45 research outputs found
Some symmetry properties of spin currents and spin polarizations in multi-terminal mesoscopic spin-orbit coupled systems
We study theoretically some symmetry properties of spin currents and spin
polarizations in multi-terminal mesoscopic spin-orbit coupled systems. Based on
a scattering wave function approach, we show rigorously that in the equilibrium
state no finite spin polarizations can exist in a multi-terminal mesoscopic
spin-orbit coupled system (both in the leads and in the spin-orbit coupled
region) and also no finite equilibrium terminal spin currents can exist. By use
of a typical two-terminal mesoscopic spin-orbit coupled system as the example,
we show explicitly that the nonequilibrium terminal spin currents in a
multi-terminal mesoscopic spin-orbit coupled system are non-conservative in
general. This non-conservation of terminal spin currents is not caused by the
use of an improper definition of spin current but is intrinsic to
spin-dependent transports in mesoscopic spin-orbit coupled systems. We also
show that the nonequilibrium lateral edge spin accumulation induced by a
longitudinal charge current in a thin strip of \textit{finite} length of a
two-dimensional electronic system with intrinsic spin-orbit coupling may be
non-antisymmetric in general, which implies that some cautions may need to be
taken when attributing the occurrence of nonequilibrium lateral edge spin
accumulation induced by a longitudinal charge current in such a system to an
intrinsic spin Hall effect.Comment: 11 pages, 6 figure
Kinetic magnetoelectric effect in a 2D semiconductor strip due to boundary-confinement induced spin-orbit coupling
In a thin strip of a two-dimensional semiconductor electronic system,
spin-orbit coupling may be induced near both edges of the strip due to the
substantial spatial variation of the confining potential in the boundary
regions. In this paper we show that, in the presence of boundary-confinement
induced spin-orbit coupling, a longitudinal charge current circulating through
a 2D semiconductor strip may cause \textit{strong} non-equilibrium spin
accumulation near both edges of the strip. The spins will be polarized along
the normal of the 2DEG plane but in opposite directions at both edges of the
strip. This phenomenon is essentially a kinetic magnetoelectric effect from the
theoretical points of view, but it manifests in a very similar form as was
conceived in a spin Hall effect.Comment: 7 pages, 4 fig
Identification and validation of prognostic and immunotherapeutic responses in esophageal squamous carcinoma based on hypoxia phenotype-related genes
The study aimed to investigate the clinical significance of the interaction between hypoxia and the immune system in esophageal squamous cell carcinoma (ESCC) microenvironment. A comprehensive evaluation of 13 hypoxia phenotype-related genes (HPRs) was conducted using data from TCGA-ESCC and two GEO cohorts. Three distinct HPRclusters were identified, and the HPRscore was established as an independent prognostic factor (p = 0.001), with higher scores indicating poorer prognosis. The HPRscore was validated in various immunotherapy cohorts, demonstrating its efficacy in evaluating immunotherapy and chemotherapy outcomes. Additionally, phenome-wide association study (PheWAS) analysis showed that PKP1 had no significant correlation with other traits at the gene level. PKP1 was identified as a potential prognostic marker for ESCC, with upregulated expression observed in ESCC patients. In vitro experiments showed that the knockdown of PKP1 inhibited ESCC cell proliferation and migration. These findings suggest that the novel HPRscore and PKP1 may serve as prognostic tools and therapeutic targets for ESCC patients
Circulating Monocytes Act as a Common Trigger for the Calcification Paradox of Osteoporosis and Carotid Atherosclerosis via TGFB1-SP1 and TNFSF10-NFKB1 Axis
BackgroundOsteoporosis often occurs with carotid atherosclerosis and causes contradictory calcification across tissue in the same patient, which is called the âcalcification paradoxâ. Circulating monocytes may be responsible for this unbalanced ectopic calcification. Here, we aimed to show how CD14+ monocytes contribute to the pathophysiology of coexisting postmenopausal osteoporosis and carotid atherosclerosis.MethodsWe comprehensively analyzed osteoporosis data from the mRNA array dataset GSE56814 and the scRNA-seq dataset GSM4423510. Carotid atherosclerosis data were obtained from the GSE23746 mRNA dataset and GSM4705591 scRNA-seq dataset. First, osteoblast and vascular SMC lineages were annotated based on their functional expression using gene set enrichment analysis and AUCell scoring. Next, pseudotime analysis was applied to draw their differentiated trajectory and identify the key gene expression changes in crossroads. Then, ligandâreceptor interactions between CD14+ monocytes and osteoblast and vascular smooth muscle cell (SMC) lineages were annotated with iTALK. Finally, we selected calcification paradox-related expression in circulating monocytes with LASSO analysis.ResultsFirst, we found a large proportion of delayed premature osteoblasts in osteoporosis and osteogenic SMCs in atherosclerosis. Second, CD14+ monocytes interacted with the intermediate cells of the premature osteoblast and osteogenic SMC lineage by delivering TGFB1 and TNFSF10. This interaction served as a trigger activating the transcription factors (TF) SP1 and NFKB1 to upregulate the inflammatory response and cell senescence and led to a retarded premature state in the osteoblast lineage and osteogenic transition in the SMC lineage. Then, 76.49% of common monocyte markers were upregulated in the circulating monocytes between the two diseases, which were related to chemotaxis and inflammatory responses. Finally, we identified 7 calcification paradox-related genes on circulating monocytes, which were upregulated in aging cells and downregulated in DNA repair cells, indicating that the aging monocytes contributed to the development of the two diseases.ConclusionsOur work provides a perspective for understanding the triggering roles of CD14+ monocytes in the development of the calcification paradox in osteoporosis- and atherosclerosis-related cells based on combined scRNA and mRNA data. This study provided us with an elucidation of the mechanisms underlying the calcification paradox and could help in developing preventive and therapeutic strategies
Experimental investigation of pure aluminum sheets processed by constrained groove pressing
121-127Recently, a new severe plastic deformation
method named constrained groove pressing (CGP) has been invented for producing
ultra-fine grained sheet metals. Here, a multi-pass CGP is carried out on 1060
commercially pure aluminum sheets. Through a series of experimental research,
the evolutions of microstructure, tensile properties, forming load and surface
residual stress during the process are investigated. The grain size is greatly refined
from 29 ÎŒm of annealed samples to about 18 ÎŒm after pass four. Polygonized and dislocation-free
substructures of submicron level with well-defined boundaries is obtained. The ultimate
tensile strength and yield strength increase continuously until pass three and then
decrease by further deformation. Residual tensile stress is observed on the
surface of all pressed samples due to the unique stress-strain state, and it
increases dramatically during the first pass. The results show that lubrication
reduces the average residual tensile stress and its distribution homogeneity
along the longitudinal direction
Characterization of the Dynamic Imbibition Displacement Mechanism in Tight Sandstone Reservoirs Using the NMR Technique
An experimental technique is developed to investigate the dynamic imbibition displacement mechanism in tight sandstone formations of the Yanchang group of the Ordos basin. By combining the dynamic imbibition core flooding experiments and NMR technique, the effects of the injection volume and rate on displacement efficiency are investigated. Moreover, the displacement efficiency of dynamic imbibition is compared with that of static imbibition. This study gains insights into the micromechanisms of dynamic imbibition in tight sandstone formations. It is found that the relative displacement efficiency of dynamic imbibition increases with the increase of injection volume. But the increment amplitude decreases with the increase of injection volume. With the same injection volume, the core displacement efficiency of dynamic imbibition with high permeability is obviously improved. However, the core displacement efficiency decreases rapidly with the increase of injection volume. Optimal injection volumes are recommended for tight sandstone formations with different permeabilities. With the increase of the displacement rate, the core displacement efficiency of dynamic imbibition shows a trend of first rising and then declining. There exists an optimal displacement rate in dynamic imbibition displacement, and the optimal displacement rate almost linearly increases with the increase of core permeability. The static imbibition displacement efficiency increases with the increase of soaking time, but the increment amplitude slows down obviously. The displacement efficiency of static imbibition in small pores is higher than that of dynamic imbibition. The displacement efficiency of dynamic imbibition in large pores or microcracks is significantly higher than that of static imbibition. This study provides theoretical support for the optimization and improvement of the waterflooding recovery process in tight sandstone reservoirs.Peer Reviewe
Faeces As an Important Pollution Source of Airborne Pathogens in Traveling from Swine Farm
Airborne pathogens are the most important factor causing environmental issues on pig farms. Research on airborne swine-derived microbes has mainly concentrated on several specific microbes or pathogens. The present work was conducted to detect and identify the entire microbial community in piggery air and their dispersion by 16SrRNA sequencing. Fifteen faeces and eighty-four air samples were collected in swine barns and from different distances away from the barns, respectively. The results showed that the faeces and air share the most dominant bacteria. The top 10 genera belonged to Fimicutes, Proteobacteria and Bacteroidetes, and accounted for 54% and 76-84% of the total sequences. Moreover, great higher (P < 0.01) microbial diversity was detected in the faeces. This study indicated that a hygienic interval of 50 m should be set on swine farms to prevent the spreading infectious disease caused by airborne pathogens
Access to C(sp<sup>3</sup>)âC(sp<sup>2</sup>) and C(sp<sup>2</sup>)âC(sp<sup>2</sup>) Bond Formation via Sequential Intermolecular Carbopalladation of Multiple CarbonâCarbon Bonds
A synthetic strategy of 4-benzyl-substituted 1,3-butadiene
derivatives
through Pd-catalyzed three-component coupling reaction of benzyl chlorides,
alkynes, and monosubstituted alkenes is described. This tandem coupling
reaction forms a CÂ(sp<sup>3</sup>)âCÂ(sp<sup>2</sup>) bond and
a CÂ(sp<sup>2</sup>)âCÂ(sp<sup>2</sup>) bond sequentially in
a single-step operation
Standing wave performance test of IDT-SAW transducer prepared by silk-screen printing
With the advantages of high performance and low loss, interdigital surface acoustic wave (IDT-SAW) transducers are widely used in the fields of nondestructive testing, communication and broadcasting. The production, performance and application of surface acoustic wave (SAW) actuators has become a research hotspot. Based on the basic principle of SAW, an IDT-SAW transducer is designed and fabricated using silk-screen printing in this work. The experiment results show that in terms of SAW performance, the fabricated IDT-SAW transducer can generate standing wave fields comparable to those generated using traditional fabrication methods. The resonant frequency response of the IDT-SAW transducer and SAW attenuation coefficient were obtained by experiments. It has provided a method to test the transducer sensing performance by using fabricated IDT-SAW transducer