Inversion of the Diffraction Pattern from an Inhomogeneously Strained Crystal using an Iterative Algorithm

The displacement field in highly non uniformly strained crystals is obtained by addition of constraints to an iterative phase retrieval algorithm. These constraints include direct space density uniformity and also constraints to the sign and derivatives of the different components of the displacement field. This algorithm is applied to an experimental reciprocal space map measured using high resolution X-ray diffraction from an array of silicon lines and the obtained component of the displacement field is in very good agreement with the one calculated using a finite element model.Comment: 5 pages, 4 figure

The radon anomaly of Porcheresse (Ardennes, Belgium). A case study

From a very high radon concentration in a dwelling of the village of Porcheresse, one discusses on of the significance of the numerous radon indoor anomalies detected in the southern part of Belgium

Indoor radon levels in relation to geology in southern Belgium

A statistical study of an indoor radon data set of about 1700 short-term measurements shows a striking relationship between indoor radon concentration and the geological factors, such as stratigraphic unit and rock type

Integral correlation measures for multiparticle physics

We report on a considerable improvement in the technique of measuring multiparticle correlations via integrals over correlation functions. A modification of measures used in the characterization of chaotic dynamical sytems permits fast and flexible calculation of factorial moments and cumulants as well as their differential versions. Higher order correlation integral measurements even of large multiplicity events such as encountered in heavy ion collisons are now feasible. The change from ``ordinary'' to ``factorial'' powers may have important consequences in other fields such as the study of galaxy correlations and Bose-Einstein interferometry.Comment: 23 pages, 6 tar-compressed uuencoded PostScript figures appended, preprint TPR-92-4

Holocene tectonic, sedimentary, and erosive processes in a volcanic-dammed intramontane lacustrine basin: Lago Laja, Chile

Lago Laja is located near the drainage divide of the south-central high Andes at 37°S. The active Antuco volcano, adjacent to the lake, forms a natural dam confining the Laja intramontane basin. We use field observations, lake reflection-seismic profiles, bathymetry, and remote sensing data to reconstruct the late Quaternary erosion and sedimentation history of the Laja basin and to document the existence of an active fault system that runs parallel to the volcanic arc, the Lago Laja fault system (LLFS).Activity of the Antuco volcano started at ~124 ka with formation of the basaltic edifice, which dammed the catchments forming the intramone Laja basin and lake. At 7.1 cal ka BP, a caldera-collapse event of the Antuco opened the Laja’s dam generating an outburst megaflood and emptying the lake. Fluvial systems advanced into the former lake eroding the poorly-consolidated lacustrine sediments. Subsequent Late Holocene post-caldera lavas dammed the Laja’s outflow generating the present-day lake and renewed lacustrine sedimentation. The fluvial erosion episode is recorded in a regional unconformity, which is well observed in seismic profiles and thus represents an excellent structural marker to quantify fault activity. A post-7.1 ka lacustrine drape covers the erosional surface.Normal faults of the LLFS cut the -14 s-1. Pyroclastic deposits of the Chillan volcano in the northern segment yield a vertical slip rate of 1.0 ± 0.05 mm/a.We interpret soft-sediment deformation layers in an exposed late Pleistocene glaciolacustrine sequence as seismites, which evidence M>6 paleoearthquakes. This is in agreement with magnitudes expected from Holocene surface ruptures.The Main Cordillera at ~37°S is a large-scale pop-up structure uplifted by Quaternary thrusting along both its foothills. In this light, we interpret extension in the axial and highest part of the Andes as incipient gravitational collapse in response to surface uplift and crustal thickening. Thermal weakening due to elevated heat flow in the vicinity of the volcanic arc and post-glacial lithospheric rebound have probably contributed to the arc-limited collapse and late Quaternary acceleration of deformation rates

Neurohypophysial Receptor Gene Expression by Thymic T Cell Subsets and Thymic T Cell Lymphoma Cell Lines

Abstract Neurohypophysial oxytocin (OT) and vasopressin (VP) genes are transcribed in thymic epithelium, while immature T lymphocytes express functional neurohypophysial receptors. Neurohypophysial receptors belong to the G protein-linked seven-transmembrane receptor superfamily and are encoded by four distinct genes, OTR, V1R, V2R and V3R. The objective of this study was to identify the nature of neurohypophysial receptor in thymic T cell subsets purified by immunomagnetic selection, as well as in murine thymic lymphoma cell lines RL12-NP and BW5147. OTR is transcribed in all thymic T cell subsets and T cell lines, while V3R transcription is restricted to CD4+ CD8+ and CD8+ thymic cells. Neither V1R nor V2R transcripts are detected in any kind of T cells. The OTR protein was identified by immunocytochemistry on thymocytes freshly isolated from C57BL/6 mice. In murine fetal thymic organ cultures, a specific OTR antagonist does not modify the percentage of T cell subsets, but increases late T cell apoptosis further evidencing the involvement of OT/OTR signaling in the control of T cell proliferation and survival. According to these data, OTR and V3R are differentially expressed during T cell ontogeny. Moreover, the restriction of OTR transcription to T cell lines derived from thymic lymphomas may be important in the context of T cell leukemia pathogenesis and treatment

Decitabine impact on the endocytosis regulator RhoA, the folate carriers RFC1 and FOLR1, and the glucose transporter GLUT4 in human tumors.

BackgroundIn 31 solid tumor patients treated with the demethylating agent decitabine, we performed tumor biopsies before and after the first cycle of decitabine and used immunohistochemistry (IHC) to assess whether decitabine increased expression of various membrane transporters. Resistance to chemotherapy may arise due to promoter methylation/downregulation of expression of transporters required for drug uptake, and decitabine can reverse resistance in vitro. The endocytosis regulator RhoA, the folate carriers FOLR1 and RFC1, and the glucose transporter GLUT4 were assessed.ResultsPre-decitabine RhoA was higher in patients who had received their last therapy >3 months previously than in patients with more recent prior therapy (P = 0.02), and varied inversely with global DNA methylation as assessed by LINE1 methylation (r = -0.58, P = 0.006). Tumor RhoA scores increased with decitabine (P = 0.03), and RFC1 also increased in patients with pre-decitabine scores ≤150 (P = 0.004). Change in LINE1 methylation with decitabine did not correlate significantly with change in IHC scores for any transporter assessed. We also assessed methylation of the RFC1 gene (alias SLC19A1). SLC19A1 methylation correlated with tumor LINE1 methylation (r = 0.45, P = 0.02). There was a small (statistically insignificant) decrease in SLC19A1 methylation with decitabine, and there was a trend towards change in SLC19A1 methylation with decitabine correlating with change in LINE1 methylation (r = 0.47, P <0.15). While SLC19A1 methylation did not correlate with RFC1 scores, there was a trend towards an inverse correlation between change in SLC19A1 methylation and change in RFC1 expression (r = -0.45, P = 0.19).ConclusionsIn conclusion, after decitabine administration, there was increased expression of some (but not other) transporters that may play a role in chemotherapy uptake. Larger patient numbers will be needed to define the extent to which this increased expression is associated with changes in DNA methylation

Abnormal nociception and opiate sensitivity of STOP null mice exhibiting elevated levels of the endogenous alkaloid morphine

<p>Abstract</p> <p>Background-</p> <p>Mice deficient for the stable tubule only peptide (STOP) display altered dopaminergic neurotransmission associated with severe behavioural defects including disorganized locomotor activity. Endogenous morphine, which is present in nervous tissues and synthesized from dopamine, may contribute to these behavioral alterations since it is thought to play a role in normal and pathological neurotransmission.</p> <p>Results-</p> <p>In this study, we showed that STOP null brain structures, including cortex, hippocampus, cerebellum and spinal cord, contain high endogenous morphine amounts. The presence of elevated levels of morphine was associated with the presence of a higher density of mu opioid receptor with a higher affinity for morphine in STOP null brains. Interestingly, STOP null mice exhibited significantly lower nociceptive thresholds to thermal and mechanical stimulations. They also had abnormal behavioural responses to the administration of exogenous morphine and naloxone. Low dose of morphine (1 mg/kg, i.p.) produced a significant mechanical antinociception in STOP null mice whereas it has no effect on wild-type mice. High concentration of naloxone (1 mg/kg) was pronociceptive for both mice strain, a lower concentration (0.1 mg/kg) was found to increase the mean mechanical nociceptive threshold only in the case of STOP null mice.</p> <p>Conclusions-</p> <p>Together, our data show that STOP null mice displayed elevated levels of endogenous morphine, as well as an increase of morphine receptor affinity and density in brain. This was correlated with hypernociception and impaired pharmacological sensitivity to mu opioid receptor ligands.</p