bluuebunny/crossref_metadata_2025_split huggingface dataset:
Superparamagnetic Composites: Magnetism with No Memory
Authors: Tartaj Pedro 
Published: December 2008

AbstractThe past five years have witnessed a renewed interest in the field of superparamagnetic composites driven by both the excitement of understanding individual and cooperative properties at the nanoscale and the potential for the use of such composites in catalysis, magneto‐optics, and specially bioscience, where new applications are emerging. The basis for the interest in superparamagnetic composites lies in the combination of superparamagnetic nanoparticles with matrixes of different nature. Superparamagnetic nanoparticles endow the composites with adequate magnetic functionality (guiding, monitoring, heating), while the matrixes improve stability (sedimentation, shielding), chemical functionality, and compatibility (hydrophobicity or hydrophilicity, toxicity,stealth). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Louis Fieser: An Organic Chemist in Peace and War
Authors: Lenoir Dieter , Tidwell Thomas T. 
Published: December 2008

AbstractLouis Frederick Fieser (1899–1977) was an prominent figure among organic chemists of the mid‐20thcentury, identified today forReagents for Organic Synthesis, co‐authored with his wife Mary Fieser, and now available electronically. Fieser was first known for his prolific research efforts in quinones, polycyclic aromatics, and steroids, and was also a leading educator and public servant. His activities included not only major achievements in cancer research and cancer prevention through the suppression of smoking, but also participation in war research and the invention of napalm, which are part of his legacy.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Screening the Structural Space of Bicyclo‐DNA: Synthesis and Thermal Melting Properties of bc4,3‐DNA
Authors: Stauffiger Andrea , Leumann Christian J. 
Published: December 2008

AbstractIn attempts to screen the structural and functional properties of bicyclo‐DNA, in which the ribose C(3′) and C(5′) centers are integrated into an additional five‐membered carbocyclic ring ([3.3.0]‐series) we have now synthesized and investigated a ring enlarged analogue in which C(5′) and C(3′) are spanned by a six‐membered carbocyclic ring ([4.3.0]‐series). The synthesis of the corresponding bc4,3‐T nucleoside 13 was performed in 12 steps by starting from known allyl furanose 1. X‐ray analysis of its benzyl protected precursor 12 showed the cyclohexane ring to adopt a chair conformation with the O(5′) substituent in an axial position. The furanose part shows clearly S‐type sugar pucker. This nucleoside was converted into the corresponding phosphoramidite building block 15 and incorporated into oligodeoxynucleotides by standard phosphoramidite chemistry. The thermal stabilities of oligonucleotides with single or double incorporations of bc4,3‐T residues, paired to complementary DNA or RNA, were found to be similar to those of unmodified oligonucleotides (–2.3 to +0.7 °C per modification) and to those with the known bc‐T modifications. We also found that mismatch discrimination in the bc4,3‐T series was similar to that of the natural series but less discriminative in comparison to the known bc‐T series.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Chlorophyll Catabolites – Chemical and Structural Footprints of a Fascinating Biological Phenomenon (Eur. J. Org. Chem. 1/2009)
Authors: Moser Simone , Müller Thomas , Oberhuber Michael , Kräutler Bernhard 
Published: December 2008

AbstractThe cover picture shows a ripe apple and a yellow leaf from an apple tree. In ripening fruit and in leaf senescence, the green plant pigment chlorophyll is degraded to tetrapyrrolic, colourless catabolites (so‐called NCCs), such as the one described by the structural formula given. The present knowledge on the occurrence and structural properties of chlorophyll catabolites in higher plants is outlined in the Microreview by B. Kräutler et al. on p. 21 f. Picture courtesy of Dr. Thomas Müller, University of Innsbruck, Austria.
Microwave‐Assisted Electroanalysis: A Review
Authors: Cutress Ian J. , Marken Frank , Compton Richard G. 
Published: December 2008

AbstractMicrowave‐assisted electrochemistry is critically discussed with a focus on the fundamental aspects of the processes involved and its applications in electroanalysis. The concept of direct and nondirect heated electrodes is discussed, and simulation work is evaluated. Microwave‐assisted electrochemistry predominantly results in higher current responses (up to 2 magnitudes higher) due to increased temperature and mass transport to the active electrodes. Temperature gradients at microwave‐affected electrodes may exceed 105 K/cm, with temperature hotspots found in the thin diffusion layers set up at ultramicroelectrodes. Research into microwave‐assisted electroanalysis can lead to enhanced capillary electrophoresis detection, improved stripping voltammetry and development of new high temperature methods.
New taxa of Allium L. subg. Allium (Alliaceae) from Tajikistan and Uzbekistan
Authors: Fritsch R. M. , Khassanov F. O. 
Published: December 2008

AbstractThe alliances of Allium filidens Regel and A. brevidens Vved. were taxonomically revised. Three subspecies were recognized for A. filidens. The widely distributed typical subspecies is characterized by thick reticulate bulb tunics, relatively short leaf sheathes, and whitish tepals with greenish or bluish median veins. Subspecies ugamicum (Vved.) R.M.Fritsch & F.O.Khass. occurring in Chatkal, Pskem, and Ugam mountain ranges E and NE of Tashkent, has delicate, reticulate bulb tunics, relatively longer leaf sheathes, and faintly blue to violet flowers. Subspecies mogianense R.M.Fritsch & F.O.Khass. occupies a small area of distribution in western Hissar mountain range and differs from subsp. ugamicum by greenish tepals with broad green median veins. A key for determination of these subspecies is given. Allium brevidens subsp. pshikharvium R.M.Fritsch & F.O.Khass. was newly described from higher altitudes of Tajik Vanch, Darvaz, and Peter I. mountain ranges. It differs from the typical subspecies by larger scapes, denser inflorescences, green (not yellowish) tepals with dark‐green median veins and violet (not purplish) filaments. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical simulation of tangentially injected turbulent swirling flow in a divergent tube
Authors: Guo Hui‐Fen , Chen Zhi‐Yong 
Published: December 2008

AbstractThis paper studies the properties of turbulent swirling decaying flow induced by tangential inlets in a divergent pipe using the realizable k–ε turbulence model and discusses the effects of the injector pressure and injection position. The results of transient solutions show that both the recirculation zone near the wall in upstream of the injectors and the vortex breakdown in downstream of the injectors increase in size during the whole period. A nearly axisymmetric conical breakdown is formed and its internal structure consists of two asymmetric spiral‐like vortices rotating in opposite directions. The stagnation point shifts slowly toward the pipe outlet over time. The maxima of the three velocity components, which are located near the wall, decrease gradually with streamwise direction. It can also be inferred that Mach number approaches 1.0 near the injector outlets. The velocities increase with the increasing injector pressure. However, its increasing trend is not significant. With the increase of the injection position, vortex breakdown moves in downstream direction and the pitch along the streamwise direction increases. Copyright © 2008 John Wiley & Sons, Ltd.
Improving outcomes for workers with mental retardation
Authors: Fornes Sandra , Rocco Tonette S. , Rosenberg Howard 
Published: December 2008

AbstractThis research presents an analysis of factors predicting job retention, job satisfaction, and job performance of workers with mental retardation. The findings highlight self‐determination as a critical skill in predicting the three important employee outcomes. The study examined a hypothesized job retention model and the outcome of the three regression analyses used to test the model. The intent of the study was to develop job retention strategies that could offer rehabilitation and HR professionals a useful structure for understanding and implementing job retention interventions for people with mental retardation.
Stability of cognitive impairment in chronic schizophrenia over brief and intermediate re‐test intervals
Authors: Pietrzak Robert H. , Snyder Peter J. , Jackson Colleen E. , Olver James , Norman Trevor , Piskulic Danijela , Maruff Paul 
Published: December 2008

AbstractObjectiveThis study examined between‐ and within‐subject stability of cognitive performance in individuals with chronic schizophrenia.MethodsThirty individuals with schizophrenia and 20 healthy controls matched by age, sex, education, and estimated IQ underwent repeated cognitive assessments at baseline and 30 days using computerized tests of psychomotor function, visual attention/information processing, non‐verbal learning, and executive function.ResultsCompared to healthy controls, individuals with schizophrenia scored lower on all cognitive measures and demonstrated greater variability in cognitive performance. Within‐subject variability in cognitive performance in both the schizophrenia and healthy control groups remained stable at brief (i.e., hours) and intermediate (i.e., one month) assessments.ConclusionsThese results demonstrate the stability of between‐ and within‐subject variability in cognitive performance in schizophrenia, and suggest that variability in cognitive performance may reflect an inherent characteristic of the disorder, rather than differences in test–retest reliability/error of cognitive measures. Copyright © 2008 John Wiley & Sons, Ltd.
Changes in thaw lake drainage in the Western Canadian Arctic from 1950 to 2000
Authors: Marsh Philip , Russell Mark , Pohl Stefan , Haywood Heather , Onclin Cuyler 
Published: December 2008

AbstractThe permafrost of the Western Canadian Arctic has a very high ground ice content. As a result, the vast number of thaw lakes in this area are very sensitive to a changing climate. With thaw lakes prone to either increases in area due to thermokarst processes, or complete drainage in less than one day due to melting of channels through ice‐rich permafrost. After a lake drains, it leaves a topographic basin that is often termed a Drained Thaw Lake Basin (DTLB). An analysis of aerial photographs and topographic maps showed that 41 lakes drained in the study area between 1950 and 2000, for a rate of slightly less than one lake per year. The rate of drainage over three time periods (1950–1973, 1973–1985, 1985–2000), decreased from over 1 lake/year to approximately 0·3 lake/year. The reason for this decrease is not known, but it is hypothesized that it is related to the effect of a warming climate. There is a large spatial variation in DTLBs, with higher number of drained lakes in physiographic areas with poor drainage. It is likely that this variation is related to variations in ground ice. Although previous studies have suggested that lakes drain during periods of high water level, it is likely that a combination of a warm summer, a resulting deep active layer, and a moderately high lake level were responsible for the drainage of a lake in the study area during the summer of 1989. Although this study has documented changes in the rate of lake drainage over a 50‐year period, there is a need for further research to better understand the complex interactions between climate, geomorphology, and hydrology responsible for this change, and to further consider the potential hazard rapid lake drainage poses to future industrial or resource development in the area. Copyright © 2008 John Wiley & Sons, Ltd and Her Majesty the Queen in right of Canada. The contributions of P. Marsh, M. Russell, H. Haywood and C. Onclin belong to the Crown in right of Canada and are reproduced with the permission of Environment Canada.
Impacts of permafrost degradation on arctic river biogeochemistry
Authors: Frey Karen E. , McClelland James W. 
Published: December 2008

AbstractOver the next century, near‐surface permafrost across the circumpolar Arctic is expected to degrade significantly, particularly for land areas south of 70°N. This is likely to cause widespread impacts on arctic hydrology, ecology, and trace gas emissions. Here, we present a review of recent studies investigating linkages between permafrost dynamics and river biogeochemistry in the Arctic, including consideration of likely impacts that warming‐induced changes in permafrost may be having (or will have in the future) on the delivery of organic matter, inorganic nutrients, and major ions to the Arctic Ocean. These interacting processes can be highly complex and undoubtedly exhibit spatial and temporal variabilities associated with current permafrost conditions, sensitivity to permafrost thaw, mode of permafrost degradation (overall permafrost thaw, active layer deepening, and/or thermokarst processes), and environmental characteristics of watersheds (e.g. land cover, soil type, and topography). One of the most profound consequences of permafrost thaw projected for the future is that the arctic terrestrial freshwater system is likely to experience a transition from a surface water‐dominated system to a groundwater‐dominated system. Along with many other cascading impacts from this transition, mineral‐rich groundwater may become an important contributor to streamflow, in addition to the currently dominant contribution from mineral‐poor surface water. Most studies observe or predict an increase in major ion, phosphate, and silicate export with this shift towards greater groundwater contributions. However, we see conflicting accounts of whether the delivery of inorganic nitrogen and organic matter will increase or decrease with warming and permafrost thaw. It is important to note that uncertainties in the predictions of the total flux of biogeochemical constituents are tightly linked to future uncertainties in discharge of rivers. Nonetheless, it is clear that over the next century there will be important shifts in the river transport of organic matter, inorganic nutrients, and major ions, which may in turn have critical implications for primary production and carbon cycling on arctic shelves and in the Arctic Ocean basin interior. Copyright © 2008 John Wiley & Sons, Ltd.
The impact of a shrinking cryosphere on the form of arctic alluvial channels
Authors: McNamara James P. , Kane Douglas L. 
Published: December 2008

AbstractA shrinking cryosphere has important implications for the geomorphology of alluvial channels in arctic catchments because ice and permafrost alter the driving and resisting forces responsible for shaping local channel cross sections. For example, bedfast ice in shallow channels can suppress bedload transport during snowmelt events causing a reduction in the frequency of geomorphically effective flows, while cap ice in deeper channels can alter stream hydraulics. The impact of these local controls on catchment‐scale geomorphic patterns, however, is less certain. A case study of one arctic river in northern Alaska, USA, reveals hydraulic geometry anomalies that can be reasonably explained by the influence of ice and permafrost on local channel form. However, there is a critical lack of data from rivers wholly contained in the continuous permafrost zone preventing comprehensive understanding of how arctic rivers might respond in a shrinking cryosphere. Copyright © 2008 John Wiley & Sons, Ltd.
Elution kinetics, antimicrobial efficacy, and degradation and microvasculature of a new gentamicin‐loaded collagen fleece
Authors: Kilian Olaf , Hossain Hamid , Flesch Ingo , Sommer Ursula , Nolting Heiko , Chakraborty Trinad , Schnettler Reinhard 
Published: December 2008

AbstractManagement of bone and soft tissue infections generally includes surgical procedures as well as attendant treatment and prevention with gentamicin‐loaded fleeces. Conventional gentamicin‐containing collagen fleeces currently in use are strongly acidic and exhibit limited biocompatibility thereby adversely affecting wound healing. To improve the antibiotic delivery system, a new phosphate‐buffered, gentamicin‐loaded fleece with pH–neutral properties has been developed (Jason G®). This study aimed at comparing the elution kinetics of gentamicin release and the antimicrobial efficacy of conventional fleeces with the newly developed fleece in vitro. In addition, degradation and microvasculature of implanted fleeces were examined in a rat model and assessed using histology, as well as detection of ED‐1 and PECAM‐expression using immunohistochemistry. We show that the phosphate‐buffered fleeces have reduced release (p < 0.05) of the integrated gentamicin. However, all of the fleeces tested had a significant antimicrobial effect on the growth of Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa strains (p < 0.01). Among the fleeces tested, the new Jason G® fleece had the weakest but nevertheless sufficient antimicrobial effectiveness. Evaluation of the antibiotic effect in the prevention of an infection showed no differences between the applied fleeces. Following surgical implantation of fleece in the backs of Wistar rats we observed, on day 5 after implantation, an increase in cell infiltration and microvascularization with the phosphate‐buffered fleece as compared with conventional fleeces, which show necrotic cells on their surface. Unlike the acidic fleeces, on day 15 after implantation the pH–neutral fleece was resorbed widely. Here, we show that the new, pH–neutral, gentamicin‐containing fleece Jason G® exhibits good overall antimicrobial effectiveness against both gram‐positive and gram‐negative bacteria in vitro with improved degradation properties and microvasculature formation in vivo. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Surface properties and blood compatibility of commercially available diamond‐like carbon coatings for cardiovascular devices
Authors: Fedel Mariangela , Motta Antonella , Maniglio Devid , Migliaresi Claudio 
Published: December 2008

AbstractThe aim of this study was to determine the relationships between the surface properties and blood compatibility of in‐use diamond‐like carbon (DLC) coatings for cardiovascular components. Commercially available DLC films were characterized with respect to surface topography and wettability, protein adsorption from human plasma, and platelets adhesion/activation. Fibrinogen (Fng) and human serum albumin (HSA) adsorbed onto the sample surfaces were in particular quantified as two of the main proteins involved in blood compatibility. A low tendency of platelets to spread and form aggregates onto the DLC‐coated surfaces has been described and related to a low Fng‐to‐HSA adsorption ratio. This study provides evidence that the rapid and tenacious binding of albumin molecules to DLC materials tends to passivate the surfaces and to inhibit Fng adsorption, thus imparting thromboresistance to the carbon coatings by rendering the surfaces less adhesive and activating for platelets. Albumin preferential adsorption was ascribed to high chemical heterogeneity of the DLC sample surfaces. The DLC films tested present a favorable behavior as regards blood compatibility with respect to platelet thrombus formation by reason of their surface properties. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Analysis of bone mineral density and bone turnover in the presence of polymethylmethacrylate particles
Authors: Zilber S. , Lee S. W. , Smith R. L. , Biswal S. , Goodman S. B. 
Published: December 2008

AbstractPolymethylmethacrylate (PMMA) particles generated from joint arthroplasties appear to contribute to aseptic implant loosening through inflammation‐induced periprosthetic osteolysis. However, osteolysis appears to be multifactorial; whether a direct link exists between PMMA particles and osteolysis in vivo is unproven. With the aim to define the relationship between PMMA particles and osteolysis, the authors analyzed the bone mineral density, using microCT scans preoperatively, the first day postoperatively and then every 7–10 days for 32 days, and bone turnover, using 18F‐fluoride positron emission tomography scanner (PET scan) at 8 weeks in four groups of mice that had undergone intramedullary femoral injection. The experimental group of five mice was injected with PMMA particles, and compared with two negative control groups (no injection and injection with the carrier, phosphate‐buffered saline) and one positive control group (injection of PMMA particles contaminated with endotoxin). There was no significant change in bone mineral density with addition of PMMA particles, and no evidence of osteolysis. However, bone turnover was increased in the presence of PMMA particles. Even though a direct link between PMMA particles and osteolysis was not found in the short term, PMMA particles appear to influence the regenerative capacity of bone. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Host‐derived loss of dentin matrix stiffness associated with solubilization of collagen
Authors: Carrilho Marcela R. , Tay Franklin R. , Donnelly Adam M. , Agee Kelli A. , Tjäderhane Leo , Mazzoni Annalisa , Breschi Lorenzo , Foulger Stephen , Pashley David H. 
Published: December 2008

AbstractMatrix metalloproteinases (MMPs) bound to dentin matrices are activated during adhesive bonding procedures and are thought to contribute to the progressive degradation of resin‐dentin bonds over time. The purpose of this study was to evaluate the changes in mechanical, biochemical, and structural properties of demineralized dentin treated with or without chlorhexidine (CHX), a known MMP‐inhibitor. After demineralizing dentin beams in EDTA or phosphoric acid (PA), the baseline modulus of elasticity (E) of each beam was measured by three‐point flexure. Specimens were pretreated with water (control) or with 2% CHX (experimental) and then incubated in artificial saliva (AS) at 37°C for 4 weeks. The E of each specimen was remeasured weekly and, the media was analyzed for solubilized dentin collagen at first and fourth week of incubation. Some specimens were processed for electron microscopy (TEM) immediately after demineralization and after 4 weeks of incubation. In EDTA and PA‐demineralized specimens, the E of the control specimens fell (p < 0.05) after incubation in AS, whereas there were no changes in E of the CHX‐pretreated specimens over time. More collagen was solubilized from PA‐demineralized controls (p < 0.05) than from EDTA‐demineralized matrices after 1 or 4 weeks. Less collagen (p < 0.05) was solubilized from CHX‐pretreated specimens demineralized in EDTA compared with PA. TEM examination of control beams revealed that prolonged demineralization of dentin in 10% PA (12 h) did not denature the collagen fibrils. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
GridMAT‐MD: A grid‐based membrane analysis tool for use with molecular dynamics
Authors: Allen William J. , Lemkul Justin A. , Bevan David R. 
Published: December 2008

AbstractGridMAT‐MD is a new program developed to aid in the analysis of lipid bilayers from molecular dynamics simulations. It reads a GROMACS coordinate file and generates two types of data: a two‐dimensional contour plot depicting membrane thickness, and a polygon‐based tessellation of the individual lipid headgroups. GridMAT‐MD can also account for proteins or small molecules within the headgroups of the lipids, closely approximating their occupied lateral area. The program requires no installation, is fast, and is freely available. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009