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Leukocytes and resident cells in the arterial wall contribute to atherosclerosis, especially at sites of disturbed blood flow. Expression of endothelial Tie1 receptor tyrosine kinase is enhanced at these sites, and attenuation of its expression reduces atherosclerotic burden and decreases inflammation. However, Tie2 tyrosine kinase function in atherosclerosis is unknown. Here we provide genetic evidence from humans and from an atherosclerotic mouse model to show that TIE2 is associated with protection from coronary artery disease. We show that deletion of Tie2 , or both Tie2 and Tie1 , in the arterial endothelium promotes atherosclerosis by increasing Foxo1 nuclear localization, endothelial adhesion molecule expression and accumulation of immune cells. We also show that Tie2 is expressed in a subset of aortic fibroblasts, and its silencing in these cells increases expression of inflammation-related genes. Our findings indicate that unlike Tie1, the Tie2 receptor functions as the dominant endothelial angiopoietin receptor that protects from atherosclerosis.

Coronary artery disease (CAD) is the leading cause of death worldwide. Recent meta-analyses of genome-wide association studies (GWAS) have identified over 175 loci associated with CAD. The majority of these loci are in non-coding regions and are predicted to regulate gene expression. Given that vascular smooth muscle cells (SMCs) play critical roles in the development and progression of CAD, we hypothesized that a subset of the CAD GWAS risk loci are associated with the regulation of transcription in distinct SMC phenotypes. Here, we measured gene expression in SMCs isolated from the ascending aortas of 151 ethnically diverse heart transplant donors in quiescent or proliferative conditions and calculated the association of their expression and splicing with ~6.3 million imputed single nucleotide polymorphism (SNP) markers across the genome. We identified 4,910 expression and 4,412 splice quantitative trait loci (sQTL) that represent regions of the genome associated with transcript abundance and splicing. 3,660 of the eQTLs had not been observed in the publicly available Genotype-Tissue Expression dataset. Further, 29 and 880 of the eQTLs were SMC- and sex-specific, respectively. To identify the effector transcript(s) regulated by CAD GWAS loci, we used four distinct colocalization approaches and identified 84 eQTL and 164 sQTLs that colocalized with CAD loci, highlighting the importance of genetic regulation of mRNA splicing as a molecular mechanism for CAD genetic risk. Notably, 20% and 35% of the eQTLs were unique to quiescent or proliferative SMCs, respectively. Two CAD loci colocalized with a SMC sex-specific eQTL (AL160313.1 and TERF2IP) and another locus colocalized with SMC-specific eQTL (ALKBH8). Also, 27% and 37% of the sQTLs were unique to quiescent or proliferative SMCs, respectively. The most significantly associated CAD locus, 9p21, was an sQTL for the long non-coding RNA CDKN2B-AS1, also known as ANRIL, in proliferative SMCs. Collectively, these results provide evidence for the molecular mechanisms of genetic susceptibility to CAD in distinct SMC phenotypes. Competing Interest Statement Johan Bjorkegren is a shareholder in Clinical Gene Network AB that has an invested interest in STARNET. The remaining authors have nothing to disclose. Footnotes * https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE193817 * https://virginia.box.com/s/t5e1tzlaqsf85z13o4ie2f9t1i0zfypd * https://virginia.box.com/s/o81cxrj5xne3xem4au785mupikduuwbu

In this research work, aluminum substituted Ni-Co ferrite nanoparticles have been produced by a simple and cost-effective method, i.e., sol–gel auto-combustion. Synthesized nanoparticles were annealed in a muffle furnace at 600°C for 3 h before characterization. The x-ray diffraction patterns revealed that the ferrite nanoparticles grew preferentially along the (311) plane and exhibit face centered cubic structure. The crystallite size of nanoparticles (14 to 17 nm) was estimated by Scherrer’s relation. The effect of aluminum substitution on structural parameters of ferrite nanoparticles, such as lattice constant and stacking faults, have been studied. Structural analysis revealed that the lattice constant of the nanoparticles decreases as a function of aluminum content. The Fourier transform infrared spectroscopy confirmed the spinal ferrite crystal structure of synthesized aluminum substituted Ni-Co ferrite nanoparticles. The surface morphology observed through scanning electron microscopy depicts the growth and distribution of nanograins with uniform size with in the samples. Dielectric properties investigated through impedance analyzer spectroscopy revealed that aluminum substituted Ni-Co ferrite nanoparticles demonstrated the high conductivity along with potential dielectric properties. These aluminum substituted Ni-Co ferrite nanoparticles would have possible applications in high storage memory and microwave devices.

Spinel ferrites have caught the attraction of researchers in the modern world. In this work, the spinel ferrites having formula Co 0.3 Cd 0.7 Zn 1.5 x Fe 2− x O 4 ( x  = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5) were prepared by Microemulsion method. Through XRD analysis, it was confirmed that all the samples were spinel ferrites. Crystallite size was found in the range of 9–17 nm, which was later on confirmed by SEM and EDX. Lattice parameter showed increasing trend which was due to larger ionic radii of Zn 2+ as compared to Fe 3+ . Impedance analyzer disclosed the electrical properties of prepared samples. Real and imaginary part of dielectric constant, impedance and modulus was determined with applied frequency range from 1 MHz to 3 GHz. The detailed electrical investigations were investigated in the frequency range of 100–3 GHz. Real and imaginary parts of impedance Z ′ and Z″ in the above frequency and substitution case suggested the existence of one relaxation regime which corresponds to grains which was totally different from its counterpart of bulks and has strong correlation with other ferrites. Real and imaginary part electrical modulus M ′ and M″ further showed the grains effect with increasing zinc substitution under the suppression of electrode polarization. A non-Debye relaxation behavior and the frequency-dependent conductivity were observed in dielectric spectra, which was also consistent with the results of AC conductivity spectra. Dielectric constant and dielectric loss showed a decreasing trend with increasing frequency and same was that with tangent loss. AC conductivity increased with increasing the frequency. Cole–Cole graph was plotted between M ′ and M ″ which confirmed the effect of only grains. Excellent dielectric properties suggest that these prepared nanoparticles are good for high-frequency device applications.

In this study, the sol-gel auto-combustion (SGAC) approach was used to synthesis praseodymium (Pr 3+ ) substituted Zinc-Cobalt (ZC) ferrites, having general formula Co 0.7 Zn 0.3 Pr x Fe 2−x O 4 (x = 0.0, 0.05, 0.10, 0.15, and 0.20). X-ray Diffraction (XRD) analysis revealed a secondary phase ( PrFeO 3 ) with a composition of x ≥ 0.10 and the presence of FCC structure. The crystallite size (D) of Pr 3+ doped ZC SFs decreased from 17.36 nm to 12.44 nm as the amount of Pr 3+ doping increased. Additionally, the lattice constant saw an enhancement from 8.34 a (Å) to 8.96 a (Å) with the incorporation of Pr 3+ into the ZC SFs. XRD and FTIR analysis verified the replacement of Pr 3+ into ZC SFs. Inhomogeneous grain size distribution was seen in samples by applying the Scanning Electron Microscopic (SEM) technique. It was discovered that the dielectric loss decreased with the applied frequency, which is helpful for high frequency device applications. The substitutions of Pr 3+ ions resulted in remanence (Mr (emu/g)), saturation magnetization (Ms (emu/g)) and coercivity (Hc (Oe)) maximum at x = 0.00 and minimum for x = 0.20 in ZC SFs, respectively. The maximum microwave frequency in GHz maximum for x = 0.00 (18.8 (GHz)) and minimum at sample x = 0.20 (7.86 (GHz)). According to the findings of our research, Pr 3+ substituted spinel ferrites appear to be very useful in radar, satellite communication, space communication, and microwave frequency applications.

A series of lanthanum (La)-doped nickel (Ni) ferrites NiLa x Fe 2- x O 4 with doping concentrations ( x  = 0.0, 0.01, 0.02, 0.03, 0.04, and 0.05) is synthesized via a sol–gel auto-combustion method. Structural properties are determined with the help of X-ray diffraction (XRD). The effect of La doping on dielectric properties of Ni ferrites is discussed. XRD analysis confirms the existence of pure FCC spinel phase, and no impurity phase was detected. The lattice constant decreases initially due to strain produced by La 3+ ions replacement. At higher doping concentrations, the lattice constant increases due to the large ionic radius of La 3+ as compared to Fe 3+ . Tangent loss (tan δ ), dielectric constant, and dielectric loss values are determined in the 1 MHz to 3 GHz frequency range, and explained by the Maxwell–Wagner model. A persistent behavior of dielectric loss and dielectric constant was found in the mid microwave frequency region. The most stable behavior of the dielectric constant ( ε ′) and dielectric loss ( ε″ ) in the high-frequency region is found with ( x  = 0.04). Ac conductivity is also discussed in the 1 MHz to 3 GHz region, and is found to be impacted by grain and grain boundary resistive behavior at low and high frequencies. Cole–Cole plots of different samples, corresponding to different doping concentrations, are used to describe the conduction phenomena. The stable response of dielectric constant ( ε ′) and dielectric loss ( ε″ ) in the mid microwave frequency region makes NiLa x Fe 2- x O 4 nanoparticles a potential candidate for microwave devices. Highlights Lanthanum-doped nickel ferrites nanoparticles were successfully synthesized by sol–gel auto-combustion method. The effect of lanthanum doping in nickel ferrites on structural and electrical properties was investigated. The structural parameters such as lattice constant, crystallite size, lattice strain, microstrain were determined. Frequency-dependent dielectric, impedance, and electric modulus properties were investigated in microwave region. Ac conductivity in microwave region was also investigated.

Dysprosium (Dy 3+ ) substituted cobalt-zinc spinel ferrites were synthesized having composition (Co 0.7 Zn 0.3 Dy 3+ xFe 2−x O 4 ) with the concentration ranges from (0.00, 0.5, 0.10, 0.15, and 0.20) by using the Sol–Gel synthesis. XRD analysis confirmed the FCC spinel structure of the prepared samples. Lattice constant and X-ray density were calculated in variance ranging from 8.40–8.46 Å and 5.28–5.77 g/cm 3 , respectively. Fourier Transformation Infrared Spectroscopy (FTIR) were used to measure the frequency band in between 411–562 cm −1 for the tetra and octahedral positions. Scanning electron microscopy was used to study the surface morphology of the prepared samples. The field emission transmission electron microscopy (FE-TEM) was used for the confirmation of particle size. The calculated value of crystalline size was 13 nm, while particle size was the best on 23 nm. It was observed that, on applied field frequency the dielectric parameters exhibits decreasing trend. Magnetic properties were examined by Vibrating Sample Magnetometer (VSM) method and found out saturation magnetization (63.99 emu/g), anisotropy (K) (5366.82 J/m 3 ) and magnetic moment (2.77) were in decreasing while retentivity (2.38 emu/g), squareness ratio (0.07) and coercivity H c (133.71Oe) were in increasing trend respectively. These features of Dy 3+ substituted Co–Zn spinel ferrites recommend their better use in sensors and high frequency devices.

Dysprosium (Dy 3+ )-substituted Ni–Co nanoparticles were synthesized by sol–gel technique. Structural and morphological analyses were accomplished by X-ray diffraction (XRD), scanning electron microscopy (SEM) and field emission transmission electron microscopy (FE-TEM). The crystallite size and lattice parameter followed a decreasing trend up on increase in Dy 3+ substitution for the concentration x  ≤ 0.15, which is due to the hindrance in crystallite growth and deposition of Dy 3+ on grain boundaries, respectively. The lattice strain was increased from 5.027 to 8.814 × 10 - 3 with enhancement in Dy 3+ content. The morphological studies showed uniform distribution of particles with slight agglomeration and the average particle size was calculated to be 22.17 nm, which is in good agreement with XRD results. The magnetic studies were executed by vibrating sample magnetometer (VSM) over a wide range of applied magnetic field. The soft ferrimagnetic nature of these ferrites was revealed by narrow (M–H) curve. The magnetic parameters exhibited decreasing behavior upon increasing amount of substitution. The coercivity ( H c ) was recorded to be 1097 Oe for x  = 0.00 and saturation magnetization ( M s ) was calculated in the range 27.04–40.86 emu/g. The anisotropy constant and magneton number were found to be in the range of 9887–46,703 erg/cm 3 and 1.21–1.71 µ B , respectively. These properties of prepared ferrites point towards their applicability in magnetic recording instruments, memory, and high-density data storage devices.

Praseodymium (III)-doped M-type SrPr x Fe 12-x O 19 (x = 0.00, 0.25, 0.50, 0.75, 1.00) hexa-ferrites were synthesized via micro-emulsion process followed by annealing of samples at 800 °C for 4 h. The effects of praseodymium particles on properties such as electrical, magnetic, and dielectric were studied. Via TGA the phase formation was observed to be started at 900 °C, and weight reduced to 5.27% at 1010 °C. Through X-ray diffraction (XRD), hexagonal structure was confirmed and structural properties were studied: the crystalline size, lattice constant, bulk and X-rays densities, i.e., 4.446 nm, 5.90 Å , 4.167 g·cm −3 and 6.46 g·cm −3 , respectively. The cation dispersion and shifting of frequencies were observed by FTIR at frequencies 430–590 cm −1 because of dopant of higher radii. Surface morphology, grain structure, and porosity were studied by scanning electron microscopy (SEM). Electrical properties were determined by impedance spectroscopy. The impact of Pr 3+ doping on distinct metrics, i.e. dielectric constants, dielectric loss, tan loss, A.C conductivity, was studied: 1.890, 0.023, 0.012, 0.001, respectively. The effects of Pr 3+ doping on retentivity, coercivity, saturation magnetization, and anisotropy were investigated by the vibrating sample magnetometer (VSM). The increase in saturation and remanence is due to the increase of Pr 3+ that retuned extra Fe 3+ ions from the lattice plot. The prepared materials offer valuable potential for applications of high-density recording medium applications and high-frequency devices.

Optomechanics, is the study of interactions between light and mechanical systems, has recently gained significant attention. This paper focuses on theoretical investigations of optomechanically induced transparency (OMIT) in a position-dependent hybrid optomechanical system. The optomechanical system contains N two-level atomic systems coupled to the cavity field. In addition to strong coupling fields, the cavity is driven by a weak probe laser field. The mass of the mechanical resonator is considered to be position-dependent, leading to nonlinear effects. Through analytical calculations and numerical simulations, we examined the dynamics and transmissivity of the system. Our findings highlighted the influence of the nonlinear parameter α , and coupling strengths on OMIT behaviors. Specifically, a significant dependence of the optical response on α was observed. Additionally, enhancing the coupling between the cavity field and the atomic system, while keeping α fixed, results in a wider and deeper transparency window. Our findings may have practical applications in the creation of highly efficient optical storage devices and quantum memory.