bluuebunny/crossref_metadata_2025_split huggingface dataset:
Curiosity and cure: Translational research strategies for neural repair‐mediated rehabilitation
Authors: Dobkin Bruce H. 
Published: May 2007

AbstractClinicians who seek interventions for neural repair in patients with paralysis and other impairments may extrapolate the results of cell culture and rodent experiments into the framework of a preclinical study. These experiments, however, must be interpreted within the context of the model and the highly constrained hypothesis and manipulation being tested. Rodent models of repair for stroke and spinal cord injury offer examples of potential pitfalls in the interpretation of results from developmental gene activation, transgenic mice, endogeneous neurogenesis, cellular transplantation, axon regeneration and remyelination, dendritic proliferation, activity‐dependent adaptations, skills learning, and behavioral testing. Preclinical experiments that inform the design of human trials ideally include a lesion of etiology, volume and location that reflects the human disease; examine changes induced by injury and by repair procedures both near and remote from the lesion; distinguish between reactive molecular and histologic changes versus changes critical to repair cascades; employ explicit training paradigms for the reacquisition of testable skills; correlate morphologic and physiologic measures of repair with behavioral measures of task reacquisition; reproduce key results in more than one laboratory, in different strains or species of rodent, and in a larger mammal; and generalize the results across several disease models, such as axonal regeneration in a stroke and spinal cord injury platform. Collaborations between basic and clinical scientists in the development of translational animal models of injury and repair can propel experiments for ethical bench‐to‐bedside therapies to augment the rehabilitation of disabled patients. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Combinatorial treatments for promoting axon regeneration in the CNS: Strategies for overcoming inhibitory signals and activating neurons' intrinsic growth state
Authors: Benowitz Larry I. , Yin Yuqin 
Published: May 2007

AbstractIn general, neurons in the mature mammalian central nervous system (CNS) are unable to regenerate injured axons, and neurons that remain uninjured are unable to form novel connections that might compensate for ones that have been lost. As a result of this, victims of CNS injury, stroke, or certain neurodegenerative diseases are unable to fully recover sensory, motor, cognitive, or autonomic functions. Regenerative failure is related to a host of inhibitory signals associated with the extracellular environment and with the generally low intrinsic potential of mature CNS neurons to regenerate. Most research to date has focused on extrinsic factors, particularly the identification of inhibitory proteins associated with myelin, the perineuronal net, glial cells, and the scar that forms at an injury site. However, attempts to overcome these inhibitors have resulted in relatively limited amounts of CNS regeneration. Using the optic nerve as a model system, we show that with appropriate stimulation, mature neurons can revert to an active growth state and that when this occurs, the effects of overcoming inhibitory signals are enhanced dramatically. Similar conclusions are emerging from studies in other systems, pointing to a need to consider combinatorial treatments in the clinical setting. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Spatial variability of snowmelt timing from AMSR‐E and SSM/I passive microwave sensors, Pelly River, Yukon Territory, Canada
Authors: Ramage Joan M. , Apgar Jeremy D. , McKenney Rose A. , Hanna Wade 
Published: May 2007

AbstractSpring snow melt run‐off in high latitude and snow‐dominated drainage basins is generally the most significant annual hydrological event. Melt timing, duration, and flow magnitude are highly variable and influence regional climate, geomorphology, and hydrology. Arctic and sub‐arctic regions have sparse long‐term ground observations and these snow‐dominated hydrologic regimes are sensitive to the rapidly warming climate trends that characterize much of the northern latitudes. Passive microwave brightness temperatures are sensitive to changes in the liquid water content of the snow pack and make it possible to detect incipient melt, diurnal melt‐refreeze cycles, and the approximate end of snow cover on the ground over large regions. Special Sensor Microwave Imager (SSM/I) and Advanced Microwave Scanning Radiometer for EOS (AMSR‐E) passive microwave brightness temperatures (Tb) and diurnal amplitude variations (DAV) are used to investigate the spatial variability of snowmelt onset timing (in two stages, ‘DAV onset’ and ‘melt onset’) and duration for a complex sub‐arctic landscape during 2005. The satellites are sensitive to small percentages of liquid water, and therefore represent ‘incipient melt’, a condition somewhat earlier than a traditional definition of a melting snowpack. Incipient melt dates and duration are compared to topography, land cover, and hydrology to investigate the strength and significance of melt timing in heterogeneous landscapes in the Pelly River, a major tributary to the Yukon River. Microwave‐derived melt onset in this region in 2005 occurred from late February to late April. Upland areas melt 1–2 weeks later than lowland areas and have shorter transition periods. Melt timing and duration appear to be influenced by pixel elevation, aspect, and uniformity as well as other factors such as weather and snow mass distribution. The end of the transition season is uniform across sensors and across the basin in spite of a wide variety of pixel characteristics. Copyright © 2007 John Wiley & Sons, Ltd.
Simulation and parameterization of superimposed ice formation
Authors: Bøggild Carl Egede 
Published: May 2007

AbstractIn cold Arctic snowpacks, meltwater retention is a significant factor controlling the timing and magnitude of runoff. Meltwater percolates vertically through the snowpack until it reaches an impermeable horizon, whereupon a saturated zone is established. If the underlying media is below the freezing point, accretive ice formation takes place. This process has previously been crudely parameterized or modelled numerically. Such ice is called either superimposed ice on glaciers or basal ice on bare land.Using theory derived from sea‐ice formation, an analytical solution to basal ice growth is proposed. Results are compared against growth rates derived from numerical modelling. In addition, model results are compared to field observations of ice temperatures. The analytical solution is further extended to account for the temperature gradient inside the underlying media and the variable thermal properties of the underlying media.In the analysis, observations and references have predominantly relied on knowledge from glaciers. However, the process of accretive ice growth is equally important in seasonal snow packs with a cold snow‐ground interface and on Arctic sea ice where the ice‐snow interface is well below freezing point. The simplification of this accretive ice growth problem makes the solution attractive for incorporation in large‐scale cryospheric models. Copyright © 2007 John Wiley & Sons, Ltd.
Bladder cancers respond to intravesical instillation of (HAMLET human α‐lactalbumin made lethal to tumor cells)
Authors: Mossberg Ann‐Kristin , Wullt Björn , Gustafsson Lotta , Månsson Wiking , Ljunggren Eva , Svanborg Catharina 
Published: May 2007

AbstractWe studied if bladder cancers respond to HAMLET (human α‐lactalbumin made lethal to tumor cells) to establish if intravesical HAMLET application might be used to selectively remove cancer cells in vivo. Patients with nonmuscle invasive transitional cell carcinomas were included. Nine patients received 5 daily intravesical instillations of HAMLET (25 mg/ml) during the week before scheduled surgery. HAMLET stimulated a rapid increase in the shedding of tumor cells into the urine, daily, during the 5 days of instillation. The effect was specific for HAMLET, as intravesical instillation of NaCl, PBS or native α‐lactalbumin did not increase cell shedding. Most of the shed cells were dead and an apoptotic response was detected in 6 of 9 patients, using the TUNEL assay. At surgery, morphological changes in the exophytic tumors were documented by endoscopic photography and a reduction in tumor size or change in tumor character was detected in 8 of 9 patients. TUNEL staining was positive in biopsies from the remaining tumor in 4 patients but adjacent healthy tissue showed no evidence of apoptosis and no toxic response. The results suggest that HAMLET exerts a direct and selective effect on bladder cancer tissue in vivo and that local HAMLET administration might be of value in the future treatment of bladder cancers. © 2007 Wiley‐Liss, Inc.
Inhibition of 13‐cis retinoic acid‐induced gene expression of homeobox B7 by thalidomide
Authors: Milanović Dušan , Maier Patrick , Lohr Frank , Wenz Frederik , Herskind Carsten 
Published: May 2007

AbstractThalidomide and 13‐cis retinoic acid (RA) show anticancer effects as sole agents or in combination with other drugs. However, induction of homeobox (HOX) gene expression by 13‐cis RA may contribute to tumor progression thereby potentially limiting its efficacy. The purpose was to test if thalidomide can inhibit 13‐cis RA‐induced HOXB7 expression and whether thalidomide may enhance the antiproliferative effect of 13‐cis RA in U343MG glioblastoma cells. Quantitative real‐time PCR showed significant inhibition of 13‐cis RA‐induced HOXB7 expression by thalidomide with IC50 ∼ 0.1–0.2 μg/ml when given simultaneously with 13‐cis RA but not when administered 18h later (p < 0.0001). 13‐cis RA alone inhibited proliferation and colony formation in a concentration‐dependent manner whereas growth inhibition by thalidomide alone at 5–100 μg/ml was constant at 80–90% of controls. At 10% serum concentration, growth inhibition by a combination of the 2 drugs was additive but at 1% serum, growth inhibition was synergistic. It is concluded that thalidomide inhibits the RA‐induced HOXB7 expression in glioblastoma cells and that 13‐cis RA/thalidomide combinations can in principle enhance cytotoxicity. The improved cell kill induced by thalidomide is attributed to downregulation of growth stimulatory factors induced by 13‐cis RA. Implications for the modus operandi of thalidomide in embryogenesis are noted. © 2007 Wiley‐Liss, Inc.
Immunotherapy with dendritic cells for prostate cancer
Authors: Thomas‐Kaskel Anna‐Katharina , Waller Cornelius F. , Schultze‐Seemann Wolfgang , Veelken Hendrik 
Published: May 2007

AbstractRadical prostatectomy for prostate cancer is followed by PSA recurrence in up to 40% of patients. One third of patients with biochemical relapse progress to uncurable metastatic disease. Therefore, alternative treatment modalities are needed both in the situation of PSA recurrence and in hormone‐refractory disease. Dendritic cells (DC) are the most powerful antigen‐presenting cells, able to prime naïve T‐cells and to break peripheral tolerance and thus induce tumor immune responses. More than 400 prostate cancer patients have been treated with DC‐based immunotherapy to date, and immune responses have been reported in two‐thirds of these, resulting in clinical responses in almost half of the patients treated. Most responses, however, were modest and transient. Therefore, mechanisms of treatment failure and possibilities to improve vaccination efficacy are being discussed. © 2007 Wiley‐Liss, Inc.
An assessment of hydraulic design of trickle laterals considering effect of minor losses
Authors: Yıldırım Gürol 
Published: May 2007

AbstractThe accurate design of trickle irrigation laterals needs to determine the total energy losses that includes the pipe friction losses along the lateral line and the local pressure losses, sometimes called minor losses, due to the protrusion of emitter barbs into the flow. Evaluation of energy losses is usually carried out by assuming the hypothesis that minor losses can be neglected, even if previous experimental studies indicated that minor losses can become a significant percentage of total energy losses as a consequence of the high number of emitters installed along the lateral line. In this study, a simple analytical procedure is presented to evaluate the effect of minor losses which is characterized by a coefficient αi, expressing the amount of minor head losses as a fraction of the kinetic head, on trickle lateral design. According to both the design cases of without and including minor losses, the dimensionless design curves were developed for both the various lateral diameters and lengths. The results of two practical examples for designing either the diameter or the length indicated that, in some design cases, neglecting minor losses may lead to erroneous designs of the lateral diameter and length. This method is simple and easily adaptable to solve lateral hydraulic problems but sufficiently precise in comparison with the alternative procedures. The proposed equations are useful when applied for design and evaluation purposes and offer a practical field solution for laterals used in irrigation systems. Copyright © 2007 John Wiley & Sons, Ltd.
Understanding the risk perception of strategic opportunities: a tripartite model
Authors: Acedo Francisco J. , Florin Juan 
Published: May 2007

AbstractThis paper develops and tests a model of risk perception that draws from entrepreneurship and cognitive theories. We propose that the perception of risk associated with strategic opportunities is influenced by the individual's past experience related to the opportunity, their cognitive style for gathering and analysing relevant information and their tolerance for ambiguous situations and outcomes. Furthermore, we posit that the individual's proactive disposition is central to these relationships. The model is tested on a sample of top managers of small and medium size firms regarding their risk perception associated with international expansion. Considerable support is found for the overall model.Copyright © 2007 John Wiley & Sons, Ltd.
Radical Copolymerization of Vinylidene Fluoride with 8‐Bromo‐1H,1H,2H‐perfluorooct‐1‐ene: Microstructure, Crosslinking and Thermal Properties
Authors: Sauguet Laurent , Ameduri Bruno , Boutevin Bernard 
Published: May 2007

AbstractAn original synthesis of 8‐bromo‐1H,1H,2H‐perfluorooct‐1‐ene (BDFO) and its radical copolymerization with vinylidene fluoride (VDF), initiated by 2,5‐bis(tert‐butylperoxy)‐2,5‐dimethylhexane at 134 °C, are presented. The fluorinated bromoalkene was obtained by dehydrobromination of 1,8‐dibromo‐1H,1H,2H,2H‐perfluorooctane in a satisfactory yield. Although BDFO did not homopolymerize under radical initiation, it did copolymerize with VDF. The compositions of the resulting random type copolymers were calculated by means of 19F NMR spectroscopy and allowed the quantification of the respective amounts of both comonomers in the copolymers, showing good incorporation of the brominated monomer. Nevertheless, obtaining PVDF copolymers containing a high molar percentage of BDFO in good yields was difficult to achieve from initial molar ratios of BDFO higher than 9.2 mol‐%. Radical terpolymerization of VDF, BDFO and hexafluoropropene (HFP) was also successfully achieved. BDFO contents in these co‐ or terpolymers ranged from 3.6 to 12.2 mol‐%. The bromoalkene acted as a cure site monomer and the resulting poly(VDF‐co‐BDFO) copolymers were crosslinked via the bromine atom in the presence of a triallyl isocyanurate/peroxide system. The materials obtained led to more thermally stable copolymers than the uncured ones and their thermostabilities were compared to those of commercially available poly(VDF‐co‐HFP) copolymers crosslinked using diamines.magnified image
Liquid‐Glassy Polymer Diffusion: Effects of Liquid Molecular Weight and Temperature
Authors: Tomba J. Pablo , Arzondo Luis M. , Carella José M. , Pastor José M. 
Published: May 2007

AbstractWe examine mechanistic aspects of the diffusion between a series of liquid polystyrenes (PS) and a glassy poly(phenylene oxide) (PPO) matrix, through the use of confocal Raman microspectroscopy. The results show that the diffusion kinetics has Fickean characteristics, similar to those found in liquid‐liquid polymer diffusion. No signatures of the linear regime typical of the case‐II diffusion mechanism were found. Overall, these observations are consistent with the claim that case‐II is unlikely to occur in liquid‐glassy polymer diffusion.magnified image
Thermoresponsive Glycopolymers via Controlled Radical Polymerization
Authors: Özyürek Zeynep , Komber Hartmut , Gramm Stefan , Schmaljohann Dirk , Müller Axel H. E. , Voit Brigitte 
Published: May 2007

AbstractNew glycomonomers 3′‐(1′,2′:5′,6′‐di‐O‐isopropylidene‐α‐D‐glucofuranosyl)‐6‐methacrylamido hexanoate (MAIpGlcC5) and 3′‐(1′,2′:5′,6′‐di‐O‐isopropylidene‐α‐D‐glucofuranosyl)‐6‐methacrylamido undecanoate (MAIpGlcC10) with hydrophobic spacer units were synthesized and their homopolymers, as well as random copolymers with N‐isopropylacrylamide (NiPAAm) were prepared in varying compositions. The acidolysis of the isopropylidene protection groups of the polymers gave well‐defined sugar‐containing water‐soluble homopolymers (PMAGlcCn, n = 5, 10) and copolymers. By using the reversible addition–fragmentation chain transfer (RAFT) process, it was possible to afford these copolymers with a polydispersity index (PDI) of 1.1–1.5. Furthermore, NiPAAm homopolymers with an active chain transfer unit at the chain end could be prepared by RAFT, which were used as macro‐chain transfer agents (macro‐CTAs) to prepare a variety of sugar containing responsive block copolymers from new glycomonomers by the monomer addition concept. The cloud points of the aqueous solutions of the copolymers were strongly affected by the comonomer content, spacer chain length of the glycomonomer, and the chain architecture of the copolymers. Especially by the block copolymer concept, glycopolymers with lower critical solution temperatures (LCSTs) in the physiologically interesting range could be realized.magnified image
A Novel Synthetic Method for Well‐Defined Polymers Containing Benzotriazole and Diazobenzene Chromophores
Authors: Sun Bin , Zhu Xiulin , Zhu Jian , Cheng Zhenping , Zhang Zhengbiao 
Published: May 2007

AbstractPBHEMA was prepared by RAFT polymerization in the presence of CPDN and AIBN. Diazobenzene groups were introduced into the sidechains by post‐azo‐functionalization. The resulting polymers containing benzotriazol and azobenzene groups exhibited higher molecular weight than original polymers, narrow MWD ($\overline M _{\rm w} /\overline M _{\rm n} $ = 1.17–1.26) and adjustable degrees of functionality. Thermal stabilities and glass transition temperatures of the polymers increased with the introduction of diazo chromophores. The molecular weight of the polymer had a slight effect on the Tg of the polymer. The polymer showed partial crystallization as the diazo content increased above 36%.magnified image
Synthesis of Functionalized NMP Initiators for Click Chemistry: A Versatile Method for the Preparation of Functionalized Polymers and Block Copolymers
Authors: Fleischmann Sven , Komber Hartmut , Appelhans Dietmar , Voit Brigitte I. 
Published: May 2007

AbstractA novel NMP initiator functionalized with an alkyne group was synthesized and its polymerization behavior investigated. It was shown that the synthesized alkyne end‐functionalized polymers exhibit a linear relationship between calculated number‐averaged molecular weight and the experimental one and are characterized by a narrow molecular weight distribution. In contrast, azido end‐functionalized polymers were obtained in polymer analogue reactions. Furthermore, the alkyne end‐functionalized polymers were reacted at room temperature with different azides to introduce several functional groups. It could be shown that the polymers can be efficiently and smoothly multimodified using the Cu(I)‐catalyzed 1,3‐dipolar cycloaddition reaction between azides and alkynes (click chemistry), thus yielding macromolecules with defined molecular architecture and functionality. Furthermore, the synthesis of diblock copolymers by combining predefined polymeric fragments via click chemistry is demonstrated. In this case, the fragments could be completely linked with each other and the diblock copolymers obtained showed a narrow molecular weight distribution.magnified image
Chemical Dual‐Responsive Wettability of Superhydrophobic PANI‐PAN Coaxial Nanofibers
Authors: Zhu Ying , Feng Lin , Xia Fan , Zhai Jin , Wan Meixiang , Jiang Lei 
Published: May 2007

AbstractPANI‐PAN coaxial nanofibers have been prepared by electro‐spinning during polymerization. The surface of the resulting nanofibers is superhydrophobic with a water contact angle up to 164.5°. Conductivity of the PANI‐PAN nanofibers is about 4.3 × 10−2 S · cm−1. The superhydrophobic nanofibers show a chemical dual‐responsive surface wettability, which can be easily triggered by changing pH value or redox properties of the solution. A reversible conversion between superhydrophobicity and superhydrophilicity can be performed in a short time. The strategy used here may provide an easy method to control the wettability of smart surfaces by using properties of low‐cost functional polymers.magnified image
Electromechanical Response of Nanostructured Polymer Systems with no Mechanical Pre‐Strain
Authors: Shankar Ravi , Ghosh Tushar K. , Spontak Richard J. 
Published: May 2007

AbstractA dielectric elastomer derived from a polystyrene‐block‐poly(ethylene‐co‐butylene)‐block‐polystyrene triblock copolymer swollen with a midblock‐selective solvent is reported to show promise as a nanostructured organic actuator requiring no pre‐strain. This might provide an attractive alternative to conventional acrylic, siloxane, and polyurethane elastomers since the electromechanical properties are composition‐tunable.magnified image
Alk‐1‐ene Polymerization in the Presence of a Monocyclopentadienyl Zirconium(IV) Acetamidinate Catalyst: Microstructural and Mechanistic Insights
Authors: Busico Vincenzo , Carbonniere Philippe , Cipullo Roberta , Pellecchia Roberta , Severn John R. , Talarico Giovanni 
Published: May 2007

AbstractSuitably activated, (Cp*){N(tBu)C(Me)N(Et)}ZrMe2 is known to initiate the ‘living’ and isotactic‐selective polymerization of alk‐1‐enes, and it can be used to synthesize block copolymers and stereoblock polymers. We report a full molecular kinetic investigation of propene, but‐1‐ene, and hex‐1‐ene polymerization with a MAO‐activated catalyst system. By combining NMR microstructural polymer analysis with QM modeling of the active species, the complicated regio‐ and stereochemistry of the polyinsertion process, as well as the active chain‐transfer pathways, are investigated. The perspectives and limitations of this catalyst for application in (stereo)block polymerizations are discussed.magnified image
Stability of weak solutions to the compressible Navier–Stokes equations in bounded annular domains
Authors: Fan Jishan , Gao Hongjun 
Published: May 2007

AbstractWe prove the Lipschitz continuous dependence on initial data of global spherically symmetric weak solutions to the Navier–Stokes equations of a viscous polytropic ideal gas in bounded annular domains with the initial data in the Lebesgue spaces. Copyright © 2007 John Wiley & Sons, Ltd.
The emergence of intercommunity partnerships in the 1980s
Authors: Dodge William R. 
Published: May 2007

AbstractContraction of federal funding has been accompanied by reduced federal guidance. Local governments bear the dual burden of both designing and funding projects. The interjurisdictional partnerships of the 1980s are characterized by two things: an encouraging creativity in addressing regional issues, and a burgeoning involvement of county government as a major convening and administrative force.