The development of small organic molecules with intense and switchable circularly polarized luminescence (CPL) is currently attracting great interest due to their promising applications in ...chiroptical devices and sensors. In this paper, CPL-active BF
2
-bridged azaanthracene dimers (
BA1
and
BA2
) were facilely synthesized by incorporating boron difluoride unit to the binaphthalene.
BA1
and
BA2
show moderate CPL in diluted solutions, however,
BA2
exhibited aggregation-amplified red CPL with large dissymmetry factor up to 1.6×10
−2
. Moreover, acid-/base-triggered CPL switch off/on were also realized via disaggregation/aggregation of
BA2
in tetrahydrofuran (THF)/water binary solvents.
The contact state of a seamless internal threaded copper tube and an aluminium foil fin not only affects the heat transfer efficiency of a tube-fin heat exchanger but also seriously affects its ...service life. In this study, hydraulic expansion technology was used to connect the copper tube with an internal thread with a 7 mm diameter to the fin of the heat exchanger. The influence of the expansion pressure and pressure holding time on the contact state was analysed through experiments and finite element simulation, and the variation law of the two on the contact state was obtained. The contact state was characterised by the contact gap and contact area. In order to obtain the specific contact area value, a new method of measuring the contact area was developed to reveal the variation in contact area between the copper tube and the fin after expansion. The results show that the contact gap decreases with an increase in expansion pressure, while the pressure holding time remains the same. The contact area increases with an increase in expansion pressure, and the rate of increase slows. When the expansion pressure is 18 MPa, the average contact gap is approximately 0.018 mm. When the expansion pressure reaches 16 MPa, the contact area ratio is 91.0%. When the expansion pressure increases to 18 MPa, the contact area ratio only increases by approximately 0.6%. Compared with the influence of the expansion pressure on the increase in contact area, the influence of the pressure holding time on the contact area is lower.
Immunodeficient mice reconstituted with human immune tissues and cells (humanized mice) are relevant and robust models for the study of HIV-1 infection, immunopathogenesis, and therapy. In this ...study, we performed a comprehensive comparison of human immune reconstitution and HIV-1 infection, immunopathogenesis and therapy between immunodeficient NOD/Rag2
/γ
(NRG) mice transplanted with human HSCs (NRG-hu HSC) and mice transplanted with HSCs and thymus fragments (NRG-hu Thy/HSC) from the same donors. We found that similar human lymphoid and myeloid lineages were reconstituted in NRG-hu HSC and NRG-hu Thy/HSC mice, with human T cells more predominantly reconstituted in NRG-hu Thy/HSC mice, while NRG-hu HSC mice supported more human B cells and myeloid cells reconstitution. HIV-1 replicated similarly and induced similar T cell depletion, immune activation, and dysfunction in NRG-hu HSC and NRG-hu Thy/HSC mice. Moreover, combined antiretroviral therapy (cART) inhibited HIV-1 replication efficiently with similar persistent HIV-1 reservoirs in both models. Finally, we found that blocking type-I interferon signaling under cART treatment transiently activated HIV-1 reservoirs, enhanced T cell recovery and reduced HIV-1 reservoirs in both HIV-1 infected NRG-hu HSC and NRG-hu Thy/HSC mice. In summary, we report that NRG-hu Thy/HSC and NRG-hu HSC mice support similar HIV-1 infection and similar HIV-1 immunopathology; and HIV-1 replication responds similarly to cART and IFNAR blockade therapies. The NRG-hu HSC mouse model reconstituted with human HSC only is sufficient for the study of HIV-1 infection, pathogenesis, and therapy.
Sand flux is the key factor to determine the migration of sand dunes and the erosion to the surrounding environment. There are crescent-shaped sand dunes of various scales in the desert, and there ...are significant differences in spatial wind field and sand flux among them. However, due to the difficulty of monitoring, it is difficult to continuously observe the spatial wind field and sand flux around the larger crescentic dunes. On the basis of the Reynolds-Average Navier-Stokes (RA-NS) equation and the stress and sand flux model, the distribution of wind field and sand flux of a circular dune with a height of 4.2 m and a length of about 100 m during the four evolutionary periods of the evolution into a crescentic dune was simulated in this study. By comparing with the measured results, we verified that the closer to the leeward side, the more the simulated values of the velocity in wind field and sand flux were in line with the measured results. In order to further analyze the influence of the height of dune and other relevant parameters on sand flux, we simulated the influence on wind field and sand flux by changing the air viscosity and wind velocity of upper boundary. We found that the air viscosity mainly affected the amount of deposited sand on the leeward side of sand dune, while the increase of wind velocity would undoubtedly increase the sand flux of the whole sand dune. In addition, the simulation results also showed that the influence of changes in height of dune on the turbulent intensity of leeward side was very significant, and the turbulent intensity increased with the height of dune. The height changes of tall dunes gradually affected the transport of sand caused by wind flow behind the leeward side because that the rotation of the wind flow would form new vortexes at the large pores behind the leeward side, which would increase the turbulent energy in space and thus would increase the distance of migration of the lifting sand. While the low sand dunes could not form extra small vortexes at the bottom of the leeward side, so the wind velocity was small and the eddy currents behind the leeward side were more stable. The simulation results indicated that wind velocity was not the only reason for increasing the amount of sand flux, and the fluctuation of wind flow caused by turbulence could also stimulate the movement of sand particles on the ground.
The assembled camshaft is a novel manufacturing product which connects the cam and the mandrel by tube hydroforming (THF) technology after they are processed separately. However, in the process of ...THF, the structure of the cam-bores has a crucial influence on the connection strength of the assembled camshafts. Therefore, three kinds of cam-bores with circular structure, isometric-trilateral profile and logarithmic spiral profile are selected for hydroforming with a hollow mandrel (tube) in this study. The finite-element-analysis is carried out by ABAQUS software, the variations of (residual) contact pressure and contact area under different structures are obtained, and the torsional angle variations after assembly are measured. Further, the connection strength of the assembled camshaft under three structures is discussed. The results show that the evaluation of connection strength of the assembled camshaft is affected by many factors, including contact pressure, maximum residual contact pressure, axial and circular residual contact pressure, contact area and its rate, residual contact area percentage and torsional angle. Through the comprehensive analysis of various factors, the torsional angle of the camshaft with circular structure is the largest, i.e. poor connection strength. By contrast, the torsional strength of the camshaft with isometric-trilateral profile is the largest, namely, the best connection strength.
Infantile Malignant Osteopetrosis (IMO) is a rare, severe autosomal recessive form of osteopetrosis. Here, the peripheral blood mononuclear cells (PBMCs) extracted from a patient with IMO carrying a ...compound heterozygous mutation in T cell immune regulator 1, ATPase H + transporting V0 subunit a3 (TCIRG1) gene (c.242delC; c.1114C > T) were successfully reprogrammed using Sendai virus encoding the four Yamanaka factors. The generated hiPSCs, IMO-hiPSCs, displayed typical embryonic stem cell-like morphology and were verified by expression of pluripotency markers such as OCT4, SOX2, NANOG, TRA-1–60 and SSEA4, as well as in vivo and in vitro differentiation into derivatives of three germ layers.
This study aimed to examine the validity and reliability of the Chinese version of the Involuntary Musical Imagery Scale and its application in mainland China. Two studies were conducted. In Study 1, ...the Involuntary Musical Imagery Scale contents were translated into Chinese and semi-structured interviews were conducted with 10 undergraduate students; on this basis, a preliminary version of the Chinese Involuntary Musical Imagery Scale was generated. Subsequently, the psychometric properties of the Chinese Involuntary Musical Imagery Scale were analyzed based on 443 questionnaires; a four-factor model was found to achieve the best fit to the collected data and the Chinese Involuntary Musical Imagery Scale showed excellent internal consistency. In Study 2, the Chinese Involuntary Musical Imagery Scale was used to investigate the experience of involuntary musical imagery in mainland China (n = 426), where we explored the correlations among its factors and mental control, obsessive-compulsive traits, neuroticism, and openness; the results suggest that the frequency of involuntary musical imagery in Chinese individuals was lower than that of individuals in Western samples, and there were significant correlations between characteristics of involuntary musical imagery and various individual traits. Additionally, differences in involuntary musical imagery between students from urban areas and those from rural areas, as well as between only-child students and students with siblings, were found for the first time.
Tigecycline serves as one of the last-resort antibiotics to treat severe infections caused by carbapenem-resistant Enterobacterales. Recently, a novel plasmid-mediated resistance-nodulation-division ...(RND)-type efflux pump gene cluster,
, and its variants,
and
, encoding tetracyclines and tigecycline resistance, were revealed. In this study, we reported three
-harboring
species strains, collected from two teaching tertiary hospitals in China, including one
, one
, and one
. The three strains were characterized by antimicrobial susceptibility testing (AST), conjugation assay, WGS, and bioinformatics analysis. AST showed that
and
strains were resistant to tigecycline with MIC values of 4μg/ml, whereas the
was susceptible to tigecycline with an MIC value of 1μg/ml. The
clusters were located on three similar IncHI1B plasmids, of which two co-harbored the metallo-β-lactamase gene
. Conjugation experiments showed that all three plasmids were capable of self-transfer
conjugation. Our results showed, for the first time, that this novel plasmid-mediated tigecycline resistance mechanism
has spread into different
species, and clinical susceptibility testing may fail to detect. The co-occurrence of
and
in the same plasmid is of particular public health concern as the convergence of "mosaic" plasmids can confer both tigecycline and carbapenem resistance. Its further spread into other clinical high-risk
clones will likely exacerbate the antimicrobial resistance crisis. A close monitoring of the dissemination of
encoding resistance should be considered.
This study used a bidirectional 2-sample Mendelian randomization study to investigate the potential causal links between mtDNA copy number and cardiometabolic disease (obesity, hypertension, ...hyperlipidaemia, type 2 diabetes T2DM, coronary artery disease CAD, stroke, ischemic stroke, and heart failure).
Genetic associations with mtDNA copy number were obtained from a genome-wide association study (GWAS) summary statistics from the UK biobank (n = 395,718) and cardio-metabolic disease were from largest available GWAS summary statistics. Inverse variance weighting (IVW) was conducted, with weighted median, MR-Egger, and MR-PRESSO as sensitivity analyses. We repeated this in the opposite direction using instruments for cardio-metabolic disease.
Genetically predicted mtDNA copy number was not associated with risk of obesity (P = 0.148), hypertension (P = 0.515), dyslipidemia (P = 0.684), T2DM (P = 0.631), CAD (P = 0.199), stroke (P = 0.314), ischemic stroke (P = 0.633), and heart failure (P = 0.708). Regarding the reverse directions, we only found that genetically predicted dyslipidemia was associated with decreased levels of mtDNA copy number in the IVW analysis (β= - 0.060, 95% CI - 0.044 to - 0.076; P = 2.416e-14) and there was suggestive of evidence for a potential causal association between CAD and mtDNA copy number (β= - 0.021, 95% CI - 0.003 to - 0.039; P = 0.025). Sensitivity and replication analyses showed the stable findings.
Findings of this Mendelian randomization study did not support a causal effect of mtDNA copy number in the development of cardiometabolic disease, but found dyslipidemia and CAD can lead to reduced mtDNA copy number. These findings have implications for mtDNA copy number as a biomarker of dyslipidemia and CAD in clinical practice.
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