bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth of Diamond Films by Plasma CVD
Authors: Yugo Shigemi , Kimura Tadamsa , Kanai Hisayuki , Adachi Yoshio
Published: March 2011

Growth of filmy diamond crystals has been strongly desired, and the plasma CVD is expected as one of the growth techniques which provide high quality crystalline diamond films. This study deals with the growth of uniform crystalline diamond films by means of the plasma CVD. The main stress was laid on the effects of the surface treatments of the silicon substrate and the substrate potential on composition of deposited materials as well as on the morphology of diamond crystals grown on the substrate.
A mixture of methane (1%)/hydrogen with a pressure to 400 Pa was flown at a rate of 150 cc/min and was discharged by applying 200 W, 2.45 GHz microwave power. The Si substrates were heated to 850 ° C.
Nuclei for the diamond crystal growth were preferentially generated on the defect sites caused by the surface treatments. With increasing the substrate potential in the negative direction, the growth of silicon carbide was observed to increase. When the substrate was positively biased, filmy diamond layers were found to be deposited.
Refractory Semiconductors for High Temperature Thermoelectric Energy Conversion
Authors: Wood Charles
Published: March 2011

Thermoelectric energy conversion utilizing nuclear heat sources has been employed for several decades to generate power for deep space probes. In the past, lead telluride and, more recently, silicon-germanium alloys have been the prime choices as thermoelectric materials for this application. Currently, a number of refractory semiconductors are under investigation at the Jet Propulsion Laboratory in order to produce power sources of higher conversion efficiency and, thus, lower mass per unit of power output. Included amongst these materials are improved Si-Ge alloys, rare earth compounds and boron-rich borides. The criteria used to select thermoelectric materials, in general, and the above materials, in particular, will be discussed. The current state of the art and the accomplishments to date in thermoelectric materials research will be reviewed.
Bipolaron Formation in B12 and (B11C)+ Icosahedra
Authors: Howard I. A. , Beckel C. L. , Emin David
Published: March 2011

Boron carbides, B1-xCx with 0.085 ≤ × ≤ 0.200, generally contain both B12 and B11C icosahedra. However, the electronic transport with 0.1 ≤ × ≤ 0.2 is believed to occur by means of bipolaron hopping between only B11 C icosahedra [i]. We have calculated the changes in energy, atomic positlions and charge distribution when a pair of electrons is added to the isoelectronic icosahedral clusters B12 and (B11C)+. We simulate an icosahedron in a neutral lattice by bonding the icosahedral atoms to hydrogenic atoms which we constrain to be neutral. The computations are performed with a self-consistent molecular-orbital method, PRDDO.

We find a total energy reduction of -3.7 eV for two electrons added to a B12 icosahedron. Of this, -2.7 eV arises from the electrons filling the icosahedron's bonding orbitals. The remaining -1.0 eV comes from the contraction of the icosahedron's radius by -0.09 Å. For two electrons added to a (B11C)+ icosahedron we find a total energy reduction of -18.2 eV. Of this, -16.5 eV arises from filling the icosahedron's bonding orbitals. The remainder arises frop a -0.09 Å contraction of the icosahedron's radius. Thus, we find (B11C) icosahedra to be strongly energetically favored over B12 icosahedra as bipolaron sites.

The positive charge associated with a (B11C)+ icosahedron is distributed over the eleven boron atoms. Concomitantly, we find the added two electrons of the bipolaron to be distributed over all twelve sites of the B11C icosahedron. We find the energy difference between an electron pair added to B12 and (B11C)+ icosahedra to arise principally from the increased Coulomic attraction provided by the extra positive charge of the (B11C) icosahedron.
Synthesis of New Chalcogenide Materials. The Novel One-Dimensional Semiconductor K4 Ti3 S14
Authors: Sunshine Steven A. , Kang Doris , Ibers James A.
Published: March 2011

The use of A2 Q/Q melts (A - alkali metal, Q - S or Se) for the synthesis of new one-dimensional solid-state materials is found to be of general utility and is illustrated here for the synthesis of K4 Ti3 SI4. Reaction of Ti metal with a K2 S/S melt at 375°C for 50 h affords K4 Ti3 SI4. The structure possesses one-dimensional chains of seven and eightcoordinate Ti atoms with each chain isolated from all others by surrounding K atoms. There are six S-S pairs (dave - 2.069(3) Å) so that the compound is one of TiIV and may be described as K4 [Ti3 (S)2 (S2)6]. Electrical conductivity measurements indicate that this material is a semiconductor.
Nature of Paramagnetic Centers in Amorphous Boron
Authors: Tsiskarishvili G. P. , Tsagareishvili G. V. , Antadze M. E. , Tavadze F. N.
Published: March 2011

Amorphous powders of boron isotopes have been studied in the temperature range 100–450 K using EPR method. It was shown that paramagnetic centers with g=2.0029 ± 0.0001 are the holes captured on trapping levels. The centers represent volume defects. On the basis of temperature dependent measurements of the concentration of paramagnetic centers and their linewidth an energetical parameter of trapping level equal to 0.11eV over valence band was defined. An observed strong narrowing of the EPR line is connected with the increase of the frequency of delocalization of electrons with temperature. The structure of powders was studied by electron microscope method. Experimental results confirm the existence of icosahedral arrangement in amorphous boron.
Microscopic Origin of the Composition-Dependent Change of the Thermal Conductivity in Boron Carbides
Authors: Emin David , Howard I. A. , Green T. A. , Beckel C. L.
Published: March 2011

Large grain polycrystalline boron carbides have a high-temperature thermal conductivity which changes from being characteristic of a crystal to being glass-like as the carbon content is reduced from its maximal value. We relate this phenomenon, to compositional changes within the three-atom intericosahedral chains. With a reduction of the carbon concentration from its maximal concentration (20 %), a carbon atom within some of the three-atom (CBC) intericosahedral chains is replaced by a boron atom, thereby producing CBB chains. We estimate that the CBB chains are significantly softer than the CBC chains. Thus, with this reduction of carbon content the intericosahedral chains are inhomogeneously softened. This suppresses the coherent transport of heat through the chains. The remaining thermal transport occurs incoherently through vibrationally inequivalent structural units, i.e. “phonon hopping.”
Simultaneous Measurement of Particle Size and Temperature in a Plasma Torch
Authors: Fincke J. R. , Jeffery C. L. , Englert S. B.
Published: March 2011

Two coincidence techniques for simultaneously obtaining particle size and temperature in a plasma torch are described. The absolute magnitude of scattered laser light is used to determine particle size and particle temperature is determined from a two-color pyrometer technique. Typical results on alumina particles injected into a 7 kW plasma torch are presented.
The Application of Planar Laser-Induced Fluorescence as a Diagnostic in Plasma Processing
Authors: Partin J. K. , Fincke J. R. , Jeffery C. L. , Snyder S. C. , Batdorf J. A.
Published: March 2011

This paper reports an application of the planar laser-induced fluorescence (PLIF) technique to visualize species in a plasma jet. For the experiment, 10 μm manganese particles were injected through a center feed in the cathode of a 8 kW plasma torch. A tunable laser beam (−20 mJ/pulse) was focused by a cylinderical lens into a sheet, approximately 2.4 cm high and 550 μm thick, which passed through the center of the plasma plume, exciting manganese lying within the plane defined by the laser. The fluorescence generated was imaged onto a gated, intensified CID camera, converted to digital format, and processed by an image analyzer to form a 2-D map of the relative manganese vapor concentration within the plasma. The results of this proof-of-principle experiment demonstrate that the PLIF measurement holds considerable promise for obtaining simultaneous spatially resolved measurements of species concentration.
Spatially-Resolved Emission Profiles of Parallel Plate RF Glow Discharges
Authors: Roth Richard M.
Published: March 2011

An apparatus is described which can acquire, in less than a second, a spectrally-resolved, spatial profile of the light emitted from a parallel plate, rf glow discharge. This is achieved by imaging the discharge emission onto the entrance slit of a monochromator with its spatial integrity preserved. Then a spatially-resolved image is detected by an optical multichannel detector which is oriented parallel to the entrance slit. Spatial profiles from nonreactive gas discharges demonstrate that the symmetry of an rf discharge can be dramatically affected by the nature of the gas.
Deposition of A-Ge:H by Gef4/H 2 Glow Discharge
Authors: Slobodin D. , Aljishi S. , Wagner S.
Published: March 2011

Hydrogenated amorphous germanium (a-Ge:H) thin films have been grown by DC proximity glow discharge deposition using GeF,/H2 as the source gas mixture. The film growth rate decreases with increasing substrate temperature because of the temperature activation of the competitive “etching” reaction: GeF, + Ge -2GeF 2. At sufficiently high substrate temperature and GeF4, partial pressure, this reaction dominates and film growth is suppressed. The hydrogen fraction in the source gas mixture appears to determine the extent of decomposition of GeF4. The deposition rates of germanium films grown from SiF4/GeF4/H2 and Ar/GeF4,/H2 under similar gas fraction and discharge power conditions are compared. The results suggest that Si species catalyze the deposition of Ge in SiF4/GeF4/H2 glow discharges. a-Ge:H films grown from GeF4/H2 have optical, electronic and structural properties similar to films grown by GeH, glow discharge.
Thermal Reduction of Ilmenite Concentrates in a DC Transferred-ARC Plasma Furnace
Authors: Brent A. D. , Reid K. J.
Published: March 2011

The thermal reduction of ilmenite to produce a high grade titania slag and pig iron byproduct using a d.c. transferred-arc plasma furnace has been investigated. Small-scale (50 kVA) batch tests were conducted on three different ilmenite concentrates of widely differing chemical compositions and geological histories to assess the suitability of this reactor configuration for ilmenite smelting. The effects of reducing agent particle size and excess carbon on slag grade, titanium and iron recoveries, and reducing agent efficiency are discussed. A d.c. plasma furnace appears to be an ideal reactor for ilmenite smelting, although accurate control of the furnace thermal balance is essential if reaction between furnace refractories and the titania slag is to be avoided.
Functional Anatomy of Whitefly Organs Associated with Squash Leaf Curl Virus (Geminiviridae: Begomovirus) Transmission by the B Biotype of Bemisia tabaci (Hemiptera: Aleyrodidae)
Authors: Cicero Joseph M , Brown Judith K
Published: March 2011

The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is a sibling species group that transmits Squash leaf curl virus (SLCV) and other geminiviruses (Geminiviridae, genus Begomovirus) in a circulative and persistent manner. Using in situ hybridization, SLCV was localized in the primary salivary glands, the midgut, and the filter chamber of adults of the B biotype in the group. However, no SLCV particles were localized in the accessory salivary glands. The midgut loop was found to reside, fully or partially, in the abdomen or thorax in >8,000 dissections, indicating that it is capable of moving through the petiole, a constriction between the two body sections. When extended to its anterior-most position in the thorax, the midgut can make direct contact with the salivary glands, but evidence for direct transfer of virions is lacking. However, the widely presumed pathway of viral transport from the gut to the whitefly primary salivary glands can now be broadened to include both the blood and the possibility of direct transfer during contiguity of these two organs. Light microscopical observations indicated that the primary salivary gland consists of a central region flanked by two dark-staining regions, referred to as endcaps. Electron microscopical examination of extirpated and nonextirpated primary salivary glands revealed additional distinct regions and cell types. One such region, located between the central region and an endcap, was correlated directly to the region where virions have previously been immunolocalized.
Diversity, morphology, and phylogeny of coleoid cephalopods from the Upper Cretaceous Plattenkalks of Lebanon-Part I: Prototeuthidina
Authors: Fuchs Dirk , Larson Neal
Published: March 2011

Morphologic analyses of a large collection of coleoid cephalopods from the Lebanese Upper Cretaceous yielded a much higher diversity than previously assumed and revealed numerous extraordinarily well-preserved, soft-part characters. An analysis of the Prototeuthidina, a gladius-bearing group with a slender torpedo-shaped body, revealed two species:Dorateuthis syriacaandBoreopeltis smithin. sp. Previously unknown soft-part characters, such as the digestive tract, the gills, and the cephalic cartilage considerably improved our knowledge ofD. syriaca.Since none of the investigated specimens show more than eight arms, similarities with modern squids are regarded as superficial.Boreopeltis smithin. sp. is erected on the basis of its comparatively wideParaplesioteuthis-like gladius. The latter species represents the first unambiguous record of this genus in Upper Cretaceous deposits. Phylogenetic analyses indicate that the prototeuthidid clade consists of two lineages. The plesioteuthidid lineage originates from early JurassicParaplesioteuthisand leads toPlesioteuthisandDorateuthis.The other lineage is morphologically more conservative and leads toBoreopeltis.
New species of the rare early Eocene creodont Galecyon and the radiation of early Hyaenodontidae
Authors: Zack Shawn P.
Published: March 2011

Galecyon is one of the first appearing hyaenodontid creodonts, as well as one of the most poorly known. New specimens greatly improve our understanding of the morphology of this early Eocene genus, thereby enhance knowledge of the earliest radiation of Hyaenodontidae, and include the first associated upper dental remains, as well as fragmentary cranial remains. The new records substantially expand the stratigraphic range of the genus and allow recognition of two new species. The first, Galecyon peregrinus n. sp., is a small, early species that includes the first records of Galecyon from the earliest Eocene Wa-0 interval. The second, Galecyon chronius n. sp., is a large, terminal species, represented by numerous specimens that extend the range of the genus into the late Wasatchian. The type species, G. mordax, is restricted to specimens that are intermediate in size and stratigraphic position. Phylogenetic analysis of early hyaenodontids confirms the monophyly of Galecyon and places it basal to Prolimnocyon, Prototomus, and Pyrocyon. Arfia is identified as the earliest diverging hyaenodontid sampled, contrasting with prior support for a more crownward position. Prototomus martis is more closely allied to Pyrocyon than to other species of Prototomus. The three North American species of Galecyon form a probable anagenetic lineage.
Regime-Transitions in the 2003-2010 Iraq War: An Approach Based on Correlations of Daily Fatalities
Authors: Alvarez-Ramirez Jose , Rodriguez Eduardo , Tyrtania Leonardo , Urrea-Garcìa Galo R
Published: March 2011

This paper studied the dynamics of civilian and military fatalities in the Iraq War during the 2003-2010 period. R/S-scaling analysis, a method to characterize fractality and memory effects in sequences, was used to estimate time variations in the correlations of daily fatalities. Together with concepts from complex social networks and systems theories, the dynamics of correlations (measured in terms of the so-called scaling Hurst exponent) provide a framework to describe the Iraq War evolution and to evaluate the effects of the major military and political events. In terms of changes in a correlations parameter, five regimes in the evolution of the war were identified. The first regime, occurring in the first months after the invasion, corresponds to a conventional confrontation. In the second regime occurred in the last months of 2004, the dynamics of civilian fatalities evolved toward uncorrelated behavior, indicating that the occurrence of daily fatalities was basically governed by random processes. This is in contrast to the dynamics of military fatalities that showed increased correlations. The second regime can be seen as the advent of a chaotic episode where the different insurgency groups acted within an erratic, poorly coordinated, manner. In the third regime that occurred in the first two 2005 quarters, correlations of civilian fatalities increased and converged into the correlations patterns of military fatalities, and this was interpreted as the surging of a well-organized, although non-centralized, insurgency structure. The fourth regime lasted from mid-2005 to the last 2007 months and showed an important correlation decrement for the military fatalities. This was related to the clash of two antagonist war structures, namely, the traditional centralized Coalition Army and a non-centralized insurgent army. Finally, the fifth regime, from mid-2007 to date, is characterized by stable fatality dynamics converging to uncorrelated behavior. It is apparent that this behavior is related to the start of the endgame to achieve stable economy and government. The concept of a scale-free network was used to describe the insurgency operations and the subsequent war and political events oriented to incorporate the former Baath Party member in the formation of a national Iraqi government. It is concluded that, given the availability of data (fatalities, economic activity, migration, etc.) in contemporary conflicts, the usage of mathematical methods and tools would provide further insights of the conflict evolution and, in this way, help to design better policies and strategies to reduce the adverse effects of violence on civilians.
Modeling and Optimization of Mass Transfer during Osmosis Dehydration of Carrot Slices by Neural Networks and Genetic Algorithms
Authors: Mohebbi Mohebbat , Akbarzadeh-T Mohammad-R , Shahidi Fakhri , Zabihi Seyed Mohsen
Published: March 2011

Osmotic dehydration, as a minimal processing method, has found increasingly wide prospects during the past few decades. This process involves mass transfer which is commonly modeled by applications of different procedures, mostly based on Fick's law. In this research, we approach the modeling process by first obtaining experimental measurement of carrots solid gain and water loss under different conditions of solution concentrations ( 20, 40 and 60% w/w), temperatures ( 40, 60 and 80°C) as well as time intervals (1-6h). Then two paradigms of artificial neural networks (ANN), feed forward neural networks (FFNN) and radial basis function neural networks (RBFNN) are applied and compared for modeling this process. Additionally, genetic algorithm is used to determine optimal conditions for osmotic dehydration.
Unified model for p-n junction current-voltage characteristics
Authors: Cristea Miron
Published: March 2011

Current-voltage p-n junction characteristics have been analyzed mainly at low injection levels. The high injection level region of the I/V characteristic allows the possibility of determining basic parameters of the semiconductor material, like the bulk doping concentration and charge carrier lifetime. Based on a new theoretical model of the p-n junction characteristics, valid for both low level and high level regions, a new general equation of the p-n junction is presented. It can serve for parameter extraction of semiconductor devices.
Pattern of Abdominal Pain Presenting in a General Outpatient Clinic in Teaching Hospitals of Eastern Nepal
Authors: Poudel M , Bhandari R , Giri R , Ghimire A , Uprety S
Published: March 2011

Introduction: Abdominal pain is a frequent presentation in any general clinic setting. Acid peptic disease, cholelithiasis, parasitic infestations, renal colic, urinary infection, hepatitis, infective diarrhoea, dysmenorrhoea, pelvic pain, gastrointestinal malignancy problems are just a few of the frequently encountered causes of these presentations.Objectives: 1.To describe the pattern of clinical presentations of abdominal pain in a general clinic,2.To identify socio-demography profile of the patient presenting with abdominal pain. Methods: This was a cross-sectional study conducted in the general outpatient department (GOPD) of (BPKIHS) a teaching hospital for a period of three months. The record of all abdominal pain cases presenting to GOPD together with the diagnosis recorded by various doctors of GOPD. Results: The greater prevalence of pain abdomen in female (55%) were 20-39 years group and in male (35%) were in 40-59 years group. When compared to all cases of abdominal pain in which females (58%) were predominant more in this study, the most common site for pain was central abdomen. Conclusion: The study showed that the female gender were predominant in the case of abdominal pain compare to male group and according to the occupation house were predominant. Keywords: abdominal pain; BPKIHS; pain. DOI: 10.3126/hren.v9i1.4359Health Renaissance, 2011: Vol.9 No.1:31-34
Experimental Study on the Filling of Nano Structures with Infrared Mold Surface Heating
Authors: Lin H.-Y. , Chang C.-H. , Young W.-B.
Published: March 2011

In the fabrication of plastic components with micro or nano structures, injection molding is one of the simple and most cost-effective processes. In the injection molding process, a complete filling of the micro or nano structures is necessary to fabricate a successful product. However, it is difficult to fully fill nano structures with an aspect ratio close to one or higher by the conventional molding process. In this study, mold inserts with nano channels were constructed by a LIGA-like process. The effects of the processing parameters and infrared heating on the filling of the nano structures were explored experimentally. Increasing the mold temperature, pressure, or filling rate did not improve the filling distance in nano channels with the conventional molding process significantly. Thus, an infrared mold surface heating system was introduced to assist the molding of the nano structures. To enhance the heating efficiency and reduce the cycle time, a heat-resistant layer was inserted under the mold cavity. The heat resistant plate led the heating system to work more efficiently. It easily increased the surface temperature over the glass transition temperature of plastic, thus fully filling the nano structures.
Drug Treatment of Cancer Cell Lines: A Way to Select for Cancer Stem Cells?
Authors: Chiodi Ilaria , Belgiovine Cristina , Donà Francesca , Scovassi A. Ivana , Mondello Chiara
Published: March 2011

Tumors are generally composed of different cell types. In recent years, it has been shown that in many types of cancers a subset of cells show peculiar characteristics, such as the ability to induce tumors when engrafted into host animals, self-renew and being immortal, and give rise to a differentiated progeny. These cells have been defined as cancer stem cells (CSCs) or tumor initiating cells. CSCs can be isolated both from tumor specimens and established cancer cell lines on the basis of their ability to exclude fluorescent dyes, express specific cell surface markers or grow in particular culture conditions. A key feature of CSCs is their resistance to chemotherapeutic agents, which could contribute to the remaining of residual cancer cells after therapeutic treatments. It has been shown that CSC-like cells can be isolated after drug treatment of cancer cell lines; in this review, we will describe the strategies so far applied to identify and isolate CSCs. Furthermore, we will discuss the possible use of these selected populations to investigate CSC biology and develop new anticancer drugs.
Increase in Metabolic Syndrome-Related Hospitalizations in Relation to Environmental Sources of Persistent Organic Pollutants
Authors: Sergeev Alexander V. , Carpenter David O.
Published: March 2011

Evidence from cell studies indicates that persistent organic pollutants (POP) can induce insulin resistance, an essential component of the metabolic syndrome (MetS). We hypothesized that residential proximity to environmental sources of POP would be associated with the MetS in the population. The present study examined the association between residency in a zip code containing or abutting environmental sources of POP and MetS-related hospitalization rates. Hospitalization data were obtained from the New York Statewide Planning and Research Cooperative System. Relative risks (RR) were calculated as hospitalization rate ratios. Adjusted RR and their 95% confidence intervals (CI) were estimated by multivariable Poisson regression. A higher proportion of African Americans resided in POP zip codes compared to Caucasians (25.9% and 24.3%, respectively, p < 0.01). Residence in POP zip codes was associated with a statistically significant 39.2% increase in MetS-related hospitalization rates, adjusted for race, gender, and age (adjusted RR = 1.392, 95% CI: 1.032–1.879, p = 0.030). Increase in age was independently associated with higher MetS-related hospitalization rates (p for trend < 0.001). Our findings contribute to the body of evidence supporting the hypothesis of POP constituting an environmental risk factor for the MetS. Further studies investigating exposure to POP and insulin resistance are warranted.
Docetaxel-Loaded Pluronic P123 Polymeric Micelles: in Vitro and in Vivo Evaluation
Authors: Liu Zhihong , Liu Donghua , Wang Lili , Zhang Juan , Zhang Na
Published: March 2011

In this work, novel docetaxel (DTX) -loaded Tween 80-free Pluronic P123 (P123) micelles with improved therapeutic effect were developed. The freeze-dried DTX-loaded P123 micelles (DTX-micelles) were analyzed by HPLC, TEM and DLS to determine the DTX loading, micelle morphology, size, respectively. The in vitro cytotoxic activity of DTX-micelles in HepG2, A549 and malignant melanoma B16 cells were evaluated by MTT assay. The corresponding in vivo antitumor efficacy was assessed in Kunming mice bearing B16 tumor after intravenous administration. The DTX-loading and efficiency into the micelles were 2.12 ± 0.09% and 86.34 ± 3.32%, respectively. The DTX-micelles were spherical with a mean particle size of 50.7 nm and size distribution from 22 to 84 nm, which suggested that they should be able to selectively accumulate in solid tumors by means of EPR effect, with a zeta potential of −12.45 ± 3.24 mV. The in vitro release behavior of DTX from DTX-micelles followed the Weibull equation. Compared with Duopafei®, DTX-micelles showed higher cytotoxicity against HepG2 (P < 0.01), A549 (P < 0.05) and B16 (P < 0.01) cells. In addition, DTX-micelles exhibited remarkable antitumor activity and reduced toxicity on B16 tumor in vivo. The tumor inhibition rates (TIR) of DTX-micelles was 91.6% versus 76.3% of Duopafei® (P < 0.01). These results suggested that P123 micelles might be considered as an effective DTX delivery system.
Finding Emotional-Laden Resources on the World Wide Web
Authors: Knautz Kathrin , Neal Diane Rasmussen , Schmidt Stefanie , Siebenlist Tobias , Stock Wolfgang G.
Published: March 2011

Some content in multimedia resources can depict or evoke certain emotions in users. The aim of Emotional Information Retrieval (EmIR) and of our research is to identify knowledge about emotional-laden documents and to use these findings in a new kind of World Wide Web information service that allows users to search and browse by emotion. Our prototype, called Media EMOtion SEarch (MEMOSE), is largely based on the results of research regarding emotive music pieces, images and videos. In order to index both evoked and depicted emotions in these three media types and to make them searchable, we work with a controlled vocabulary, slide controls to adjust the emotions’ intensities, and broad folksonomies to identify and separate the correct resource-specific emotions. This separation of so-called power tags is based on a tag distribution which follows either an inverse power law (only one emotion was recognized) or an inverse-logistical shape (two or three emotions were recognized). Both distributions are well known in information science. MEMOSE consists of a tool for tagging basic emotions with the help of slide controls, a processing device to separate power tags, a retrieval component consisting of a search interface (for any topic in combination with one or more emotions) and a results screen. The latter shows two separately ranked lists of items for each media type (depicted and felt emotions), displaying thumbnails of resources, ranked by the mean values of intensity. In the evaluation of the MEMOSE prototype, study participants described our EmIR system as an enjoyable Web 2.0 service.
On the Optimal Identification of Tag Sets in Time-Constrained RFID Configurations
Authors: Vales-Alonso Javier , Bueno-Delgado María Victoria , Egea-López Esteban , Alcaraz Juan José , Pérez-Mañogil Juan Manuel
Published: March 2011

In Radio Frequency Identification facilities the identification delay of a set of tags is mainly caused by the random access nature of the reading protocol, yielding a random identification time of the set of tags. In this paper, the cumulative distribution function of the identification time is evaluated using a discrete time Markov chain for single-set time-constrained passive RFID systems, namely those ones where a single group of tags is assumed to be in the reading area and only for a bounded time (sojourn time) before leaving. In these scenarios some tags in a set may leave the reader coverage area unidentified. The probability of this event is obtained from the cumulative distribution function of the identification time as a function of the sojourn time. This result provides a suitable criterion to minimize the probability of losing tags. Besides, an identification strategy based on splitting the set of tags in smaller subsets is also considered. Results demonstrate that there are optimal splitting configurations that reduce the overall identification time while keeping the same probability of losing tags.
Réélaboration et structure : l’héritage dans la langue et en linguistique
Authors: Cotte Pierre
Published: March 2011

L’étude présente une nouvelle théorie de fonctionnement interne de la périphrase be-ing en anglais contemporain. Elle développe l’intuition que cette structure réélabore une conjugaison sous-jacente au présent en répétant des éléments de sa signification dans le participe et dans le verbe vecteur be. Elle tente de dériver les propriétés aspectuelles et autres de la forme du processus de la réélaboration.
Partners in Crime in the Setting of Recurring Cardiac Arrest
Authors: Papavasileiou Lida P. , Forleo Giovanni B. , Santini Luca , Martuscelli Eugenio , Romeo Francesco
Published: March 2011

No previous reports are available about the potential dramatic effects resulting from the combination of acquired long QT interval not associated to bradycardia and myocardial ischemia. We report the case of a man that during acute necrotic pancreatitis presented QT interval prolongation without bradycardia, TdP, and two episodes of cardiac arrest. A coronary angiogram revealed a subocclusive stenosis of left anterior descending coronary artery, treated with a percutaneous coronary intervention. After myocardial revascularization, even in presence of long QT interval, no arrhythmic events occurred suggesting the key role of myocardial ischemia in triggering TdP in acquired long QT even without bradycardia. ECG performed six months later, after complete recovery from pancreatitis, showed a normal QT interval.
Fibroblast Growth Factor-2 Enhances Expansion of Human Bone Marrow-Derived Mesenchymal Stromal Cells without Diminishing Their Immunosuppressive Potential
Authors: Auletta Jeffery J. , Zale Elizabeth A. , Welter Jean F. , Solchaga Luis A.
Published: March 2011

Allogeneic hematopoietic stem cell transplantation is the main curative therapy for many hematologic malignancies. Its potential relies on graft-versus-tumor effects which associate with graft-versus-host disease. Mesenchymal stromal cells (MSCs) possess immunomodulatory properties that make them attractive therapeutic alternatives. We evaluated thein vitroimmunosuppressive activity of medium conditioned by human MSCs from 5 donors expanded 13 passages with or without FGF-2. FGF-2 supplementation increased expansion 3,500- and 240,000-fold by passages 7 and 13, respectively. There were no differences in immunosuppressive activity between media conditioned by passage-matched cells expanded under different conditions, but media conditioned by FGF-treated MSCs were superior to population doubling-matched controls. The immunosuppressive activity was maintained in three of the preparations but decreased with expansion in two. The proliferation induced by FGF-2 did not result in loss of immunosuppressive activity. However, because the immunosuppressive activity was not consistently preserved, caution must be exercised to ensure that the activity of the cells is sufficient after extensive expansion.
Branched RNA: A New Architecture for RNA Interference
Authors: Aviñó Anna , Ocampo Sandra M. , Perales José Carlos , Eritja Ramon
Published: March 2011

Branched RNAs with two and four strands were synthesized. These structures were used to obtain branched siRNA. The branched siRNA duplexes had similar inhibitory capacity as those of unmodified siRNA duplexes, as deduced from gene silencing experiments of the TNF-α protein. Branched RNAs are considered novel structures for siRNA technology, and they provide an innovative tool for specific gene inhibition. As the method described here is compatible with most RNA modifications described to date, these compounds may be further functionalized to obtain more potent siRNA derivatives and can be attached to suitable delivery systems.
Zinc Supplementation againstEimeria acervulina-Induced Oxidative Damage in Broiler Chickens
Authors: Georgieva Nedyalka V. , Gabrashanska Margarita , Koinarski Ventsislav , Yaneva Zvezdelina
Published: March 2011

This study was undertaken to determine the dietary supplements of Zn containing diet on the antioxidant status in chickens experimentally infected withEimeria acervulina. The antioxidant status was monitored via determination of MDA concentrations and erythrocyte SOD and CAT activities, as well as vitamin E, vitamin C, Cu, and Zn in liver, muscle, and serum. The results showed increased MDA (), CAT (), and decreased SOD () in the infected birds. Significant changes in Cu and Zn concentrations and dramatically reduction of vitamin C and E concentrations in the infected chickens were found. The observed deviations in the studied enzymes and nonenzymatic parameters evidence the occurrence of oxidative stress following the infection and impaired antioxidant status of chickens, infected withEimeria acervulina. Our results proved the ameliorating role of CuZn(OH)3Cl (0.170 g per kg food) againstEimeria acervulina-induced oxidative damage in infected chickens.
Lattices with and lattices without spectral gap
Authors: Bekka Bachir , Lubotzky Alexander
Published: March 2011

Let

G=\boldsymbol{G}(\mathbb{k})

 be the

\mathbb{k}

-rational points of a simple algebraic group

\boldsymbol{G}

over a local field

\mathbb{k}

and let

\Gamma

be a lattice in

G

. We show that the regular representation

\rho_{\Gamma\backslash G}

of

G

on

L^2(\Gamma\backslash G)

has a spectral gap, that is, the restriction of

\rho_{\Gamma\backslash G}

to the orthogonal of the constants in

L^2(\Gamma\backslash G)

has no almost invariant vectors. On the other hand, we give examples of locally compact simple groups

G

and lattices

\Gamma

for which

L^2(\Gamma\backslash G)

has no spectral gap. This answers in the negative a question asked by Margulis. In fact,

G

can be taken to be the group of orientation preserving automorphisms of a

k

-regular tree for

k>2

.
On the difficulty of presenting finitely presentable groups
Authors: Bridson Martin R. , Wilton Henry
Published: March 2011

We exhibit classes of groups in which the word problem is uniformly solvable but in which there is no algorithm that can compute finite presentations for finitely presentable subgroups. Direct products of hyperbolic groups, groups of integer matrices, and right-angled Coxeter groups form such classes. We discuss related classes of groups in which there
does
exist an algorithm to compute finite presentations for finitely presentable subgroups. We also construct a finitely presented group that has a polynomial Dehn function but in which there is no algorithm to compute the first Betti number of its finitely presentable subgroups.
Interpolating coefficient systems and $p$-ordinary cohomology of arithmetic groups
Authors: Harder Günter
Published: March 2011

We present an approach to Hida’s theory of

p

-adically interpolating the ordinary cohomology of arithmetic groups and we discuss some application of this approach to special values of

L

-functions.
Words and mixing times in finite simple groups
Authors: Schul Gili , Shalev Aner
Published: March 2011

Let

w \neq

1 be a non-trivial group word, let

G

be a finite simple group, and let

w(G)

be the set of values of

w

in

G

. We show that if

G

is large, then the random walk on

G

with respect to

w(G)

as a generating set has mixing time 2.

This strengthens various known results, for example the fact that

w(G)^2

covers almost all of

G

.
Geometric cycles, Albert algebras and related cohomology classes for arithmetic groups
Authors: Schwermer Joachim
Published: March 2011

We discuss the construction of totally geodesic cycles in locally symmetric spaces attached to arithmetic subgroups in algebraic groups

G

of type

F_4

which originate with reductive subgroups of the group

G

. In many cases, it can be shown that these cycles, to be called geometric cycles, yield non-vanishing (co)homology classes. Since the cohomology of an arithmetic group is related to the automorphic spectrum of the group, this geometric construction of non-vanishing classes leads to results concerning the existence of specific automorphic forms.
Reduction theory of point clusters in projective space
Authors: Stoll Michael
Published: March 2011

We generalise earlier results of John Cremona and the author on the reduction theory of binary forms, whose zeros give point clusters in

\mathbb{P}^1

, to point clusters in projective spaces

\mathbb{P}^n

of arbitrary dimension. In particular, we show how to find a reduced representative in the SL(

n+1, \mathbb{Z}

)-orbit of a given cluster. As an application, we show how one can find a unimodular transformation that produces a small equation for a given smooth plane curve.
Euclidean distance matrices, semidefinite programming and sensor network localization
Authors: Alfakih Abdo Y. , Anjos Miguel F. , Piccialli Veronica , Wolkowicz Henry
Published: March 2011

The fundamental problem of distance geometry involves the characterization and study of sets of points based only on given values of some or all of the distances between pairs of points. This problem has a wide range of applications in various areas of mathematics, physics, chemistry, and engineering. Euclidean distance matrices play an important role in this context by providing elegant and powerful convex relaxations. They play an important role in problems such as graph realization and graph rigidity. Moreover, by relaxing the embedding dimension restriction, these matrices can be used to approximate the hard problems efficiently using semidefinite programming. Throughout this survey we emphasize the interplay between these concepts and problems. In addition, we illustrate this interplay in the context of the sensor network localization problem.
Surgical and Medical Management of Tertiary Hyperparathyroidism
Authors: Tominaga Yoshihiro
Published: March 2011

Persistent hyperparathyroidism (HPT) after successful kidney transplantation (RTx) (tertiary HPT; THPT) is a common complication in patients with RTx and may affect bone disease, deterioration of graft function and cardiovascular events. Parathyroidectomy (PTx) is the most successful treatment for resolving advanced HPT in patients with THPT. However, the surgical indications for THPT and timing of the operation are problematic because hypercalcemia can be resolved spontaneously. Subtotal and total PTx with autotransplantaion are widely accepted for THPT. The evidence to know which procedure is more appropriated could not be found. Recently the deterioration of kidney graft function after PTx for THPT has been reported and hypoparathyroidism after PTx may be avoided. Recently cinacalcet has been applied for patients with THPT and the medicine can dramaticaly control HPT and hypercalcemia. Possible risks of cinacalcet are hypocalcemia and increased calciuria and the approval for THPT remains highly controversial. A large number of prospective controlled clinical trial should be required.
Novel Germline SDHB Mutation in a 35-Year-Old Male with Malignant Bladder Paraganglioma
Authors: Elaraj Dina M , Sturgeon Cord , Heller Michael B , Aleppo Grazia
Published: March 2011

Objective

Up to 25% of pheochromocytomas and paragangliomas (PGL) are associated with germline mutations in RET, VHL, NF1, and subunits A, B, C, or D of succinate dehydrogenase (SDH). SDHB mutations are associated with malignant extra-adrenal PGL. Codon specific genotype-phenotype relationships have not been identified. Herein is described a case of malignant bladder paraganglioma from a novel W200R SDHB mutation. The literature is reviewed and clinical management is discussed.

Methods

Literature review was performed to analyze the relationship between SDHB and PGL, yielding 45 unique articles, which were reviewed and cross-referenced.

Results

SDHB mutations have a 50% penetrance by age 35, 1/3 of paragangliomas are multifocal, 31 to 48% are malignant, and 50 to 70% of these malignant PGL develop metastases.

Conclusion

Based on the aggressive nature of the SDHB mutation, we recommend preoperative staging, an aggressive treatment regimen, and intensive screening for recurrence.
Assessing the regional surface influence through Backward Lagrangian Dispersion Models for aircraft CO2 vertical profiles observations in NE Spain
Authors: Font A. , Morguí J.-A. , Rodó X.
Published: March 2011

Abstract. In this study the differences in the measured atmospheric CO2 mixing ratio at three aircraft profiling sites in NE Spain separated by 60 km are analyzed in regard to the variability of the surface fluxes in the regional surface influence area. First, the Regional Potential Surface Influence (RPSI) for fifty-one days in 2006 is calculated to assess the vertical, horizontal and temporal extent of the surface influence for the three sites at the regional scale (104 km2) at different altitudes of the profile (600, 1200, 2500 and 4000 meters above the sea level, m a.s.l.). Second, three flights carried out in 2006 (7 February, 24 August and 29 November) following the Crown Atmospheric Sampling (CAS) design are presented to study the relation between the measured CO2 variability and the Potential Surface Influence (PSI) and RPSI concepts. At 600 and 1200 m a.s.l. the regional signal is confined up to 50 h before the measurements whereas at higher altitudes (2500 and 4000 m a.s.l.) the regional surface influence is only recovered during spring and summer months. The RPSI from sites separated by 60 km overlap by up to 70% of the regional surface influence at 600 and 1200 m a.s.l., while the overlap decreases to 10–40% at higher altitudes (2500 and 4000 m a.s.l.). The scale of the RPSI area is suitable to understand the differences in the measured CO2 concentration in the three vertices of the CAS, as CO2 differences are attributed to local surrounding fluxes (February) or to the variability of regional surface influence as for the August and November flights. For these two flights, the variability in the regional scale influences the variability measured in the local scale. The CAS sampling design for aircraft measurements appears to be a suitable method to cope with the variability of a typical grid for inversion models as measurements are intensified within the PBL and the background concentration is measured every ~102 km.
Effect of permafrost thawing on organic carbon and trace element colloidal speciation in the thermokarst lakes of western Siberia
Authors: Pokrovsky O. S. , Shirokova L. S. , Kirpotin S. N. , Audry S. , Viers J. , Dupré B.
Published: March 2011

Abstract. To examine the mechanisms of carbon mobilization and biodegradation during permafrost thawing and to establish a link between organic carbon (OC) and other chemical and microbiological parameters in forming thermokarst (thaw) lakes, we studied the biogeochemistry of OC and trace elements (TEs) in a chronosequence of small lakes that are being formed due to permafrost thawing in the northern part of western Siberia. Twenty lakes and small ponds of various sizes and ages were sampled for dissolved and colloidal organic carbon, metals and culturable heterotrophic bacterial cell number. We observed a sequence of ecosystems from peat thawing and palsa degradation due to permafrost subsidence in small ponds to large, km-size lakes that are subject to drainage to, finally, the khasyrey (drained lake) formation. There is a systematic evolution of both total dissolved and colloidal concentration of OC and TEs in the lake water along with the chronosequence of lake development that may be directly linked to the microbial mineralization of dissolved organic matter and the liberation of the inorganic components (Fe, Al, and TEs) from the organo-mineral colloids. In this chronosequence of lake development, we observed an apparent decrease in the relative proportion of low molecular weight <1 kDa (1 kDa ~ 1 nm) OC concentration along with a decrease in the concentration of total dissolved (<0.45 μm) OC. This decrease was accompanied by an increase in the small size organic ligands (probably autochthonous exometabolites produced by the phytoplankton) and a simultaneous decrease in the proportion of large-size organic (humic) complexes of allochthonous (soil) origin. This evolution may be due to the activity of heterotrophic bacterioplankton that use allochthonous organic matter and dissolved nutrients originating from peat lixiviation. Most insoluble TEs demonstrate a systematic decrease in concentration during filtration (5 μm, 0.45 μm) exhibiting a similar pattern among different samples. At the same time, there is an increase in the relative proportion of large size particles over the <1 kDa fraction for most insoluble elements along the chronosequence of lake evolution. TEs are likely to be bound to colloidal OC and coprecipitate with the mineral (Fe, Al) part of the colloids. Upon progressive consumption of dissolved OC by the heterotrophic bacteria, there is liberation of Fe, Al, and insoluble TEs in the water column that may be subjected to coagulation in the form of particles or large-size mineral colloids.