1.7 Volt, DC to 15 GHz Differential Amplifier with Constant Group Delay in InP-HBT Technology

10 dB gain–, 15 GHz-Bandwidth amplifier has been designed andfabricated in InP-HBT technology. Operation of the amplifier was achieved at1.7 V at total current consumption of 40 mA. The amplifier designed to havea Bessel-transfer-function has almost constant group delay up to 30 GHz.Pulse- and eye-diagram- measurements have been performed to verify largesignal operation. At 3.3 V, 24 dB gain and 10 GHz bandwidth was achieved.The 1dB compression point at 1.7 V supply voltage is measured at –10dBm output power.     

A specimen preparation technique for transmission electron microscopy of surface layers

A TEM specimen preparation method is described, with the aid of which electron transparent foils can be obtained across the external surface of a specimen. After careful pre-treatment, steel specimens have been electrolytically coated with nickel. Conventional thinning in a plane cutting the substrate-coating interface, gave thin foils displaying the internal structure as a function of depth under the initial free surface. The method has also been applied to minute metal particles, of dimensions too small to allow manipulating and foil preparation by conventional methods. Image examples are shown, and the applicability of the method is discussed.     

Quantitative analyses of carbonyl-carbon-11-WAY-100635 binding to central 5-hydroxytryptamine-1A receptors in man

The serotonin 5-hydroxytryptamine-1A (5-HT1A) receptor subtype is of central interest in research on the pathophysiology and treatment of psychiatric disorders. Carbonyl-11 C-WAY-100635 is a new radioligand that, in PET experiments, provides high-contrast delineation of brain regions that are rich in 5-HT1A receptors. The aim of this PET study was to examine the prospects for quantitation of carbonyl-11C-WAY-100635 binding to 5-HT1A receptors in the human brain. METHODS: A PET examination was performed in each of six healthy male subjects after intravenous injection of carbonyl-11C-WAY-100635. Radioactive metabolites in plasma were determined with high-performance liquid chromatography. The metabolite-corrected arterial input function was used in a kinetic three-compartment analysis, and the cerebellum was used as reference region in linear graphical and transient equilibrium analyses. RESULTS: The highest radioactivity concentration was observed in the neocortex and the raphe nuclei, whereas radioactivity was low in the cerebellum. The time-activity curves were well-described by a three-compartment model for all regions. Uptake in the cerebellum could not be described by a two-compartment model. The transient equilibrium and linear graphical analyses, which are both dependent on the cerebellum as the reference region, gave lower binding potential values than did the kinetic analysis. The metabolism was rapid, and the fraction of unchanged carbonyl-11C-WAY-100635 was <10% 10 min after injection in all human subjects. The major radioactive metabolites were unidentified polar components. One metabolite comigrated with reference cyclohexanecarboxylic acid, and another comigrated with reference desmethyl-WAY-100635. CONCLUSION: The suitability of carbonyl-11C-WAY-100635 for research on central 5-HT1A receptors in neuropsychiatric disorders was supported by the observation that the high signals in the neocortex and raphe nuclei can be described using a kinetic analysis with a metabolite-corrected arterial input function. It cannot be excluded that kinetically distinguishable nonspecific binding or the formation of a metabolite that passes the blood-brain barrier may represent measurable components of the low radioactivity in the cerebellum. Simplified quantitative methods, using the relatively low radioactivity in the cerebellum as reference, should accordingly be applied with some caution until the biochemical nature of the radioactivity is better understood and the reliability of these approaches has been confirmed in larger samples.     

Determination of conjugated monoamine metabolites in brain tissue

Levels of free and conjugated monoamine metabolites were analysed in brain tissue of rat and man. In the rat the conjugates were mainly of the sulfate ester type. The levels of conjugated dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) constituted 40--50% of the total amount of the metabolites. 4-Hydroxy-3-methoxy-phenylglycol (HMPG) and 5-hydroxy-3-indoleacetic acid (5-HIAA) were present as conjugates in 90 and 10% of the total levels. Chlorpromazine treatment resulted in an elevation of both the free and the conjugated forms of the dopamine metabolites and HMPG. In a human caudate nucleus obtained at autopsy both DOPAC and HMPG were present in the free form and as sulfate and glucuronide conjugates. The major dopamine metabolite found in this human brain was HVA. This metabolite and 5-HIAA occurred predominantly as free metabolites.     

Electro-Thermal Analysis of Multi-Fin Devices

As device dimensions shrink into the nanometer range, power and performance constraints prohibit the longevity of traditional MOS devices in circuit design. FinFETs, a quasi-planar double-gated device, has emerged as a replacement. While flnFETs provide promising electrostatic characteristics, they have the potential to suffer from significant self heating. We study in this paper self heating in multi-fin devices. We first develop thermal models for an individual fin with flared channel extensions and for multi-fin devices. We analyze several fin geometric parameters (fin width, and (gate) length) and investigate how fin spacing, fin height, gate oxide thickness and gate height affect the maximum fin temperatures in rectangular and flared channel extensions. Our data derived from numerical simulation validates our findings. We develop a novel metric, metric for electro-thermal sensitivity (METS), for measuring device thermal robustness. We use the metric to investigate electro-thermal device sensitivities. The metric, while applied to finFETs in this paper, is general and can be applied to any type of device for which coupled electrical and thermal models exist. Our work is the first to address thermal issues within multi-fin devices and to develop a widely-applicable electro-thermal metric.     

125I] beta-CIT-FE and [125I] beta-CIT-FP are superior to [125I] beta-CIT for dopamine transporter visualization: autoradiographic evaluation in the human brain

The binding of the three dopamine transporter radioligands ([125I] beta-CIT, [125I] beta-CIT-FE, and [125I] beta-CIT-FP) was studied using whole-hemisphere autoradiography on postmortem human brains. The autoradiograms revealed an intense and homogeneous labeling of the nucleus caudatus and putamen but also to varying extent to serotonergic and noradrenergic transporters of neocortex and thalamus. The order of specificity estimated (striatum over neocortex ratios) was beta-CIT-FP > beta-CIT-FE > > beta-CIT, suggesting that beta-CIT-FE and beta-CIT-FP should be preferred for in vivo studies of the dopamine transporter in the human brain.     

Quantitative digital evaluation of myocardial exercise thallium-201 single-photon emission tomography in post-menopausal women

OBJECTIVE: To determine the respective roles of septal fibrosis, necroinflammatory activity, iron deposition, steatosis, and patterns of nodular and septal remodeling in the collagenization of the perisinusoidal space in livers from patients undergoing transplantation for alcoholic or posthepatitis C cirrhosis and to ascertain whether perisinusoidal collagenization has clinical implications added to those of septal fibrosis. STUDY DESIGN: Sixty-six hepatectomy specimens from patients undergoing liver transplantation for cirrhosis were analyzed. Thirty-two alcoholic and 34 posthepatitis C cirrhoses were included. Picro Sirius-stained slides were examined with polarized light and the amount of perisinusoidal collagenization measured by computerized image analysis. Size distributions of septa and nodules were assessed by mathematical morphology methods. RESULTS: The septal and perisinusoidal fibrosis indices and Knodell and Pugh-Child scores showed significant differences between alcoholic and posthepatitis cirrhoses. Correlation between septal fibrosis and perisinusoidal collagenization was weak, though significant. Both variables correlated significantly with the clinical score. The correlation was negative between septal fibrosis or perisinusoidal collagenization and the Knodell score. CONCLUSION: Perisinusoidal collagenization was not a feature of all cases of cirrhosis, although it was more prominent in alcoholics. For the whole series, it significantly correlated with the clinical score, which increased significantly when high perisinusoidal collagenization was added to high septal fibrosis. No absolute dependence was found between perisinusoidal collagenization and septal fibrosis; percentage of slender fibrous septa and amount of iron deposition were other factors entered in the regression equation.