bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retinoic Acid Stimulates 17β-Estradiol and Testosterone Synthesis in Rat Hippocampal Slice Cultures
Authors: Munetsuna Eiji , Hojo Yasushi , Hattori Minoru , Ishii Hirotaka , Kawato Suguru , Ishida Atsuhiko , Kominami Shiro A. J. , Yamazaki Takeshi 
Published: June 2009

AbstractThe hippocampus is essentially involved in learning and memory processes. Its functions are affected by various neuromodulators, including 17β-estradiol, testosterone, and retinoid. Brain-synthesized steroid hormones act as autocrine and paracrine modulators. The regulatory mechanism underlying brain steroidogenesis has not been fully elucidated. Synthesis of sex steroids in the gonads is stimulated by retinoic acids. Therefore, we examined the effects of retinoic acids on estradiol and testosterone biosynthesis in the rat hippocampus. We used cultured hippocampal slices from 10- to 12-d-old male rats to investigate de novo steroidogenesis. The infant rat hippocampus possesses mRNAs for steroidogenic enzymes and retinoid receptors. Slices were used after 24 h of preculture to obtain maximal steroidogenic activity because steroidogenesis in cultured slices decreases with time. The mRNA levels for P45017α, P450 aromatase and estrogen receptor-β in the slices were increased by treatment with 9-cis-retinoic acid but not by all-trans-isomer. The magnitude of stimulation and the shape of the dose-response curve for the mRNA level for P45017α were similar to those for cellular retinoid binding protein type 2, the transcription of which is activated by retinoid X receptor signaling. 9-cis-Retinoic acid also induced a 1.7-fold increase in the protein content of P45017α and a 2-fold increase in de novo synthesis of 17β-estradiol and testosterone. These steroids may be synthesized from a steroid precursor(s), such as pregnenolone or other steroids, or from cholesterol, as so-called neurosteroids. The stimulation of estradiol and testosterone synthesis by 9-cis-retinoic acid might be caused by activation of P45017α transcription via retinoid X receptor signaling.
Novel Flow Cytometry–Based Screening for Bacterial Contamination of Donor Platelet Preparations Compared with Other Rapid Screening Methods
Authors: Dreier Jens , Vollmer Tanja , Kleesiek Knut 
Published: June 2009

AbstractBackground: Bacterial contamination is the major infectious hazard associated with transfusion of platelet preparations (PLTs). Routine testing for bacterial contamination in PLTs has become common, but transfusion-transmitted bacterial sepsis has not been eliminated. Here, we describe a novel flow cytometry–based method for point-of-issue screening of PLTs for bacterial contamination.Methods: We used the BactiFlow flow cytometer to detect and count bacteria based on esterase activity in viable cells. We compared the assay to incubation (BacT/Alert culture system) and rapid nucleic acid–based or immunoassay (reverse transcription PCR, Pan Genera Detection) methods.Results: We established a protocol for bacterial screening of PLTs consisting of enzymatic digestion and centrifugal filtration for the elimination of viable platelets and selective labeling of bacteria with fluorescent esterase substrate (ChemChrome V23). Results from the BactiFlow showed an excellent correlation (r = 0.9923 E. coli, r = 0.9736 S. epidermidis) to traditional plate count results. The lower detection limit of the assay was determined to be 150 CFU/mL, and the time to result was &lt;1 h.Conclusions: Our study demonstrates that BactiFlow flow cytometry is suitable for rapid screening of PLTs for bacterial contamination and fulfils the requirements for a point-of-issue testing of PLTs with acceptable time to result, specificity, sensitivity, and cost.
Chemerin is associated with markers of inflammation and components of the metabolic syndrome but does not predict coronary atherosclerosis
Authors: Lehrke Michael , Becker Alexander , Greif Martin , Stark Renee , Laubender Rüdiger P , von Ziegler Franz , Lebherz Corinna , Tittus Janine , Reiser Maximilian , Becker Christoph , Göke Burkhard , Leber Alexander W , Parhofer Klaus G , Broedl Uli C 
Published: June 2009

ObjectivesChemerin is a recently discovered adipokine that regulates adipocyte differentiation and modulates chemotaxis and activation of dendritic cells and macrophages. Given the convergence of adipocyte and macrophage function, chemerin may provide an interesting link between obesity, inflammation and atherosclerosis in humans. We sought to examine the relationship of i) chemerin and markers of inflammation, ii) chemerin and components of the metabolic syndrome, and iii) chemerin and coronary atherosclerotic plaque burden and morphology.DesignSerum chemerin levels were determined in 303 patients with stable typical or atypical chest pain who underwent dual-source multi-slice CT-angiography to exclude coronary artery stenosis. Atherosclerotic plaques were classified as calcified, mixed, or non-calcified.ResultsChemerin levels were highly correlated with high sensitivity C-reactive protein (r=0.44, P<0.0001), interleukin-6 (r=0.18, P=0.002), tumor necrosis factor-α (r=0.24, P<0.0001), resistin (r=0.28, P<0.0001), and leptin (r=0.36, P<0.0001) concentrations. Furthermore, chemerin was associated with components of the metabolic syndrome including body mass index (r=0.23, P=0.0002), triglycerides (r=0.29, P<0.0001), HDL-cholesterol (r=−0.18, P=0.003), and hypertension (P<0.0001). In bivariate analysis, chemerin levels were weakly correlated with coronary plaque burden (r=0.16, P=0.006) and the number of non-calcified plaques (r=0.14, P=0.02). These associations, however, were lost after adjusting for established cardiovascular risk factors (odds ratio, OR 1.17, 95% confidence interval (CI) 0.97–1.41, P=0.11 for coronary plaque burden; OR 1.06, 95% CI 0.96–1.17, P=0.22 for non-calcified plaques).ConclusionsChemerin is strongly associated with markers of inflammation and components of the metabolic syndrome. However, chemerin does not predict coronary atherosclerosis.
Thalidomide (Contergan) induced limb deficiency in Hungary?
Authors: Gidai János , Bács Éva , Czeizel Endre 
Published: June 2009

Esetismertetés
: Genetikai tanácsadónkban egy 47 éves, komplex végtaghiányos rendellenességben szenvedő nő jelentkezett és szakvéleményben kérte annak igazolását, hogy végtaghiányos rendellenességét a thalidomid (Contergan) nevű gyógyszer okozta. Édesanyja az ő születésével végződő terhességében állítólag szedte ezt a gyógyszert, amit Nyugat-Németországban élő nővérétől kapott. A thalidomid radialis-tibialis típusú végtaghiányos rendellenességet idéz elő, amely gyakran társul fülkagyló- és más rendellenességekkel. A thalidomidra jellemző végtaghiányos és más fejlődési rendellenesség azonban nála nem volt észlelhető. A nő komplex végtag-rendellenessége az úgynevezett FFU-komplexnek felelt meg, mivel femurhypoplasia (F), fibulahypoplasia (F) az V. és IV. lábujj hiányával mindkét alsó végtagján, valamint ulnaris hypoplasia (U) az V. és IV. ujj hiányával a jobb felső végtagon volt észlelhető, más fejlődési rendellenesség nélkül. Emellett schizophrenia miatt kezelték. Így az a korábban elfogadott feltételezés, hogy végtaghiányos rendellenességét a thalidomid okozta, kizárható volt.
Mechanism of oxide particle evolution in the MA957 ODS ferritic alloy
Authors: Sakasegawa H. , Legendre F. , Boulanger L. , Chaffron L. , Cozzika T. , Malaplate J. , Henry J. , Carlan Y. de , Brocq M. 
Published: June 2009

ABSTRACTIn our past work, two types of nanometer-sized oxide particle were found in the commercial ODS (Oxide Dispersion Strengthened) ferritic alloy MA957. They were nonstoichiometric Y-, Ti-, O-enriched clusters (2 ∼ 15 nm) and stoichiometric Y2Ti2O7 (15 ∼ 35 nm). The particles which have an important role for the strengthening were confirmed to be nonstoichiometric Y-, Ti-, O-enriched clusters (denoted by YxTiyOz in this work). Based on that result, the stability and evolution mechanism of oxide particle at high temperatures were studied in this work. After annealing (1473 K × 1 h), most of the non-stoichiometric YxTiyOz particles were stable and their size increased very little. However, some these particles apparently became Y2Ti2O7 particles with increasing size and yttrium content. They possibly contributed to the growth of Y2Ti2O7.
Metropolis Monte Carlo simulations of ordering and clustering in FeCr alloys
Authors: Zhurkin Evgeny E. , Pereira Romain , Castin Nicolas , Malerba Lorenzo , Hou Marc 
Published: June 2009

ABSTRACTThe Metropolis Monte Carlo (MMC) algorithm is a computational method to study equilibrium thermodynamic properties of a system at the atomic level. The algorithm accounts for all terms that contribute to defining the free energy difference between states: not only chemical, configurational and interfacial, but also due to strain fields and thermal vibrations. In this work, the MMC method with a two bands empirical many-body potential is used to predict the ordering properties of Fe1-xCrx alloys at various compositions and temperatures in the absence of defects. The particular goal of the work was to reveal the effect of atomic relaxations and vibrations on the phase diagram. It is found that vibrations and local relaxation effects contribute to lowering the order-disorder transition temperature by about 25 percent as compared to MMC predictions with a rigid lattice.
Transforming Orthopedic Biomaterials Into Bone Cancer Inhibiting Implants: The Role of Selenium Nanoclusters
Authors: Tran Phong A. , Sarin Love , Hurt Robert H. , Webster Thomas J. 
Published: June 2009

ABSTRACTCurrent orthopedic implants have numerous problems that include poor osseointegration, stress shielding and wear debris-associated bone cell death. In addition, numerous patients receive orthopedic implants as a result of bone cancer resection, yet none of the current orthopedic materials are designed to prevent either the occurrence or reoccurrence of cancer. The objective of this study was to transform a traditional orthopedic material into an implant that can both restore bone and prevent bone cancer growth at the implant-tissue interface. Elemental selenium was chosen as the biologically active agent in this material because of its known chemopreventive and chemotherapeutic properties. It was found that when selenite salts were reduced by glutathione in the presence of an immersed substrate (titanium (Ti), stainless steel (SS) or ultra high molecular weigh polyethylene (UHMWPE)), elemental selenium nucleated and grew into adherent, hemispherical nanoclusters. For each type of substrate (Ti, SS and UHMWPE), three types of surfaces with different selenium surface densities were fabricated. The zero oxidation state of selenium was confirmed on Ti substrates by XPS profiles. Compared to uncoated Ti and SS substrates, the high-density selenium-coated surfaces inhibited cancerous bone cell functions while promoting healthy bone cell functions. Very little selenium was also found to release (about 250ppb) into the cell culture media after 3 days of immersion. These findings showed for the first time the potential of using selenium nanoclusters as a coating to transform a traditional orthopedic material into a bone cancer inhibiting implant.
FET Characteristic of Chemically-Modified CNT
Authors: Kumashiro Ryotaro , Wang Yan , Komatsu Naoya , Tanigaki Katsumi 
Published: June 2009

AbstractElectric transport properties of chemically modificated carbon nanotubes (CNT) using Si-containing organic molecules and polymers were investigated by means of the field effect transistors (FET) technique. From the results of FET measurements for each chemically surface modified CNT, it was shown that p-type semiconducting CNT can be converted to n-type ones by physical adsorption of Si-containing organic molecules and polymers having Ph-groups. It is suggested that the electron carrier are doped into CNT from the adsorbed molecules and polymers, and it was also confirmed by the results of adsorption spectra. That is, it can be said that the electronic properties of CNT can be controlled by chemically modifications of outer surface.
Enhanced Performance of Organic Light Emitting Diodes Using LiF Buffer Layer
Authors: Vyavahare Omkar , Hailstone Richard 
Published: June 2009

AbstractSince the invention of organic electroluminescent devices, a great deal of effort has been made to improve their performance. Reducing the barrier and optimizing charge injection is crucial for efficient and bright Organic Light Emitting Diodes (OLEDs). We report the performance of OLEDs with ITO/TPD/Alq3/Al structure by inserting LiF both at electrode-organic interfaces and organic-organic interface. We elucidate the mechanism of the LiF buffer layer inserted at different interfaces. The device with LiF as a cathode injection layer shows improved luminescence and steeper IV characteristics.
Synchrotron Radiation and Conventional X-ray source photoemission studies of γ-Al2O3 thin films grown on Si(111) and Si(001) substrates by molecular beam epitaxy
Authors: El Kazzi Mario , Merckling Clement , Grenet Genevieve , Saint-Girons Guillaume , Silly Mathieu , Sirotti Fausto , Hollinger Guy 
Published: June 2009

AbstractHigh-resolution synchrotron radiation X-ray photoelectron spectroscopy (HRXPS) is used to study the chemical bonding at the Al2O3/Si(001) and Al2O3/Si(111) interfaces. In both cases, the Si2p spectra recorded at 180 eV photon energy provides evidence a thin interfacial layer rich in Si-O bonding. On the other hand, conventional AlKα X-ray source angular measurements clearly indicate that there are two in-plane orientations for Al2O3/Si(111) : [11-2]Al2O3(111)//[11-2]Si(111) and [-1-12] Al2O3(111)//[11-2]Si(111) but four in-plane orientations for Al2O3/Si(001) : [11-2] Al2O3(111)//[100]Si(001), [11-2]Al2O3(111)//[010]Si(001), [11-2]Al2O3(111)//[-100]Si(001), and [11-2]Al2O3(111)//[0-10]Si(001).
Crystallization Characteristics of Ge-Sb Phase Change Materials
Authors: Raoux Simone , Cabral Cyril , Krusin-Elbaum Lia , Jordan-Sweet Jean L. , Salinga Martin , Madan Anita , Pinto Teresa 
Published: June 2009

AbstractThe crystallization behavior of Ge-Sb phase change materials with variable Ge:Sb ratio X between 0.079 and 4.3 was studied using time-resolved x-ray diffraction, differential scanning calorimetry, x-ray reflectivity, optical reflectivity and resistivity vs. temperature measurements. It was found that the crystallization temperature increases with Ge content from about 130 °C for X = 0.079 to about 450 °C for X = 4.3. For low X, Sb x-ray diffraction peaks occurred during a heating ramp at lower temperature than Ge diffraction peaks. For X = 1.44 and higher, Sb and Ge peaks occurred at the same temperature. Mass density change upon crystallization and optical and electrical contrast between the phases show a maximum for the eutectic alloy with X = 0.17. The large change in materials properties with composition allows tailoring of the crystallization properties for specific application requirements.
Improved Fabrication Technique for Microstructured Solid-State Neutron Detectors
Authors: Bellinger Steven L , McNeil Walter J , McGregor Douglas Scott 
Published: June 2009

AbstractMicrostructured semiconductor neutron detectors have superior efficiency performance over thin-film coated planar semiconductor detectors. The microstructured detectors have patterns deeply etched into the semiconductor substrates subsequently backfilled with neutron reactive materials. The detectors operate as pn junction diodes. Two variations of the diodes have been fabricated, which either have a rectifying pn junction selectively formed around the etched microstructures or have pn junctions conformally diffused inside the microstructures. The devices with the pn junctions formed in the perforations have lower leakage currents and better signal formation than the devices with selective pn junctions around the etched patterns. Further, pulse height spectra from conformally diffused detectors have the main features predicted by theoretical models, whereas pulse height spectra from the selectively diffused detectors generally do not show these features. The improved performance of the conformal devices is attributed to stronger and more uniform electric fields in the detector active region. Also, system noise, which is directly related to leakage current, has been dramatically reduced as a result of the conformal diffusion fabrication technique. A sinusoidal patterned device with 100 μm deep perforations backfilled with 6LiF was determined to have 11.9 ± 0.078% intrinsic detection efficiency for 0.0253 eV neutrons, as calibrated with thin-film planar semiconductor devices and a 3He proportional counter.
Prospects for High Energy Resolution Gamma Ray Spectroscopy with Europium-Doped Strontium Iodide
Authors: Cherepy Nerine , Payne S A. , Hawrami Rastgo , Burger A , Boatner Lynn , Van Loef Edgar , Shah Kanai 
Published: June 2009

AbstractEuropium-doped strontium iodide scintillators offer a light yield exceeding 100,000 photons/MeV and excellent light yield proportionality, while at the same time, SrI2 is readily grown in single crystal form. Thus far, our collaboration has demonstrated an energy resolution with strontium iodide of 2.6% at 662 keV and 7.6% at 60 keV, and we have grown single crystals surpassing 30 cm3 in size (with lower resolution). Our analysis indicates that SrI2(Eu) has the potential to offer 2% energy resolution at 662 keV with optimized material, optics, and read-out. In particular, improvements in feedstock purity may result in crystal structural and chemical homogeneity, leading to improved light yield uniformity throughout the crystal volume, and consequently, better energy resolution. Uniform, efficient light collection and detection, is also required to achieve the best energy resolution with a SrI2(Eu) scintillator device.
Magnetron Sputtering for II-VI Solar Cells: Thinning the CdTe
Authors: Plotnikov Victor V. , Vasko Anthony C. , Compaan Alvin D. , Liu Xiangxin , Wieland Kristopher A. , Zeller Ryan M. , Li Jian , Collins Robert W. 
Published: June 2009

AbstractMagnetron sputtering (MS) of CdTe and related II-VI materials facilitates low energy ion and electron bombardment that promotes good film growth at substrate temperatures well below those needed for other physical vapor deposition methods. MS also provides good control of deposition rates while allowing scale-up to large areas. In this paper we review the use of MS for deposition of polycrystalline thin films of CdS, CdTe and related materials for solar cells with a focus on reducing the thickness. We relate the deposition conditions and plasma properties determined by Langmuir probe measurements to some of the materials properties of the films through spectroscopic ellipsometry and high resolution electron microscopy. For cells with CdTe layers from 0.35 to 2.5 μm, we have done a first-order optimization of chloride treatment conditions and back contact structure. We discuss the influence of CdTe thickness and post-deposition processing on the efficiency, open-circuit voltage, short-circuit current, and fill factor and show that 10% efficient cells can be fabricated with 0.5 μm of CdTe.
Short Time Transient Behavior of SiGe-based Microrefrigerators
Authors: Younes Ezzahri , Christofferson James , Maize Kerry , Shakouri Ali 
Published: June 2009

AbstractWe use a Thermoreflectance Thermal Imaging technique to study the transient cooling of SiGe-based microrefrigerators. Thermal imaging with submicron spatial resolution, 0.1C temperature resolution and 100 nanosecond temporal resolution is achieved. Transient temperature profiles of SiGe-based superlattice microrefrigerator devices of different sizes are obtained. The dynamic behavior of these microrefrigerators, show an interplay between Peltier and Joule effects. On the top surface of the device, Peltier cooling appears first with a time constant of about 10-30 microseconds, then Joule heating in the device starts taking over with a
time constant of about 100-150 microseconds. The experimental results agree very well with the theoretical predictions based on Thermal Quadrupoles Method. The difference in the two time constants can be explained considering the thermal resistance and capacitance of the thin film. In addition this shows that the Joule heating at the top metal/semiconductor interface does not dominate the microrefrigerator performance or else we would have obtained the same time constants for the Peltier and Joule effects. Experimental results show that under high current values, pulse-operation the microrefrigerator device can provide cooling for about 30 microseconds, even though steady state measurements show heating. Temperature distribution on the metal leads connected to the microrefrigerator’s cold junction show the interplay between Joule heating in the metal as well as heat conduction to the substrate. Modeling is used to study the effect of different physical and geometrical parameters of the device on its transient cooling. 3D geometry of heat and current flow in the device plays an important role. One of the goals is to maximize cooling over the shortest time scales.
Photocatalysis Approach for Energy and Environmental Challenges at Indian Institute of Chemical Technology, Hyderabad, India
Authors: Valluri Durga Kumari , Subrahmanyam Machiraju , Mangalampalli Venkata Phanikrishna Sharma , Jakkidi Krishna Reddy , Kannekanti Lalitha 
Published: June 2009

AbstractThe R & D developments in several aspects of catalysis area require cleaner and clean up technologies. Catalysts are used for energy conversion and to convert environmentally hazardous materials into harmless compounds. This presentation reviews the work currently under exploration at IICT that illustrates the perspective of photocatalyst technologies for solving energy and environmental issues for providing sustainable development. Studies on development of photocatalytic materials for degradation of phenolic wastes, common industrial effluent, H-acid, Calmagite (an azodye), Isopruturon (herbicide) and for E-coli disinfection are highlighted. Materials like Natrotantite, Ce-modified zeolites, Ag2O/TiO2, CuO/TiO2 and C,N-doped TiO2 are designed and evaluated for photocatalytic splitting of water for generation of hydrogen energy. Furthermore, potential applications of photo catalysts in the chemical synthesis of N-containing heterocyclic compounds like pyrazines and piperazines which are useful intermediates in the synthesis of various drugs, perfumes, herbicides and dyes are new interesting aspects in the presentation. Thus the present review describes the emerging trends in using photocatalysts for energy and environmental applications.
Novel Room-temperature Ferromagnetic Semiconductors Pb1-x-yCaxCryTe
Authors: Skipetrov Evgeny P. , Zvereva Elena A. , Pichugin Nikolay A. , Primenko Alexey E. , Slyn'ko Evgeny I. , Slyn'ko Vasily E. 
Published: June 2009

Abstract	The galvanomagnetic and magnetic properties of novel diluted magnetic semiconductors Pb1-x-yCaxCryTe (x=0.06-0.20, y=0.003-0.045) have been investigated. Temperature dependencies of the resistivity and the Hall coefficient have a metallic character indicating the pinning of Fermi level by the chromium impurity level on the background of the conduction band states. Magnetization curves display a clear hysteresis loop over the whole temperature range investigated. The Curie temperature, determined from the temperature dependencies of magnetization, achieves 345 K. Possible mechanisms of ferromagnetic ordering were discussed.