bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitation of Sterols and Steryl Esters in Fortified Foods and Beverages by GC/FID
Authors: Clement Lisa M. , Hansen Steven L. , Costin Colin D. , Perri Gregg L.
Published: April 2010

Direct extraction methods for the quantitation of sterols and steryl esters (SE) in foods, beverages and concentrates as free sterols (trimethylsilane ether derivatives) by gas chromatography with flame ionization detection (GC/FID) are introduced. Theoretical correction factors are used for sterol quantification relative to the internal standard, Epicoprostanol. Conversion of the acylglycerols, when present, into FFA eliminates the time‐consuming acylglycerol extraction step and reduces the GC run time since no higher molecular weight acylglycerols need to elute from the column. Accuracy and precision of analytical data are important when formulating food products with sterols or SE to ensure a formulation will meet health claims, while at the same time minimizing costly over formulation. Method accuracy was determined by complete recovery of sterol and SE concentrates as free sterols with subsequent analysis of foods and beverages formulated with sterol and SE concentrates. Triplicate analysis over 5 days demonstrated repeatability for the alkaline saponification and acid extraction with alkaline saponification methods. A relative standard deviation of <5% demonstrates the repeatability of the methods. Replicate analysis of a common sample by two laboratories and replicate analysis of a common sample by multiple analysts demonstrated reproducibility of the methods.
Genistein as a neuroprotective antioxidant attenuates redox imbalance induced by β‐amyloid peptides 25–35 in PC12 cells
Authors: Ma Weiwei , Yuan Linhong , Yu Huanling , Ding Bingjie , Xi Yuandi , Feng Jinfang , Xiao Rong
Published: April 2010

Objective

Genistein (GEN), a principal component of soybean isoflavones, might possess the neuroprotective role through its antioxidant activity. However, the detailed mechanisms are unknown yet. The purpose of this study was to investigate whether GEN could alleviate oxidative damage induced by β‐amyloid peptides 25–35 (Aβ25–35) in PC12 cells.

Methods

The PC12 cells were pre‐incubated with or without GEN for 2 h following incubation with Aβ25–35 for another 24 h. MTT was used to assess the cell viability. Hoechst 33342 staining was applied to determine the apoptotic cells. Confocal laser scanning microscopy was implemented to examine the reactive oxygen species (ROS) levels. Mitochondrial membrane potential (MMP) was measured by flow cytometry. Reduced and oxidized glutathione (GSH/GSSG) ratio was analyzed by using assay kits. Western blot analysis was performed to assess the proteins expression of NF‐E2‐related factor 2 (Nrf2), heme oxygenase‐1 (HO‐1) and γ‐glutamylcysteine synthetase (γ‐GCS).

Results

GEN attenuated the cytotoxicity and partially prevented apoptosis induced by Aβ25–35. GEN dramatically attenuated ROS levels induced by Aβ25–35 in PC12 cells. In addition, GEN significantly reversed the reduction of MMP caused by Aβ25–35 to maintain the normal levels of the cells. The GSH/GSSG ratio in GEN pretreated groups significantly increased compared to the groups without GEN pretreatment. GEN reversed Aβ25–35 induced down regulation of the protein expression of γ‐GCS, Nrf2 and HO‐1.

Conclusion

GEN could alleviate the oxidative stress caused by Aβ25–35 treatment and maintain redox balance in PC12 cells, which might be associated with the regulation of Nrf2/HO‐1 signal pathway.
Risk factors for vaginal prolapse after hysterectomy
Authors: Lukanovič Adolf , Dražič Katarina
Published: April 2010

Objective

To identify risk factors for pelvic organ prolapse (POP) and their influence on the occurrence of vaginal prolapse after hysterectomy.

Methods

Medical records from 2 groups of women who had undergone hysterectomy were reviewed retrospectively. The study group was 82 women who had undergone surgery for vaginal prolapse after hysterectomy; the control group was 124 women who had undergone hysterectomy with no diagnosis of vaginal prolapse by the time of the study. All hysterectomy procedures had been performed for benign gynecological disease, including POP. Both groups of women completed a self‐administered questionnaire to obtain additional information on the occurrence of POP.

Results

The incidence of vaginal prolapse after hysterectomy was significantly higher in women with a higher number of vaginal deliveries, more difficult deliveries, fewer cesareans, complications after hysterectomy, heavy physical work, neurological disease, hysterectomy for pelvic organ prolapse, and/or a family history of pelvic organ prolapse. Premenopausal women had vaginal prolapse corrected an average of 16 years after hysterectomy, and postmenopausal women 7 years post hysterectomy.

Conclusion

Before deciding on hysterectomy as the approach to treat a woman with pelvic floor dysfunction, the surgeon should evaluate these risk factors and discuss them with the patient.
A Microfluidic System for Biological Particle Enrichment Using Contactless Dielectrophoresis
Authors: Shafiee Hadi , Caldwell John L. , Davalos Rafael V.
Published: April 2010

A microfluidic system for the enrichment of biological particles, operating on the principle of dielectrophoresis (DEP), is presented. Through the use of a unique manifestation of DEP, contactless DEP (cDEP), this system illustrates the potential to sidestep the common trade-off between sample throughput and selectivity without the need of a complicated fabrication process. The ability to concentrate particles from a sample fluid is validated experimentally through the concentration of 2-μm polystyrene beads and live THP-1 human leukemia cells from a heterogeneous media solution. Finite element analysis of the electric field within the microfluidic channel of the device allows for the determination of effective experimental parameters and accurate predictions of a particle's trajectory through the device. The concentration of particles combined with a fabrication procedure conducive to mass production makes cDEP an attractive alternative to current sample enrichment technologies.
Evaluating local implementation: An evidence-based approach
Authors: Wond Tracey , Macaulay Michael
Published: April 2010

This article, based on data collected from a year-long study, investigates the evaluation of a UK local government policy implementation and the use of evaluation data as an evidence-base for public policy (Bovaird & Loeffler, 2007; McCoy & Hargie, 2001; Schofield, 2004; Stern, 2008). Our case study highlights a number of issues. First, uncertainty and ambiguity of policy direction inhibiting the establishment of clear evaluation goals, which, second, results in frustration among stakeholders at a perceived disparity between what we term problem-inspired policy and problem-solving policy. Finally, this perception can be compounded by a lack of consideration for local variations of, for example, specific cultures, geographies or historical contexts. In responding to these problems our article argues that regardless of where policy control and decision-making occurs, the importance of the experiences of policy-implementers at a local level (where subject/geographical/cultural specialism and familiarisation exists) is crucial.
Climatology of the Eastern Arabian Sea during the last glacial Cycle reconstructed from paired measurement of foraminiferal δ18O and Mg/Ca
Authors: Banakar V.K. , Mahesh B.S. , Burr G. , Chodankar A.R.
Published: April 2010

Paired measurements of Mg/Ca and δ18O of Globigerenoides sacculifer from an Eastern Arabian Sea (EAS) sediment core indicate that sea-surface temperature (SST) varied within 2°C and sea-surface salinity within 2 psu during the last 100 ka. SST was coldest (∽ 27°C) during Marine Isotope Stage (MIS) 4 and 2. Sea-surface salinity was highest (∽ 37.5 psu) during most of the last glacial period (∽ 60–18 ka), concurrent with increased δ18O G.sacculifer and C/N ratios of organic matter and indicative of sustained intense winter monsoons. SST time series are influenced by both Greenland and Antarctic climates. However, the sea-surface salinity time series and the deglacial warming in the SST record (beginning at ∽18 ka) compare well with the LR04 benthic δ18O-stack and Antarctic temperatures. This suggests a teleconnection between the climate in the Southern Hemisphere and the EAS. Therefore, the last 100-ka variability in EAS climatology appears to have evolved in response to a combination of global climatic forcings and regional monsoons. The most intense summer monsoons within the Holocene occurred at ∽8 ka and are marked by SST cooling of ∽ 1°C, sea-surface salinity decrease of 0.5 psu, and δ18O G.sacculifer decrease of 0.2‰.
Interplay between detrital and diagenetic processes since the last glacial maximum on the northwest Iberian continental shelf
Authors: Mohamed Kais Jacob , Rey Daniel , Rubio Belen , Vilas Federico , Frederichs Thomas
Published: April 2010

Integrated analyses of magnetic, geochemical and textural data on six cores from the northwestern Iberian continental shelf allowed the reconstruction of the paleoenvironmental evolution of this area since the last glacial maximum (LGM). Four sedimentary units were identified, representing a succession from fluvial and subaerial settings to high and finally low-energy marine deposits subsequent to the post-LGM sea-level rise. The uppermost unit was deposited during the Holocene and its magnetic properties were controlled by the interplay between detrital input and early diagenetic reductive dissolution of magnetic minerals. Identification of a primary steady-state early diagenetic signal allowed the recognition of periods of increased detrital input, bounded by intervals of lower detrital input and intensified reductive diagenesis related to intensified upwelling in the area. These paleoenvironmental alternations are consistent with the climatic evolution of the late Holocene. During the Roman Warm Period and Medieval Warm Period, the combined effect of greater humidity and intense agricultural and mining activities led to a greater erosion and transport of detrital sediments to the shelf. In contrast, enhanced diagenetic reduction intervals, caused by upwelling intensification, were roughly coincident with the colder Dark Ages and the Little Ice Age.
Angehörige auf Intensivstationen: Auswirkungen und Bewältigung. Eine Literaturübersicht über qualitative Forschungsarbeiten
Authors: Nagl-Cupal Martin , Schnepp Wilfried
Published: April 2010

Wenn ein Mensch auf eine Intensivstation eingeliefert wird, ist nicht nur er selbst, sondern die ganze Familie von diesem Ereignis betroffen. Um einen tieferen Einblick in die Situation Angehöriger auf Intensivstationen zu erhalten, wird in dieser Literaturstudie anhand qualitativ durchgeführter Forschungsarbeiten aufgezeigt, welche Auswirkungen es auf die Betroffenen hat, wenn eines ihrer Familienmitglieder auf der Intensivstation liegt und wie sie mit dieser Situation umgehen. Es wurden 15 Studien analysiert. Die Situation ist gekennzeichnet durch Unsicherheit, überwältigende Emotionen, das Übernehmen von zusätzlichen Verantwortlichkeiten und das Ausfüllen divergierender Rollen. Dabei zeigt sich, dass Angehörige stets das kranke Familienmitglied in den Vordergrund stellen, die eigene Person wird während dieser Zeit hinten angereiht. Um mit der Situation umzugehen, kommen verschiedene Mechanismen und Strategien zum Tragen. Zentral dabei ist, dass Angehörige ihrem kranken Familienmitglied stets nahe sein wollen, mit oder auch ohne Integration in die Pflege. Sie suchen ehrliche Informationen, erhalten soziale Unterstützung und versuchen, stets die Hoffnung zu bewahren. Der Beitrag geht des Weiteren auf Grenzen und Übertragbarkeit der Arbeiten ein.
Die Lebenssituationen Parkinsonbetroffener und deren Angehörigen im Spiegel der Literatur – ein Überblick
Authors: Mai Tobias , Schnepp Wilfried , Höhmann Ulrike
Published: April 2010

Trotz neuer Therapieformen gibt es derzeit keine Aussicht auf Heilung oder Stillstand der Parkinsonerkrankung. Deshalb und wegen des prognostizierten Wachstums der Anzahl der Parkinsonbetroffenen wird neben der medizinischen auch die pflegerische Versorgung der Betroffenen in Zukunft von größerer Bedeutung sein. Die durchgeführte Literaturrecherche hatte zum Ziel, die in der Fachliteratur beschriebenen Situationen der Parkinsonbetroffenen und deren Angehörigen zu untersuchen, um an diesen Beschreibungen die spezialisierte Pflege in Deutschland zu diskutieren. Die systematische Suche wurde in den Datenbanken PubMed, CINAHL, Embase und Cochrane Library of Systematic Reviews durchgeführt. Die Resultate wurden in erster Linie im Hinblick auf zwei der zentralen Merkmale einer ­sozialen Situation nach Dreitzel (1972) – den inhaltlichen Themen und den Interaktionspartnern – betrachtet. Die Themen wurden anhand der Bewältigungsanforderungen dargestellt, die nach Corbin und Strauss (2004) im Laufe einer chronischen Krankheit auftreten. Die Ergebnisse der Recherche von 41 Studien und Übersichtsartikeln zeigen auf Basis der zentralen Bewältigungsanforderungen der Betroffenen in unterschiedlichen Lebenssituationen die Notwendigkeit einer kontinuierlichen Begleitung von Menschen mit Parkinsonsyndromen und deren Angehörigen. Dabei geht es um zentrale Themen wie finanzielle Absicherung, Aufrechterhaltung der eigenen Rolle, Unterstützung im Umgang mit der Diagnose bekommen und Akzeptanz von Gesundheitsberufen gegenüber der eigenen körperlichen Symptomwahrnehmung erhalten. Als besonders herausfordernde Lebenssituationen werden das Arbeits- und das Familienleben, Paarbeziehungen, Arzt-Patient- und Pflege-Patient-Beziehungen, Eltern-Kind-Beziehungen sowie Leben in der Gesellschaft beschrieben. Die Bedeutung einer Begleitung durch eine spezialisierte Pflegekraft im Sinne der Parkinson's Disease Nurse Specialists wird diskutiert.
Wie Menschen mit einer Amputation der unteren Extremitäten ihren Alltag erleben und bewältigen
Authors: Möhler Ralph , Schnepp Wilfried
Published: April 2010

Eine Amputation der unteren Extremitäten stellt für die Betroffenen einen starken Einschnitt im Leben dar. Von einem Moment auf den anderen ist ein wesentlicher Teil des Körpers nicht mehr vorhanden und gleichzeitig ist die Gehfähigkeit nicht mehr selbstverständlich. Gefäßschädigende Komplikationen bei Diabetes mellitus zählen zu den häufigsten Ursachen für eine Amputation der unteren Extremitäten. Betroffene, die an dieser chronischen Krankheit leiden, sind in ihrem Alltag bereits besonderen Belastungen und Unsicherheiten ausgesetzt. Was es jedoch bedeutet, mit einer chronischen Krankheit leben zu müssen und zudem noch eine Amputation zu erleben, ist bislang wenig erforscht. Die vorliegende Forschungsarbeit untersucht die Frage, wie Menschen mit einer Amputation der unteren Extremitäten aufgrund einer Gefäßerkrankung ihren Alltag erleben und bewältigen. Zur Bearbeitung dieser Fragestellung wurde ein qualitatives Forschungsdesign nach dem Ansatz der Grounded Theory gewählt. Qualitative Interviews mit neun von einer Amputation betroffenen Menschen wurden geführt und die Auswertung der Daten erfolgte anhand der Methode der Grounded Theory. Die Betroffenen erleben infolge der Amputation einschneidende Verluste: den Verlust eines Körperteils mit Folgen für ihr Körperbild, den Verlust ihrer Mobilität – daraus resultierend eine Abhängigkeit von Hilfsmitteln – und den Verlust von Alltagsfähigkeiten. Sie bewältigen diese Verluste, indem sie sich damit «abfinden». Den Alltag bewältigen sie, indem sie sich bemühen, ihre selbstständige Mobilität wiederzugewinnen, was ihnen gleichzeitig die Möglichkeit eröffnet, jeweils individuell bedeutsame Aktivitäten und Tätigkeiten im Rahmen bestehender Einschränkungen wieder ausführen zu können. Die Ergebnisse dieser Arbeit leisten einen Beitrag dazu, die Herausforderungen des Alltags nach einer Amputation der unteren Extremitäten aufgrund einer gefäßschädigenden Erkrankung verstehen zu können, was als Grundlage für die Begleitung dieser Menschen dienen soll.
Der Diskurs zu den Gütekriterien der qualitativen Forschung
Authors: Haas-Unmüßig Pia , Schmidt Cordula
Published: April 2010

Trotz ihrer Juvenilität weist die pflegewissenschaftliche Forschung im deutschsprachigen Raum eine rasch wachsende Anzahl durchgeführter Studien auf; unter ihnen sind zahlreiche auf qualitativer Methodik basierende Untersuchungen. Mindestens aktuell, wenn nicht dringlich, erscheint vor diesem Hintergrund die Frage, welche Gütekriterien in der Durchführung und Bewertung qualitativer Forschungsarbeiten heranzuziehen sind und wie die derzeitige Scientific Community allgemein und die der Pflegewissenschaft im Besonderen mit der Thematik umgehen. Anhand unterschiedlicher Grundpositionen werden in diesem Aufsatz die vielfältigen, in den Veröffentlichungen der Pflegewissenschaft im deutschsprachigen Raum behandelten Kriterien zur Gütesicherung in Anlehnung an die sozialwissenschaftliche Literatur aufgezeigt. Darüber hinaus werden ergänzende Aspekte der in jüngster Zeit erweiterten Qualitätsdebatte einbezogen. Zur besseren Einschätzung des Diskursstandes in der deutschsprachigen Literatur erfolgt im Anschluss ein Abgleich mit aktuellsten englischsprachigen Journalbeiträgen. Abschließend werden die Ergebnisse diskutiert.
Testtheoretische Gütekriterien des Q-DIO, eines Instruments zur Messung der Qualität der Dokumentation von Pflegediagnosen, -interventionen und -ergebnissen
Authors: Müller-Staub Maria , Lunney Margaret , Lavin Mary Ann , Needham Ian , Odenbreit Matthias , van Achterberg Theo
Published: April 2010

Das Instrument Q-DIO wurde zur Messung der Qualität von dokumentierten Pflegediagnosen, Pflegeinterventionen und pflegesensiblen Patientenergebnissen in den Jahren 2005 bis 2006 entwickelt. Das Ziel dieser Studie war die Prüfung testtheoretischer Eigenschaften von Q-DIO (Quality of Nursing Diagnoses, Interventions and Outcomes). Die Prüfung des Instruments umfasste die interne Konsistenz, Test-Retest-Reliabilität, Interrater-Reliabilität, eine Itemanalyse und die Einschätzung der Objektivität. Um Aussagen zur Variabilität der Messergebnisse zu erhalten, wurde eine geschichtete zufällige Stichprobe von 60 Pflegedokumentationen gewählt. Die Schichten repräsentierten 30 Pflegedokumentation mit und 30 ohne Einführung theoriegeleiteter standardisierter Pflegesprachen. Die Prüfung der internen Konsistenz der Subskala «Pflegediagnosen als Prozess» ergab ein Cronbach's Alpha von 0,83 [0,78; 0,88]; die Subskala «Pflegediagnosen als Produkt» 0,98 [0,94; 0,99]; «Pflegeinterventionen» 0,90 [0,85; 0,94] und «pflegesensible Patientenergebnisse» 0,99 [0,95; 0,99]. Mit einem Kappawert von 0,95 [0,90; 0,97] war die Intrarater-Reliabilität gut. Die Interrater-Reliabilität zeigte einen Kappawert von 0,94 [0,90; 0,96]. Die Itemanalyse bestätigte die Erfüllung der Kriterien zu Schwierigkeitsgrad und Trennschärfe der Items. Damit ermöglicht Q-DIO die zuverlässige Messung der Qualität von dokumentierten Pflegediagnosen, -interventionen und -ergebnissen mit und ohne Einführung von theoriegeleiteten, standardisierten Pflegesprachen. Studien zu weiteren Testungen von Q-DIO in anderen Settings werden empfohlen. Implizit unterstützen die Resultate die Anwendung von Pflegeklassifikationen wie NANDA, NIC und NOC.
Use of POES SEM‐2 observations to examine radiation belt dynamics and energetic electron precipitation into the atmosphere
Authors: Rodger Craig J. , Clilverd Mark A. , Green Janet C. , Lam Mai Mai
Published: April 2010

The coupling of the Van Allen radiation belts to the Earth's atmosphere through precipitating particles is an area of intense scientific interest. Currently, there are significant uncertainties surrounding the precipitating characteristics of medium energy electrons (>20 keV), and even more uncertainties for relativistic electrons. In this paper we examine roughly 10 years of measurements of trapped and precipitating electrons available from the Polar Orbiting Environmental Satellites (POES)/Space Environment Monitor (SEM‐2), which has provided long‐term global data in this energy range. We show that the POES SEM‐2 detectors suffer from some contamination issues that complicate the understanding of the measurements, but that the observations provide insight into the precipitation of energetic electrons from the radiation belts, and may be developed into a useful climatology for medium energy electrons. Electron contamination also allows POES/SEM‐2 to provide unintended observations of >700 keV relativistic electrons. Finally, there is an energy‐dependent time delay observed in the POES/SEM‐2 observations, with the relativistic electron enhancement (electrons >800 keV) delayed by approximately one week relative to the >30 keV electron enhancement, probably due to the timescales of the acceleration processes. Observations of trapped relativistic electron fluxes near the geomagnetic equator by GOES show similar delays, indicating a “coherency” to the radiation belts at high and low orbits, and also a strong link between trapped and precipitating particle fluxes. Such large delays should have consequences for the timing of the atmospheric impact of geomagnetic storms.
Strain localization along the Atlantis Bank oceanic detachment fault system, Southwest Indian Ridge
Authors: Miranda Elena A. , John Barbara E.
Published: April 2010

Microstructural observations and mineral thermometry from in situ samples collected from the Atlantis Bank oceanic core complex (SW Indian Ridge) indicate that detachment faulting was initiated under hypersolidus conditions in the ductile regime and continued through subgreenschist temperatures through the ductile, semibrittle, and brittle regimes as strain localized along the exposed, now subhorizontal fault surface. Ductile, semibrittle, and brittle fabrics are developed within dominantly gabbroic rocks. Footwall rocks exhibit crystal plastic fabrics distributed over a structural thickness up to 400 m below the denuded fault surface exposed at the seafloor, whereas semibrittle and brittle fabrics are concentrated in the 80 and 30 m immediately below the principal slip surface of the detachment fault, respectively. Sample fabrics suggest that strain localization was achieved by dynamic recrystallization of plagioclase at temperatures between 910°C and 650°C, by amphibole‐accommodated dissolution‐precipitation creep at temperatures ∼750°C–450°C, by chlorite‐accommodated reaction softening at temperatures ∼450°C–300°C, and by brittle fracturing and cataclasis at temperatures <300°C.
Woody plant encroachment paradox: Rivers rebound as degraded grasslands convert to woodlands
Authors: Wilcox Bradford P. , Huang Yun
Published: April 2010

The related phenomena of degradation and woody plant encroachment have transformed huge tracts of rangelands. Woody encroachment is assumed to reduce groundwater recharge and streamflow. We analyzed the long‐term (85 years) trends of four major river basins in the Edwards Plateau region of Texas. This region, in which springs are abundant because of the karst geology, has undergone degradation and woody encroachment. We found that, contrary to widespread perceptions, streamflows have not been declining. The contribution of baseflow has doubled—even though woody cover has expanded and rainfall amounts have remained constant. We attribute this increase in springflow to a landscape recovery that has taken place concurrently with woody expansion—a recovery brought about by lower grazing pressure. Our results indicate that for drylands where the geology supports springs, it is degradation and not woody encroachment that leads to regional‐scale declines in groundwater recharge and streamflows.
Features of electron current layers: Comparison between three‐dimensional particle‐in‐cell simulations and Cluster observations
Authors: Singh Nagendra , Yeladandi Manish , Somarothu Trinath , Wells B. E.
Published: April 2010

Wygant et al. (2005) and more recently Chen et al. (2008) reported Cluster observations on some basic features of electron current layers (ECL) in the magnetotail. These features include (1) a bifurcated ECL consisting of two layers with relatively large currents separated by a region of small current, (2) peaked density at the ECL center bordered by extended low‐density regions, (3) bipolar Hall electric fields (EHall), (4) fine‐scale, large‐amplitude spiky turbulence in the electric fields normal to the plane of the ECL (En), (5) energized electrons that become increasingly isotropized toward the ECL central region, (6) cold electrons bordering the ECL, (7) ions accelerated by the Hall electric field, and (8) ions counterstreaming against the ions accelerated by EHall on both the north and south sides of the neutral sheet at the ECL midplane. We compare all these features with results from fully three‐dimensional particle‐in‐cell simulations of an ECL. Simulations reveal that the fine structures in the electric fields inside the ECL are created by the ECL‐driven electrostatic instabilities, which are instrumental in rapid heating and isotropization of the electrons with power law energy distribution, Fe(E) ≈ E−0.7. The heated electrons set up ambipolar electric fields (Ea) in the central part of the ECL, reflecting ions accelerated by EHall. The overall structures in the normal electric fields result from the superposition of EHall, Ea, and the instability‐generated electric fields.
Solar cycle evolution of the solar wind speed distribution from 1985 to 2008
Authors: Tokumaru Munetoshi , Kojima Masayoshi , Fujiki Ken'ichi
Published: April 2010

The evolution of solar wind speed distribution during the period 1985–2008, which covers two solar cycles (22 and 23), has been investigated using multistation interplanetary scintillation (IPS) measurements at 327 MHz. The results obtained here clearly demonstrate that fast (slow) wind areas increase (decrease) systematically as the solar activity diminishes, reaching the maximum (minimum) value at the minimum phase. The intermediate‐speed wind areas appear to remain constant over the solar cycle. The preponderance of slow wind at low latitudes was confirmed from our IPS observations throughout the period, while a slight increase in the fast wind area was revealed in the declining to minimum phases. In contrast, the high‐latitude solar wind was mostly dominated by the fast wind except for a few years around the maxima. An important point to note is the clear difference in the solar wind speed distribution between the 1996 and 2008 minima. The fast wind areas in 2008 showed a marked increase at low latitudes, which is consistent with in situ observations at 1 AU, and a distinct decrease at high latitudes, resulting in a net decrease at all latitudes, as compared with those in 1996. This difference is ascribed to the weaker polar fields during the 2008 minimum. An excellent positive (negative) correlation between fast (slow) wind areas and the polar fields is revealed from a comparison between IPS and magnetograph observations. The results obtained here suggest a strong control of the Sun's polar field in determining the solar wind acceleration and structure.
Global Ultraviolet Imager equatorial plasma bubble imaging and climatology, 2002–2007
Authors: Comberiate Joseph , Paxton Larry J.
Published: April 2010

A comprehensive database of plasma bubble reconstructions is under development, with results reported here from more than 5 years of Global Ultraviolet Imager (GUVI) data. Climatological statistics of plasma bubble occurrence from this database are presented, including the effects of longitudinal, seasonal, geomagnetic, and solar cycle variations on plasma bubble occurrence. The relationship between the latitudinal separation and peak electron density values of the equatorial arcs and plasma bubble occurrence is also discussed. Since its launch on board the Thermosphere Ionosphere Mesosphere Energetics and Dynamics satellite in December 2001, GUVI has more than 7 years of observations of the nightside equatorial ionosphere. GUVI is capable of detecting and imaging plasma bubbles within the northern and southern equatorial arcs. An automated algorithm was developed to locate the peaks of the equatorial arcs and detect the presence of equatorial plasma bubbles. This algorithm was integrated with a tomographic imaging model and a statistical inversion technique to reconstruct electron density and produce multidimensional images of plasma depletion structures.
Seasonal climatology of wind‐driven circulation on the New Jersey Shelf
Authors: Gong D. , Kohut J. T. , Glenn S. M.
Published: April 2010

The spatial structure of the mean and seasonal surface circulation in the central region of the Mid‐Atlantic Bight (New Jersey Shelf) are characterized using 6 years of CODAR long‐range HF radar data (2002–2007). The mean surface flow over the New Jersey Shelf is 2–12 cm/s down shelf and offshore to the south. The detided root‐mean‐square (RMS) velocity variability ranges from 11 to 20 cm/s. The variability is on the order of the mean current offshore and several times that of the mean current nearshore. The Hudson Shelf Valley and the shelf break act as dynamical boundaries that define the New Jersey Shelf. The surface flow on the New Jersey Shelf depends on topography, seasonal stratification, and wind forcing. The flow is in the approximate direction of the wind during the unstratified season and more to the right of the wind during the stratified season. During the stratified summer season, the dominant along‐shore upwelling favorable winds from the SW drive cross‐shelf offshore flow. During the unstratified/well‐mixed winter season, the dominant cross‐shore NW winds drive cross‐shelf offshore flows. During the transition seasons of spring and autumn, along‐shore NE winds, often associated with storm events, drive energetic down‐shelf, along‐shelf flows. The surface transport pathways are either cross‐shelf dominated during summer and winter or along‐shelf dominated during the transition seasons. The residence time of surface Lagrangian drifters on the New Jersey Shelf ranged from 1 to 7 weeks with summer and autumn showing faster transport than winter and spring.
How will sea level respond to changes in natural and anthropogenic forcings by 2100?
Authors: Jevrejeva S. , Moore J. C. , Grinsted A.
Published: April 2010

Using an inverse statistical model we examine potential response in sea level to the changes in natural and anthropogenic forcings by 2100. With six IPCC radiative forcing scenarios we estimate sea level rise of 0.6–1.6 m, with confidence limits of 0.59 m and 1.8 m. Projected impacts of solar and volcanic radiative forcings account only for, at maximum, 5% of total sea level rise, with anthropogenic greenhouse gasses being the dominant forcing. As alternatives to the IPCC projections, even the most intense century of volcanic forcing from the past 1000 years would result in 10–15 cm potential reduction of sea level rise. Stratospheric injections of SO2 equivalent to a Pinatubo eruption every 4 years would effectively just delay sea level rise by 12–20 years. A 21st century with the lowest level of solar irradiance over the last 9300 years results in negligible difference to sea level rise.
Providing Augmentative and Alternative Communication Treatment to Persons With Progressive Nonfluent Aphasia
Authors: Fried-Oken Melanie , Rowland Charity , Gibbons Chris
Published: April 2010

Augmentative and alternative communication (AAC) intervention offers people diagnosed with progressive nonfluent aphasia (PNFA) an opportunity to continue to communicate even as verbal expression declines. To date, there are no well-controlled studies reporting the effectiveness of AAC intervention with people who present with PNFA. Further, there is a pressing need for evidence about specific AAC intervention tools, techniques, and training protocols for persons with PNFA and their communication partners. We have engaged in research studies at the Oregon Health & Science University to quantify low-tech AAC supports for people with PNFA in highly controlled, as well as naturalistic, dyadic conversations. Preliminary results suggest that AAC provides strong lexical support for people with PNFA during conversation. We predict that training participants and their partners how to use personalized, low-tech communication boards will lead to reduced conversational scaffolding by partners and prolonged effective communication as the disease course progresses. Clinical implications and future directions of our research are discussed.
Primary Progressive Aphasia and Its Three Variants
Authors: Ogar Jennifer M.
Published: April 2010

Speech-language pathologists are increasingly treating patients with progressive disorders, including primary progressive aphasia (PPA). For many years, two variants of PPA were recognized: a nonfluent type—progressive nonfluent aphasia (PNFA)—and a fluent form—semantic dementia (SD). In 2004, a third variant—logopenic progressive aphasia (LPA)—was described. This article will review clinical symptoms, neuroimaging correlates, and the neuropathologies that are typically associated with PNFA, SD, and LPA. Case studies are included to further illustrate the characteristics of each of these three PPA variants.
Selected Values of Heats of Combustion and Heats of Formation of Organic Compounds Containing the Elements C, H, N, O, P, and S.
Authors: Domalski Eugene S.
Published: April 2010

Selected values of the heats of combustion and heats of formation of 719 organic compounds are reported here. The data tabulated pertain to compounds containing the elements carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur (CHNOPS). The information is arranged according to classes of compounds and within each class, compounds are arranged by empirical formula. The general classes covered are: hydrocarbons, alcohols, phenols, polyols, ethers, aldehydes, ketones, acids, acid anhydrides, esters, steroids, lactones, carbohydrates, heterocyclic oxygen compounds, amines, amides, urea derivatives, guanidine derivatives, amino acids, peptides, alkaloids, heterocyclic nitrogen compounds, porphyrins, organic sulfur compounds, and organic phosphorus compounds. When a selection was made from among several investigators, commentary is provided to indicate the choice, and usually some relevant data. The number of references cited is 596. An alphabetical compound index is provided which gives the name, page number, empirical formula, and the Wiswesser Line Notation (WLN), for each compound.
Thermal Conductivity of the Elements
Authors: Ho C. Y. , Powell R. W. , Liley P. E.
Published: April 2010

This is the abridged version of a comprehensive volume on the thermal conductivity of the elements. It contains recommended reference values resulting from critical evaluation, analysis, and synthesis of all the available data. It also gives estimated values for those elements for which no thermal conductivity data are available. Thus, the work provides recommended or estimated thermal conductivity values for all the elements over the full temperature ranges where experimental data are available or reliable extrapolations or estimations can be made. The results on each element are presented in both graphical and tabular forms. Summary graphs arranged by group in the periodic table are also given.
The Spectrum of Molecular Oxygen
Authors: Krupenie Paul H.
Published: April 2010

This is a critical review and compilation of the observed and predicted spectroscopic data on O2 and its ions O2−, O2+ and O22+ The ultraviolet, visible, infrared, Raman, microwave, and electron paramagnetic resonance spectra are included. Each electronic band system is discussed in detail, and tables of band origins and heads are given. The microwave and EPR data are also tabulated. Special subjects such as the dissociation energy of O2, perturbations, and predissociations are discussed. Potential energy curves are given, as well as f-values, Franck-Condon integrals, and other intensity factors. A summary table lists the molecular constants for all known electronic states of O2 and O2+ Electronic structure and theoretical calculations are also discussed.
A Critical Review of the Gas-Phase Reaction Kinetics of the Hydroxyl Radical
Authors: Wilson Wm. E.
Published: April 2010

The literature pertinent to reactions of the hydroxyl radical has been reviewed. An extensive discussion is given for reactions of the hydroxyl radical with itself and with CO, H2, and CH4. These four reactions are: (1) OH+OH→H2O+O; (2) CO+OH→CO2+H; (3) H2+OH→H2O+H; (4) CH4+OH→CH3+H2O.

Values are recommended for k1 and k2 and for the ratio k3/k2 and k4/k2. These rate ratios are used with the previously established value of k2 to obtain recommended values for k3 and k4.

The recommended values in cm3 mol-1·s-1, the temperature range, and the uncertainty are: k1=1.55×1012, 300 K, log k±0.1, 05k2=3.1×1011 exp(−300/T), 300−2000 K, log k±.3k3/k2=73 exp(2300/T), 300−2000 K, log k3/k2±.3k3=3.8×1013 exp(−2600/T), 300−2000 K, log k±.3k4/k2=92 exp(2200/T), 300−2000 K, log k3/k2±.3k4=2.85×1013 exp(−2500/T), 300−2000 K, log k±.7. Rate expressions are also recommended for a number of other hydroxyl reactions whose rates are less well established.
Rapid characterization of biomass using fluorescence spectroscopy coupled with multivariate data analysis. I. Yellow poplar (Liriodendron tulipifera L.)
Authors: Nkansah K. , Dawson-Andoh B.
Published: April 2010

This is the first of a two-paper series that reports on the use of fluorescence spectroscopy coupled with multivariate data analysis as a potential process analytical tool to develop calibration and prediction models for some physical and chemical properties of yellow poplar (Liriodendron tulipifera L.). Waste streams emanating from the processing of this wood species may potentially serve as feedstock for biofuels and biochemicals With the exception of holocellulose content, all the properties considered in the study were predicted with moderate to strong coefficient of determination (R2). Fluorescence spectra-based prediction model for each property considered in this study was compared with near infrared (NIR) spectra-based prediction models of similar properties from a previous study using the same population. The NIR-based prediction models exhibited slightly superior model strength over the fluorescence spectra-based prediction models of similar properties.
Quantum key distribution system in standard telecommunications fiber using a short wavelength single photon source
Authors: Collins R. J. , Clarke P. J. , Fernández V. , Gordon K. J. , Makhonin M. N. , Timpson J. A. , Tahraoui A. , Hopkinson M. , Fox A. M. , Skolnick M. S. , Buller G. S.
Published: April 2010

A demonstration of the principles of quantum key distribution (QKD) is performed using a single-photon source in a proof of concept test-bed over a distance of 2 km in standard telecommunications optical fiber. The single-photon source was an optically-pumped quantum dot in a microcavity emitting at a wavelength of 895 nm. Characterization of the QKD parameters was performed at a range of different optical excitation powers. An investigation of the effect of varying the optical excitation power of the quantum dot microcavity on the quantum bit error rate and cryptographic key exchange rate of the system are presented.
Probing single nanometer-scale pores with polymeric molecular rulers
Authors: Henrickson Sarah E. , DiMarzio Edmund A. , Wang Qian , Stanford Vincent M. , Kasianowicz John J.
Published: April 2010

We previously demonstrated that individual molecules of single-stranded DNA can be driven electrophoretically through a single Staphylococcus aureus α-hemolysin ion channel. Polynucleotides thread through the channel as extended chains and the polymer-induced ionic current blockades exhibit stable modes during the interactions. We show here that polynucleotides can be used to probe structural features of the α-hemolysin channel itself. Specifically, both the pore length and channel aperture profile can be estimated. The results are consistent with the channel crystal structure and suggest that polymer-based “molecular rulers” may prove useful in deducing the structures of nanometer-scale pores in general.
A multiscale description of charge transport in conjugated oligomers
Authors: Rühle Victor , Kirkpatrick James , Andrienko Denis
Published: April 2010

By relating inter- and intrachain ordering to charge dynamics a correlation between the morphology and charge mobility of neutral and doped states of a conjugated polymer, in this case polypyrrole, is established. Morphologies are generated using an all-atom force field, while charge dynamics is simulated within the framework of high temperature nonadiabatic Marcus theory. For short oligomers, charge carrier mobility is insensitive to the orientational molecular ordering and is determined by the threshold transfer integral which connects percolating clusters of molecules, forming interconnected networks. The value of this transfer integral can be estimated from the radial distribution function. We therefore find that charge mobility is mainly determined by the local molecular packing and is independent of global morphology, at least in such a noncrystalline state of a polymer.
Catalan solids derived from three-dimensional-root systems and quaternions
Authors: Koca Mehmet , Ozdes Koca Nazife , Koç Ramazan
Published: April 2010

Catalan solids are the duals of the Archimedean solids, the vertices of which can be obtained from the Coxeter–Dynkin diagrams A3, B3, and H3 whose simple roots can be represented by quaternions. The respective Weyl groups W(A3), W(B3), and W(H3) acting on the highest weights generate the orbits corresponding to the solids possessing these symmetries. Vertices of the Platonic and Archimedean solids result from the orbits derived from fundamental weights. The Platonic solids are dual to each other; however, the duals of the Archimedean solids are the Catalan solids whose vertices can be written as the union of the orbits, up to some scale factors, obtained by applying the above Weyl groups on the fundamental highest weights (100), (010), and (011) for each diagram. The faces are represented by the orbits derived from the weights (010), (110), (101), (011), and (111), which correspond to the vertices of the Archimedean solids. Representations of the Weyl groups W(A3), W(B3), and W(H3) by the quaternions simplify the calculations with no reference to the computer calculations.
Plasma channel diagnostic based on laser centroid oscillations
Authors: Gonsalves A. J. , Nakamura K. , Lin C. , Osterhoff J. , Shiraishi S. , Schroeder C. B. , Geddes C. G. R. , Tóth Cs. , Esarey E. , Leemans W. P.
Published: April 2010

A technique has been developed for measuring the properties of discharge-based plasma channels by monitoring the centroid location of a laser beam exiting the channel as a function of input alignment offset between the laser and the channel. Experiments were performed using low-intensity (<1014 W cm−2) laser pulses focused onto the entrance of a hydrogen-filled capillary discharge waveguide. Scanning the laser centroid position at the input of the channel and recording the exit position allow determination of the channel depth with an accuracy of a few percent, measurement of the transverse channel shape, and inference of the matched spot size. In addition, accurate alignment of the laser beam through the plasma channel is provided by minimizing laser centroid motion at the channel exit as the channel depth is scanned either by scanning the plasma density or the discharge timing. The improvement in alignment accuracy provided by this technique will be crucial for minimizing electron beam pointing errors in laser plasma accelerators.
Grain size dependence of coercivity in magnetic metal-insulator nanogranular films with uniaxial magnetic anisotropy
Authors: Yao Dongsheng , Ge Shihui , Zhou Xueyun , Zuo Huaping
Published: April 2010

Excellent soft magnetic properties and appropriate uniaxial magnetic anisotropy field have been achieved in a wide metal volume fraction (x) range for as-deposited (Fe65Co35)x(SiO2)1−x granular films fabricated by magnetron sputtering. With decreasing x from 0.86 to 0.53, the coercive force of easy axis Hce decreases clearly and shows the minimum value (Hce=0.85 Oe) at x=0.53. More importantly, not only nanoscale grain-size D contributing to small coercivity is proved, but also a D3 dependence of Hce is observed in the range of 0.53<x<0.86, which is similar to the results of Suzuki et al. reported for nanocrystalline alloys. Based on the random anisotropy model of Suzuki and Herzer, the grain-size D dependence of coercivity Hce in our metal-insulator granular film system was analyzed. Analyze results indicate that strong coherent uniaxial anisotropy which dominates over the random anisotropy ⟨K1⟩ of magnetic grains obtained by the random anisotropy model can be responsible for the D3 dependence of the coercivity Hce. In addition, in the range of 0.42<x<0.53, Hce (as well as Heh) increases with increasing x and then the D dependence of Hce deviates greatly from the D3 law, which is ascribed to the decrease in intergranular exchange coupling due to the increase in SiO2 insulator layer.
Complex-extended Bohmian mechanics
Authors: Chou Chia-Chun , Wyatt Robert E.
Published: April 2010

Complex-extended Bohmian mechanics is investigated by analytically continuing the wave function in polar form into the complex plane. We derive the complex-extended version of the quantum Hamilton–Jacobi equation and the continuity equation in Bohmian mechanics. Complex-extended Bohmian mechanics recovers the standard real-valued Bohmian mechanics on the real axis. The trajectories on the real axis are in accord with the standard real-valued Bohmian trajectories. The trajectories launched away from the real axis never intersect the real axis, and they display symmetry with respect to the real axis. Trajectories display hyperbolic deflection around nodes of the wave function in the complex plane.
An energy basin finding algorithm for kinetic Monte Carlo acceleration
Authors: Puchala Brian , Falk Michael L. , Garikipati Krishna
Published: April 2010

We present an energy basin finding algorithm for identifying the states in absorbing Markov chains used for accelerating kinetic Monte Carlo (KMC) simulations out of trapping energy basins. The algorithm saves groups of states corresponding to basic energy basins in which there is (i) a minimum energy saddle point and (ii) in moving away from the minimum the saddle point energies do not decrease between successive moves. When necessary, these groups are merged to help the system escape basins of basins. Energy basins are identified either as the system visits states, or by exploring surrounding states before the system visits them. We review exact and approximate methods for accelerating KMC simulations out of trapping energy basins and implement them within our algorithm. Its flexibility to store varying numbers of states, and ability to merge sets of saved states as the program runs, allows it to efficiently escape complicated trapping energy basins. Through simulations of vacancy-As cluster dissolution in Si, we demonstrate our algorithm can be several orders of magnitude faster than standard KMC simulations.
Onsager–Machlup action-based path sampling and its combination with replica exchange for diffusive and multiple pathways
Authors: Fujisaki Hiroshi , Shiga Motoyuki , Kidera Akinori
Published: April 2010

For sampling multiple pathways in a rugged energy landscape, we propose a novel action-based path sampling method using the Onsager–Machlup action functional. Inspired by the Fourier-path integral simulation of a quantum mechanical system, a path in Cartesian space is transformed into that in Fourier space, and an overdamped Langevin equation is derived for the Fourier components to achieve a canonical ensemble of the path at a finite temperature. To avoid “path trapping” around an initially guessed path, the path sampling method is further combined with a powerful sampling technique, the replica exchange method. The principle and algorithm of our method is numerically demonstrated for a model two-dimensional system with a bifurcated potential landscape. The results are compared with those of conventional transition path sampling and the equilibrium theory, and the error due to path discretization is also discussed.