bluuebunny/crossref_metadata_2025 huggingface dataset:
What Moves Macropartisanship? A Response to Green, Palmquist, and Schickler
Authors: Erikson Robert S. , Mackuen Michael B. , Stimson James A.
Published: May 2006

Contrary to the claim by Green, Palmquist, and Schickler (1998), macropartisanship is largely shaped by presidential approval and consumer sentiment. It is not the case, however, that macropartisanship mirrors the ever-changing levels of current presidential popularity and prosperity. Rather, macropartisanship reflects the cumulation of political and economic news that shapes approval and consumer sentiment. Using ECM technology, we show that, far from being the weak force that Green et al. suggest, the cumulation of innovations in presidential approval and consumer sentiment largely account for the long-term trends in macropartisanship. For forecasting macropartisanship in the near future, it is better to predict from the fundamentals represented by the history of approval and consumer sentiment up to a given moment than from current values of macropartisanship itself.
Fast Propene Dimerization Using Upper Rim‐Diphosphinated Calix[4]arenes as Chelators
Authors: Lejeune Manuel , Sémeril David , Jeunesse Catherine , Matt Dominique , Lutz Pierre , Toupet Loïc
Published: May 2006

The complexes [NiBr2⋅1] and [NiBr2⋅2], containing the upper rim‐diphosphinated calixarenes 5,17‐bis(diphenylphosphino)‐25,26,27,28‐tetrapropoxycalix[4]arene (1) and 5,17‐dibromo‐11,23‐bis(diphenylphosphino)‐25,26,27,28‐tetrapropoxycalix[4]arene (2) were assessed as propene dimerization catalysts. Combined with methylaluminoxane, both complexes result in highly efficient dimerization catalysts displaying C6 selectivities in the range 80–97% and activities that compare with the best reported systems, the latter using PCy3 as ligand. The origin of the remarkable activities of the calixarene derivatives may be the ability of the diphosphine to undergo a periodic bite angle increase that incidentally favors the insertion step. Calixarenes such as 1 or 2, which each incorporate two “stable” Ph2PAr moieties, constitute interesting alternatives to the use PCy3 in propene dimerization.
Homo‐ and Cross‐Olefin Metathesis Coupling of Vinylphosphane Oxides and Electron‐Poor Alkenes: Access to P‐Stereogenic Dienophiles
Authors: Vinokurov Nikolai , Michrowska Anna , Szmigielska Anna , Drzazga Zbigniew , Wójciuk Grzegorz , Demchuk Oleg M. , Grela Karol , Pietrusiewicz K. Michał , Butenschön Holger
Published: May 2006

Vinylphosphane oxides6undergo catalytic olefin homo‐metathesis leading to achiral and P‐stereogenic diphosphane dioxides7with exclusive (E)‐selectivity. Similarly, EWG‐substituted vinylphosphane oxides11, 12could be prepared with complete (E)‐olefin selectivityviaolefin cross‐metathesis with electron‐deficient substrates, such as methyl acrylate and 2‐fluorostyrene, using nitro‐Hoveyda ruthenium precatalystIII. Cross‐ and homo‐metathesis of chiral non‐racemic vinylphosphane oxides proceeds without racemization of the phosphorus center of chirality.
Radial artery as an autologous cell source for valvular tissue engineering efforts
Authors: Johnston Danielle E. , Boughner Derek R. , Cimini Massimo , Rogers Kem A.
Published: May 2006

To create a viable tissue‐engineered aortic valve, it is important to identify suitable autologous cell sources that may be seeded onto a biocompatible scaffold. This study focused on the radial artery (RA) as one possible source, investigated optimal culture conditions, and determined the usefulness of small intestinal submucosa (SIS) as a scaffold for tissue‐engineering. Porcine RA cells were cultured on either two‐dimensional (2D) 100‐mm dishes or three‐dimensional (3D) 1‐cm2 SIS sheets, producing cell–scaffold composites (CSCs). Both 2D and 3D cultures were maintained in either Medium 199 (M199) or endothelial growth media (EGM) to determine optimal growth conditions. Cellular phenotype and matrix metalloproteinase (MMP) profiles were determined by immunoblotting of cell lysates and zymography of conditioned media, respectively. Cellular invasion was analyzed immunohistochemically on CSC tissue sections. We show that the RA contains phenotypes consistent with those found in the normal aortic valve. EGM, compared with M199, promotes the invasion and remodeling of SIS by RA cells, which is crucial in the process of replacing the foreign tissue scaffold prior to implantation. To our knowledge, this is the first study to show that the RA is a suitable source for the generation of a tissue‐engineered valve. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Diversity attitudes and norms: the role of ethnic identity and relational demography
Authors: Linnehan Frank , Chrobot‐Mason Donna , Konrad Alison M.
Published: May 2006

This study investigated attitudes and subjective norms related to workplace diversity initiatives and intentions to engage in diversity‐related behaviors in a sample of 852 public service employees. Participants completed a survey measuring behavioral intentions, attitudes, belief‐based norms, ethnic identity achievement, and demographic characteristics. Comparisons were made between people of color and Whites as well as between those with high and low ethnic identity achievement. Results showed a triple interaction among supervisor race, employee race, and employee ethnic identity achievement. Specifically, among people of color with high ethnic identity achievement, having a supervisor of color was more strongly associated with positive views of subjective norms toward inclusive behavior, understanding others, and treating others with respect than among people of color with low ethnic identity achievement. Implications of these findings and directions for future research are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Photophysics and kinetics of naphthopyran derivatives, part 3: A general procedure to uniquely identify the kinetic and spectroscopic parameters of ABC(2k,2ϕ) systems and application to naphthopyran reactions
Authors: Maafi M. , Brown R. G.
Published: May 2006

A new procedure has been developed with the aim of determining the kinetic and spectroscopic parameters of any photochemical systems of the generic ABC(2k,1ϕ) and ABC(2k,2ϕ) types. General expressions of the colorability and the equilibrium concentration ratio of two (of the three involved) species at a photostationary state or a state of thermal equilibrium have been derived. The procedure has been successfully applied to achieve unique identifiability for the seven sequences of the ABC(2k,1ϕ and 2ϕ) type that may represent naphthopyran dynamics. It is demonstrated that the reactivity of this particular compound is certainly described by a higher kinetic level than those (three or four reaction steps) considered in the present study. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 421–430, 2006
The bacterial quality of red meat and offal in Casablanca (Morocco)
Authors: Cohen Nozha , Ennaji Hayat , Hassa Mohammed , Karib Hakim
Published: May 2006

The present study aimed to evaluate the bacteriological quality of beef (n = 52), lamb (n = 52) and beef offal (n = 52) marketed in Casablanca, Morocco. Meat and offal samples (n = 156), were collected randomly from butcheries, supermarkets, and slaughterhouses. Two sampling periods were considered, one during the hot season and the second one during the cold season. The samples were analyzed for the presence of the following bacteria: Escherichia coli, coagulase‐positive Staphylococcus, Clostridium perfringens, Salmonella, and Listeria monocytogenes. Results indicated that counts of the aerobic plate count, and fecal coliforms were particularly high in all the samples analyzed. E. coli, coagulase‐positive Staphylococcus and C. perfringens were detected in 37.8, 16, and 4.5% of the meat samples, respectively. Neither Salmonella nor L. monocytogenes were isolated from meat samples. Approximately 26.9% of beef, 34.6% of lamb and 28.8% of beef offal samples contained bacteria above the maximum limits established by the Moroccan regulatory standards for meat and meat products. Seasonality and the distribution location significantly (p < 0.05) affected bacterial populations: the hot season and butcheries appeared to be cases where the highest populations of bacteria in meat were observed. These high levels of microbiological contamination attest the poor hygienic quality of meat and offal, possibly due to uncontrolled processing, storage, and handling of these products.
The motion of a droplet subjected to linear shear flow including the presence of a plane wall
Authors: Uijttewaal W. S. J. , Nijhof E. J.
Published: May 2006

A fluid droplet subjected to shear flow deforms and rotates in the flow. In the presence of a wall the droplet migrates with respect to a material element in the undisturbed flow field. Neglecting fluid inertia, the Stakes problem for the droplet is solved using a boundary integral technique. It is shown how the time-dependent deformation, orientation, circulation and droplet viscosity. The migration velocities are calculated in the directions parallel and perpendicular to the wall, and compared with theoretical models and expeeriments. The results reveal some of the shortcomings of existiong models although not all diserepancies between our calculations and known experiments could be clarified.
Weakly nonlinear analysis of convection in mushy layers during the solidification of binary alloys
Authors: Anderson D. M. , Worster M. Grae
Published: May 2006

We consider the solidification of a binary alloy in a mushy layer and analyse the system near the onset of buoyancy-driven convection in the layer. We employ a neareutectic approximation and consider the limit of large far-field temperature. These asymptotic limits allow us to examine the rich dynamics of the mushy layer in the form of small deviations from the classical case of convection in a horizontal porous layer of uniform permeability. Of particular interest are the effects of the asymmetries in the basic state and the non-uniform permeability in the mushy layer, which lead to transcritically bifurcating convection with hexagonal planform. We obtain a set of three coupled amplitude equations describing the evolution of small-amplitude convecting states in the mushy layer. These equations are analysed to determine the stability of and competition between two-dimensional roll and hexagonal convection patterns. We find that either rolls or hexagons can be stable. Furthermore, hexagons with either upflow or downflow at the centres can be stable, depending on the relative strengths of different physical mechanisms. We determine how to adjust the control parameters to minimize the degree of subcriticality of the bifurcation and hence render the system globally more stable. Finally, the amplitude equations reveal the presence of a new oscillatory instability.
Die Ösophagus-/Fundus-Varizen-Blutung
Authors: De Gottardi  , Dufour
Published: May 2006

Ösophagus- und Fundus-Varizen sind eine häufige Komplikation der Leberzirrhose und der portalen Hypertonie. Wegen ihrer hohen Mortalität, sind Ösophagus- und Fundus-Varizenblutungen eine besondere Herausforderung sowohl für Notfallmediziner, als auch für Gastroenterologen. Zur Übernahme des Patienten mit einer Varizenblutung gehören in erster Linie eine enge Überwachung der Kreislauf- und Atemparameter sowie, bei Bedarf, die Verabreichung von Plasmaexpander und Blutkonserven, zur hämodynamischen Stabilisation. Mortalität und Morbidität werden außerdem mit der Anwendung von Antibiotika und vasoaktiven Medikamenten signifikant verbessert. Eine Gastroskopie zur Diagnosestellung und zur Therapie soll in der Regel nicht später als 12 Stunden nach dem Beginn der Blutung erfolgen. Die wichtigsten Behandlungsmöglichkeiten bestehen in der Einlage elastischer Ligaturen auf die Varizen, in der Sklerosierung der Varizen oder in der Injektion eines Klebstoffmittels an der Blutungsstelle. Bei Rezidivblutungen stehen, außer den oben genannten Methoden, die Einlage eines transjugulären portocavalen Shunts (TIPS), chirurgische Shuntsverfahren oder Embolisationen splanchnischer Gefäße zur Verfügung. Diese Maßnahmen sind allerdings mit einer hohen Mortalität assoziiert und sollen von einem interdisziplinären Team jeweils besprochen werden. Neben der Verbesserung der aktuellen medikamentösen und endoskopischen Therapiemöglichkeiten, gehört die Behandlung mit Koagulationsfaktoren zu den möglichen zukünftigen Angriffspunkten.
Behandlung der Blutung unter Antikoagulation
Authors: Korte
Published: May 2006

Die Zunahme kardiovaskulärer Erkrankungen führt auch zur Zunahme postinterventioneller prophylaktischer Therapien mit dem Ziel, okklusive thrombotische Veränderungen zu verhindern. Die postinterventionelle Prophylaxe im arteriellen Stromgebiet wird heute im wesentlichen durch eine antithrombozytäre Medikation sichergestellt; dabei erlaubt die Kombination von Substanzen mit verschiedenen Wirkungsmechanismen eine maximale antithrombozytäre Wirkung. Gleichzeitig führt diese maximierte Therapie aber auch zu einer erhöhten Blutungsneigung. Dies ist insbesondere bei polymedizierten Patienten zu beachten, da viele der bei kardiovaskulären Patienten eingesetzten Substanzen bereits eine Thrombopathie auslösen können. Dagegen wird die langfristige Prophylaxe venöser Thrombemebolien bzw. die Prophylaxe bei Vorhofflimmern oder künstlichen Herzklappen – bis auf wenige Ausnahmen – weiterhin mittels Coumarinen durchgeführt. Hier ist die möglichst genaue Einhaltung des INR-Zielwertes von 2.5 (Bereich 2.0–3.0) wichtig, da ein Unterschreiten des therapeutischen Bereiches zu einer erhöhten Thrombembolierate, ein Überschreiten zu einer erhöhten Blutungsrate führt. Bei Patienten mit Tumorerkrankungen scheint die Rezidiv-Prophylaxe mit niedrig molekularem Heparin derjenigen mit Coumarinen überlegen; daneben scheinen niedrig molekulare Heparine eine antimetastatische Wirkung zu vermitteln. Von pharmakokinetischer Relevanz beim Einsatz niedrig molekularer Heparine ist die Beachtung einer allfällig bestehenden Niereninsuffizienz, um eine Kumulation zu vermeiden. Tritt während einer Therapie mit Heparin(en) eine Thrombose oder ein deutlicher Thrombozytenabfall auf, so sollte die Differentialdiagnose einer heparin-induzierten Thrombopenie in Betracht gezogen werden, da sich hieraus unter Umständen vital relevante Konsequenzen ergeben können. Die vorliegende Übersichtsarbeit bespricht die wesentlichen Indikationen, die möglichen Nebenwirkungen und die Therapie möglicher Nebenwirkungen beim Einsatz von Antikoagulantien.
Aufrechterhaltung der Laktation bei Brustabszess
Authors: Cignacco Eva , Zbinden Astrid , Surbek Daniel
Published: May 2006

Die Entwicklung eines Abszesses der laktierenden Brust ist eine nicht seltene Pathologie. Eine rechtzeitige Erkennung der Symptomatik und die rasch einsetzende Therapie sind für die Aufrechterhaltung der Laktation und die Vermeidung von Folgekomplikationen von Bedeutung. Im Genesungsprozess sind somatische und psychologische Aspekte zu berücksichtigen. Spezialisierte Hebammen und Pflegefachpersonen leisten in der Gesundheitsförderung betroffener Mütter einen wichtigen Beitrag.
Erhebung und Bewertung der Gesundheitsverträglichkeit der Arbeitszeitmodelle Schweizer Intensivpflegestationen
Authors: Busch Ada-Katrin , Reuter Harald , Bauer Georg
Published: May 2006

Arbeitszeitregelungen gehören zu den größten gesundheitlichen Belastungsquellen im Beruf der Gesundheits- und Krankenpflege. Je nach Ausformung können sie sowohl die physische und psychische Gesundheit als auch die soziale und private Integration der Pflegenden gefährden. Die zusätzlichen Belastungen des pflegerischen Alltags, mit denen sich in besonderem Maße das Intensivpflegepersonal konfrontiert sieht, verstärken diese Effekte. Um Hinweise auf Vor- und Nachteile alternativer Modelle sowie praktikable Lösung in Bezug auf gesundheitsverträgliche Arbeitszeitformen zu erhalten, bestanden die Ziele dieser explorativen Studie darin, den Bestand der auf den Intensivpflegestationen der Schweiz praktizierten Arbeitszeitmodelle aufzunehmen, die erfassten Modelle hinsichtlich ihrer Gesundheitsverträglichkeit zu bewerten und eine Analyse der organisatorischen Rahmenbedingungen der Stationen mit besonders gesundheitsverträglichen Modellen vorzunehmen. Es wurde ein Fragebogen entwickelt, mit dem 84 Pflegefachpersonen, die für die Gestaltung der Dienstpläne auf den Intensivpflegestationen zuständig sind, befragt wurden. Die Daten wurden mittels deskriptiver statistischer Methoden analysiert. Für die Bewertung der Gesundheitsverträglichkeit wurde ein Verfahren entwickelt, das die wichtigsten gesundheitsrelevanten Dimensionen von Arbeitszeitmodellen berücksichtigt und eine Gesamteinschätzung der verschiedenen praktizierten Arbeitszeitmodelle erlaubt. Ein Extremgruppenvergleich unter Inanspruchnahme von nicht-parametrischen und parametrischen Tests diente der Analyse der organisatorischen Rahmenbedingungen. Die Ergebnisse der Untersuchung zeigen auf, dass die Gestaltung der Arbeitszeit auf den Intensivpflegestationen der Schweizer Spitäler hinsichtlich der arbeits- und gesundheitswissenschaftlichen Erkenntnisse noch nicht optimal erfolgt. Verbesserungspotenzial ist insbesondere in den Dimensionen Dauer und Dichte der Arbeitszeiten und bei den unterstützenden Angeboten der Betriebe erkennbar
Role of heterotrophic dinoflagellate Gyrodinium sp. in the fate of an iron induced diatom bloom
Authors: Saito Hiroaki , Ota Takashi , Suzuki Koji , Nishioka Jun , Tsuda Atsushi
Published: May 2006

Iron enrichment to high‐nutrient low‐chlorophyll (HNLC) regions is being considered as a possible way of atmospheric CO2 sequestration to the deep sea. Mesoscale iron‐enrichment to the HNLC subarctic Pacific induced a massive diatom bloom and led to a large decrease in pCO2. In response to the diatom bloom, the heterotrophic dinoflagellate Gyrodinium sp. increased and phagotrophically fed on the diatoms up to 12 times their length. Mathematical simulations show the carbon fixed by diatoms is mostly respired by Gyrodinium sp. in the sea surface. The emergence of initially rare species and their key biogeochemical roles were unexpected due to our limited understanding of food‐web components. This indicates that the prediction of ecosystem responses to natural or anthropogenic perturbation remains a challenging issue. Effective carbon sequestration as a geoengineering technique may not be accomplished by purposeful iron‐enrichment, at least in the western subarctic Pacific where rapid‐growth diatom grazers stand by.
Comparison of ground‐based and airborne snow surface albedo parameterizations in an alpine watershed: Impact on snowpack mass balance
Authors: Molotch Noah P. , Bales Roger C.
Published: May 2006

Two commonly used snow surface albedo models were evaluated using albedo data from the Airborne Visible/Infrared Imaging Spectroradiometer (AVIRIS), and their influence on snowmelt timing and magnitude was assessed using a net radiation/temperature index snowmelt model, a series of satellite‐based snow covered area scenes, and on‐site snow surveys. Albedo estimates using an explicit representation of snow surface temperature, snow age, and solar illumination angle, based on the Biosphere Atmosphere Transfer Scheme (BATS), were within the 0.02 AVIRIS measurement error for 78% of the snow‐covered portions of the watershed. Conversely, albedo values estimated using a simple model based solely on snow surface age underestimated AVIRIS‐observed albedo. Correlations between the timing of snowmelt and observed runoff using the BATS albedo model (R2 = 0.69) were significantly better than those using the age‐based approach (R2 = 0.59) and were comparable to using AVIRIS data (R2 = 0.73). Snow extent was simulated most accurately with the AVIRIS parameterization; average map accuracy was 79 and 10% greater than when using the age‐based and BATS albedo parameterizations, respectively. The error in snow water equivalent for April was 14% for BATS versus 39% for the age‐based albedo; however, it was less than 1% for simulations using AVIRIS albedo data. Thus the BATS albedo estimates performed better than the age‐based albedo but did not outperform simulations using AVIRIS albedo data.
Space-charge-limited flows in the quantum regime
Authors: Ang L. K. , Koh W. S. , Lau Y. Y. , Kwan T. J. T.
Published: May 2006

This paper reviews the recent developments of space-charge-limited (SCL) flow or Child-Langmuir (CL) law in the quantum regime. According to the classical CL law for planar diodes, the current density scales as 3∕2’s power of gap voltage and to the inverse squared power of gap spacing. When the electron de Broglie wavelength is comparable or larger than the gap spacing, the classical SCL current density is enhanced by a large factor due to electron tunneling and exchange-correlation effects, and there is a new quantum scaling for the current density, which is proportional to the 1∕2’s power of gap voltage, and to the inverse fourth-power of gap spacing. It is also found that the classical concepts of the SCL flow such as bipolar flow, transit time, beam-loaded capacitance, emitted charge density, and magnetic insulation are no longer valid in quantum regime. In the quantum regime, there exists a minimum transit time of the SCL flows, in contrast to the classical solution. By including the surface properties of the emitting surface, there is a threshold voltage that is required to obtain the quantum CL law. The implications of the Fowler-Nordheim-like field emission in the presence of intense space charge over the nanometer scale is discussed.
Magnetohydrodynamic dynamo in reversed field pinch plasmas: Electrostatic drift nature of the dynamo velocity field
Authors: Cappello S. , Bonfiglio D. , Escande D. F.
Published: May 2006

Within the framework of magnetohydrodynamic (MHD) numerical modeling, the reversed field pinch (RFP) has been found to develop turbulent or laminar regimes switching from the former to the latter in a continuous way when the strength of dissipative forces increases. The laminar solution corresponds to a simple global helical deformation of the current channel and is associated with an electrostatic dynamo field. The related electrostatic drift yields the main component of the dynamo velocity field. While quite natural in the stationary helical state, this analysis is shown to extend also to the dynamic turbulent regime for an Ohmic RFP. The continuity of the transition between the two regimes suggests that the simple helical symmetric solution can provide a fruitful intuitive description of the RFP dynamo in general. Many of the MHD predictions are in good agreement with experimental findings.
Excited states in the multireference state-specific coupled-cluster theory with the complete active space reference
Authors: Ivanov Vladimir V. , Adamowicz Ludwik , Lyakh Dmitry I.
Published: May 2006

The recently proposed multireference state-specific coupled-cluster theory with the complete active space reference has been used to study electronically excited states with different spatial and spin symmetries. The algorithm for the method has been obtained using the computerized approach for automatic generation of coupled-cluster diagrams with an arbitrary level of the electronic excitation from a formal reference determinant. The formal reference is also used to generate the genuine reference state in the form of a linear combination of determinants contracted to a configuration with the spin and spatial symmetries of the target state. The natural-orbital expansions of the one-electron configuration inferaction density matrix allowed us to obtain the most compact orbital space for the expansion of the reference function. We applied our approach in the calculations of singlet and triplet states of different spatial symmetries of the water molecule. The comparisons of the results with values obtained using other many-particle methods and with the full configuration interaction results demonstrate good ability of the approach to deal with electronic excited states.
Unified treatment and classification of superintegrable systems with integrals quadratic in momenta on a two-dimensional manifold
Authors: Daskaloyannis C. , Ypsilantis K.
Published: May 2006

In this paper we prove that the two-dimensional superintegrable systems with quadratic integrals of motion on a manifold can be classified by using the Poisson algebra of the integrals of motion. There are six general fundamental classes of superintegrable systems. Analytic formulas for the involved integrals are calculated in all the cases. All the known superintegrable systems are classified as special cases of these six general classes.
Converged vibrational energy levels and quantum mechanical vibrational partition function of ethane
Authors: Chakraborty Arindam , Truhlar Donald G.
Published: May 2006

The vibrational partition function of ethane is calculated in the temperature range of 200–600K using well-converged energy levels that were calculated by vibrational configuration interaction, and the results are compared to the harmonic oscillator partition function. This provides the first test of the harmonic oscillator approximation for a molecule with more than five atoms. The absolute free energies computed by the harmonic oscillator approximation are in error by 0.59–0.62kcal∕mol over the 200–600K temperature range.
Characterization of a charge-coupled device array for Bragg spectroscopy
Authors: Indelicato Paul , Le Bigot Eric-Olivier , Trassinelli Martino , Gotta Detlev , Hennebach Maik , Nelms Nick , David Christian , Simons Leopold M.
Published: May 2006

The average pixel distance as well as the relative orientation of an array of six charge-coupled device (CCD) detectors have been measured with accuracies of about 0.5nm and 50μrad, respectively. Such a precision satisfies the needs of modern crystal spectroscopy experiments in the field of exotic atoms and highly charged ions. Two different measurements have been performed by illuminating masks in front of the detector array by remote sources of radiation. In one case, an aluminum mask was irradiated with x rays, and in a second attempt, a nanometric quartz wafer was illuminated by a light bulb. Both methods gave consistent results with a smaller error for the optical method. In addition, the thermal expansion of the CCD detectors was characterized between −105 and −40°C.
A molecular-beam optical Stark study of lines in the (1,0) band of the FΔ7∕24-XΔ7∕24 transition of iron monohydride, FeH
Authors: Steimle Timothy C. , Chen Jinhai , Harrison Jeremy J. , Brown John M.
Published: May 2006

A supersonic molecular beam of iron monohydride, FeH, has been generated using a laser ablation/chemical reaction scheme and probed at near-natural linewidth resolution by optical Stark spectroscopy utilizing laser-induced fluorescence detection. The observed Stark splitting in Q(3.5) and R(3.5) lines of the FΔ7∕24←XΔ7∕24 (1,0) transition were analyzed to determine values for the magnitudes of the permanent electric dipole moments, ∣μ∣, which were found to be 2.63(3) and 1.29(3)D for the XΔ4 (v=0) and FΔ4 (v=1) states, respectively. A comparison with ab initio theoretical predictions is made. The Λ doubling in the low-J levels of the FΔ7∕24 (v=1) state is also modeled.
Laser emission at 0.8μm from photopumped luminescent polymer microresonators
Authors: Kobayashi Takeyuki , Djiango Martin , Jordan Grace , Rüther Manuel , Blau Werner J. , Suzuki Yasuhiro , Kaino Toshikuni
Published: May 2006

We present the results of a study on laser emission from luminescent polymer microresonators containing a near-infrared emitting dye, 2-(6-(4-dimethylaminophenyl)-2,4-neopentylene-1,3,5-hexatrienyl)-3-methyl-benzothiazolium perchlorat. Poly(1-vinyl-2-pyrrolidone) microrings doped with the dye are fabricated around a 200-μm-diameter silica optical fiber by self-assembly and are shown to lase at around 835nm under nanosecond photopumping at 532nm. The threshold for lasing is found to be 311±87μJ∕cm2 (62.2±17.3kW∕cm2). The lower limit of the cavity quality factor is estimated to be 1.8×103.
Fast coherent all-optical flip-flop memory
Authors: Oksanen Jani , Tulkki Jukka
Published: May 2006

Coherent nonlinear feedback is shown to eliminate the most critical transient problems in the known active integrated all-optical flip-flop structures, potentially increasing the operating speed by an order of magnitude. The nonlinearity is based on the interference of two coherent optical fields and on operating the pertinent laser amplifiers only above the laser threshold. Therefore the lasers have an approximately constant carrier density and an ever present photon population in the laser mode. This enables fast switching. Numerical analysis based on coupled rate equations demonstrates switching times below 25ps (40GHz).
Solid state dendrite formation in an amorphous magnetic Fe77.5Si13.5B9 alloy observed by in situ hot stage transmission electron microscopy
Authors: Ramanujan R. V. , Zhang Y. R.
Published: May 2006

Crystallization of an initially amorphous Fe77.5Si13.5B9 melt spun alloy was studied by in situ hot stage transmission electron microscopy. The morphology of the crystal was initially equiaxed, followed by a morphological transition to an unusual solid state dendrite morphology. This morphological transition is generally observed after the crystal size reaches a critical value of about 45nm. The experimental results of dendrite growth and the morphological transition are compared to theoretical predictions.
Selective and reversible control of a chemical reaction with narrow-band infrared radiation: HXeCC radical in solid xenon
Authors: Khriachtchev Leonid , Tanskanen Hanna , Räsänen Markku
Published: May 2006

The light-induced H+XeC2↔HXeCC reaction is studied in solid Xe, and the full optical control of this reaction is demonstrated. By narrow-band excitation in the IR spectral region, HXeCC radicals can be decomposed to a local metastable configuration and then selectively recovered by resonant excitation of the XeC2 vibrations. The novel recovery process is explained by short-range mobility of the reagents promoted by vibrational energy redistribution near the absorbing XeC2 molecule. This means that a chemical reaction can be selectively promoted in a desired place where the chosen absorber locates. The obtained results make a strong case of solid-state reactive vibrational excitation spectroscopy of weak radiationless transitions.
Quantitative characterization of periodically poled lithium niobate by electrically induced Bragg diffraction
Authors: Kösters M. , Hartwig U. , Woike Th. , Buse K. , Sturman B.
Published: May 2006

By applying strong electric fields, up to 3kV∕mm, to periodically poled lithium niobate (PPLN) and measuring the characteristics of Bragg diffraction from the periodic domain structure, we have determined the basic parameters of PPLN, such as the period length, the duty-cycle ratio, the internal field, and the in-wall refractive index changes. We thus propose a nondestructive optical method for the characterization of periodically poled ferroelectrics.
Effect of defoliation management, based on leaf stage, on perennial ryegrass (Lolium perenne L.), prairie grass (Bromus willdenowii Kunth.) and cocksfoot (Dactylis glomerata L.) under dryland conditions. 1. Regrowth, tillering and water‐soluble carbohydrate concentration
Authors: Turner L. R. , Donaghy D. J. , Lane P. A. , Rawnsley R. P.
Published: May 2006

A field study was undertaken between April 2003 and May 2004 in southern Tasmania, Australia to quantify and compare changes in herbage productivity and water‐soluble carbohydrate (WSC) concentration of perennial ryegrass (Lolium perenne L.), prairie grass (Bromus willdenowii Kunth.) and cocksfoot (Dactylis glomerata L.) under a defoliation regime based on leaf regrowth stage. Defoliation interval was based on the time taken for two, three or four leaves per tiller to fully expand. Dry‐matter (DM) production and botanical composition were measured at every defoliation event; plant density, DM production per tiller, tiller numbers per plant and WSC concentration were measured bimonthly; and tiller initiation and death rates were monitored every 3 weeks. Species and defoliation interval had a significant effect (P < 0·05) on seasonal DM production. Prairie grass produced significantly more (P < 0·001) DM than cocksfoot and ryegrass (5·7 vs. 4·1 and 4·3 t DM ha−1 respectively). Plants defoliated at the two‐leaf stage of regrowth produced significantly less DM than plants defoliated at the three‐ and four‐leaf stages, irrespective of species. Defoliation interval had no effect on plant persistence of any species during the first year of establishment, as measured by plant density and tiller number. However, more frequent defoliation was detrimental to the productivity of all species, most likely because of decreased WSC reserves. Results from this study confirmed that to maximize rates of regrowth, the recommended defoliation interval for prairie grass and cocksfoot is the four‐leaf stage, and for perennial ryegrass between the two and three‐leaf stages.
Is outdoor air pollution associated with physician visits for allergic rhinitis among the elderly in Toronto, Canada?
Authors: Villeneuve P. J. , Doiron M.‐S. , Stieb D. , Dales R. , Burnett R. T. , Dugandzic R.
Published: May 2006

Background:  While a number of studies suggest that air pollution is associated with allergic rhinitis in children, findings among adults have been equivocal. The aim of this study was to examine the relationship between outdoor air pollution and physician visits for allergic rhinitis among individuals ≥65 years of age in Toronto, Canada.

Methods:  Physician visits were identified by using data from the Ontario provincial health insurance plan that is made available to all residents. Our analyses are based on 52 691 physician visits for allergic rhinitis among individuals ≥65 years of age in the Toronto metropolitan area between 1995 and 2000. Generalized linear models were used to regress daily counts of physician visits against daily measures of gaseous and particulate components of air pollution after controlling for seasonality, potential confounders (temperature, relative humidity, aeroallergens), overdispersion and serial correlation.

Results:  A large number of comparisons were undertaken, with most showing no statistically significant associations between daily levels of air pollution and the number of physician visits for rhinitis. In contrast, an interquartile increase in the 10‐day average of ragweed particles increased the mean number of daily rhinitis consultations by 6.4% (95% CI = 0.7–12.4%).

Conclusions:  Our findings suggest that outdoor air pollution is a poor predictor of physician visits for allergic rhinitis among the elderly.
Evaluation of the Sexual Assessment Monitor, a diagnostic device used to electronically quantify ejaculatory latency time: findings from three studies
Authors: DINSMORE WALLACE W. , RALPH DAVID J. , KELL PHILLIP , WYLIE KEVAN R. , DEAN JOHN P. , NOVAK CLAIRE , WYLLIE JENNIFER S. , WYLLIE MICHAEL G.
Published: May 2006

Associate Editor

Michael G. Wyllie

Editorial Board

Ian Eardley, UK

Jean Fourcroy, USA

Sidney Glina, Brazil

Julia Heiman, USA

Chris McMahon, Australia

Bob Millar, UK

Alvaro Morales, Canada

Michael Perelman, USA

Marcel Waldinger, Netherlands

OBJECTIVE

To validate the Sexual Assessment Monitor (SAM), a novel apparatus designed to collect electronic data on ejaculatory latency time (ELT) for diagnosing premature ejaculation (PE), and for accurately measuring treatment outcomes in clinical trials.

PATIENTS, SUBJECTS AND METHODS

Men with PE, and healthy volunteers aged 18–75 years, were enrolled in three open‐label studies, conducted in the UK. The SAM, which consists of a control box with two front attachments, a vibrator and sensor, was attached to the penis. The vibrator, which provides stimulation, was positioned at the frenulum using a soft cuff; the vibrator intensity was set at 80 units for most subjects. The sensor is an indium‐gallium elasticated loop, which was positioned around the base of the penis to detect ejaculatory pulses. These pulses were transmitted to a data recorder in the control box. The data, which are displayed graphically as traces, were automatically classified by a computer‐generated algorithm to quantify ELT.

RESULTS

In all, 53 healthy volunteers and 58 men with PE provided 213 and 195 evaluable records, respectively. Most were complete records (99% and 96%). The pooled data showed that the ELT was much higher for healthy volunteers than for men with PE (geometric means: 687 vs 169 s, respectively), with a healthy volunteer to PE patient ratio of 2.87 (P < 0.001). Only 6.3% of subjects reported mild adverse events, which were unrelated to the SAM.

CONCLUSIONS

These open‐label studies show that the SAM can consistently and safely measure times to erection (from the start of vibration) and ejaculation, and ELT in healthy volunteers and men with PE. These findings show that the SAM has the potential to become the ‘gold standard’ in the diagnosis of PE and in clinical trials design.
How Mafias Migrate: The Case of the `Ndrangheta in Northern Italy
Authors: Varese Federico
Published: May 2006

What are the conditions conducive to long-term transplantation of mafia groups in new territories? This article systematically reviews a number of factors that facilitate such an outcome and then explores two attempts at transplantation by members of the Calabria-based mafia group `Ndrangheta to the town of Bardonecchia (Piedmont region) and to Verona (Veneto region). While the former case was successful, the latter failed. The article concludes that features of the local economy—the presence of significant sectors of the economy unprotected by the state and a local rather than export orientation—generate a demand for criminal protection, and successful transplantation occurs in the presence of such a demand. Generalized migration or forced resettlement of mafiosi are not sufficient to predict transplantation. The article shows that a high level of interpersonal trust among local law-abiding residents is not sufficient to hinder mafia transplantation, contrary to established theories of social capital and trust.
The Effect of the Fiber Curvature Gradient on Break Excitation in Cardiac Tissue
Authors: BEAUDOIN DEBORAH LANGRILL , ROTH BRADLEY J.
Published: May 2006

Background:Break excitation has been hypothesized as a mechanism for the initiation of reentry in cardiac tissue. One way break excitation can occur is by virtual electrodes formed due to a curving fiber geometry. In this article, we are concerned with the relationship between the peak gradient of fiber curvature and the threshold for break stimulation and the initiation of reentry.

Methods: We calculate the maximum gradient of fiber curvature for different scales of fiber geometry in a constant tissue size (20 × 20 mm), and also examine the mechanisms by which reentry initiation fails.

Results: For small peak gradients, reentry fails because break excitation does not occur. For larger peak gradients, reentry fails because break excitation fails to develop into full‐scale reentry. For strong stimuli above the upper limit of vulnerability, reentry fails because the break excitation propagates through the hyperpolarized region and then encounters refractory tissue, causing the wave front to die.
Acute aortic syndrome: pathology and therapeutic strategies
Authors: Ahmad F , Cheshire N , Hamady M
Published: May 2006

Acute aortic syndrome (AAS) describes the acute presentation of patients with characteristic “aortic pain” caused by one of several life threatening thoracic aortic pathologies. These include aortic dissection, intramural haematoma, penetrating atherosclerotic ulcer, aneurysmal leak, and traumatic transection. AAS heralds imminent aortic rupture. Highlighting acute aortic pathology as an AAS is therefore important to encourage prompt recognition of this condition and avoid diagnostic delays. The management of AAS remains a therapeutic challenge. The traditional surgical approach to acute “type B” (descending thoracic) aortic pathology is unsatisfactory with high morbidity and mortality. Endovascular aortic stent grafts now represent an alternative minimally invasive approach in these patients who are often poor surgical candidates. Studies show endovascular repair to be technically feasible with fewer complications. This review discusses AAS pathology and in particular assesses the current role for endovascular aortic repair in its treatment.
RARE DECAYS AND CP VIOLATION BEYOND THE STANDARD MODEL
Authors: SILVESTRINI LUCA
Published: May 2006

We review the status of rare decays and CP violation in extensions of the Standard Model. We analyze the determination of the unitarity triangle and the model-independent constraints on new physics that can be derived from this analysis. We find stringent bounds on new contributions to [Formula: see text] and [Formula: see text] mixing, pointing either to models of minimal flavour violation or to models with new sources of flavour and CP violation in b → s transitions. We discuss the status of the universal unitarity triangle in minimal flavour violation, and study rare decays in this class of models. We then turn to supersymmetric models with nontrivial mixing between second and third generation squarks, discuss the present constraints on this mixing and analyze the possible effects on CP violation in b → s nonleptonic decays and on [Formula: see text] mixing. We conclude presenting an outlook on Lepton-Photon 2009.
REVIEW OF SOLAR AND REACTOR NEUTRINOS
Authors: POON ALAN W. P.
Published: May 2006

Over the last several years, experiments have conclusively demonstrated that neutrinos are massive and that they mix. There is now direct evidence for νe s from the Sun transforming into other active flavors while en route to the Earth. The disappearance of reactor [Formula: see text], predicted under the assumption of neutrino oscillation, has also been observed. In this paper, recent results from solar and reactor neutrino experiments and their implications are reviewed. In addition, some of the future experimental endeavors in solar and reactor neutrinos are presented.
CLASSIFICATION OF CIRRHOSIS FROM B-SCAN IMAGES USING PYRAMID NEURAL NETWORK
Authors: SUN YAN , LU JIANMING , YAHAGI TAKASHI
Published: May 2006

This paper proposes a system applying a pyramid neural network for classifying the hepatic parenchymal diseases in ultrasonic B-scan texture. The conventional multilayer neural network emphasizing on the data carried by the last hidden layer has the drawback of not fully utilizing the information carried by the input data. A pyramid network can solve the problem successfully.

To solve the common problem of neural network, which is time-consuming in computation, FDWT (Fast Discrete Wavelet Transform) is a key technique used during preprocessing to cut down the size of patterns feed to the network. The B-scan patterns are wavelet transformed, and then the compressed data is fed into a pyramid neural network to diagnose the type of cirrhotic diseases.

The performance of the proposed system and that of a system based on the conventional multilayer network architecture is compared. The result shows that compared to the conventional 3-layer neural network, the performance of the proposed pyramid neural network is improved by effectively utilizing the lower layer of the neural network.
The link between cardiac autonomic activity and sleep delta power is altered in men with sleep apnea-hypopnea syndrome
Authors: Jurysta F. , Lanquart J.-P. , van de Borne P. , Migeotte P.-F. , Dumont M. , Degaute J.-P. , Linkowski P.
Published: May 2006

We hypothesize that sleep apnea-hypopnea alters interaction between cardiac vagal modulation and sleep delta EEG. Sleep apnea-hypopnea syndrome (SAHS) is related to cardiovascular complications in men. SAHS patients show higher sympathetic activity than normal subjects. In healthy men, non-rapid eye movement (NREM) sleep is associated with cardiac vagal influence, whereas rapid eye movement (REM) sleep is linked to cardiac sympathetic activity. Interaction between cardiac autonomic modulation and delta sleep EEG is not altered across a life span nor is the delay between appearances of modifications in both signals. Healthy controls, moderate SAHS, and severe SAHS patients were compared across the first three NREM-REM cycles. Spectral analysis was applied to ECG and EEG signals. High frequency (HF) and low frequency (LF) of heart rate variability (HRV), ratio of LF/HF, and normalized (nu) delta power were obtained. A coherency analysis between HFnu and delta was performed, as well as a correlation analysis between obstructive apnea index (AI) or hypopnea index (HI) and gain, coherence, or phase shift. HRV components were similar between groups. In each group, HFnu was larger during NREM, while LFnu predominated across REM and wake stages. Coherence and gain between HFnu and delta decreased from controls to severe SAHS patients. In SAHS patients, the delay between modifications in HFnu and delta did not differ from zero. AI and HI correlated negatively with coherence, while HI correlated negatively with gain only. Apneas-hypopneas affect the link between cardiac sympathetic and vagal modulation and delta EEG demonstrated by the loss of cardiac autonomic activity fluctuations across shifts in sleep stages. Obstructive apneas and hypopneas alter the interaction between both signals differently.
Effects of Neonatal Resveratrol Exposure on Adult Male and Female Reproductive Physiology and Behavior
Authors: Henry Lisa A. , Witt Diane M.
Published: May 2006

Resveratrol (RES) is a phytoestrogen that has the ability to bind to estrogen receptors (ERs) and evoke biological effects that parallel those exerted by endogenous and synthetic estrogens. We have shown in previous studies that adult female rats acutely exposed to RES exhibit estrous cycle irregularity, ovarian hypertrophy, and alterations in sociosexual behavior. The present experiment characterizes the prolonged effects of maternal RES exposure throughout the lactational period on subsequent behavior, reproductive tissues, and brain morphology of the adult offspring. During adulthood, female offspring exposed to RES throughout nursing exhibited reduced body weight and increased ovarian weight, but exhibited normal estrous cyclicity and sociosexual behavior, without changes in the volume of the sexually dimorphic nucleus of the preoptic area or the anteroventral periventricular nucleus of the hypothalamus. During adulthood, males exposed to RES throughout nursing exhibited decreased body weight and plasma testosterone concentration, increased testicular weight, and reduced sociosexual behavior. These males also had significantly smaller sexually dimorphic nucleus of the preoptic area volumes and larger anteroventral periventricular nucleus volumes compared to male controls. These data suggest that postnatal exposure to RES may affect estrogenic activity in specific peripheral tissues (e.g., the gonads), while inducing antiestrogenic effects in the brain. Thus, the present study supports recent in vitro and in vivo findings that RES differs from most other phytoestrogens by acting as a possible mixed ER agonist/antagonist, depending on the tissue-specific availability of ER subtypes that are preferentially localized in specific brain regions and throughout the reproductive tract. More importantly these data indicate that maternal consumption of phytoestrogens during lactation can have lasting effects on the offspring that may not become apparent until they reach adulthood.