Study Majorana Neutrino Contribution to B-meson Semi-leptonic Rare Decays

B meson semi-leptonic rare decays are sensitive to new physics beyond standard model. We study the $B^{-}\to \pi^{-}\mu^{+}\mu^{-}$ process and investigate the Majorana neutrino contribution to its decay width. The constraints on the Majorana neutrino mass and mixing parameter are obtained from this decay channel with the latest LHCb data. Utilizing the best fit for the parameters, we study the lepton number violating decay $B^{-}\to \pi^{+}\mu^{-}\mu^{-}$, and find its branching ratio is about $6.4\times10^{-10}$, which is consistent with the LHCb data reported recently.Comment: 10 pages, 3 figure

Deformation and orientation effects in the driving potential of the dinuclear model

A double-folding method is used to calculate the nuclear and Coulomb interaction between two deformed nuclei with arbitrary orientations. A simplified Skryme-type interaction is adopted. The contributions of nuclear interaction and Coulomb interaction due to the deformation and orientation of the nuclei are evaluated for the driving potential used in the description of heavy-ion fusion reaction. So far there is no satisfactory theory to describe the evolution of the dynamical nuclear deformation and orientations during the heavy-ion fusion process. Our results estimated the magnitude of above effects.Comment: 15 pages, 6 figures, Accepted by Eur. Phys. Jour.

(2,2′-Bipyridine-κ2 N,N′){N-[(2-oxidonaphthalen-1-yl-κO)methyl­idene]-l-valinato-κO}copper(II) trihydrate

In the title complex, [Cu(C16H15NO3)(C10H8N2)]·3H2O, the CuII atom is five coordinated by O,N,O′-donor atoms of the Schiff base ligand and by two N atoms of the 2,2′-bipyridine ligand in a distorted square-pyramidal geometry. In the crystal, mol­ecules are linked into a two-dimensional network parallel to (011) by O—H⋯O hydrogen bonds

Phytoestrogen -zearalanol ameliorates memory impairment and neuronal DNA oxidation in ovariectomized mice

OBJECTIVE: The aim of this study was to evaluate the effect of a novel phytoestrogen, α-Zearalanol, on Alzheimer's disease-related memory impairment and neuronal oxidation in ovariectomized mice. METHODS: Female C57/BL6 mice were ovariectomized or received sham operations and treatment with equivalent doses of 17β-estradiol or α-Zearalanol for 8 weeks. Their spatial learning and memory were analyzed using the Morris water maze test. The antioxidant enzyme activities and reactive oxygen species generation, neuronal DNA oxidation, and MutT homolog 1 expression in the hippocampus were measured. RESULTS: Treatment with 17β-estradiol or α-Zearalanol significantly improved spatial learning and memory performance in ovariectomized mice. In addition, 17β-estradiol and α-Zearalanol attenuated the decrease in antioxidant enzyme activities and increased reactive oxygen species production in ovariectomized mice. The findings indicated a significant elevation in hippocampi neuronal DNA oxidation and reduction in MutT homolog 1 expression in estrogen-deficient mice, but supplementation with 17β-estradiol or α-Zearalanol efficaciously ameliorated this situation. CONCLUSION: These results demonstrate that α-Zearalanol is potentially beneficial for improving memory impairments and neuronal oxidation damage in a manner similar to that of 17β-estradiol. Therefore, the compound may be a potential therapeutic agent that can ameliorate neurodegenerative disorders related to estrogen deficiency

(E)-2-[2-(4-Chloro­benzyl­idene)hydrazin­yl]-4-[3-(morpholin-4-ium-4-yl)propyl­amino]­quinazolin-1-ium bis­(perchlorate)

In the title compound, C22H27ClN6O2 2+·2ClO4 −, the mol­ecule adopts an E conformation about the C=N double bond. The quinazoline ring is approximately planar, with an r.m.s. deviation of 0.0432 Å, and forms a dihedral angle of 5.77 (4)° with the chloro­phenyl ring. The crystal packing features N—H⋯O hydrogen bonds

Incremental Dense Reconstruction from Monocular Video with Guided Sparse Feature Volume Fusion

Incrementally recovering 3D dense structures from monocular videos is of paramount importance since it enables various robotics and AR applications. Feature volumes have recently been shown to enable efficient and accurate incremental dense reconstruction without the need to first estimate depth, but they are not able to achieve as high of a resolution as depth-based methods due to the large memory consumption of high-resolution feature volumes. This letter proposes a real-time feature volume-based dense reconstruction method that predicts TSDF (Truncated Signed Distance Function) values from a novel sparsified deep feature volume, which is able to achieve higher resolutions than previous feature volume-based methods, and is favorable in large-scale outdoor scenarios where the majority of voxels are empty. An uncertainty-aware multi-view stereo (MVS) network is leveraged to infer initial voxel locations of the physical surface in a sparse feature volume. Then for refining the recovered 3D geometry, deep features are attentively aggregated from multiview images at potential surface locations, and temporally fused. Besides achieving higher resolutions than before, our method is shown to produce more complete reconstructions with finer detail in many cases. Extensive evaluations on both public and self-collected datasets demonstrate a very competitive real-time reconstruction result for our method compared to state-of-the-art reconstruction methods in both indoor and outdoor settings.Comment: 8 pages, 5 figures, RA-L 202

Mechanistic insights from structure of Mycobacterium smegmatis topoisomerase I with ssDNA bound to both N- and C-terminal domains

Type IA topoisomerases interact with G-strand and T-strand ssDNA to regulate DNA topology. However, simultaneous binding of two ssDNA segments to a type IA topoisomerase has not been observed previously. We report here the crystal structure of a type IA topoisomerase with ssDNA segments bound in opposite polarity to the N- and C-terminal domains. Titration of small ssDNA oligonucleotides to Mycobacterium smegmatis topoisomerase I with progressive C-terminal deletions showed that the C-terminal region has higher affinity for ssDNA than the N-terminal active site. This allows the C-terminal domains to capture one strand of underwound negatively supercoiled DNA substrate first and position the N-terminal domains to bind and cleave the opposite strand in the relaxation reaction. Efficiency of negative supercoiling relaxation increases with the number of domains that bind ssDNA primarily with conserved aromatic residues and possibly with assistance from polar/basic residues. A comparison of bacterial topoisomerase I structures showed that a conserved transesterification unit (N-terminal toroid structure) for cutting and rejoining of a ssDNA strand can be combined with two different types of C-terminal ssDNA binding domains to form diverse bacterial topoisomerase I enzymes that are highly efficient in their physiological role of preventing excess negative supercoiling in the genome

The research of parallel to the grain compression performance test of laminated glued bamboo-wood composites

Istraživanje stlačivosti kompozita bambus-drvo predstavlja osnovu za izbor materijala za prednapregnute grede od bambusa i drveta i drugih komponenti čija se stlačivost uglavnom dijeli s kompozitima od lijepljenog bambusa i drveta. Odabrane su četiri vrste drveta i dvije vrste bambusa za 22 grupe (6 uzoraka u svakoj grupi) podijeljene u 4 serije za ispitivanje čimbenika koji utječu na vrstu materijala bambus/drvo, kao što su sastav, debljina ploče sloja (layer plate), i tipovi postavljanja lamela (lamina lay-ups type). Uspoređivani su i analizirani tlačna čvrstoća, modul elastičnosti, duktilnost i mehanizmi kvara. Rezultati su pokazali da je do loma uglavnom dolazilo zbog kosog smika (oblique shear failure), savijanja laminata, dok su se krajnji lokalni tlak i lom zbog uvijanja događali manje često. Tlačna čvrstoća bambusa bila je 1,5 ÷ 2 puta veća nego tlačna čvrstoća drveta. Njihov je modul elastičnosti sličan zbog čega se uobičajeno koriste u temeljima. Nakon sastavljanja, tlačna se čvrstoća povećala. Nakon sastavljanja s lijepljenim bambusom, povećala se za 1,26 ÷ 32,05 %, a s rekonsolidiranim bambusom (nanovo učvršćenim) se povećala za 0,80 ÷ 45,86 %. Kompoziti bambus-drvo imaju visoku čvrstoću i dobru duktilnost, što može zadovoljiti tehničke potrebe.Research of bamboo-wood composites compression performance provides a basis for material selections for prestressed glued bamboo-wood beams and other components whose compression is mainly shared by glued bamboo-wooden composites. Four kinds of wood and two kinds of bamboo were selected to comprise 22 groups (6 specimens each group) divided into 4 batches to study the influence factors on bamboo/wooden material type; factors such as composition pattern, layer plate thickness, and lamina lay-ups type. Compressive strength, elasticity modulus, ductility, and failure mechanisms were all compared and analysed. Results showed that failure modes were mainly oblique shear failure, laminates bending failure, laminates tackless failure, while the end local pressure and overall bending failure occured less frequently. Compressive strength of bamboo was 1,5 ÷ 2 times higher than that of wood. Elastic modulus of the two was similar, which makes them commonly used in foundations. After being compounded, compressive strength improved. After being combined with glued bamboo, it increased by 1,26 ÷ 32,05 %, and it increased by 0,80 ÷ 45,86 % with reconsolidated bamboo. Bamboo-wood composites have high strength and good ductility, which can meet engineering requirements

Polar domain structural evolution under electric field and temperature in the (Bi0.5 Na0.5)TiO3 -0.06BaTiO3 piezoceramics

Lead‐free bismuth sodium titanate and related compounds are of great interest as promising candidates for piezoelectric applications. However, the full understanding of this family of materials is still a challenge partly because of their structural complexity and different behaviors with or without the application of an external electric field. Here, piezoresponse force microscopy is used to gain insight into the mesoscopic‐scale domain structure of the morphotropic phase boundary (MPB) composition of (1‐x)Bi0.5Na0.5TiO3‐xBaTiO3 solid solution at x = 0.06 (abbreviated as BNT‐6BT). The evolution of the domains with the changes of the electric field and temperature has been thoroughly examined in conjunction with the crystal structure analysis and dielectric studies. It is found that ferroelectric domains with size of hundreds of nanometers are embedded in a relaxor state without visible domains on a mesoscopic scale, which are considered to contribute to the tetragonal and cubic phases in the material, respectively. Temperature‐independent domain configuration is observed in the unpoled sample from room temperature to 200°C. While, temperature‐dependent domain configuration is observed in the poled sample. The homogenously poled state breaks into the mixed domain configuration containing polydomain structure and invisible state around the so‐called depoling temperature. The structural changes on different length scales are also discussed. This work provides an in‐depth understanding of the structural and domain changes under an electric field and the temperature‐dependent domain evolution in both unpoled and poled states in the BNT‐BT solid solution of the MPB composition