Magnetic anisotropy in van-der-Waals ferromagnet VI3

A comprehensive study of magnetocrystalline anisotropy of a layered van-der-Waals ferromagnet VI3 was performed. We measured angular dependences of the torque and magnetization with respect to the direction of the applied magnetic field within the "ac" plane perpendicular to and within the basal ab plane, respectively. A two-fold butterfly-like signal was detected by magnetization in the perpendicular "ac" plane. This signal symmetry remains conserved throughout all magnetic regimes as well as through the known structural transition down to the lowest temperatures. The maximum of the magnetization signal and the resulting magnetization easy axis is significantly tilted from the principal c axis by ~40{\deg}. The close relation of the magnetocrystalline anisotropy to the crystal structure was documented. In contrast, a two-fold-like angular signal was detected in the paramagnetic region within the ab plane in the monoclinic phase, which transforms into a six-fold-like signal below the Curie temperature TC. With further cooling, another six-fold-like signal with an angular shift of ~30{\deg} grows approaching TFM. Below TFM, in the triclinic phase, the original six-fold-like signal vanishes, being replaced by a secondary six-fold-like signal with an angular shift of ~30{\deg}.Comment: 14 pages, 10 figure

Identification of a Specific Vimentin Isoform That Induces an Antibody Response in Pancreatic Cancer

Pancreatic cancer has a poor prognosis, in part due to lack of early detection. The identification of circulating tumor antigens or their related autoantibodies provides a means for early cancer diagnosis. We have used a proteomic approach to identify proteins that commonly induce a humoral response in pancreatic cancer. Proteins from a pancreatic adenocarcinoma cell line (Panc-1) were subjected to two-dimensional PAGE, followed by Western blot analysis in which individual sera were tested for autoantibodies. Sera from 36 newly diagnosed patients with pancreatic cancer, 18 patients with chronic pancreatitis and 15 healthy subjects were analyzed. Autoantibodies were detected against a protein identified by mass spectrometry as vimentin, in sera from 16/36 patients with pancreatic cancer (44.4%). Only one of 18 chronic pancreatitis patients and none of the healthy controls exhibited reactivity against this vimentin isoform. Interestingly, none of several other isoforms of vimentin detectable in 2-D gels exhibited reactivity with patient sera. Vimentin protein expression levels were investigated by comparing the integrated intensity of spots visualized in 2-D PAGE gels of various cancers. Pancreatic tumor tissues showed greater than a 3-fold higher expression of total vimentin protein than did the lung, colon, and ovarian tumors that were analyzed. The specific antigenic isoform was found at 5–10 fold higher levels. The detection of autoantibodies to this specific isoform of vimentin may have utility for the early diagnosis of pancreatic cancer

Extremely low frequency magnetic fields emitted by cell phones

Cell phones expose significant parts of the human brain and head to extremely low frequency (ELF) magnetic fields (MF) classified by the IARC as a 2B carcinogen. ELF MF was measured on the front and back sides of 15 cell phones in standby, speaking, and listening modes for 2G and 3G standards in two frequency bands, LF1: 5 Hz–200 Hz and LF2: 120 Hz—10 kHz. The highest MF value was 70.03 µT (RMS) in LF1 (2G, listening mode, front side) and 12.67 µT (RMS) in LF2 (2G, speaking mode, front side). The 3G cell phones consistently emitted a lower ELF MF compared to the 2G ones. The exposure to ELF MF was also simulated at various locations (head, thorax, pelvis) using the CST Studio Suite. The simulations revealed 8.45 µT, 7.5 µT, and 6.09 µT in the middle of the head (midbrain), 3.89 µT, 3.98 µT, and 2.83 µT for the middle of the thorax (heart), and 2.03 µT, 1.96 µT, and 1.56 µT in the middle of the pelvis (scrotum) for 10 Hz, 50 Hz, and 200 Hz, respectively. These values are comparable to those reported to induce biological and health effects, including those related to carcinogenesis. The results can be used in future studies concerning the ELF exposure or the combined effects of electromagnetic fields of radiofrequency and ELF

Magnetic Properties and Mossbauer spectroscopy of NdFe(1-x)MnxO(3)

The effect of particle reduction to nanoscale size and substitution of Mn3+ ions for Fe3+ ions on the crystal structure, lattice dynamics, Mossbauer spectra and magnetic properties in NdFe(1-x)MnxO(3) compounds have been studied. X-ray powder diffraction and Raman spectroscopy revealed that the Jahn-Teller distortion of lattice dominates for samples with x GT 0.4. The average particle size of NdFeO3 nanoparticles (NAP) increases with annealing at 600 degrees C from about 15 nm to 25 nm. The presence of superparamagnetic particles was indicated by Mossbauer measurements in NdFeO3 NAP system. Sextets in NdFe(1-x)MnxO(3) Mssbauer spectra can be modelled with several local environments of Fe3+ induced by substitution. The reduction of dimensionality and the substitution induce a decrease of the Neel temperature T-Nl from 691 K to 544 K for NAP or to 356 K for x = 0.4, however the temperature of spin reorientation T-SR increases with substitution. The saturated magnetization obtained at 1.9 K increases and ferromagnetic component is removed below T-SR with the substitution.International Conference on Strongly Correlated Electron Systems (SCES), Jul 07-14, 2014, Univ Grenoble, Grenoble, Franc

Potentials of Plasma NGAL and MIC-1 as Biomarker(s) in the Diagnosis of Lethal Pancreatic Cancer

Pancreatic cancer (PC) is lethal malignancy with very high mortality rate. Absence of sensitive and specific marker(s) is one of the major factors for poor prognosis of PC patients. In pilot studies using small set of patients, secreted acute phase proteins neutrophil gelatinase associated lipocalin (NGAL) and TGF-β family member macrophage inhibitory cytokine-1 (MIC-1) are proposed as most potential biomarkers specifically elevated in the blood of PC patients. However, their performance as diagnostic markers for PC, particularly in pre-treatment patients, remains unknown. In order to evaluate the diagnostic efficacy of NGAL and MIC-1, their levels were measured in plasma samples from patients with pre-treatment PC patients (n = 91) and compared it with those in healthy control (HC) individuals (n = 24) and patients with chronic pancreatitis (CP, n = 23). The diagnostic performance of these two proteins was further compared with that of CA19-9, a tumor marker commonly used to follow PC progression. The levels of all three biomarkers were significantly higher in PC compared to HCs. The mean (± standard deviation, SD) plasma NGAL, CA19-9 and MIC-1 levels in PC patients was 111.1 ng/mL (2.2), 219.2 U/mL (7.8) and 4.5 ng/mL (4.1), respectively. In comparing resectable PC to healthy patients, all three biomarkers were found to have comparable sensitivities (between 64%-81%) but CA19-9 and NGAL had a higher specificity (92% and 88%, respectively). For distinguishing resectable PC from CP patients, CA19-9 and MIC-1 were most specific (74% and 78% respectively). CA19-9 at an optimal cut-off of 54.1 U/ml is highly specific in differentiating resectable (stage 1/2) pancreatic cancer patients from controls in comparison to its clinical cut-off (37.1 U/ml). Notably, the addition of MIC-1 to CA19-9 significantly improved the ability to distinguish resectable PC cases from CP (p = 0.029). Overall, MIC-1 in combination with CA19-9 improved the diagnostic accuracy of differentiating PC from CP and HCs

Gene expression profiling of breast cancer in Lebanese women

MPP grants MPP320046 and MPP320061