Analysis of tissue surrounding thyroid nodules by ultrasound digital images

Since US is not easily reproducible, the digital image analysis (IA) has been proposed so that the image evaluation is not subjective. In fact, IA meets the criteria of objectivity, accurateness, and reproducibility by a matrix of pixels whose value is displayed in a gray level. This study aims at evaluating via IA the tissue surrounding a thyroid nodule (backyard tissue, BT) from goitres with benign (b-BT) and malignant (m-BT) lesions. Sixty-nine US images of thyroid nodules surrounded by adequate thyroid tissue was classified as normoechoic and homogeneous were enrolled as study group. Forty-three US images from normal thyroid (NT) glands were included as controls. Digital images of 800 × 652 pixels were acquired at a resolution of eight bits with a 256 gray levels depth. By one-way ANOVA, the 43 NT glands were not statistically different (P = 0.91). Mean gray level of normal glands was significantly higher than b-BT (P = 0.026), and m-BT (P = 0.0001), while no difference was found between b-BT and m-BT (P = 0.321). NT tissue boundary external to the nodule was found at 6.0 ± 0.5 mm in cancers and 4.0 ± 0.5 mm in benignancies (P = 0.001). These data should indicate that the tissue surrounding a thyroid nodule may be damaged even when assessed as normal by US. This is of interest to investigate the extranodular effects of thyroid tumors

Centrifuge rolling test for ore liquefaction analysis

To study the development of liquefaction in ore cargo, a new Rolling Test has been designed to support similar stresses than those observed in a vessel. It can be used in an 80×g macrogravity field in the 5.5m radius Ifsttar geo-centrifuge. Its main characteristics are presented

A Variant of GJD2, Encoding for Connexin 36, Alters the Function of Insulin Producing β-Cells.

Signalling through gap junctions contributes to control insulin secretion and, thus, blood glucose levels. Gap junctions of the insulin-producing β-cells are made of connexin 36 (Cx36), which is encoded by the GJD2 gene. Cx36-null mice feature alterations mimicking those observed in type 2 diabetes (T2D). GJD2 is also expressed in neurons, which share a number of common features with pancreatic β-cells. Given that a synonymous exonic single nucleotide polymorphism of human Cx36 (SNP rs3743123) associates with altered function of central neurons in a subset of epileptic patients, we investigated whether this SNP also caused alterations of β-cell function. Transfection of rs3743123 cDNA in connexin-lacking HeLa cells resulted in altered formation of gap junction plaques and cell coupling, as compared to those induced by wild type (WT) GJD2 cDNA. Transgenic mice expressing the very same cDNAs under an insulin promoter revealed that SNP rs3743123 expression consistently lead to a post-natal reduction of islet Cx36 levels and β-cell survival, resulting in hyperglycemia in selected lines. These changes were not observed in sex- and age-matched controls expressing WT hCx36. The variant GJD2 only marginally associated to heterogeneous populations of diabetic patients. The data document that a silent polymorphism of GJD2 is associated with altered β-cell function, presumably contributing to T2D pathogenesis

Moving glass phase of driven lattices

We study periodic lattices, such as vortex lattices, driven by an external force in a random pinning potential. We show that effects of static disorder persist even at large velocity. It results in a novel moving glass state with topological order analogous to the static Bragg glass. The lattice flows through well-defined, elastically coupled, {\it % static} channels. We predict barriers to transverse motion resulting in finite transverse critical current. Experimental tests of the theory are proposed.Comment: Revised version, shortened, 8 pages, REVTeX, no figure

Equilibration and Dynamic Phase Transitions of a Driven Vortex Lattice

We report on the observation of two types of current driven transitions in metastable vortex lattices. The metastable states, which are missed in usual slow transport measurements, are detected with a fast transport technique in the vortex lattice of undoped 2H-NbSe$_2$. The transitions are seen by following the evolution of these states when driven by a current. At low currents we observe an equilibration transition from a metastable to a stable state, followed by a dynamic crystallization transition at high currents.Comment: 5 pages, 4 figure

Moving glass theory of driven lattices with disorder

We study periodic structures, such as vortex lattices, moving in a random potential. As predicted in [T. Giamarchi, P. Le Doussal Phys. Rev. Lett. 76 3408 (1996)] the periodicity in the direction transverse to motion leads to a new class of driven systems: the Moving Glasses. We analyse using several RG techniques the properties at T=0 and $T>0$: (i) decay of translational long range order (ii) particles flow along static channels (iii) the channel pattern is highly correlated (iv) barriers to transverse motion. We demonstrate the existence of the ``transverse critical force'' at T=0. A ``static random force'' is shown to be generated by motion. Displacements grow logarithmically in $d=3$ and algebraically in $d=2$. The persistence of quasi long range translational order in $d=3$ at weak disorder, or large velocity leads to predict a topologically ordered ``Moving Bragg Glass''. This state continues the static Bragg glass and is stable at $T>0$, with non linear transverse response and linear asymptotic behavior. In $d=2$, or in $d=3$ at intermediate disorder, another moving glass exist (the Moving Transverse Glass) with smectic quasi order in the transverse direction. A phase diagram in $T$ force and disorder for static and moving structures is proposed. For correlated disorder we predict a ``moving Bose glass'' state with anisotropic transverse Meissner effect and transverse pinning. We discuss experimental consequences such as anomalous Hall effect in Wigner crystal and transverse critical current in vortex lattice.Comment: 74 pages, 27 figures, RevTe