NTT (Italy)

BACKGROUND AND PURPOSE: The intima-media thickness (IMT) of extracranial carotid arteries determined by B-mode ultrasound is a measurable index of the presence of atherosclerosis. The ultrasonographic scan protocol and the scan reading techniques used until now to measure IMT are, however, time consuming and require the participation of specialized research centers. In this study we present a cross-sectional study of 963 patients attending the Enrica Grossi Paoletti Center in Milan, Italy, with the aim of assessing whether ultrasonographic measurements of carotid artery in routine clinical practice can yield the same results as those obtained with quantitative methods used until now in clinical trials. METHODS: Maximum and mean maximum IMT of carotid arteries were assessed by B-mode ultrasound with the use of the electronic caliper of the machine in real time. RESULTS: The intraobserver and interobserver variability of IMT of carotid arteries performed with the electronic caliper in real time was similar to that of quantitative processing of frozen images (coefficients of variation of intraobserver and interobserver mean maximum IMT measurements were 4.2% and 7.3%, respectively). Carotid artery IMT thus measured correlated with most of the known atherosclerosis risk factors and discriminated between patients with and without previous history of cardiovascular events. IMT was linearly related to the total number of vascular risk factors both in the whole group and after stratification of patients into 3 age classes. CONCLUSIONS: These observations establish a strong correlation between B-mode imaging of carotid atherosclerosis evaluated in normal clinical practice and data provided by clinical trials and validate this simple reading technique as a means of identifying IMT as another possible risk factor in patients at high risk of vascular disease.

BACKGROUND AND PURPOSE: Inflammation plays a key role in cerebral ischemia through activation of microglia and infiltration by leukocytes. Flow cytometry is a well-established method for quantitative and qualitative analysis of inflammatory cells. However, this technique has not been applied to the study of cerebral ischemia inflammation. The aim of this study was to establish a flow cytometric method to measure inflammatory cells in ischemic brain. METHODS: To perform flow cytometry on brain tissue, we developed 2 cell-isolation methods based on different mechanical dissociation and Percoll gradient separation techniques. The methods were tested on a rat model of permanent middle cerebral artery occlusion. Morphological and immunophenotypic analyses, with the use of anti-CD11b, anti-CD45, and alphabeta T-cell receptor antibodies, were employed to identify and quantify inflammatory cells. RESULTS: Both methods gave consistent results in terms of yield and reproducibility. The cell suspension contained granulocytes, macrophages, lymphocytes, and neural cells. Morphological and immunophenotypic analyses enabled the identification of a cell-scatter gate (R1a) enriched in inflammatory cells. With both methods, a higher number of events in R1a were recorded in the ischemic hemisphere than in the nonischemic hemisphere (P< or =0.001). CD11b, CD45, and alphabeta T-cell receptor staining confirmed that this augmentation was a reflection of the increase in the number of granulocytes, cells of the monocytic lineage, and lymphocytes. CONCLUSIONS: Quantitative flow cytometric analysis of ischemic rat brain is feasible and provides a reliable and rapid assay to assess neuroinflammation in experimental models of brain ischemia.

Piezoelectric and elastic constants of lithium niobate single crystal were measured in the temperature range between 20°C and 200°C. These constants were obtained by measuring the resonant and antiresonant frequencies of the length-extensional mode of bars with various orientations. The measured constants are all of the piezoelectric strain constants and the dielectric constants and a part of the elastic compliances, namely, s E 11 , 2 s E 13 + s E 44 , s E 14 and s E 33 . Values at 20°C and their temperature dependence are as follows. The constants d and s are expressed in units of 10 -8 statcoulomb/dyn and 10 -12 cm 2 /dyn, respectively: d 15 =222[1+( T (^° C )-20)2.8×10 -4 ]; d 22 =62.3[1+( T -20)×2.4×10 -4 ]; d 31 =-2.59[1+( T -20)11×10 -4 ]; d 33 =48.7[1+( T -20)2.9×10 -4 ]; s 11 E =0.564×[1+( T -20)1.5×10 -4 ]; 2 s 13 E + s 44 E =1.39[1+( T -20)2.0×10 -4 ]; s 14 E = -0.084; s 33 E =0.494[1+( T -20)1.5×10 -4 ]; ε 11 T =84.6; ε 33 T =28.6; k 31 =0.02; k 22 =0.32; k 33 =0.47. The electromechanical coupling factor k ' 31 of z y w -45°-cut bar amounts to 0.50.

Human observers can distinguish the albedo of real-world surfaces even when the surfaces are viewed in isolation, contrary to the Gelb effect. We sought to measure this ability and to understand the cues that might underlie it. We took photographs of complex surfaces such as stucco and asked observers to judge their diffuse reflectance by comparing them to a physical Munsell scale. Their judgments, while imperfect, were highly correlated with the true reflectance. The judgments were also highly correlated with certain image statistics, such as moment and percentile statistics of the luminance and subband histograms. When we digitally manipulated these statistics in an image, human judgments were correspondingly altered. Moreover, linear combinations of such statistics allow a machine vision system (operating within the constrained world of single surfaces) to estimate albedo with an accuracy similar to that of human observers. Taken together, these results indicate that some simple image statistics have a strong influence on the judgment of surface reflectance.

The electrostriction and polarization in the perovskite-type ferroelectric ceramics have been calculated in the state under the arbitrary biasing field. Domain configurations produced by 180°-reversal or 90°-rotation have been represented here by the threshold angle θ 180 or θ 90 ; that is, domains, making smaller angles than θ 180 or θ 90 after the switching once occurs, are completely reoriented under the given bias. The electrostriction and polarization can be calculated as functions of θ 90 and θ 180 , from the spontaneous strain and polarization of the crystal. The spontaneous strain in the rhombohedral crystal has been found as (3/2)[(π/2)-α] for the first time. Bias dependence of θ 90 and θ 180 have been obtained from the experimental results on the basis of the present calculations. Some discrepancies between the results and the expectation based on the activation field considerations are presumably due to the mechanical stress accompanied with 90°-rotations, and to the interaction of 180°-reversals and 90°-rotations.

Growth feature of a LiNbO 3 crystal obtained by the pulling method has been studied. The formation of growth ridges was interpreted as the intermittent growth of the form {102̄}, which was the most readily grown form from the melt. The point group of the high temperature, paraelectric phase was uniquely determined as 3̄2/ m from the symmetry elements of the configuration of ridges. On (001̄) planes, the triangular etched hillocks were observed. Orientations of the hillocks on the antiparallel domains were related by 2-fold rotation axis parallel to [100] consistent with the phase transition of the type 3̄2/ m →3 m . The atomic arrangement in the form {102̄} was examined, and a three-dimensional framework of the corner-shared Nb-O octahedra, similar to the one in perovskite, was found.

Czochralski (CZ) silicon crystals with striation free and microscopic homogeneous dopant concentrations are grown under the presence of an axially symmetric vertical magnetic field. The thermal convections of 3.5 kg of molten silicon in a crucible are successfully suppressed by a magnetic field of more than 1000 Oe in strength. Many advantages are found for the method developed in comparison with the conventional transverse magnetic field method in use.

Temperature and bias characteristics of ceramics of Pb(Zr-Ti)O 3 and its families have been measured. Bias dependence can be understood with a schematic model on the reorientations of 180° and 90° domains. Dielectric and elastic anisotropies of the single crystal are expected to be larger in the rhombohedral phase than in the tetragonal one. Temperature dependence under fixed biases have led to a supposition that ε 11 and s 11 are more temperature dependent than ε 33 and s 33 , respectively. Physical constants of ceramics are not single-valued functions of polarization P * . This fact will support Marutake's criticism on the thermodynamic treatments of ceramics formerly reported. A trial of dividing P * into the increment P 180 * caused by 180°-reversals and that P 90 * by 90°-rotations make it possible to understand behaviors of piezoelectric constants d 31 * , g 31 * and coupling coefficient k r * versus P * . Constants d 31 * and k r * do not represent the degree of poling, and g 31 * will be recommended as its practical measure.

Piezoelectric and elastic constants of lithium tantalate single crystal were measured from room temperature up to the Curie point (630°C). These constants were obtained by measuring resonant and antiresonant frequencies of bars and plates with various orientations. Temperature dependence of piezoelectric constants was discussed on the basis of the electrostrictive effect in the paraelectric phase biased by spontaneous polarization. Anomalous behavior of d 33 and d 31 was well explained by the dielectric anomaly of ε 33 T .

The magnetic structure of Fe 2 As has been determined by neutron diffraction. The compound Fe 2 As is antiferromagnetic with the Néel point at about 80°C. Its magnetic structure is different from Mn 2 As. The coupling between layers of iron atoms Fe(II) located at (0, 1/2, z ) and (1/2, 0, \bar z ) is antiparallel, but the coupling between a layer of iron atoms Fe(I) located at (0, 0, 0), (1/2, 1/2, 0) and adjacent Fe(II) layers is parallel. The magnetic unit cell has the c -axis twice as large as that of the chemical unit cell. The magnetic moments are 1.28 and 2.05 Bohr magnetons for Fe(I) and Fe(II) atoms. respectively. The moments lie perpendicular to the c -axis.

Random number generators are essential for applications in information security and numerical simulations. Most optical-chaos-based random number generators produce random bit sequences by offline post-processing with large optical components. We demonstrate a real-time hardware implementation of a fast physical random number generator with a photonic integrated circuit and a field programmable gate array (FPGA) electronic board. We generate 1-Tbit random bit sequences and evaluate their statistical randomness using NIST Special Publication 800-22 and TestU01. All of the BigCrush tests in TestU01 are passed using 410-Gbit random bit sequences. A maximum real-time generation rate of 21.1 Gb/s is achieved for random bit sequences in binary format stored in a computer, which can be directly used for applications involving secret keys in cryptography and random seeds in large-scale numerical simulations.

Since triglycine sulphate crystal is centrosymmetric above the Curie point, the piezoelectricity in the ferroelectric phase is expected to be an “induced” one as in the case of barium titanate, distinct from an “intrinsic” piezoelectricity of rochelle salt. Temperature dependences of piezoelectric constants are measured by using various cuts of crystal, and some experiments on electrostrictive effect above the Curie point are performed as well. We then obtain electrostrictive constants, and the above expectation is confirmed in several points. Moreover, the phase transition is found not to be accompanied by any elastic change. Next, some effects of irradiation by x-ray and γ-ray on the piezoelectric constants are examined, and it will be shown that an irradiation is useful for preventing a diminution of piezoelectricity resulting from growth of antiparallel domains, especially near the Curie point.

A correct driving style can strongly affect the fuel consumption. This work proposes a method to quantify the driving style economy via inertial measurements. It presents a low-cost and vehicle-independent system for the acquisition of the variables related to the dynamics of a vehicle. Then it describes the signal processing and the algorithm which calculates the over-consumption of energy with respect to different reference profiles. Finally, experimental results show the application of the algorithm to real data gathered on public transportation means.

The effect of VLDL on plasminogen activator inhibitor type 1 biosynthesis in HepG2 cells was investigated. Exposure of HepG2 cells to VLDL (range, 10 to 100 micrograms protein per milliliter) for 16 hours resulted in an enhanced release of PAI-1 antigen and PAI activity into conditioned medium, accompanied by the accumulation of intracellular triglycerides. By using a monoclonal antibody (IgG C7) specific to the LDL receptor, we showed that the effect of VLDL is mediated by its interaction with the LDL receptor. Enhanced PAI-1 release was due to increased biosynthesis: PAI-1 mRNA was doubled, mainly because of the effect on the 2.2-kb PAI-1 mRNA rather than the 3.2-kb transcript. Addition of insulin with the VLDL further enhanced PAI-1 antigen release and PAI-1 mRNA accumulation. The effect of VLDL on steady state levels of PAI-1 mRNA was apparently not due to an increase of gene transcription but to stabilization of both PAI-1 mRNA transcripts. The enhancing effect of VLDL on PAI-1 biosynthesis in HepG2 cells may raise PAI-1 antigen levels not only in hypertriglyceridemic states but also in those conditions in which both insulin and VLDL are elevated.

1. Natura 2000 network ( N 2000) and national protected areas ( NPA s) are recognised as the most important core ‘units’ for biological conservation in E urope. 2. Species distribution models ( SDM s) were developed to detect the potential distribution of the rare and threatened cerambycid beetle Rosalia alpina L . in E urope, and the amount of suitable habitat within the N 2000 network [special areas of conservation ( SAC s) and special protection areas ( SPA s)], NPA s (e.g. national parks, regional parks, state reserves, natural monuments and protected landscapes) and the overall European protected area network ( EPAN ) ( N 2000 + NPA s) was quantified. 3. According to this analysis, the suitable habitat for R. alpina in E urope amounts to c . 754 171 km 2 and stretches across substantially uninterrupted areas from P ortugal to R omania (west to east) and from G reece to G ermany (south to north). The overlay between the existing system of conservation areas in E urope ( N 2000 and NPA s) and the binary map for R. alpina showed that only c . 42% of potential habitat is protected. SACs and SPA s protect c . 25% and 21% of potential habitat, respectively. However, because the two site types often spatially overlap, when taken together the entire N 2000 network protects c . 31% of potential habitat. Instead, NPA s offer a degree of protection of c . 29%. Overall, almost 60% of the area potentially suitable for the species is unprotected by the EPAN , an aspect that should be considered carefully when planning the conservation of this beetle at a large scale. 4. These results may also help to focus field surveys in selected areas where greater chances of success are encountered to save resources and increase survey effectiveness.

The thermal conductivity of KH 2 PO 4 , KD 2 PO 4 and KH 2 AsO 4 single crystals was measured in the temperature range from 4.5 to 300°K. For all the samples critical changes of the thermal conductivity are found at the Curie temperatures. The conductivity decreases gradually with falling temperature in the paraelectric state where the phonon mean free paths are limited by the disordered hydrogen atoms to the lattice spacings. It rises steeply just below the Curie temperature, increases exponentially with further temperature fall and attains to a maximum near 10°K. A marked isotope effect is observed in the maximum values of KH 2 PO 4 and KD 2 PO 4 . The former amounts to 600 mW/cm°K and the latter about 5500mW/cm°K. This effect may be attributed to the difference of hydrogen motions in the double-minimum potentials. The peak of KH 2 ASO 4 is only 220mW/cm°K. A small anisotropy in the conduction is found in the exponential variation range for these three crystals.

BACKGROUND AND PURPOSE: To evaluate whether high levels of low-density lipoprotein cholesterol (LDL-C) may promote the atherogenic effect of lipoprotein(a) [Lp(a)], we investigated the association between elevated Lp(a) levels and thickening of intima plus media in the common carotid artery (CC-IMT) in patients with different degrees of hypercholesterolemia. METHODS: One hundred type II hypercholesterolemic patients and 25 normolipidemic subjects were selected for the study. Plasma lipid and lipoprotein levels were determined enzymatically; Lp(a) levels were determined by enzyme-linked immunosorbent assay. An Lp(a) concentration > 30 mg/dL was arbitrarily considered a risk factor. For each patient mean CC-IMT was determined by B-mode ultrasound; in 60 patients and in the 25 control subjects, the maximal IMT in the entire carotid tree was also determined. RESULTS: CC-IMT values were higher in hypercholesterolemic patients with plasma Lp(a) levels > 30 mg/dL than in those with lower levels (P < .01). CC-IMT and maximal IMT directly and independently correlated with plasma levels of Lp(a) (r = .33 and r = .25, respectively; both P < .05). The effect of LDL-C concentrations on the relationship between IMT and Lp(a) was investigated by dividing the patients into quartiles of plasma LDL-C levels. After stratification, CC-IMT significantly correlated with plasma Lp(a) levels in the patients with severe hypercholesterolemia (LDL-C > 5.2 mmol/L) but not in patients in the lowest quartile, ie, those with moderate hypercholesterolemia. No correlation between CC-IMT and Lp(a) was found in normolipidemic control subjects. CONCLUSIONS: Elevated plasma levels of Lp(a) can be considered an additional independent factor associated with thickening of the common carotid arteries in patients with severe hypercholesterolemia but not in those with moderate hypercholesterolemia or in normocholesterolemic subjects.

Antiparallel domain configurations in c -plate crystal are observed in {003} x-ray reflection micrographs by the intensity contrast caused by anomalous scattering of the incident CrKα radiation by Ba and Ti atoms. The micrographs are taken with the scanning method of Lang applied to the reflection case. Measured ratio between | F (00\bar3)| 2 and | F (003)| 2 by a single-crystal-diffractometer amounts to 1.16. It is shown that with this reflection the antiparallel domains can be clearly discriminated in the x-ray reflection images with strong intensity contrast, and that the domain reversal process can be followed non-destructively.

The electrical properties of the conductive TiO2 (rutile) ceramics, as well as single crystals, doped with Nb2O5 or Ta2O5 were investigated by Hall effect and thermoelectric power measurements. These properties were shown to be strongly dependent on the doping concentration which covered the range up to 4 mole-percent. The experimental results indicate that the specimens are non-degenerated n-type semiconductor with a density-of-states effective mass of m*=20 m. At room temperature, where lattice scattering plays a dominant role, Hall mobility is about 0.4 cm2/Vs. for lower doping level and it falls down to 10-2 cm2/Vs. with the increasing doping concentration. The mobility increases in the slightly doped specimens at liquid nitrogen point, while it decreases in the specimens doped more heavily than 0.1 mole-percent. The activation energy of the donor centers due to the doping is 0.02 eV. The reduced specimen not intentionally doped, shows a shallower level nearly equal to 0.01 eV.

To assess the relationship between home blood pressure and left ventricular mass, we evaluated cardiac echocardiography in 297 hypertensive subjects (188 men and 109 women; mean age, 62.8+/-10.3 years) who were treated with amlodipine monotherapy over 1 year (mean dose, 5.5+/-2.3 mg/day). The morning hypertension group (n=57; 19.2%), who had a morning home systolic blood pressure (HSBP) > or =135 mmHg and an evening HSBP <135 mmHg, had a significantly greater left ventricular mass index (LVMI) concomitant with an increase in the homeostasis model assessment insulin resistance index (HOMA-IR) compared to the good control group (n=174; 58.6%), whose morning and evening HSBP were both <135 mmHg, and had a LVMI roughly equivalent to that of the poor control group (n=63; 21.2%), whose morning and evening HSBP were both > or =135 mmHg. By grouping of subjects according to the difference between morning and evening HSBP (delta HSBP), subjects with a delta HSBP> or =10 mmHg had a significantly greater LVMI than subjects with a delta HSBP <10 mmHg. Increases in LVMI in these patients were still significant after adjustment for age, gender, dose of amlodipine, alcohol consumption, body mass index, office systolic blood pressure, and morning and evening HSBP. In a stepwise multivariate regression analysis, delta HSBP (r2=36.2%, p <0.001), morning HSBP (r2=5.5%, p <0.001), HOMA-IR (r2=1.4%, p=0.016) and age (r2=1.0%, p=0.026) were determined to be significant contributing factors for LVMI. This regression model could explain 44.1% of LVMI variability. These results suggest that morning rise in blood pressure is a dominant predictor of left ventricular hypertrophy.