bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of fire on the germination of spores ofPteridium caudatum, an invasive fern
Authors: Ramírez Trejo María del Rosario , Pérez-García Blanca , Pérez-Salicrup Diego R. , Orozco-Segovia Alma
Published: May 2010

Pteridium caudatumis a fern that frequently invades burnt areas in the Yucatán Peninsula and other neotropical sites. While post-fire regeneration of this fern apparently occurs mainly by vegetative means, little is known about the role of its spores in post-fire regeneration and in colonization of newly invaded fields. Central to these questions is whether bracken fern spores maintain their viability after fires. Here we experimentally evaluate the effect of fire-induced temperatures onPteridium caudatumspore germination. We used 1200-cm3blocks containing a constant fuel load of 47.4 g of litter, in which we placed spores at three different depths. The blocks were then ignited, and temperatures at each depth were monitored at 1-min intervals for 2 h. One day after the experimental fires, spores were dug out and cultured at 25 °C and 12-h light/dark cycles. Soil temperatures decreased significantly in relation to depth during fires. Spores on the surface were severely affected by fire, while those buried at 1 and 3 cm showed 77% germination. Germination in unburned controls was 86%. Our results suggest that during fires,Pteridium caudatumspores buried a few centimetres below the surface have a high percentage of viability, which could explain the rapid establishment of this species in burnt fields.
Climatic variables and altitude as predictors of anuran species richness and number of reproductive modes in Brazil
Authors: Vasconcelos Tiago da Silveira , Santos Tiago Gomes dos , Haddad Célio Fernando Baptista , Rossa-Feres Denise de Cerqueira
Published: May 2010

Because anuran species are highly dependent on environmental variables, we hypothesized that anuran species richness and the number of reproductive modes from different Brazilian localities vary according to climatic and altitudinal variables. Published data were compiled from 36 Brazilian localities and climatic and altitudinal data were extracted from an available database. A partial redundancy analysis (pRDA) showed that 23.5% of the data set's variation was explained by climatic and altitudinal data, while the remaining 76.5% remained unexplained. This analysis suggests that other factors not analysed herein may also be important for predicting anuran species richness and the number of reproductive modes in Brazil. Altitude and total annual rainfall were positively correlated with anuran species richness and the number of reproductive modes, and total annual rainfall was strongly associated with these two biotic variables in the triplot of pRDA. The positive association of total annual rainfall and the negative association of the concentration of annual rainfall were already expected based on physiological and reproductive requirements of anurans. On the other hand, temperature was not associated with richness or the number of reproductive modes.
Secondary seed dispersal by dung beetles in a Colombian rain forest: effects of dung type and defecation pattern on seed fate
Authors: Santos-Heredia Carolina , Andresen Ellen , Zárate Diego A.
Published: May 2010

In rain forests the fate of seeds defecated by mammals is often affected by dung beetles, but these effects can vary with mammal species. In a Colombian forest, differences in Scarabaeinae assemblages attracted to spider monkey (Ateles hybridus) and howler monkey (Alouatta seniculus) defecations were assessed. In total, 791 beetles of 35 species were captured. Mean number of individuals was similar for both dung types; mean number of species was higher forAlouattatraps. The effects of dung type (Alouattavs.Ateles) and defecation pattern (clumped vs. scattered) on the fate of 220Rollinia edulis(Annonaceae) seeds were determined. Burial by beetles occurred for 61% of the seeds (mean depth 2.6 cm). Seeds inAlouattadung and in clumped defecations had higher burial rates. Horizontal movement (mean 11 cm) occurred for 80% of the seeds; no significant effects of experimental factors were detected. Survival was higher for buried vs. surface seeds. In a separate experiment, no differences were detected between dung types in the proportion of seeds buried by beetles. Changes in dung texture might have been responsible for the contrasting results. When assessing the effectiveness of an endozoochorous plant–mammal interaction, secondary dispersal by dung beetles should be addressed too.
Is nest temperature an important factor for niche partitioning by leaf-litter ants (Hymenoptera: Formicidae) in Bornean rain forests?
Authors: Mezger Dirk , Pfeiffer Martin
Published: May 2010

We tested the hypothesis that species of a diverse leaf-litter ant community are separated by the temperature preferences of their broods along a thermal gradient. Therefore, temperature preferences of brood-tending workers from 41 ant species co-occurring in four types (alluvial, limestone, kerangas and dipterocarp forest) of primary rain forest in Sarawak, Malaysia were measured in an experimental set-up. Preferred temperatures of species ranged from 16.0 °C to 31.7 °C, with the median at 25.8 °C. The ten commonest species (n ≥ 4) showed significantly different temperature preferences. In particular, species of the genusPheidolediffered clearly in their preferences over a broad range of temperatures. Temperature preferences varied significantly among ant assemblages from different forest types and nest sites. Experimentally obtained temperature preferences of species correlated significantly with vegetation density in the plots inhabited by the respective species, but not with plot canopy cover. When we tested the temperature preferences of all ant species with null models for niche overlap, we found a significant niche separation only among the tested species from the kerangas. Our results suggest that nest temperature is an important ecological factor for leaf-litter ants in rain forests on Borneo, but other factors may override its influence during community assembly.
Receiver Interface Requirements for Deep INS/GNSS Integration and Vector Tracking
Authors: Groves Paul D , Mather Christopher J
Published: May 2010

Vector tracking of global navigation satellite systems (GNSS) signals and deeply integrating GNSS with an inertial navigation system (INS) improve robustness and accuracy in poor GNSS signal-to-noise environments. Both require a dedicated interface between the GNSS receiver and the navigation processor to enable the GNSS receiver to output the correlator measurements and input numerically-controlled oscillator (NCO) commands. This paper investigates the requirements for such an interface. Data latency is analysed for a range of different stand-alone GNSS vector tracking and deep INS/GNSS integration architectures. Suitable latency compensation techniques are identified. It is shown that, for the majority of applications, an NCO command update rate of 50 Hz with latency compensation and 100 Hz without is sufficient. An approach to interface standardisation which can handle a wide range of different GNSS signals and receiver designs is proposed.
Assessment of Radio Frequency Compatibility Relevant to the Galileo E1/E6 and Compass B1/B3 Bands
Authors: Liu Wei , Du Gang , Zhan Xingqun , Zhai Chuanrun
Published: May 2010

The intersystem interference between Galileo and Compass, known as a radio frequency compatibility problem, has become a matter of great concern for the system providers and user communities. This paper firstly describes two fundamentally different methods to assess the Global Navigation Satellite System (GNSS) intersystem interference, by using different interference coefficients that are calculated for each combination of signals: the spectral separation coefficient (SSC) and code tracking spectral sensitivity coefficient (CT_SSC). And then a complete methodology combining the SSC and CT_SSC is presented. Real simulations are carried out to assess the interference effects where Galileo and Compass signals are sharing the same band (E1/B1 and E6/B3 bands) at every time and place on the Earth. Simulation results show that the effects of intersystem interference are significantly different by using these two methodologies. It is also shown that the Compass system leads to intersystem interference on Galileo but that the maximal values are lower than Galileo interference to Compass. The design and implementation of any new signal has to be conducted carefully in order for there to be radio frequency compatibility.
THREE NEW SPECIES OF CHASSALIA AND PSYCHOTRIA (RUBIACEAE) FROM CENTRAL AFRICA
Authors: Lachenaud O. , Harris D. J.
Published: May 2010

Three new species of Rubiaceae from Central Africa are described and illustrated. Chassalia lutescens O.Lachenaud & D.J.Harris (widespread from Cameroon to Democratic Republic of Congo) is recognised inter alia by the T-shaped ventral furrow of the seeds and the orange-yellow discoloration of inflorescences in herbarium specimens. Psychotria nodiflora O.Lachenaud & D.J.Harris (Central African Republic, Congo-Brazzaville and Democratic Republic of Congo), belonging to Psychotria subgen. Psychotria sect. Involucratae, is unique among African species of the genus in having paired axillary inflorescences. Psychotria pteropus O.Lachenaud & D.J.Harris (Central African Republic and Democratic Republic of Congo) belongs to Psychotria subgen. Tetramerae; it is closely related to P. leptophylla Hiern but differs in its narrow corolla tube and globose to ellipsoid fruits.
TWO NEW SPECIES OF PARABOEA (GESNERIACEAE) FROM PENINSULAR MALAYSIA AND THAILAND
Authors: Kiew R.
Published: May 2010

Paraboea gracillima Kiew (Gesneriaceae) is described from Perlis, Malaysia, and from Ban Khamphaengphen in Peninsular Thailand. Paraboea lambokensis Kiew is described from two hills in Kelantan, Malaysia. Both are restricted to limestone. Paraboea lambokensis is endemic in Peninsular Malaysia and is Critically Endangered, while P. gracillima, which is protected in the Perlis State Park, is categorised as Least Concern.
Japanese Childhood Vaccination Policy
Authors: DOSHI PETER , AKABAYASHI AKIRA
Published: May 2010

The ethical tension in childhood vaccination policies is often framed as one of balancing the value of choice with the duty to protect. Because infectious diseases spread from person to person, unvaccinated children are usually described as putting others around them at risk, violating a perceived right to be protected from harm. Editors of Lancet Infectious Diseases recently argued against mandatory vaccination, reminding us that the resort to mandatory vaccination as a means of achieving high vaccination rates is still very much a topic of Western vaccine debates. The nation of Japan offers an interesting case study in childhood vaccination policy, as it has an entirely voluntary (opt-in) system that achieves high vaccination rates. In this paper, we offer an overview of Japanese childhood vaccine policy, suggest some ways to contextualize and understand how a voluntary system achieves high vaccination rates, and speculate on what the future of Japanese vaccination policymaking and government–public relations may hold.
Mental Health Acts in Canada
Authors: BROWNE ALISTER
Published: May 2010

There are 12 different Mental Health Acts (MHAs) in Canada, all of which provide for the involuntary confinement of the mentally disordered to protect both them from themselves and others from them. The Acts differ in many ways, but three issues stand out above all: (1) involuntary admission criteria, (2) the right to refuse treatment, and (3) who has the authority to authorize treatment. I first describe how the MHAs differ on these issues. I then take up the methodological question of how to select or construct a MHA from the many, all of which have something to be said for them. Finally, I apply this test to the three main issues in dispute and identify which solutions would be in an ideal MHA. My aim in this last is not to settle the issues but to engage with them and so deepen our understanding of what is at stake.
Bioethics in Iceland
Authors: ÁRNASON VILHJÁLMUR
Published: May 2010

Recent bioethics discussion and research in Iceland has been greatly affected by the fact that one of the world’s largest genetics research companies is based there and has been in the forefront of creating a population database resource for its research projects. Consequently, a large part of this article is centered around the bioethical discussion engendered by these projects, but other recent bioethical developments related to issues at the beginning and the end of life will also be discussed.
“Liberty, Solidarity, Fairness”: A Personal View of the French Healthcare System
Authors: ROTH MICHEL
Published: May 2010

Charles de Gaulle once famously complained about the difficulty of governing a nation with 250 different kinds of cheese (now estimates range from 400 to 1,000). His comment is a true description of France’s diversity and its population. We are like a loud, unruly family always arguing among ourselves. However, as much as we disagree, there is one thing on which we French stand united—we love our healthcare system and do not want it changed, even as economic realities make it increasingly difficult to maintain.
The Case: The “Ashley Treatment” Revisited
Authors: MISHRA RUCHIKA
Published: May 2010

To submit a case that has been reviewed by an ethics committee or to submit papers on related topics in clinical ethics, readers are invited to contact Ruchika Mishra, editor of “Ethics Committees at Work,” at: ruchika.mishra@gmail.com.
Commentary: What Kind of Fire or Whose Feet?
Authors: Paris John J. , Moore M. Patrick
Published: May 2010

Thirty years later we seem no closer to a consensus on the ethics of sterilizing profoundly mentally compromised young girls than was Judge Blumenfeld.
Commentary: Calibrating the Moral Compass
Authors: Holzman Ian R.
Published: May 2010

There is nothing more humbling to one’s inner moral compass than to realize that you do not initially know what is right or wrong! I found myself in just such a situation after reading the above case. Much has been written, both in the professional literature and the popular media, about the “Ashley Treatment” since Gunther and Diekema published their article in 2006. It is unclear if others in the United States or around the world have, to any significant degree, adopted growth attenuation therapy and/or surgical intervention for children with severe neurological compromise, but the case quoted above suggests that hospital ethics committees may also be struggling with these decisions. An informal survey of pediatric endocrinologists, mentioned in a recent article on the topic, claims that many physicians are facing this dilemma as well.
Anämien – die ersten Schritte in der Differentialdiagnose
Authors: Gähler Anita , Korte Wolfgang
Published: May 2010

Die Anämie ist ein häufiges Symptom, seltener allerdings eine Erkrankung für sich selbst. Meistens ist sie Symptom einer erworbenen oder hereditären Krankheit respektive Abnormalität. Die verschiedenen Situationen, welche zur Anämie führen können, umfassen beinahe das ganze Spektrum der Medizin. Oft stellt sich die Frage, ob die Anämie auf eine bereits bekannte Grunderkrankung zurückgeführt werden kann, oder ob nach einer anderen Ursache geforscht werden muss. Wir möchten in diesem Artikel auf generelle Konzepte der Anämieabklärung eingehen, Differentialdiagnosen vorstellen und einen möglichen Weg einer Ursachenabklärung der Anämie vorstellen.
Klinische Probleme erwachsener Sichelzellpatienten
Authors: Dickerhoff Roswitha , Heimpel Herrmann
Published: May 2010

Mit den Migranten der letzten Jahrzehnte sind die Sichelzellkrankheiten und die Thalassämien nach Mittel- und Nordeuropa gekommen. In den deutschsprachigen Ländern gibt es im Vergleich zu europäischen Nachbarn, die Kolonien in Afrika hatten, relativ wenige Sichelzellpatienten. Die meisten Ärzte betreuen höchstens 1 – 2 Patienten. Durch Fortschritte bei Prophylaxe und Therapie erreichen heute in USA und Europa 85 – 90 % der betroffenen Kinder das Erwachsenenalter. Da mit zunehmendem Alter zusätzlich zu akuten Krankheitsmanifestationen chronische Schäden aller Organe auftreten können, sind die klinischen Probleme der Sichelzellkrankheit sehr komplex; die Betreuung erfordert ein umfangreiches Wissen. Für die optimale Betreuung unserer Patienten sind wir angewiesen auf die Studienergebnisse amerikanischer und europäischer Zentren und die Hilfe erfahrener Kollegen. In dieser Arbeit wird auf die wichtigsten Krankheitsmanifestationen eingegangen und auf die zu Verfügung stehenden Informationsquellen hingewiesen.
Non Adherence – Non Response in der Transplantationsmedizin
Authors: Spengler Ulrich
Published: May 2010

Obwohl man es eigentlich anders erwarten würde, weisen über 50 % der Empfänger eines Organtransplantats unzureichende Adhärenz bei der Nachbetreuung auf. Akute Abstoßungen spät nach der Transplantation, vermehrter Transplantatverlust und erhöhte Mortalität sind die Folge. Diese Übersicht beschreibt Formen, typische Risikofaktoren der Nichtadhärenz bei transplantierten Patienten und skizziert mögliche Strategien zur Verbesserung adhärenten Verhaltens.
Trotz Blasenexstrophie ein gutes Leben haben: Untersuchung zum Leben und Umgang mit Blasenexstrophie
Authors: Seliner Brigitte , Gobet Rita , Metzenthin Petra , Spirig Rebecca
Published: May 2010

Die Blasenexstrophie (BE) stellt eine seltene, aber die schwerste urogenitale Fehlbildung dar und benötigt ein komplexes klinisches Management. Sie kann zu körperlichen, psychosozialen und psychosexuellen Beeinträchtigungen führen. Mit dieser qualitativen Studie wurde erstmals das Leben und der Umgang mit BE von der Kindheit bis zum frühen Alter (60 bis 80 Jahre) beschrieben. Das primäre Ziel war, Information zu gewinnen, um das Behandlungs- und Beratungsangebot für Betroffene am Kinderspital Zürich zu optimieren. Mit 16 Männern und 4 Frauen wurden halbstrukturierte Interviews geführt. Die Analyse anhand der qualitativen Inhaltsanalyse brachte drei Hauptkategorien zutage, mit zwei respektive fünf Subkategorien. In der ersten Hauptkategorie «Trotz BE ein gutes Leben haben» wird beschrieben, wie die Betroffenen trotz BE ihr Leben als etwas Gutes wahrnehmen. Diese Hauptkategorie beinhaltet krankheitsbezogene Episoden und Erfahrungen wie «Im Spital sein», «Mit Symptomen leben», «Anderssein» «Sich offenbaren» und «Informationen suchen». In der zweiten Hauptkategorie werden «die Mitbetroffenen» wie «die Partner/-in» und «die Eltern» beschrieben, welche von der BE beeinflusst werden und eine große Unterstützung leisten. Die Wahrnehmung und Erfahrungen der Betroffenen werden durch vier individuelle und kontextuelle Faktoren beeinflusst, die in der dritten Hauptkategorie beschrieben werden.
Das Ehrenamt bei der Unterstützung von Pflegebedürftigen und ihren Familien: Profil und Motive
Authors: Fringer André , Mayer Herbert , Schnepp Wilfried
Published: May 2010

Pflegende Angehörige werden zunehmend durch bürgerschaftlich Engagierte im häuslichen Bereich mit sogenannten «niedrigschwelligen» Entlastungsangeboten unterstützt, da sie oft mit der Pflege überfordert sind. Über die Notwendigkeit von bürgerschaftlichem Engagement in diesem Bereich können in der Literatur zudem unterschiedliche Aspekte, die das Profil der Ehrenamtlichen beschreiben, identifiziert werden. Die Leitidee einer «neuen Kultur des Helfens» findet in unterschiedlichen Modellprogrammen ihren Ausdruck. Im Zeitraum von 2005 bis 2008 wurde ein solches Modellprojekt in NRW, das niedrigschwellige Entlastung für pflegende Angehörige anbietet, mithilfe eines Fallstudiendesigns wissenschaftlich begleitet. Ziel der vorliegenden Untersuchung war es, das Profil der Ehrenamtlichen darzustellen, deren Motive zu erfassen und Gründe für den Ausstieg aus dem Modellvorhaben zu identifizieren. Insgesamt wurden N = 52 Ehrenamtliche mit einem standardisierten Fragebogen vor ihrem ersten Einsatz in der Häuslichkeit und nach sechs Monaten im Einsatz befragt. Die Motivationen für das Engagement unterscheiden sich zwischen der Erst- und der Zweitbefragung insbesondere bei der «Aufwandsentschädigung» und dem «Bedürfnis nach Stärkung des Selbstwertgefühls» signifikant. Die Aufwandsentschädigung an sich stellt primär keinen Anreiz dar, um sich als Ehrenamtlicher motivieren zu lasen; sie ist jedoch ein nicht zu unterschätzender Aspekt der Anerkennung für geleistete Hilfen.
Wie erleben Erfasserinnen den Umgang mit der Observed Emotional Rating Scale?
Authors: Händler-Schuster Daniela , Geschwindner Heike , Oppikofer Sandra , Them Christa
Published: May 2010

Da im deutschsprachigen Raum bisher kaum empirische Daten zur Anwendung der Observed Emotion Rating Scale (OERS) bei demenzerkrankten Personen vorliegen, sollte im Rahmen des Pilotprojekts «Agitation» untersucht werden, wie Erfasserinnen den Einsatz des Instruments OERS erleben. Zu diesem Zweck konnten 12 Probandinnen gewonnen werden, die in drei Pflegezentren im Kanton Zürich Beobachtungen mit dem Instrument OERS durchführten. Der überwiegende Teil der Probandinnen verfügte über pflegerische Qualifikationen bzw. Erfahrung im Umgang mit demenzerkrankten Personen. Die Datensammlung erfolgte anhand von drei Fokusgruppeninterviews, die mittels einer qualitativen Inhaltsanalyse ausgewertet worden waren. Die vorläufigen Ergebnisse aus den Fokusgruppeninterviews wurden von denselben Probandinnen anhand eines Fragebogens validiert. Die Kategorien «fehlende Eindeutigkeit», «fehlende Kodiermöglichkeit», «Demenzschwere», «Einschätzen von Emotionen», «Einflussfaktoren» und «Anwenderschulung» zeigten, dass das Wissen um die Demenzerkrankung genauso bedeutsam ist wie eine geübte Handhabung der OERS.
Evaluation der Pflege- und Führungskompetenz – eine Ausgangslage für die weitere Praxisentwicklung
Authors: Martin Jacqueline S. , Frei Irena Anna , Suter-Hofmann Franziska , Fierz Katharina , Schubert Maria , Spirig Rebecca
Published: May 2010

Kompetente Pflege und effektives Leadership sind wichtige Voraussetzungen für die Bereitstellung einer qualitativ hochwertigen, evidenzbasierten, patienten- und ergebnisorientierten Patientenversorgung. Die Abteilung Klinische Pflegewissenschaft (KPW) am Universitätsspital Basel (USB) entwickelte und implementierte Programme zur gezielten Praxisentwicklung, welche die pflegerische Kompetenz sowie die des Leadership fördern. Zur Erfassung von Pflege- und Leadership-Kompetenz sowie der Arbeitsumgebungs- und Pflegequalität führte die KPW 2007 eine Evaluationsstudie mit einem Mixed-Method-Design durch. Am quantitativen Anteil der Studie nahmen 679 Pflegefachpersonen und 27 Stationsleitungen teil. Die deskriptiven Resultate zeigen, dass Pflegefachpersonen ihre durchschnittliche pflegerische Kompetenz über alle sieben Subkategorien der Nurse Competence Scale mit einem Mittelwert von 75,1 (VAS 0 – 100) beurteilten. Die Leadership-Kompetenz von Stationsleitungen wurde im oberen Drittel der Skala des Leadership Practice Inventory mit mittleren Werten zwischen 40 bis 50 (Meanscore: 6 – 60) eingeschätzt. Als Qualitätssicherungsmaßnahme sind regelmäßige Nachfolgeerhebungen im Sinne eines Monitoring geplant. Solche Erhebungen werden in Zukunft von zentraler Bedeutung sein, da zu erwarten ist, dass sich mit der Einführung des DRG-Finanzierungsmodells im schweizerischen Gesundheitswesen der Kontext der pflegerischen Leistungen verändern wird.
Ocean‐atmosphere partitioning of anthropogenic carbon dioxide on multimillennial timescales
Authors: Goodwin Philip , Ridgwell Andy
Published: May 2010

Ocean‐sediment and weathering interactions exert the primary control on how much anthropogenic‐emitted CO2 remains in the atmosphere on timescales longer than about 1 kyr. Analytical theory is presented which predicts, from initial conditions, the remaining atmospheric fraction of emitted CO2 after equilibrium with CaCO3 burial in deep‐sea sediments but before silicate weathering removes all excess CO2 on a >100 kyr timescale. The theoretical predictions of final atmospheric CO2 partial pressure are tested against independent integrations of the GENIE‐1 Earth system model and are found to agree to within 10% for total emissions up to about 4000 PgC. The predicted theoretical relationship is linear and is based on the assumptions that ocean carbonate ion concentration is restored when CaCO3 burial reaches a new steady state, and that the steady state change in global ocean CO2* is proportional to the change in atmospheric CO2; where CO2* is the combined concentration of aqueous CO2 and carbonic acid. We find that the residual fraction of anthropogenic CO2 in the atmosphere can be determined without explicit use of ocean [CO32−], even though this concentration is known to be important in controlling the depth interval over which CaCO3‐rich sediments accumulate. The simple theory developed here is particularly suited for efficient assessment of events recorded in the geological record as well as anthropogenic CO2 influences on the long‐term stability of ice sheets.
Substorm convection and current system deduced from the global simulation
Authors: Tanaka T. , Nakamizo A. , Yoshikawa A. , Fujita S. , Shinagawa H. , Shimazu H. , Kikuchi T. , Hashimoto K. K.
Published: May 2010

The substorm mechanism is investigated by analyzing the numerical results obtained through the use of the recently refined magnetohydrodynamic model. After showing the growth phase features, the numerical solution reproduces the observed signatures of a substorm onset, including the formation of a near‐Earth neutral line (NENL), earthward directed flow in the plasma sheet, a dipolarization, a geosynchronous D deflection, the development of the nightside field aligned currents (FACs), and electrojets in the ionosphere. The onset is triggered by a sudden collapse of the plasma sheet and a successive formation of a high‐pressure region in the inner magnetosphere. The energy source of this high‐pressure region is the magnetic tension released from the NENL. The tail disturbance is primary transmitted to the ionosphere by the region 2 FAC accompanying the high‐pressure region formed in the inner magnetosphere. The associated nightside region 1 FAC is not connected to the traditional current wedge but to the cusp region. The region 1 FAC path to the ionosphere develops from dayside to nightside, so as to construct a grand loop with the region 2 FAC from the partial ring current. In the grand loop, the region 1 FAC provides a short circuit in the ionosphere for the region 2 FAC. In the expansion phase, convection enhances to relax the distorted pressure distribution formed at the onset, accompanied by a further development of dipolarization and a thickening of the plasma sheet in the magnetosphere and increases in the westward and eastward electrojets in the ionosphere. The present model can explain the explosive growth phase and the thinning of the midtail plasma sheet just after the onset.
Structure and dynamics of the Columbia River tidal plume front
Authors: Kilcher Levi F. , Nash Jonathan D.
Published: May 2010

Time‐dependent buoyant plumes form at the outflow of tidally dominated estuaries. When estuary discharge velocity exceeds plume internal wave speed c, a sharp front forms at the plume's leading edge that expands from the time‐dependent source. Using observations of the Columbia River tidal plume from multiple tidal cycles we characterize time‐evolving plume structure and quantify front speed Uf, plume internal wave speed c, front curvature, and ultimate extent. We identify three distinct stages of propagation: (1) Initially, the plume is strongly influenced by shallow bathymetry near the river mouth. (2) As the front advances offshore the plume detaches from the bottom and expands as a freely propagating gravity current with relatively constant Uf, c and frontal Froude number F = Uf/c. Ambient currents explain intracycle variability in Uf and winds alter front shape. Variability in ambient stratification associated with previous cycles' plume remnants leads to complex fronts and internal waves. (3) Finally, the plume decelerates, adjusts toward geostrophy, and may radiate additional internal waves. Using a simple kinematic model, we suggest that constant frontal propagation speed, Uf = 0.9 ± 0.1 m/s, during stage 2 is primarily controlled by linearly increasing volume flux from the Columbia River mouth. As this discharge rate subsides, the plume expands as a fixed volume with decreasing front speed (stage 3). The plume's final extent is controlled by the Rossby radius, which scales with a length based on the total volume discharged. This provides an integral description of plume front evolution based on the time‐dependent estuary discharge.
Broken and inhomogeneous cloud impact on satellite cloud particle effective radius and cloud‐phase retrievals
Authors: Wolters Erwin L. A. , Deneke Hartwig M. , van den Hurk Bart J. J. M. , Meirink Jan Fokke , Roebeling Robert A.
Published: May 2010

The impact of sensor resolution on satellite‐derived cloud particle effective radius (re) and cloud phase (CPH) for broken and overcast inhomogeneous clouds is investigated for the Cloud Physical Properties (CPP) retrieval algorithm used by the Climate Monitoring Satellite Application Facility. First, synthetic data sets of high‐resolution (1 × 1 km2) and low‐resolution (3 × 3 km2) radiances are used to illustrate the effect on the re and cloud top temperature (CTT) retrieval, the cloud properties that are used for the CPH retrieval. It is shown that low‐resolution re can be overestimated by up to 12 μm and CTT by up to 20 K for thick broken and inhomogeneous overcast water clouds over ocean and land surfaces. The overestimation of re may cause erroneous assignments of “ice” to water clouds. Second, 2 months of CPP retrievals on Moderate Resolution Imaging Spectroradiometer (MODIS) radiances are used to quantify the effect on re and CPH over the Atlantic Ocean and central Europe. Over both areas, the low‐resolution re is overestimated by up to +5 μm for broken and up to 2 μm for inhomogeneous overcast clouds. At low resolution, the fraction of water clouds is underestimated by 2.3% over the Atlantic Ocean and 0.6% over central Europe. The increase of CTT partly compensates for the increase in re in the CPH retrievals at low resolution. If no CTT information were used, the underestimation of the water cloud fraction would be 3.5% and 2.2% for the Atlantic Ocean and central Europe, respectively. For inhomogeneous overcast clouds integrated over all inhomogeneity classes, the difference is −1.3% and −2.3% for central Europe and the Atlantic Ocean, respectively. Our results indicate that (1) the retrieval of re in the CPP algorithm is sensitive to satellite sensor resolution in case of broken clouds and inhomogeneous overcast clouds and (2) despite this large re sensitivity the CPH retrieval is much less sensitive to sensor resolution.
A priori covariance estimation for CO2 and CH4 retrievals
Authors: Eguchi N. , Saito R. , Saeki T. , Nakatsuka Y. , Belikov D. , Maksyutov S.
Published: May 2010

We derive the a priori covariance matrices of CO2 and CH4 for the retrieval of their profiles and columns from satellite spectral data. The monthly a priori covariance matrices of CO2 and CH4 at each grid cell (0.5° × 0.5°) on the globe are calculated using simulated data from the atmospheric tracer transport model. The a priori covariance matrix is defined as the sum of the bias and noise components, where the bias is obtained from the difference in seasonal cycle between simulated data and observation‐based reference data, and the noise is defined as synoptic and interannual variations. The use of simulated data as well as observation‐based reference data enables realistic variance and covariance values to be obtained for each temporal component. The seasonal bias is approximately 2 ppm for CO2 and 20 ppb for CH4. A large difference in synoptic variations is obtained between simulated and reference data over the source region, especially over land. The interannual variances derived from the reference data show maximum values (4 ppm2 for CO2 and 220 ppb2 for CH4) in northern midlatitudes. Global data sets of a priori covariance matrices for CO2 and CH4 are now available for the retrieval of concentrations using satellite spectral data. Furthermore, the data set has the potential to be applied in studies in other fields, including estimates of CO2 flux error using inverse modeling and planning for ground‐based observation networks.
A long‐term stratospheric ozone data set from assimilation of satellite observations: High‐latitude ozone anomalies
Authors: Kiesewetter G. , Sinnhuber B.‐M. , Vountas M. , Weber M. , Burrows J. P.
Published: May 2010

A 29 year data set of stratospheric ozone from sequential assimilation of solar backscatter UV (SBUV) satellite ozone profile observations into a chemical transport model is introduced and validated against independent observations (satellite instruments and sondes). Our assimilated data set shows excellent agreement with ozone profile data from sonde measurements from high‐latitude observation sites on both hemispheres and Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) satellite observations, including during polar night when no SBUV observations are available. Although we only assimilate ozone profiles, total column ozone in the assimilated data set is in good agreement with independent satellite observations from the Global Ozone Monitoring Experiment (GOME), the Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY), and the Total Ozone Mapping Spectrometer (TOMS). The data set can thus be viewed as a consistent long‐term data set closing the gaps in satellite observations in order to investigate high‐latitude ozone variability. We then use the assimilated data set to analyze the development and persistence of both high and low ozone anomalies in the Arctic stratosphere. Ozone anomalies typically develop in the 1000 K potential temperature (∼35 km) region and slowly descend from there, remaining visible for around 7 months. Anomalies in the stratospheric circulation, expressed by the Northern Hemisphere annular mode (NAM) index, show a large influence on ozone anomalies. Extreme phases of the NAM index (strong and weak vortex events) lead to the creation of distinctively shaped ozone anomalies, which first appear in the uppermost stratosphere and then rapidly cover the upper and middle stratosphere, from where they then slowly descend into the lowermost stratosphere within 5 months.
Architecture and Neogene to Recent evolution of the western Calabrian continental margin: An upper plate perspective to the Ionian subduction system, central Mediterranean
Authors: Pepe Fabrizio , Sulli Attilio , Bertotti Giovanni , Cella Federico
Published: May 2010

The western Calabria continental margin forms the transition between the Pliocene to Recent Marsili spreading center and continental Calabria, all parts of the upper plate of the Ionian subduction zone. Integrating high‐resolution and crustal seismic images constrained by gravity modeling, we provide a detailed reconstruction of the architecture of the margin and develop a new scheme for its Miocene to present evolution. This time span encompasses the continent‐continent collision between Africa and Eurasia, subsequent orogenic collapse and rifting apart between the two continental masses, and the Pliocene to Recent emplacement of oceanic crust in the Vavilov and Marsili basins. The crust of the margin thins from the Calabria coast (∼25 km) to the Marsili continent‐ocean transition (∼12 km). On the whole, upper and lower crusts thin proportionally with pure shear geometry. The continental margin is covered by an Oligocene(?) to present sedimentary succession reaching a maximum thickness of ∼6.0 km in the Paola Basin. During the Miocene the continental margin experienced regional shortening accommodated by a large number of mainly west vergent thrusts possibly associated with the late stages of the Kabilo‐Calabrian chain. Shortening continued through Pliocene to Recent but was accommodated by a limited number of west vergent thrust faults located in the western part of the margin and by a few tens of kilometers wide syncline located in the eastern part of the profile. The accommodation space created in the syncline core hosted a ∼4.5 km thick, Plio‐Quaternary sedimentary succession, the Paola Basin. No significant extensional fault is observed along the profile. Miocene to Recent subsidence was controlled by (1) a short‐wavelength component related to shortening and responsible for the formation of the Paola Basin syncline and, possibly, contributing to the uplift of onshore Calabria and (2) a long‐wavelength component responsible for the regional subsidence and oceanward tilting of the Calabria margin. Short‐wavelength subsidence ended in the late Pliocene, but long‐wavelength downward movements persisted and even accelerated during late Pliocene(?) to Quaternary times when the present‐day bathymetry was achieved. Both horizontal deformations and vertical movements are difficult to explain in the context of a normal back‐arc basin without taking into consideration patterns of secondary mantle flow generated by the retreat of the subducting slab.
Combining geologic‐process models and geostatistics for conditional simulation of 3‐D subsurface heterogeneity
Authors: Michael H. A. , Li H. , Boucher A. , Sun T. , Caers J. , Gorelick S. M.
Published: May 2010

The goal of simulation of aquifer heterogeneity is to produce a spatial model of the subsurface that represents a system such that it can be used to understand or predict flow and transport processes. Spatial simulation requires incorporation of data and geologic knowledge, as well as representation of uncertainty. Classical geostatistical techniques allow for the conditioning of data and uncertainty assessment, but models often lack geologic realism. Simulation of physical geologic processes of sedimentary deposition and erosion (process‐based modeling) produces detailed, geologically realistic models, but conditioning to local data is limited at best. We present an aquifer modeling methodology that combines geologic‐process models with object‐based, multiple‐point, and variogram‐based geostatistics to produce geologically realistic realizations that incorporate geostatistical uncertainty and can be conditioned to data. First, the geologic features of grain size, or facies, distributions simulated by a process‐based model are analyzed, and the statistics of feature geometry are extracted. Second, the statistics are used to generate multiple realizations of reduced‐dimensional features using an object‐based technique. Third, these realizations are used as multiple alternative training images in multiple‐point geostatistical simulation, a step that can incorporate local data. Last, a variogram‐based geostatistical technique is used to produce conditioned maps of depositional thickness and erosion. Successive realizations of individual strata are generated in depositional order, each dependent on previously simulated geometry, and stacked to produce a fully conditioned three‐dimensional facies model that mimics the architecture of the process‐based model. We demonstrate the approach for a typical subsea depositional complex.
Present‐day motion and deformation of the Colorado Plateau
Authors: Kreemer Corné , Blewitt Geoffrey , Bennett Richard A.
Published: May 2010

We analyze data from continuous GPS stations in the southwestern United States and present the first observations of a systematic motion of the Colorado Plateau region. Relative to a North America‐fixed reference frame, westward velocities increase rapidly across the Wasatch fault system, which comprises the plateau's northwestern margin, but increase more gradually between the Great Plains and the Mojave Desert province. We detect no significant extension across most of the Rio Grande Rift, but extension could be as high as ∼0.5 mm yr−1 along its southernmost portion. We suggest that the motion between the plateau and stable continent may partly be accommodated instead across the Jemez Lineament. Only when we consider GPS velocities within the plateau's center, do the data support a rigid body rotation of 0.103° Ma−1 around a pole in the northern Rocky Mountains. We conclude that active extension has encroached into the plateau from both the east and west.
Cdc48 and Ufd3, new partners of the ubiquitin protease Ubp3, are required for ribophagy
Authors: Ossareh‐Nazari Batool , Bonizec Mélanie , Cohen Mickael , Dokudovskaya Svetlana , Delalande François , Schaeffer Christine , Van Dorsselaer Alain , Dargemont Catherine
Published: May 2010

Ubiquitin‐dependent processes can be antagonized by substrate‐specific deubiquitination enzymes involved in many cellular functions. In this study, we show that the yeast Ubp3–Bre5 deubiquitination complex interacts with both the chaperone‐like Cdc48, a major actor of the ubiquitin and proteasome system, and Ufd3, a ubiquitin‐binding cofactor of Cdc48. We observed that these partners are required for the Ubp3–Bre5‐dependent and starvation‐induced selective degradation of yeast mature ribosomes, also called ribophagy. By contrast, proteasome‐dependent degradation does not participate in this process. Our data favour the idea that these factors cooperate to recognize and deubiquitinate specific substrates of ribophagy before their vacuolar degradation.
ATAC and Mediator coactivators form a stable complex and regulate a set of non‐coding RNA genes
Authors: Krebs Arnaud R , Demmers Jeroen , Karmodiya Krishanpal , Chang Nan‐Chi , Chang Alice Chien , Tora László
Published: May 2010

The Ada‐Two‐A‐containing (ATAC) histone acetyltransferase and Mediator coactivator complexes regulate independent and distinct steps during transcription initiation and elongation. Here, we report the identification of a new stable molecular assembly formed between the ATAC and Mediator complexes in mouse embryonic stem cells. Moreover, we identify leucine zipper motif‐containing protein 1 as a subunit of this meta‐coactivator complex (MECO). Finally, we demonstrate that the MECO regulates a subset of RNA polymerase II‐transcribed non‐coding RNA genes. Our findings establish that transcription coactivator complexes can form stable subcomplexes to facilitate their combined actions on specific target genes.
The stabilisation of organometallic complexes usingm-terphenyl ligands
Authors: Kays Deborah L.
Published: May 2010

The use of bulky monodentate m-terphenyl ligands in the stabilisation of d-block organometallic compounds is surveyed. Importantly, these ligands have facilitated the isolation of hitherto unknown species containing low-coordinate centres and metal-metal multiple bonds. This review reports on these advances with emphasis on the synthesis, structural characterisation and, where possible, reactivity studies of complexes featuring metal-carbon bonds between m-terphenyl ligands and the transition metals.
Recent developments in the chemistry of metal-metal multiply bonded paddlewheel compounds
Authors: Patmore Nathan J.
Published: May 2010

This review summarises the main developments in the chemistry of metal-metal multiply bonded paddlewheel compounds reported in the literature between 2007 and 2008.
The Future of Glycerol
Authors: Pagliaro Mario , Rossi Michele
Published: May 2010

By-products of global biodiesel manufacturing are a modern day global fact responsible for igniting a number of year’s worldwide intense research activity into human chemical ingenuity. This fully updated and revised 2nd edition depicts how practical limitations posed by glycerol chemistry are solved based on the understanding of the fundamental chemistry of glycerol and by application of catalysis science and technology. The authors report and comment on employable, practical avenues applicable to convert glycerol into value added products of mass consumption. This book is the best-selling reference book in the field. The highly anticipated 2nd Edition is essential reading for anyone interested in understanding whether biodiesel and glycerol refineries are convenient and economically sound.
Floating harmonics method for measuring electron temperature in non-Maxwellian plasmas
Authors: Bang Jin Young , Kim ARam , Chung Chin Wook
Published: May 2010

Electron temperatures obtained from the slope of the electron energy probability function (EEPF) at the floating potential were compared with those measured by the floating harmonics method in various electron distributions. Basically, these two types of the electron temperatures should be same in a Maxwellian electron distribution. As expected, discrepancies were observed between them in cases of non-Maxwellian distribution. In this study, the second and third harmonics of probe current were used to obtain the electron temperature in non-Maxwellian distribution. The experimental results were shown that the electron temperature obtained using this method was in good agreement with the electron temperature from the slope of the EEPF at floating potential, regardless of the electron distribution.
Two-by-two random matrix theory with matrix representations of octonions
Authors: Nieminen John M.
Published: May 2010

The recently established pseudo real matrix representations of octonions [Y. Tian, Adv. Appl. Clifford Algebras 10, 61 (2000)] are discussed in connection with 2×2 random matrix theory. A random matrix model that can be tuned to produce level repulsion from linear to octic is developed and nearest-neighbor spacing distributions for this model are presented.
Picosecond ultrasonic experiments with water and its application to the measurement of nanostructures
Authors: Yang F. , Grimsley T. J. , Che S. , Antonelli G. A. , Maris H. J. , Nurmikko A. V.
Published: May 2010

The propagation of ultrashort sound pulses in water has been studied by using the picosecond ultrasonic technique and a pulse time-of-flight technique for measuring the depths of deep channels in Si-based nanostructure was demonstrated. The sound pulses were generated when light was absorbed in a metal transducer film and detected by a time-delayed probe light pulse. First, the attenuation and velocity of sound of frequency 4.8 GHz in water were measured through an analysis of the Brillouin frequency oscillations in the reflectivity of the probe light. Measurements at frequencies up to about 11 GHz were made by sending a sound pulse across a thin layer of water and measuring the change in shape of the returning echo due to the attenuation of the different Fourier components. Second, we also report on proof-of-concept ultrasonic experiments to acquire spatial profile information from nanostructures, where sound pulses propagate down narrow channels in patterned nanostructures. We have been able to detect acoustic echoes for sound propagating along a channel as narrow as 35 nm.
Calculation of the magnetic surface function gradient in stellarators with broken stellarator symmetry
Authors: Nemov V. V. , Kasilov S. V. , Kernbichler W. , Seiwald B.
Published: May 2010

The computation of the gradient of the magnetic surface function, ∇ψ, plays an essential role in plasma physics, e.g., for investigations of plasma equilibrium currents or transport fluxes in stellarators. The evaluation of ∇ψ becomes more complicated if the magnetic field B does not exhibit stellarator symmetry. Here, a scheme for computation of ∇ψ for magnetic configurations which do not show stellarator symmetry is presented. The proposed method is based on computations of gradients of integrals of magnetic field line equations. This new technique for ∇ψ calculations is applied to Uragan-2M [O. S. Pavlichenko for the U-2M group, Plasma Phys. Controlled Fusion 35, B223 (1993)]. Taking into account the influence of current feeds and detachable joints of the helical winding the magnetic configuration does not exhibit stellarator symmetry. Computations of ∇ψ, the effective ripple ϵeff, and the geometrical factor λb for the bootstrap current in the 1/ν transport regime are performed.