Search

We report thermopower and electrical resistance of valence-unstable CeNi 4 Cu and its non-magnetic analogue LaNi 4 Cu in the range of temperatures between 4 and 900 K. Based on experimental data we analyze the contributions of cerium f -states to the total thermopower, considering electronic transport properties of the crystal matrix in which the f -electron subsystem is located. We demonstrate that CeNi 4 Cu is a concentrated Kondo system with high Kondo temperature, Т К , of approximately 1300 K, where temperature behavior of thermoelectric power manifests combined effects of Kondo scattering on localized f -centers together with scattering associated with the presence of a narrow d -band near the Fermi level. We further discuss the features of the temperature stability of the position of the narrow peak (so-called Kondo resonance) in the density of states at the Fermi level. • CeNi 4 Cu is a concentrated Kondo system with high Kondo temperature, Т К ≈1300 K. • Peculiarities of thermopower behavior are due to the combined effect of spin fluctuations in Ce- and Ni-sublattices. • Thermoelectric power of CeNi4Cu in a wide range of temperatures is well described in the two-band model. • Detected temperature instability of the position Kondo resonance at the Fermi level at temperatures T > 300 K. [ABSTRACT FROM AUTHOR]

We have obtained X-ray emission spectra of Ga and Ge in Ca3Ga2Ge4O14, X-ray emission OKα-spectra in Ca3Ga2Ge4O14, Ca3Ga2Ge4O14 + Ce3%, and Ca3Ga2Ge4O14 + Eu4% and Xray photoelectron spectra in Ca3Ga2Ge4O14 . Our X-ray spectral studies of the Ca3Ga2Ge4O14 gallogermanate have shown that the top of the valence band near the Fermi level is formed mainly by p states of gallium and germanium as well as p states of oxygen, whose intensity is sufficiently low. The middle of the valence band is formed by gallium 3d states with oxygen 2s states lying below them. These states are hybridized with 4p states of gallium and germanium because of which there are Kβ′′-satellites in the Kβ2-subbands of gallium and germanium. The bottom of the valence band is formed by 3d states of germanium, whose contribution to chemical bonding is insignificant. The X-ray emission bands of Ga and Ge in Ca3Ga2Ge4O14 and the photoelectron spectrum of the valence electrons of Ca3Ga2Ge4O14 are in good agreement. The OKα-band changes its fine structure only slightly upon doping Ca3Ga2Ge4O14 with Ce or Eu. The investigations of intrinsic luminescence under X-rays excitation of Ca3Ga2Ge4O14 gallogermanate are presented. [ABSTRACT FROM AUTHOR]

Deep dyspareunia affects 50% of women with endometriosis and has significant negative effects on relationships and sexual function. Previous research has identified painful bladder syndrome as a significant contributor to deep dyspareunia which suggests factors such as central sensitization that may contribute to the etiology of deep dyspareunia. In women with endometriosis, those with high severity of deep dyspareunia and painful bladder syndrome had greater central sensitization as measured by a self-reported questionnaire. [Extracted from the article]

The band structure of Ca 3 Ga 2 Ge 3 О 12 with the garnet structure has been determined for the first time by X-ray emission and photoelectron spectroscopy. It has been established that the bottom of the valence band is formed by Ge d states, which are not dominant in the chemical bonding. Strong hybridization of oxygen 2 s states with 4 p states of Ga and Ge revealed by the presence of an extra structure in the X-ray emission spectra has been found. The middle of the valence band has been demonstrated to be occupied by d states of Ga, while Ga and Ge 4 р states with a considerable admixture of oxygen 2 p states form the top of the valence band. [ABSTRACT FROM AUTHOR]

Ternary intermetallic R5Fe6Sn18 (R = Tm, Lu) compounds have been synthesized from the elements by arc melting, annealed at 670 K and characterized by X-ray powder diffraction and energy dispersive X-ray analyses. Performed structure refinements have shown that they crystallize in the cubic Tb5Rh6Sn18 structure type (space group Fm-3m, a = 13:55399(4) Å, a = 133.53243(5) Å for Tm and Lu compounds, respectively). Using 57Fe Mössbauer spectroscopy it has been found that the magnetic state of the Fe atoms in the Tm5Fe6Sn18 and Lu5Fe6Sn18 stannides is paramagnetic. The value of the isomer shifts for Lu5Fe6Sn18 and Tm5Fe6Sn18 is positive relative to pure Fe. The 57Fe Mössbauer spectra for Lu5Fe6Sn18 and Tm5Fe6Sn18 stannides have shown that the quadrupole splitting for the Fe position (24e) have magnitudes of 0.43 and 0.45 mm/s, respectively. The similarity of these values is consistent with a qualitative crystal structure analysis. The examined Tm5Fe6Sn18 and Lu5Fe6Sn18 compounds have been found to be characterized by metallic-like conductivity and high values of electrical resistivity (672.9 μΩ cm, 623.8 μΩ cm at 300 K for Tm and Lu, respectively). [ABSTRACT FROM AUTHOR]

The valence band electronic structure of HfFe2Si2 has been established for the first time based on X-ray emission spectroscopy measurements. The band structure and X-ray emission spectra have been also obtained theoretically using the ab initio LMTO method in the non-relativistic approximation. The electron configuration of Si in the compound HfFe2Si2 can be described as s1.1p1.5. The theoretical and experimental results are in satisfactory agreement. [ABSTRACT FROM AUTHOR]

Study Question: Does incisional endometriosis (IE) harbor somatic cancer-driver mutations?Summary Answer: We found that approximately one-quarter of IE cases harbor somatic-cancer mutations, which commonly affect components of the MAPK/RAS or PI3K-Akt-mTor signaling pathways.What Is Known Already: Despite the classification of endometriosis as a benign gynecological disease, it shares key features with cancers such as resistance to apoptosis and stimulation of angiogenesis and is well-established as the precursor of clear cell and endometrioid ovarian carcinomas. Our group has recently shown that deep infiltrating endometriosis (DE), a form of endometriosis that rarely undergoes malignant transformation, harbors recurrent somatic mutations.Study Design, Size, Duration: In a retrospective study comparing iatrogenically induced and endogenously occurring forms of endometriosis unlikely to progress to cancer, we examined endometriosis specimens from 40 women with IE and 36 women with DE. Specimens were collected between 2004 and 2017 from five hospital sites in either Canada, Germany or the Netherlands. IE and DE cohorts were age-matched and all women presented with histologically typical endometriosis without known history of malignancy.Participants/materials, Setting, Methods: Archival tissue specimens containing endometriotic lesions were macrodissected and/or laser-capture microdissected to enrich endometriotic stroma and epithelium and a hypersensitive cancer hotspot sequencing panel was used to assess for presence of somatic mutations. Mutations were subsequently validated using droplet digital PCR. PTEN and ARID1A immunohistochemistry (IHC) were performed as surrogates for somatic events resulting in functional loss of respective proteins.Main Results and the Role Of Chance: Overall, we detected somatic cancer-driver events in 11 of 40 (27.5%) IE cases and 13 of 36 (36.1%) DE cases, including hotspot mutations in KRAS, ERBB2, PIK3CA and CTNNB1. Heterogeneous PTEN loss occurred at similar rates in IE and DE (7/40 vs 5/36, respectively), whereas ARID1A loss only occurred in a single case of DE. While rates of detectable somatic cancer-driver events between IE and DE are not statistically significant (P > 0.05), KRAS activating mutations were more prevalent in DE.Limitations, Reasons For Caution: Detection of somatic cancer-driver events were limited to hotspots analyzed in our panel-based sequencing assay and loss of protein expression by IHC from archival tissue. Whole genome or exome sequencing, or epigenetic analysis may uncover additional somatic alterations. Moreover, because of the descriptive nature of this study, the functional roles of identified mutations within the context of endometriosis remain unclear and causality cannot be established.Wider Implications Of the Findings: The alterations we report may be important in driving the growth and survival of endometriosis in ectopic regions of the body. Given the frequency of mutation in surgically displaced endometrium (IE), examination of similar somatic events in eutopic endometrium, as well as clinically annotated cases of other forms of endometriosis, in particular endometriomas that are most commonly linked to malignancy, is warranted.Study Funding/competing Interest(s): This study was funded by a Canadian Cancer Society Impact Grant [701603, PI Huntsman], Canadian Institutes of Health Research Transitional Open Operating Grant [MOP-142273, PI Yong], the Canadian Institutes of Health Research Foundation Grant [FDN-154290, PI Huntsman], the Canadian Institutes of Health Research Project Grant [PJT-156084, PIs Yong and Anglesio], and the Janet D. Cottrelle Foundation through the BC Cancer Foundation [PI Huntsman]. D.G. Huntsman is a co-founder and shareholder of Contextual Genomics Inc., a for profit company that provides clinical reporting to assist in cancer patient treatment. R. Aguirre-Hernandez, J. Khattra and L.M. Prentice have a patent MOLECULAR QUALITY ASSURANCE METHODS FOR USE IN SEQUENCING pending and are current (or former) employees of Contextual Genomics Inc. The remaining authors have no competing interests to declare.Trial Registration Number: Not applicable. [ABSTRACT FROM AUTHOR]

X-ray absorption spectrum at the Yb L 3 edge and X-ray emission spectra of Ni and P at the K and L 2,3 edges have been studied experimentally and theoretically in the mixed valent compound YbNi 2 P 2 with ThCr 2 Si 2 type crystal structure. The electronic structure of YbNi 2 P 2 is investigated using the fully relativistic Dirac linear muffin-tin orbital (LMTO) band-structure method. The effect of the spin–orbit (SO) interaction and Coulomb repulsion U on the electronic structure of YbNi 2 P 2 is examined in the frame of the LSDA + SO + U method. The core-hole effect in the final states as well as the effect of the electric quadrupole E 2 transitions have been investigated. A good agreement between the theory and the experiment was found. Both the trivalent and the divalent Yb ions in YbNi 2 P 2 are reflected in the experimentally measured Yb L 3 X-ray absorption spectrum simultaneously. We found that the best agreement between the experimental spectrum and sum of the theoretically calculated Yb 2+ and Yb 3+ spectra is achieved with 73% ytterbium ions in 2+ state and 27% ions in 3+ state. [ABSTRACT FROM AUTHOR]

In this study the comparison of dielectric behaviour of BaTi1-xZrxO3(BTZx) ceramic samples prepared by means of a solid state and mechanochemical synthesis was presented. A single phase of perovskite structure was identified in the samples at room temperature. No significant impurities were detected in an EDS spectrum and the samples had a good stoichiometric ratio. The morphology of the investigated samples was characterized by a scanning electron microscopy (SEM). The investigation of dielectric properties of the BTZx samples within the temperature range from 140 K to 600 K was performed by means of a dielectric spectroscopy method at the frequency ranging from 0.1 Hz to 10 MHz. The temperature dependences of real part of dielectric permittivity showed the changes of the character of the paraelectric–ferroelectric (PE–FE) phase transition for the ceramic samples obtained by means of both methods. [ABSTRACT FROM PUBLISHER]