bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ice regime of the lower Peace River and ice‐jam flooding of the Peace‐Athabasca Delta
Authors: Beltaos Spyros , Prowse Terry D. , Carter Tom 
Published: November 2006

AbstractThe Peace‐Athabasca Delta (PAD) in northern Alberta is one of the world's largest inland freshwater deltas, home to large populations of waterfowl, muskrat, beaver, and free‐ranging wood bison. Beginning in the mid‐1970s, a paucity of ice‐jam flooding in the lower Peace River has resulted in prolonged dry periods and considerable reduction in the area covered by lakes and ponds that provide a habitat for aquatic life in the PAD region. Using archived hydrometric data and in situ observations, the ice regime of the lower Peace is described and quantified, setting the stage for identification of the conditions that lead to ice‐jam flooding and replenishment of Delta habitat. The first such condition is the occurrence of a mechanical, as opposed to a thermal, breakup event; second, the river flow should be at least 4000 m3/s; and third, an ice jam should form within the last 50 km of the Peace River. The type of breakup event depends on the freeze‐up stage and spring flow. The former has increased as a result of flow regulation, and the latter has decreased owing to changing climatic patterns. Both trends tend to inhibit the occurrence of mechanical breakups and contribute to less frequent ice‐jam flooding. Potential mitigation strategies are discussed. Copyright © 2006 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.
Climatic effects on ice‐jam flooding of the Peace‐Athabasca Delta
Authors: Beltaos S. , Prowse T. , Bonsal B. , MacKay R. , Romolo L. , Pietroniro A. , Toth B. 
Published: November 2006

AbstractThe Peace‐Athabasca Delta (PAD) in northern Alberta is one of the world's largest inland freshwater deltas, home to large populations of waterfowl, muskrat, beaver, and free‐ranging wood bison. In recent decades, a paucity of ice‐jam flooding in the lower Peace River has resulted in prolonged dry periods and considerable reduction in the area covered by lakes and ponds that provide habitat for aquatic life in the PAD region. Building on previous work that has identified the salient hydro‐climatic factors, the frequency of ice‐jam floods is considered under ‘present’ (1961–1990) and ‘future’ (2070–2099) climatic conditions. The latter are determined using temperature and precipitation output from the Canadian Climate Centre's second‐generation Global Climate Model (CGCM2) for two different greenhouse‐gas/sulphate emission scenarios. The analysis indicates that the ice season is likely to be reduced by 2–4 weeks, while future ice covers would be slightly thinner than they are at present. More importantly, a large part of the Peace River basin is expected to experience frequent and sustained mid‐winter thaws, leading to significant melt and depleted snowpacks in the spring. Using an empirical relationship between ice‐jam flood occurrence and size of the spring snowpack, a severe reduction in the frequency of ice‐jam flooding is predicted under both future‐climate scenarios that were considered. In turn, this trend is likely to accelerate the loss of aquatic habitat in the PAD region. Implications for potential mitigation and adaptation strategies are discussed. Copyright © 2006 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.
Reconstruction of multi‐century flood histories from oxbow lake sediments, Peace‐Athabasca Delta, Canada
Authors: Wolfe Brent B. , Hall Roland I. , Last William M. , Edwards Thomas W. D. , English Michael C. , Karst‐Riddoch Tammy L. , Paterson Andrew , Palmini Roger 
Published: November 2006

AbstractFloods caused by ice‐jams on the Peace River are considered to be important for maintaining hydro‐ecological conditions of perched basins in the Peace‐Athabasca Delta (PAD), Canada, a highly productive and internationally recognized northern boreal ecosystem. Concerns over the potential linkages between regulation of the Peace River in 1968 for hydroelectric production and low Peace River discharge between 1968 and 1971 during the filling of the hydroelectric reservoir, absence of a major ice‐jam flood event between 1975 and 1995, and low water levels in perched basins during the 1980s and early 1990s have sparked numerous environmental studies largely aimed at restoring water levels in the PAD. Lack of sufficient long‐term hydrological records, however, has limited the ability to objectively assess the importance of anthropogenic factors versus natural climatic forcing in regulating hydro‐ecological conditions of the PAD. Here, we report results of a paleolimnological study on laminated sediments from two oxbow lakes in the PAD, which are located adjacent to major flood distributaries of the Peace River. Sediment core magnetic susceptibility measurements, supported by results from several other physical and geochemical analyses as well as stratigraphic correspondence with recorded high‐water events on the Peace River, provide proxy records of flood history spanning the past ∼180 and ∼300 years in these two basins. Results indicate that inferred flood frequency has been highly variable over the past 300 years but in decline for many decades beginning as early as the late nineteenth century, well before Peace River regulation. Additionally, several multi‐decadal intervals without a major flood have occurred during the past 300 years. While climate‐related mechanisms responsible for this variability in flood frequency remain to be determined, as does quantifying the relative roles of river regulation and climate variability on hydro‐ecological conditions in the PAD since 1968, these results suggest that ecosystem management strategies for the PAD need to explicitly account for natural variations in flood recurrence intervals. Copyright © 2006 John Wiley & Sons, Ltd.
IR, Raman and SERS spectra of 3,5‐dinitrosalicylic acid
Authors: Varghese Hema Tresa , Panicker C. Yohannan , Philip Daizy , Chowdhury Joydeep , Ghosh Manash 
Published: November 2006

AbstractIR, Raman and surface enhanced Raman scattering (SERS) spectra of 3,5‐dinitrosalicylic acid (DNSA) were recorded and analysed. The vibrational wavenumbers were computed by the ab initio method using RHF/6–21G* basis and they were found to be in good agreement with the experimental values. The effect of the concentration dependence on the SERS intensity of the molecule was studied. The molecular plane assumes a tilted orientation with respect to the silver surface. Copyright © 2006 John Wiley & Sons, Ltd.
Smooth muscle caveolae differentially regulate specific agonist induced bladder contractions
Authors: Cristofaro V. , Peters C.A. , Yalla S.V. , Sullivan M.P. 
Published: November 2006

AbstractAimsCaveolae are cholesterol‐rich plasmalemmal microdomains that serve as sites for sequestration of signaling proteins and thus may facilitate, organize, and integrate responses to extracellular stimuli. While previous studies in the bladder have demonstrated alterations in caveolae with particular physiologic or pathologic conditions, little attention has been focused on the functional significance of these organelles. Therefore, the purpose of this study was to investigate the role of caveolae in the modulation of receptor‐mediated signal transduction and determine the presence and localization of caveolin proteins in bladder tissue.MethodsContractile responses to physiologic agonists were measured in rat bladder tissue before and after disruption of caveolae achieved by depleting membrane cholesterol with methyl‐β‐cyclodextrin. Stimulation with agonists was repeated after caveolae were restored as a result of cholesterol replenishment. RT‐PCR, immmunohistochemistry, and Western blotting were used to determine the expression and localization of caveolin mRNA and proteins.ResultsFollowing caveolae disruption, contractile responses to angiotensin II and serotonin were attenuated, whereas responses to bradykinin and phenylephrine were augmented. Cholesterol replenishment restored responses towards baseline. Carbachol and KCl induced contractions were not affected by caveolae disruption. Ultrastructure analysis confirmed loss of caveolae following cholesterol depletion with cyclodextrin and caveolae restoration following cholesterol replacement. Gene and protein expression of caveolin‐1, ‐2, and ‐3 was detected in bladder tissue. Immunoreactivity for all three caveolins was observed in smooth muscle cells throughout the bladder.ConclusionsThe functional effects of cholesterol depletion on specific agonist‐induced contractile events and the expression of all three caveolins in bladder smooth muscle support a central role for caveolae in regulation of selective G‐protein‐coupled receptor signaling pathways in bladder smooth muscle. Thus, caveolae serve to differentially regulate bladder smooth muscle by a stimulus‐dependent potentiation or inhibition of bladder contraction. Neurourol. Urodynam. © 2006 Wiley‐Liss, Inc.
Outcome of retinoblastoma in east Africa
Authors: Bowman R.J.C. , Mafwiri M. , Luthert P. , Luande J. , Wood M. 
Published: November 2006

AbstractWe estimated the proportion of patients reaching a pediatric ophthalmology unit (Comprehensive Community Based Rehabilitation for Tanzania Disability Hospital, CCBRT) or an oncology unit (ORCI) in east Africa and investigated presentation, histology, and treatment outcomes of patients with retinoblastoma. A 5‐year retrospective study identified 91 patients, representing approximately 18% of the nationwide total. Mean lag time was 10 months (standard deviation (SD) = 17) and mean follow‐up was 8 months (SD = 11, range 0–40, n = 91). Thirty months disease‐free survival probability was 0.23 (standard error = 0.07). Outcomes for retinoblastoma in Africa remain poor. The data presented here suggest strategies for improving the outcomes, including encouraging earlier presentation and establishment of multi‐disciplinary treatment centers. Pediatr Blood Cancer 2008;50:160–162. © 2006 Wiley‐Liss, Inc.
Degenerate thermal isomerizations of Z‐ethylidene‐2‐methylcyclobutane
Authors: Baldwin John E. 
Published: November 2006

AbstractThe stereochemical and mechanistic aspects of the degenerate thermal isomerizations available to deuterium‐labeled Z‐ethylidene‐2‐methylcyclobutanes remain incompletely defined. Relevant data and several conjectural readings of the data are reconsidered in light of current understandings of thermal stereomutations and [1,3] carbon sigmatropic shifts. Copyright © 2006 John Wiley & Sons, Ltd.
Mental health literacy in Japanese cancer patients: ability to recognize depression and preferences of treatments—comparison with Japanese lay public
Authors: Okuyama Toru , Nakane Yoshibumi , Endo Chiharu , Seto Takashi , Kato Masashi , Seki Nobuhiko , Akechi Tatsuo , Furukawa Toshiaki A. , Eguchi Kenji , Hosaka Takashi 
Published: November 2006

AbstractBackground: Insufficient knowledge about mental illness and its treatment has been shown to constitute a major barrier to its adequate care for mental illness in the lay public (LP). We therefore examined Japanese cancer patients' (CP) ability to recognize depression and their preferences of its treatments.Participants and Method: One hundred lung CP and 300 LP were selected at random to participate in the study. Structured interviews using a vignette of a person with both cancer and depression were conducted with CP, and those using a vignette of a person with depression were carried out with LP, respectively.Results: Only 11% of CP recognized the presence of depression in the vignette, while 25% of LP did (p<0.001). There were few significant differences in the preference for standard psychiatric treatments between CP and LP: standard treatments such as antidepressants (CP: 39%, LP: 36%) were less often rated as helpful, whereas non‐standard treatments such as physical activity (CP: 85%, LP: 66%) were most often rated as helpful.Conclusions: The results indicated that cancer patients' knowledge about mental illness and its treatment were insufficient. Psychological education may reduce patient‐related barriers to seek and to utilize optimal mental health care in cancer patients. Copyright © 2006 John Wiley & Sons, Ltd.
Design, synthesis and pharmacological evaluation of cyclic mimetics of the insulin‐like peptide 3 (INSL3) B‐chain
Authors: Shabanpoor Fazel , Bathgate Ross A. D. , Hossain Mohammed Akhter , Giannakis Eleni , Wade John D. , Hughes Richard A. 
Published: November 2006

AbstractInsulin‐like peptide 3 (INSL3) is a peptide hormone belonging to the relaxin‐insulin superfamily of peptides that plays important roles in testes descent, oocyte maturation and the control of male germ cell apoptosis. These actions are mediated via a specific G‐protein coupled receptor, LGR8. Previous structure–activity studies have shown that the key binding site of INSL3 is situated within its B‐chain. Recent studies in our laboratory have led to the identification of a cyclic peptide mimetic 2 of the INSL3 B‐chain, which we have shown to compete with the binding of [33P]‐relaxin to LGR8 expressed in HEK293T cells, and to inhibit cAMP‐mediated signaling in these cells, i.e. it is an antagonist of INSL3. In order to further define the structure–activity relationships of cyclic analogues of the INSL3 B‐chain, we used a structure‐based approach to design a series of cyclic, disulfide‐constrained INSL3 B‐chain mimetics. To do this, we first created a model of the 3D structure of INSL3 using the crystal structure of human relaxin as a template. This model of INSL3 was then used as a template to design a series of disulfide‐constrained mimetics of the INSL3 B‐chain. The peptides were synthesized by solid‐phase peptide synthesis using pseudoproline dipeptides to improve the synthesis outcome. Of the seven prepared INSL3 B‐chain mimetics, three compounds were found to have partial displacement activity, while four were able to completely displace [33P]‐relaxin from LGR8, including compounds that were markedly shorter than compound 2. The best of these, mimetic 6, showed significantly greater affinity for LGR8 than compound 2, but still displayed around 1000‐fold less affinity for LGR8 than native INSL3. Analysis of selected mimetics for their α‐helical content using circular dichroism (CD) spectroscopy revealed that, generally, the mimetics showed less than expected helicity. The inability of the compounds to display true native INSL3 structure is likely contributing to their reduced receptor binding affinity. We are currently examining alternative INSL3 B‐chain mimetics that might better present key receptor binding residues in the native INSL3‐like conformation. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd.
Mn‐doped II‐VI quantum dots: artificial molecular magnets
Authors: Fernández‐Rossier J. , Aguado R. 
Published: November 2006

AbstractThe notion of artificial atom relies on the capability to change the number of carriers one by one in semiconductor quantum dots, and the resulting changes in their electronic structure. Organic molecules with transition metal atoms that have a net magnetic moment and display hysteretic behaviour are known as single molecule magnets (SMM). The fabrication of CdTe quantum dots chemically doped with a controlled number of Mn atoms and with a number of carriers controlled either electrically or optically paves the way towards a new concept in nanomagnetism: the artificial single molecule magnet. Here we study the magnetic properties of a Mn‐doped CdTe quantum dot for different charge states and show to what extent they behave like a single molecule magnet. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron spin coherence in singly charged (In,Ga)As/GaAs quantum dots
Authors: Greilich A. , Oulton R. , Zhukov E. A. , Yugova I. A. , Yakovlev D. R. , Bayer M. , Shabaev A. , Efros Al. L. , Merkulov I. A. , Stavarache V. , Reuter D. , Wieck A. 
Published: November 2006

AbstractOptical generation of electron spin coherence has been studied in n ‐modulation doped (In,Ga)As/GaAs quantum dots which contain on average a single electron per dot. For studying the spin coherence, the magnetic field was applied in the Voigt‐geometry, and the precession of the electron spin about the field was monitored. The coherence is generated by resonant excitation of the quantum dots by circularly‐polarized laser pulses, creating a coherent superposition of an electron and a trion state. The efficiency of the generation can be controlled by the pulse intensity, showing the pronounced Rabi oscillations. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical spectroscopy of single, planar, self‐assembled InAs/InP quantum dots
Authors: Kim D. , Lefebvre J. , Lapointe J. , Reimer M. E. , Mckee J. , Poole P. J. , Williams R. L. 
Published: November 2006

AbstractWe present optical spectra from numerous, single, self‐assembled InAs/InP quantum dots. More than 50 individual dots are studied that emit in the 1.1‐1.6 mm wavelength range. The dots are of high optical quality as judged by the clean, single exciton emission line at low power, the resolution limited linewidth, and the brightness. Each dot exhibits similar trends in the power evolution spectra, despite large variations in height and diameter. The level splittings in the p ‐shell increase with decreasing height, which we interpret to be from dot elongation along the [01$ \bar 1 $] direction. The evolution of the spectra with increasing power agrees well with predictions from effective bond orbital calculations. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum information processing on spin degrees of freedom in QDs placed in diluted magnetic semiconductor
Authors: Jacak W. , Krasnyj J. , Jacak J. , Krzyżosiak M. , Jacak L. 
Published: November 2006

AbstractThe spin degrees of freedom in quantum dot (QD) embedded in a diluted magnetic semiconductor (DMS) medium are considered in a model of a qubit and a gate for quantum information processing (QIP). The qubit is defined as a singlet and triplet pair of states of two electrons in a He‐type QD in the DMS medium with strongly enhanced gyromagnetic factor. Methods of qubit rotation (Rabi oscillations) as well as two‐qubit operations are suggested and analyzed. Moreover, decoherence related to spin waves (magnon‐induced dephasing) in this new system (QD in DMS) is studied, and the relevant time‐scale is estimated in accordance with preliminary experimental results. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Carrier‐induced coherent acoustic phonon excitation in strain engineered InAs/GaAs quantum dot clusters
Authors: Bogaart E. W. , van Lippen T. , Nötzel R. , Haverkort J. E. M. , Wolter J. H. 
Published: November 2006

AbstractStrain engineered InAs/GaAs quantum dot (QD) clusters grown on (311)B GaAs are studied by means of time‐resolved differential reflection spectroscopy revealing coherent excitation of the quasilongitudinal and quasitransverse acoustic phonon modes. Photogenerated carriers which are captured within the ordered lateral QD clusters initiate coherent acoustic phonon excitation, which induces a transient modulation of the local strain‐induced piezoelectric field within the QD clusters. The excited acoustic phonons modulate the optical properties of the QDs through the quantum‐confined Stark effect, causing oscillations of the reflection signal. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical properties of single InGaN quantum dots up to 150 K
Authors: Sebald K. , Lohmeyer H. , Gutowski J. , Yamaguchi T. , Hommel D. 
Published: November 2006

AbstractWe present photoluminescence measurements on single InGaN quantum dots grown by metalorganic vapor phase epitaxy. The spatially and spectrally resolved luminescence properties of the single quantum dots were measured using low‐temperature micro‐photoluminescence spectroscopy. The observed sharp emission lines of the quantum dots were characterized by excitation density dependent measurements. The photoluminescence of individual quantum dots can easily be detected for temperatures up to 150 K. In addition, temporal fluctuations of the emission peak positions of single quantum dots are attributed to spectral diffusion processes. Indications for recombination processes from excited states are observed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum dot photonic crystal nanocavities at 1300 nm for telecom‐wavelength single‐photon sources
Authors: Francardi M. , Balet L. , Gerardino A. , Monat C. , Zinoni C. , Li L. H. , Alloing B. , Le Thomas N. , Houdré R. , Fiore A. 
Published: November 2006

AbstractPhotonic Crystal (PhC) nanocavities have shown to be good candidates to enhance the spontaneous emission (SE) rate of an emitter into a specific cavity mode (Purcell effect) and allow the implementation of single photon sources. We report our progress in the fabrication of PhC nanocavities with high quality factors in the 1300 nm region. PhC nanocavities with H1 and L3 geometries were characterised in a microphotoluminescence set‐up at room temperature. The quality factor was studied as a function of lattice constant a, filling factor, lateral displacement and radius of holes adjacent to the cavity in the L3 geometry. A Q = 3000 is measured in a L3 cavity with filling factor = 35%, a = 311 nm, displacement of 0.125 a and r = 0.53r0. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
InAs(Sb) quantum dots grown on GaAs by MBE
Authors: Sallet V. , Patriarche G. , Mauguin O. , Largeau L. , Travers L. 
Published: November 2006

AbstractThe MBE growth of InAs(Sb)/GaAs quantum dots is investigated. Photoluminescence shows a slight red‐shift of the emission wavelength from 1.15 to 1.24 µm (InAs0.95Sb0.05 dots). Attempts to incorporate higher concentrations of antimony lead to a poor optical quality and, occasionally, to a blue‐shift. Trans‐mission electron microscopy observations are discussed considering the surfactant effect of antimony. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
InAs(Sb)/InP(100) quantum dots for mid‐infrared emitters: observation of 2.35 µm photoluminescence
Authors: Doré F. , Cornet C. , Caroff P. , Ballestar A. , Even J. , Bertru N. , Dehaese O. , Alghoraibi I. , Folliot H. , Piron R. , Le Corre A. , Loualiche S. 
Published: November 2006

AbstractTheoretical and experimental studies of the electronic properties of InAs(Sb) quantum dots (QDs) grown on InP substrate are presented. Unstrained bulk InAsSb present direct gap between 0.1 eV to 0.35 eV suitable for mid infrared emitters (2‐5 µm). However, strain and quantum confinement effects may limit the extension of the emission spectrum of these nanostructures towards the longer wavelengths. Various combinations of barrier materials are considered in the simulations. Photoluminescence (PL) spectroscopy experiments on molecular beam epitaxy (MBE) grown samples show promising results. We obtained PL peak beyond 2 µm at room temperature (RT) with InAs/InGaAsP/InP(100) QDs High arsine flow rate during the growth of the QDs makes possible this long emission wavelength. Two ways are investigated to incorporate antimony in InAs/InGaAs/InP(100) nanostructures: growth interrupt of InAs QDs under Sb flux and direct growth of InAs(Sb). A red‐shift of the PL peak from 1.85 µm to 2 µm is observed in the first case whereas emission wavelengths as long as 2.35 µm are observed in second case. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Top‐down approach of completely sequencing a 4.9 kDa recombinant peptide using quadrupole time‐of‐flight mass spectrometry
Authors: Deepalakshmi Putchen Dakshinamoorthy 
Published: November 2006

AbstractA recombinant peptide (near the C‐terminal region of head involution defective protein) of 4.9 kDa has been completely sequenced and characterized using medium‐resolution mass spectrometry (QTOF). The observed difference in the experimental mass and the theoretical mass is due to β‐mercaptoethanol adduct formation on the cysteine residue. The fragmentation pattern is correlated with the primary structure of the protein. Top‐down sequencing of the peptide was extended to small proteins like barstar of mass 10.3 kDa. Copyright © 2006 John Wiley & Sons, Ltd.