Introduction: Currently, very few studies are available concerning the ă mammalian Hippo pathway in bone sarcomas. YAP/TAZ transcription ă co-activators are key downstream effectors of this pathway ...and may also ă have oncogenic properties. Additionally, recent in-vitro experiments ă showed that expression of beta 1-integrin promoted metastasis in ă osteosarcomas. This study investigated the expression of YAP/TAZ and ă beta 1-integrin in human osteosarcomas. Materials and methods: We performed automated immunohistochemistry on ă tissue-microarrays (TMA) in which 69 conventional osteosarcomas biopsies ă performed prior to chemotherapy were embedded. Cellular localization and ă semi-quantitative analysis of each immunostain was performed using ă Immunoreactive Score (IRS) and correlated to clinico-pathological data.Results: Cytoplasmic expression of beta 1-integrin was noted in 54/59 ă osteosarcomas (92%), with 33/59 cases (56%) displaying membranous ă staining. YAP/TAZ was expressed in 27/45 osteosarcomas (60%), with 14 ă cases (31%) showing cytoplasmic expression while 13 other cases (28%) ă displayed nuclear expression. No link was found between YAP/TAZ or beta ă 1-integrin expression and response to chemotherapy. In univariate ă analysis, YAP/TAZ immunoreactive score was pejoratively correlated with ă overall survival (p = 0.01). Expression of beta 1-integrin on cell ă membrane was also pejorative for OS (p = 0.045). In multivariate ă analysis, YAP/TAZ nuclear expression was an independent prognostic ă factor for PFS (p = 0.035).Conclusion: this study indicates that beta 1-integrin and YAP/TAZ ă proteins are linked to prognosis and therefore could be therapeutic ă targets in conventional osteosarcomas.
This study presents the performance of a magneto-dielectric material (MDM) specially developed to enable the tunability of antenna devices operating in the VHF band. The magnetic susceptibility ...variation of the MDM material is controlled by a current flowing through the sample which creates a DC magnetic field inside the sample with the same symmetry as the magnetic domains. By changing the magnetization state of the MDM with a low DC magnetic field of 740 A/m, a tunability of 40% can be observed. The MDM tunability at VHF frequencies is also verified by microwave measurements for different magnetization states.
This study deals with the noteworthy effects of inner demagnetizing effects on the ferrimagnetic resonance (FMR) of disordered heterostructures, in particular, close to their percolation ...concentration (
C
p) in magnetic material. A recognized experimental fact is that the FMR increases with decreasing soft ferrite content in such composite materials. We have undertaken a systematic experimental study of Ni
1−
x
Zn
x
Fe
2O
4 composite materials, at the low frequency range and at their gyroresonance. Our interpretation of the data, based on the Effective Medium Theory, uses a reciprocity principle developed for heterostrucures. At concentrations below
C
p magnetic gaps, which originate from the magnetic dilution, may cause a cut-off of the magnetic flux-paths in the composite medium, leading to inner demagnetizing effects that increase the magnetic anisotropy. Whereas above
C
p, the topology of the percolating cluster allows a magnetic flux path to be continuous throughout the material, here the inner demagnetizing effects vanish, leading the FMR to be that of the bulk itself in the concentration range going from
C
p to unity.
A self-biased Ku-band circulator has been designed and measured. A pre-oriented substituted strontium hexaferrite SrM with a strong anisotropy field and high remanent magnetization was used for the ...component design. A minimum insertion loss of 0.95 dB with more than 15 dB isolation has been measured. However, a frequency shift of 1.5 GHz has been observed between the simulation and the measurement. Retro-simulations, taking into account the metallization dimensions, led us to believe the anisotropy field and the permittivity considered to be inaccurately evaluated. Nonetheless, these experimental results demonstrate the high potential of hexaferrites for the realization of Ku-band circulators.
In this study, tungsten substituted Ni-Zn nano ferrites of the composition Ni
0.5
Zn
0.5
W
x
Fe
2−x
O
4
with x = 0.0, 0.2, 0.4 have been synthesized by a co-precipitation method. The prepared samples ...were pre-sintered at 850 °C and then annealed at 1000 °C for 3 h each. The structural, morphological, optical and magnetic properties of these samples were studied by using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy (RS) and Mössbauer spectroscopy (MS). XRD revealed the formation of spinel single-phase structure with an average crystallite size of 53–60 nm. Fourier transform infrared spectroscopy show two prominent peaks primarily due to the tetrahedral and octahedral stretching vibrations in the range of 400–600 cm
−1
. Raman spectra indicate first order three Raman active modes; (A1 g + Eg + T2 g) at around 688, 475 and 326 cm
−1
. Mössbauer spectroscopy reveals that substitution of W
3+
for Fe
3+
cation results in reduction of total magnetic moment and consequently the net magnetization.
Magneto-Dielectric Material is used for the design of an electrically small monopole antenna at the VHF band. By loading partially with MDM along with metallic parasitic element and impedance ...matching of non-resonant (Small) Monopole, the proposed antenna achieves a miniaturization rate factor of the height greater than 70%, a satisfactory gain for this size and 10% of impedance bandwidth are obtained.
Tungsten substituted nickel-zinc ferrite nanoparticles with chemical composition of Ni0.5Zn0.5WxFe2-xO4 (x = 0.0, 0.2, 0.4, 0.6, 0.8 & 1.0) were successfully synthesized by a chemical ...co-precipitation method. The prepared ferrites were pre sintered at 850 °C and then annealed at 1000 °C in a muffle furnace for 3 h each. This sintered powder was inspected by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM) to study the structural, optical, and magnetic properties. XRD measurement revealed the phase purity of all the nanoferrite samples with cubic spinel structure. The estimated crystallite size by X-ray line broadening is found in the range of 49–62 nm. FTIR spectra of all the samples have observed two prominent absorption bands in the range 400–700 cm−1 arising due to tetrahedral and octahedral stretching vibrations. Vibrating sample magnetometer experiments showed that the saturation magnetizations (MS) decreased with an increase in non-magnetic tungsten ion doping. The electrical resistivity of tungsten doped NiZn nano ferrites were examined extensively as a function of temperature. With an increase in tungsten composition, resistivity was found to decrease from 2.2 × 105 Ω cm to 1.9 × 105 Ω cm which indicates the semiconducting behavior of the ferrite samples. The activation energy also decreased from 0.0264 to 0.0221 eV at x = 0.0 to x = 1.0. These low coercive field tungsten doped NiZn ferrites are suitable for hyperthermia and sensor applications. These observations are explained in detail on the basis of various models and theories.
•Cubic spinel structure with crystallite size 62–49 nm.•FTIR showed two main absorption bands due to tetrahedral and octahedral vibrations.•Saturation magnetization and retentivity increases to x = 0.2 and then decreases.•Resistivity and activation energy showed decreasing trend with W3+ ion doping.
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