bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wisconsinan Late‐glacial environmental change in Nova Scotia: A regional synthesis
Authors: Mott R. J. 
Published: February 2007

AbstractA synthesis of the interpreted vegetational and climatic history of Nova Scotia during the Wisconsinan Late‐glacial period (14‐9 ka BP) is presented and described in 500‐year intervals. The concomitant regional deglaciation history of the region is also described. A synthesis chart is provided which includes a qualitative curve of temperature reconstructions for the Lateglacial period.
Wisconsinan Late‐glacial environmental change in Newfoundland: A regional review
Authors: Anderson T. W. , Macpherson J. B. 
Published: February 2007

AbstractThe distribution of 75 lake and bog sites, from which pollen stratigraphical evidence relevant to the late Quaternary of Newfoundland has been obtained, is presented. The detailed records of lithology, pollen and diatoms, supplemented by geochemical data, are discussed for three of the sites — Southwest Brook Lake, Woody Hill Brook Pond and Leading Tickles — and interpretations made are based on vegetational history, relative climatic changes and extent of ice cover. Radiocarbon data from 14 sites are summarised. A summary chart of Late‐glacial environmental changes, including a qualitative palaeotemperature curve, is provided.
Hierarchical biostratigraphical classification of long pollen sequences
Authors: Tzedakis P. C. 
Published: February 2007

AbstractThe biostratigraphical classification of long pollen sequences in relation to the definition of pollen assemblage biozones according to the International Stratigraphic Guide is examined. To facilitate the description and organization of pollen stratigraphical data the concept of a ‘pollen assemblage superzone’ is introduced. A hierarchical approach relying on superzones, zones and subzones appears to be better suited to the different levels of variation encountered in long pollen sequences and is here applied to a recored from the loannina basin, northwest Greece.
Degree of rock surface weathering as an indicator of ice‐sheet thickness along an east—west transect across southern Norway
Authors: Nesje Atle , McCarroll Danny , Dahl Svein Olaf 
Published: February 2007

AbstractRock surface weathering, as reflected by rock surface hardness and roughness, was measured at six mountains along an east‐west transect across southern Norway. At most sites the results show significant differences in rock surface weathering across the autochthonous blockfield boundary, suggesting that the areas above the boundary have been exposed to subaerial weathering for a considerably longer time span that the areas below. The results are interpreted as reflecting the surface profile of an asymmetric, west‐centred, low‐gradient ice sheet.
Stratigraphy and sedimentology of Devensian (Dimlington Stadial) glacial deposits, east Yorkshire, England
Authors: Evans David J. A. , Owen Lewis A. , Roberts David 
Published: February 2007

AbstractThe stratigraphy and sedimentology of the glacial deposits exposed along the coast of east Yorkshire are reviewed. Critical sections at Filey Brigg, Barmston and Skipsea are examined to reassess the stratigraphy of Devensian Dimlington Stadial glacial deposits in the light of recent developments in glacial sedimentology. Sedimentary and glaciotectonic structures studied in the field and by using scanning electron microscopy are emphasised. Two hypotheses are considered for the genesis of the interbedded diamictons and stratified sediments. The first involves the deposition of lodgement till and/or deformation till followed by meltout till, which was overridden to produce more deformation till, reflecting periods of ice stagnation punctuated by glacier thickening. The second hypothesis, which is favoured on the basis of field evidence and micromorphology, involves the vertical accretion of a deforming till layer associated with cavity/channel or tunnel valley fills, beneath active ice. At Barmston the upper part of the diamicton contains elongate pendant structures containing gravels, indicating that the diamicton was saturated and able to flow. The diamictons, therefore, represent a complex sequence of tills deposited and deformed by active ice during the Dimlington Stadial. Previously published stratigraphical schemes involving classifications of multiple tills in east Yorkshire should be simplified and it is more appropriate to assign these to a single formation, the Skipsea Till Formation. Rhythmic glaciolacustrine and proglacial glaciofluvial sediments overlie the tills at Barmston and Skipsea. These were deposited in sag basins during deglaciation as the tills settled and deformed under thickening sediment and as buried ice melted out. Extensive sands and gravels cap the succession and were deposited on a sandur during the later stages of deglaciation.
Patterned fen development in northern Scotland: Hypothesis testing and comparison with ombrotrophic blanket peats
Authors: Charman Daniel J. 
Published: February 2007

AbstractPatterned fens are part of the diverse Holocene peatland landscape of the Flow Country, northern Scotland. Their present vegetation and morphology allies them with boreal systems in Scandinavia and North America. However, previous work has shown that their mode of formation is rather different and has suggested a developmental model in which the poor fens have formed only recently and have arisen as a result of local hydrological change. These ideas are tested here by morphological, stratigraphical and macrofossil studies on three additional patterned fens covering a wider geographical and ecological range. Two sites corroborate the hypotheses of the earlier study, and one site which refutes the earlier findings can be shown to be dependent on different topographic controls. A comparison of two patterned fens with an ombrotrophic mire site in the same area shows that hydroseral processes dominate the early development of individual components of the mire complex. The time of initiation of patterned fens coincides with increasing surface wetness on the ombrotrophic mire. This may be due to climatic change and/or the coalescence of the constituent parts of the present integrated blanket mire system. The hydrological changes arising from this led to the emergence of the springs that currently supply the patterned fens with their water and elevated nutrient levels. The study supports the idea that landscape‐scale research and conservation are essential for the understanding and hydrological integrity of blanket mire landscapes such as the Flow Country.
Last interglacial and Holocene climatic development in the Norwegian Sea region: Ocean front movements and ice‐core data
Authors: Sejrup Hans Petter , Haflidason Haflidi , Kristensen Dorthe Klitgaard , Johnsen Sigfus J. 
Published: February 2007

AbstractPlanktonic foraminiferal evidence suggests that the ocean front systems between Polar and Atlantic surface waters in the Norwegian Sea generally were located closer to Greenland during Oxygen Isotope Substage 5e than in the Holocene. During both these periods oscillations have occurred in the position of the fronts. In the western Norwegian Sea region, the substage 5e influence of warm Atlantic waters was interrupted by a return to polar conditions. These findings support both ice‐core data and evidence from Europe that the last interglacial was a period of rapid climatic shifts.
Composite Hydrogels: Robust Carriers for Catalytic Nanoparticles
Authors: Lu Yan , Spyra Paul , Mei Yu , Ballauff Matthias , Pich Andrij 
Published: February 2007

AbstractA new type of composite hydrogel have been synthesized in which “nano‐tree” type polymer brush particles have been chemically entrapped in a poly(vinyl alcohol) (PVA) matrix by means of the disulfone reaction. This reaction leads to a chemical crosslinking of the nano‐tree brush particles within the PVA hydrogel. Obtained composite hydrogels can be successfully used as template for the deposition of Ag nanoparticles. Field‐emission scanning electron microscopy (FESEM) images demonstrate that monodisperse Ag nanoparticles (ca. 35 nm) are embedded into the composite hydrogel: Most of the silver nanoparticles were generated on the surface of the brush particles while a small amount of Ag nanoparticles was found to be entrapped within the PVA polymer network. We demonstrate that the resulting composite hydrogels can be used as a robust carrier for generation and immobilization of catalytically active Ag nanoparticles. The catalytic activity is investigated by monitoring the reduction of 4‐nitrophenol by NaBH4 in the presence of such a kind of composite hydrogel. The hybrid hydrogels can be easily reused many times as a catalyst and the catalytic activity can be retained over several months.magnified image
Retirement and transition phenomena in the family purchase process
Authors: Stammerjohan Claire Allison , Capella Louis M. , Taylor Ronald D. 
Published: February 2007

AbstractResearch is needed on the family purchase process of retirement‐age couples, because 78 million baby boomers are rapidly approaching retirement age. Both boomers and the retirement‐age couples in this study present special opportunities to marketers through new roles adopted in retirement. This study reports on perceptions of family purchase process participation among retirement‐age couples. Results indicate that transition retirees' family purchase process participation differs from that of post‐transition retirees. This finding has managerial implications for marketers wishing to serve desirable segments of current and future retirement‐age consumers. © 2007 Wiley Periodicals, Inc.
Effect of caffiene on microsurgical technical performance
Authors: Urso‐Baiarda Fulvio , Shurey Sandra , Grobbelaar Adriaan O. 
Published: February 2007

AbstractMicrosurgeons may choose to avoid caffeine to prevent potentially deleterious caffeine tremor, although an adverse effect on surgical skill has never been shown. This double‐blind placebo‐controlled crossover study investigated the effect of moderate caffeine intake on microsurgical ability among microsurgical training course attendees. Subjects were randomized to receive either morning placebo and afternoon caffeine, or the reverse, thereby acting as their own controls. Performance in end‐to‐end vessel anastomosis was graded by a single observer during both sessions using a global rating scale. Subjects consuming caffeine in the morning demonstrated significantly improved scores from morning to afternoon, whereas subjects consuming caffeine in the afternoon showed no such improvement. These results are consistent with an adverse effect of caffeine on microsurgical skill combined with a learning curve among the study population of novice microsurgeons, and support the view that caffeine has a detrimental effect on microsurgical ability among this study group. © 2007 Wiley‐Liss, Inc. Microsurgery, 2007.
Selection of the sacral nerve posterior roots to establish skin–CNS–bladder reflex pathway: An experimental study in rats
Authors: Wang Jinwu , Hou Chunlin , Jiang Jia , Li Qi , Zhang Feng 
Published: February 2007

AbstractThe purpose of this study was to explore the innervations of different sacral nerve posterior roots to bladder, and to provide evidence for further study of skin–CNS–bladder reflex pathway in the spinal cord injury patient. Spinal cord injury was produced in 10 rats. The bilateral spinal posterior roots of S1–S4 were electrically stimulated, and the bladder plexus action, bladder smooth muscle complex action potential, and intravesical pressure were examined and measured. The results showed that all the sacral nerve posterior roots were involved in innervations of bladder in rats. Among them, the S2 sacral nerve is the dominant nerve in innervations of bladder, followed by S1, S3, and S4 sacral nerve posterior roots. This study has provided valuable information for selection of sacral nerve posterior root for further study of the artificial bladder reflex arc for improving the micturition function in spinal cord injury patients. © 2007 Wiley‐Liss, Inc. Microsurgery, 2007.
Responsiveness of rabbits to superovulation treatment by a single injection of follicle‐stimulating hormone with aluminum hydroxide gel
Authors: Hashimoto Shu , Kimura Koji , Kuramochi Takashi , Aoyagi Kazuki , Hirako Makoto , Kawaguchi Mamoru , Iwata Hisataka , Hirao Masao , Kitada Kensaku , Hirasawa Kazuo , Ueda Masatsugu 
Published: February 2007

AbstractAluminum hydroxide gel (Al‐gel), which is used as an adjuvant, can absorb macromolecules. We investigated the applicability of Al‐gel to the sustained release of follicle‐stimulating hormone (FSH) as a simplified method of superovulation (SOV) in rabbits. The responsiveness of rabbits to SOV by a single injection of FSH dissolved in Al‐gel suspension (3.2 mg Al/ml) and in 10% (w/v) polyvinylpyrrolidone (PVP), and by multiple injections of FSH in saline was examined. The numbers of total and fertilized eggs recovered from rabbits treated with FSH in Al‐gel (40.5 and 26.3, respectively) were similar to multiple injections (47.4 and 28.6, respectively) and were significantly greater (P < 0.05) than single injection of FSH with PVP (17.3 and 11.5, respectively). We also compared the plasma FSH levels of rabbits which were induced SOV by multiple or a single injection of Al‐gel. Al‐gel provided sustained release of FSH to the blood stream at a high enough dose for SOV. Moreover, the developmental competence of the pups of DNA‐injected embryos from rabbits treated with a single injection of FSH mixed with Al‐gel (18%) was similar to that of DNA‐injected embryos, recovered from rabbits treated with FSH dissolved in saline (21%). Two transgenic pups were obtained from embryos recovered from rabbits by a single injection of FSH with Al‐gel. These results indicate that a single injection of FSH with Al‐gel is an effective method for SOV of rabbit and that this technique is applicable to research requiring large numbers of rabbit embryos such as the production of transgenic rabbits. Mol. Reprod. Dev. 74: 1208–1212, 2007. © 2007 Wiley‐Liss, Inc.
High mobility group box 1 (HMGB1) is implicated in preimplantation embryo development in the mouse
Authors: Cui Xiang‐Shun , Shen Xing‐Hui , Kim Nam‐Hyung 
Published: February 2007

AbstractHigh mobility group box 1 (HMGB1) regulates multiple cell functions, including transcription, DNA repair, differentiation, and apoptosis. In order to obtain insight into the role of HMGB1 in embryo development, we first evaluated its gene expression levels in mouse preimplantation embryos. Quantitative real‐time reverse transcription‐polymerase chain reaction (RT‐PCR) revealed high expression levels in zygotes, and expression steadily increased after zygotic genome activation when normalized to the rabbit Globin mRNA. Indirect immunocytochemistry showed that the HMGB1 protein was also produced in mouse embryos. Injection of a small interfering RNA (siRNA) specific for HMGB1 into zygotes specifically reduced both mRNA expression (P < 0.001) and protein synthesis of HMGB1 in early embryos developed in vitro. Injection of siRNA into the zygote did not affect development to the blastocyst stage, but significantly decreased cell numbers (P < 0.01) in the blastocyst and increased caspase3 (Casp3, P < 0.05) gene expression and apoptosis (P < 0.005). Addition of recombinant HMGB1 (Sigma, H‐4652) into the culture medium enhanced the development of zygote stage mouse embryos to blastocysts, in the absence of BSA supplementation. These findings suggest that endogenous and exogenous HMGB1 are implicated in preimplantation embryo development in the mouse. Mol. Reprod. Dev. 75: 1290–1299, 2008. © 2007 Wiley‐Liss, Inc.
Distinct responses of human granulosa lutein cells after hCG or LH stimulation in a spheroidal cell culture system
Authors: Becker Julia , Walz Andrea , Daube Stefanie , Keck Christoph , Pietrowski Detlef 
Published: February 2007

AbstractThe growth and development of the corpus luteum (CL) is regulated by gonadotropic hormones. It is formed by granulosa cells (GCs), theca cells, and endothelial cells, and is the primary source of circulating progesterone. During early pregnancy only human chorionic gonadotropin (hCG) but not luteinizing hormone (LH) extends the life span of the CL, although hCG and LH interact with the same receptor and have similar actions on the CL. In this study a recently by our group established spheroidal GC culture assay served as a model of CL development on which we compared the actions of the gonadotropic hormones LH and hCG. To find out which signal pathways take part in the hormonal regulation of GC we stimulated GC‐spheroids with modulators of protein kinases A and C dependent signaling cascades and determined their impact on sprout forming activity in GC. Our results indicate that PKA‐dependent signaling pathways play a major role in mediating the hormonal‐induced signaling cascades leading to sprouting in GC. Furthermore, this study strongly indicates that the different effects of hCG and LH in the maintenance of the CL may be reasoned in different signal transduction pathways triggered by hCG or LH. Mol. Reprod. Dev. 74: 1312–1316, 2007. © 2007 Wiley‐Liss, Inc.
Polypeptide backbone derived from carboxyl terminal of mouse ZP3 inhibits sperm‐zona binding
Authors: Li Ding , Cao Shaofeng , Xu Chen 
Published: February 2007

AbstractFor mammalian organism, fertilization begins with species‐specific recognition between sperm and egg, a process depending upon egg zona pellucida glycoproteins and putative sperm interacting protein(s). In mouse, zona pellucida glycoprotein ZP3 is believed to be the primary receptor for sperm and inducer of sperm acrosomal reaction, and its function has been attributed to the specific O‐linked oligosaccharides attached to polypeptide backbone. While lots of reports have focused on the role of ZP3's oligosaccharides in fertilization, there are few concerning its polypeptide backbone. To investigate whether mZP3 polypeptide backbone is involved in sperm‐egg recognition, three partially overlapping cDNA fragments, together covering entire mouse ZP3, were cloned, expressed and purified under denaturing condition. Although all three refolded proteins possess native conformation, only one derived from the carboxyl terminal showed inhibitory effect to the sperm‐zona binding during in vitro fertilization. This phenomenon could not be explained by enhanced acrosomal exocytosis rate, in that the acrosomal reaction assay demonstrated its inability to induce the acrosomal reaction. Our results suggest that the carboxyl terminal of mZP3 polypeptide backbone interacts with sperm and such interaction plays a significant role in sperm‐zona binding, ultimately successful fertilization. Mol. Reprod. Dev. 74: 1327–1336, 2007. © 2007 Wiley‐Liss, Inc.
A natural neighbour method for linear elastic problems based on Fraeijs de Veubeke variational principle
Authors: Cescotto Serge , Li Xiang 
Published: February 2007

AbstractThe natural neighbour method can be considered as belonging to the meshless methods. Classically, the development of this method is based on the virtual work principle. In the present paper, we use the natural neighbour method for 2D domains starting from the Fraeijs de Veubeke variational principle and we approximate separately the displacement field, the stress field and the strain field: the assumed strains and the assumed stresses are constant over each Voronoi cell, the assumed surface reactions are constant along the edge where the displacements are imposed, while the assumed displacements are interpolated by Laplace interpolants. In the absence of body forces, it is shown that the calculation of integrals on the area of the solid domain can be avoided: only integrals on the edges of the Voronoi cells are necessary. On the other hand, displacements can be imposed in the average sense on some boundaries of the domain. Patch tests and some applications in the elastic domain are given in the paper and show the effectiveness of the method. Copyright © 2007 John Wiley & Sons, Ltd.
On the solution of generalized non‐linear complex‐symmetric eigenvalue problems
Authors: Dumont N. A. 
Published: February 2007

AbstractThis paper brings an attempt toward the systematic solution of the generalized non‐linear, complex‐symmetric eigenproblem (K0−iωC1−ω2M1−iω3C2−ω4M2−···)ϕ=0, with real, symmetric matrices K0, Cj, Mj ε Rn×n, which are associated with the dynamic governing equations of a structure submitted to viscous damping, as laid out in the frame of an advanced mode superposition technique. The problem can be restated as (K(ω)−ωM(ω))ϕ=0, where K(ω)=K and M(ω)=M are complex‐symmetric matrices given as power series of the complex eigenfrequencies ω, such that, if (ω, ϕ) is a solution eigenpair, ϕTM(ω)ϕ=1 and ϕTK(ω)ϕ=ω. The traditional Rayleigh quotient iteration and the more recent Jacobi–Davidson method are outlined for complex‐symmetric linear problems and shown to be mathematically equivalent, both with asymptotically cubic convergence. The Jacobi–Davidson method is more robust and adequate for the solution of a set of eigenpairs. The non‐linear eigenproblem subject of this paper can be dealt with in the exact frame of the linear analysis, thus also presenting cubic convergence. Two examples help us to visualize some of the basic concepts developed. Three more examples illustrate the applicability of the proposed algorithm to solve non‐linear problems, in the general case of underdamping, but also for overdamping combined with multiple and close eigenvalues. Copyright © 2007 John Wiley & Sons, Ltd.
Local government reform in Jamaica and Trinidad: a policy dilemma
Authors: Schoburgh Eris D. 
Published: February 2007

AbstractIssues of local governance have dominated Caribbean policy agenda for the past two decades, prompting considerable thought and action on local government reform by scholars, local government practitioners and policy makers, alike. No reforms have been as ubiquitous as those of local government. Permitted by an international reformist agenda, local government reform policy is linked positively to efforts to redress incapacities of public management and administration. This article examines conceptual and empirical issues relating to implementation of local government reform in two Caribbean countries, Jamaica and Trinidad. It analyses how the vision for local governance is articulated through specific reform taxonomies and argues that, although local government reform is normatively a policy aimed at fundamental changes in intergovernmental relations, in Jamaica and Trinidad reform has led merely to adjustments in the internal administration of local government. Copyright © 2007 John Wiley & Sons, Ltd.