7 × 1011 triples and higher folds) taken with Gammasphere from prompt γ rays emitted in the spontaneous fission of 252Cf to study the collective bands in 104,106,108Mo. The one-phonon and two-phonon γ-vibrational bands and known two-quasiparticle bands in neutron-rich 104,106Mo were extended to higher spins. The one-and two-phonon γ-vibrational bands have remarkably close energies for transitions from the same spin states and identical moments of inertia. Several new bands are observed and are proposed as quasiparticle bands in 104,106Mo, along with the first β-type vibrational band in 106Mo. The quasiparticle bands have essentially constant moments of inertia near the rigid-body value that indicate blocking of the pairing interaction. Candidates for chiral doublet bands in 106Mo are strong. These are the first reported chiral vibrational bands in an even-even nucleus.

High-spin states in neutron-rich 106Mo were investigated by detecting the prompt γ-rays in the spontaneous fission of 252Cf with Gammasphere. Several new bands are observed. Two sets of ΔI = 1 bands in 106Mo are found to have all the characteristics of a new class of chiral vibrational doublets. Tilted axis cranking calculations support the chiral assignment and indicate that the chirality is generated by neutron h11/2 particle and mixed d5/2, g7/2 hole coupled to the short and long axis, repectively.

High spin states in the odd–odd nucleus 122Cs have been studied by in-beam γ-ray spectroscopy with a 107Ag(19F,1p3n) fusion-evaporation reaction at a beam energy of 85 MeV. A previously known πh11/2 ⊗ νh11/2 yrast band was confirmed and its spin I was re-examined. A ΔI = 2 band was identified, which together with another known ΔI = 2 band forms a side band of the πh11/2 ⊗ νh11/2 yrast band. The two observed πh11/2 ⊗ νh11/2 bands are proposed as a pair of chiral doublet bands in 122Cs based on a systematic comparison with those in the neighbouring odd–odd Cs isotopes, as well as the relativistic mean field and the triaxial particle-rotor-model calculations.

Several metal plates with different thickness including copper, iron, aluminum, and stainless steel have been drilled in the surroundings of air and water, respectively, by a Q-switched pulsed Nd:yttrium–aluminum–garnet laser. It is observed that for the same metal plate less energy is needed to drill a hole in water than that in air, and the surface morphology of hole drilled in water is improved greatly than that in air by comparison of the scanning electron micrographs. The underlying mechanisms behind the efficiency and quality enhancement in water are further investigated by means of optical beam deflection technique. The experimental results show that due to the water confinement the peak amplitude and duration of the laser-ablation-generated impact underwater is much larger than that in air. During the underwater laser drilling, besides laser ablation effect, both the first and second liquid-jet-induced impulses by cavitation bubble collapse in the vicinity of a solid boundary are also observed and...

Neutron-rich nuclei populated in spontaneous fission are providing new tests for microscopic models. The neutron-rich 104–108 Mo, 108–114 Ru and 112–116 Pd exibit a variety of rapidly changing collective band structures to high spins. The first evidence for chiral band doublets in any even-even nucleus are reported.

Push-out tests were widely used to determine the shear bearing capacity and shear stiffness of shear connectors in steel-concrete composite structures. The finite element method was one efficient alternative to push-out testing. This paper focused on a simulation analysis of the interface between concrete slabs and steel girder flanges as well as the interface of the shear connectors and the surrounding concrete. A cohesive zone model was used to simulate the tangential sliding and normal separation of the interfaces. Then, a zero-thickness cohesive element was implemented via the user-defined element subroutine UEL in the software ABAQUS, and a multiple broken line mode was used to define the constitutive relations of the cohesive zone. A three-dimensional numerical analysis model was established for push-out testing to analyze the load-displacement curves of the push-out test process, interface relative displacement, and interface stress distribution. This method was found to accurately calculate the shear capacity and shear stiffness of shear connectors. The numerical results showed that the multiple broken lines mode cohesive zone model could describe the nonlinear mechanical behavior of the interface between steel and concrete and that a discontinuous deformation numerical simulation could be implemented.

Circular piezoelectric bimorph has been successfully used in numerous types of microdevices, such as actuators for flowcontrol applications, transducers for acoustic applications, and in locomotion of robotic systems, energy harvesting and active structural health monitoring applications. Recently, the concept of the functionally graded material (FGM) is introduced to improve properties and increase lifetime by selectively grading the elastic, piezoelectric, and/or dielectric properties along the thickness of a piezoceramic. However, even for the simple case of homogeneous circular piezoelectric geometry, analytical treatments are severely limited. This study established an axisymmetric and isoparametric graded element to model the functionally graded circular piezoelectric plates. All the material properties including elastic coefficients, piezoelectric coefficients, dielectric parameters and mass density are graded in the element and interpolated using the shape functions, which is also used to render the displacements and electric potential distribution in the element. Both static and dynamic cases can be considered in this element. MATLAB is used to implement the whole FEM code and gives some numerical examples to demonstrate the presented method.

New levels in the neutron-rich ${}^{113}\mathrm{Ru}$ nucleus have been identified by analyzing $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence events following the spontaneous fission of ${}^{252}\mathrm{Cf}$ with the Gammasphere detector array. A rotational band going up to 3.6 MeV is identified and is proposed to be built on the intruder $\ensuremath{\nu}{\mathrm{h}}_{11/2}$ orbital going up to $(31/2)\ensuremath{\Elzxh}.$ A few states of a possible signature partner are also observed.

Levels in the neutron-rich, odd-mass ${}^{107}\mathrm{Ru}$ nucleus have been reinvestigated with Gammasphere by measuring high-fold, prompt coincidence events following spontaneous fission of ${}^{252}\mathrm{Cf}.$ The ground state band has been extended up to $\frac{27}{2}\ensuremath{\Elzxh}.$ The structure associated with the ${h}_{11/2}$ excitation has been confirmed and extended to higher spin. The ${h}_{11/2}$ band head has been established to lie at 301.8 keV. These results clear up differences between our earlier work and results from another experiment published recently. A new collective band based on a ${9/2}^{\ensuremath{-}}$ level has been identified for the first time. Some distinct features of the level scheme are discussed.

A preliminary report of the results of a specific, quantitative method of rapid (4.5 hours) beta human chorionic gonadotropin radioimmunoassay (hCG-RIA) of urine voided at any time for diagnosing early pregnancy is presented. In 50 cases neither false positive nor false negative reactions were noted. The beta-hCG-RIA method showed positive results as early as the 25th day of the menstrual cycle. This method has also proven helpful in the early diagnosis of suspected ectopic pregnancies with negative pregnancy tests, in the detection of incomplete abortion, and in the follow-up examination of treated patients with hydatidiform mole or choriocarcinoma. The urine voided at any time could be used as specimens for the rapid beta-hCG-RIA which could be completed in 4.5 hours in the laboratory. The assay was clinically useful because of its shorter incubation time and the possibility of taking the urine as samples in the test instead of the serum specimen. (author's modified)