bluuebunny/crossref_metadata_2025_split huggingface dataset:
The refinement of renewable resources: New important derivatives of fatty acids and glycerol
Authors: Behr Arno , Gomes Jessica Pérez 
Published: January 2010

AbstractDuring the last years, the industrial significance of renewable resources has highly increased. The ever‐growing use of fossil resources for energy consumption, polymers, fine chemicals and pharmaceuticals and the therefore steadily increasing price favour the substitution of oil and gas by renewable resources. Here, especially products of catalytic functionalisations of vegetable fats and oils such as rapeseed oil, sunflower oil, palm oil or coconut oil play a decisive role. The present article gives a survey of several important catalytic functionalisations of fatty compounds and glycerol resulting in new attractive products. With their emerging properties, they could find a rapid introduction into the chemical market. Particularly the functionalisations via heterogeneous and homogeneous catalysis, like additions, reductions, oxidations and metathesis reactions, will be presented.
Biocompatible surfactants from renewable hydrophiles
Authors: Infante Ma Rosa , Pérez Lourdes , Morán Ma Carmen , Pons Ramon , Mitjans Montserrat , Vinardell Ma Pilar , Garcia Ma Teresa , Pinazo Aurora 
Published: January 2010

AbstractSignificant advances made by the authors in the field of cationic surfactants derived from arginine and lysine hydrophilic sources of different structure are reviewed. Linear, gemini and glycerolipid‐like structures with polar groups consisting of Arg or Lys amino acids are described. Our multidisciplinary approach includes design, synthesis, adsorption at interfaces and self‐assembly behavior, antimicrobial activity, and studies of biocompatibility including ecotoxicity, biodegradability and irritation effects. Considering the green chemistry principles, the synthesis contemplates the preparation of more efficient and safer surfactants using renewable raw materials for the synthesis of surfactants: proteins, peptides, amino acids and triacylglycerols, using biocatalysis as condensating methodology, and designing for biodegradation. Also in order to increase the efficiency of these compounds, a complete characterization including self‐assembly, ecotoxicity, biodegradability, and studies of mechanisms of toxicity has been carried out. The structure of the surfactant molecule affects micellization and not the nature of the polar head (Arg or Lys). The critical micelle concentrations of the gemini surfactants are three orders of magnitude lower than the linear ones for the same alkyl chain length. The presence of a cationic charge in the amino acid provides antimicrobial activity to these compounds.
Surfactants from oleic, erucic and petroselinic acid: Synthesis and properties
Authors: Dierker Markus , Schäfer Hans J. 
Published: January 2010

AbstractMost surfactants are based on C12 and C14 chains from fatty acids and contain alkanols obtained from ethylene. Readily available fatty acids with C18 and C22 chains are barely used due to their lower water solubility and less suitable structure for micelle formation. To overcome these deficiencies, we attached polar groups to terminal and/or internal positions of oleic, petroselinic and erucic acid. Internal diols were prepared by epoxidation and acid‐catalyzed ring opening or by bishydroxylation with catalytic amounts of osmium tetroxide. Terminal alcohols were prepared by reduction of the methyl esters. For the synthesis of the non‐ionic surfactants, the alcohols were reacted with the p‐toluenesulfonates of di‐, tri‐ and tetraethyleneglycols or the epoxide ring was opened with the corresponding oligoethyleneglycols. This way, ethoxylates free of homologues were obtained. Sodium sulfate surfactants were prepared by reacting the mono‐, di‐ and triols with different equivalents of chlorosulfonic acid. From the purified products, the spectroscopic and the surfactant properties were determined. The latter are in many cases equal or better than those of commercial ionic and non‐ionic surfactants based on C12 and C14 carbon chains.
Castor oil as a renewable resource for the chemical industry
Authors: Mutlu Hatice , Meier Michael A. R. 
Published: January 2010

AbstractCastor oil is, as many other plant oils, a very valuable renewable resource for the chemical industry. This review article provides an overview on this specialty oil, covering its production and properties. More importantly, the preparation, properties and major application possibilities of chemical derivatives of castor oil are highlighted. Our discussion focuses on application possibilities of castor oil and its derivatives for the synthesis of renewable monomers and polymers. An overview of recent developments in this field is provided and selected examples are discussed in detail, including the preparation and characterization of castor oil‐derived polyurethanes, polyesters and polyamides.
Esters of calendula oil and tung oil as reactive diluents for alkyd resins
Authors: Biermann Ursula , Butte Werner , Holtgrefe Ralf , Feder Willi , Metzger Jürgen O. 
Published: January 2010

AbstractA simple protocol for the transesterification of highly unsaturated vegetable oils such as calendula oil and tung oil, catalyzed by sodium methoxide, is described. Calendula oil contained about 59–65% of calendic acid (8,10‐trans,12‐cis‐octadecatrienoic acid) (1a), and tung oil about 84% of α‐eleostearic acid (9‐cis,11,13‐trans‐octadecatrienoic acid) (2a). Transesterifications of calendula oil with alcohols such as methanol, ethanol, and isopropanol give the respective calendula oil esters, which were tested as reactive diluents for alkyd resins in coating formulations. Especially ethyl and isopropyl calendula oil esters showed good properties, including low viscosity and good drying performance. Furthermore, a shortening of the drying time of about 35–40% compared to conventionally prepared formulations was achieved. Analogously, the respective esters of tung oil were synthesized and used as reactive diluent.
Biogenic origin of coastal honeycomb weathering
Authors: Mustoe George E. 
Published: January 2010

AbstractHoneycomb weathering occurs in two environments in Late Cretaceous and Eocene sandstone outcrops along the coastlines of south‐west Oregon and north‐west Washington, USA, and south‐west British Columbia, Canada. At these sites honeycomb weathering is found on subhorizontal rock surfaces in the intertidal zone, and on steep faces in the salt spray zone above the mean high tide level. In both environments, cavity development is initiated by salt weathering. In the intertidal zone, cavity shapes and sizes are primarily controlled by wetting/drying cycles, and the rate of development greatly diminishes when cavities reach a critical size where the amount of seawater left by receding tides is so great that evaporation no longer produces saturated solutions. Encrustations of algae or barnacles may also inhibit cavity enlargement. In the supratidal spray zone, honeycomb weathering results from a dynamic balance between the corrosive action of salt and the protective effects of endolithic microbes. Subtle environmental shifts may cause honeycomb cavity patterns to continue to develop, to become stable, or to coalesce to produce a barren surface. Cavity patterns produced by complex interactions between inorganic processes and biologic activity provide a geological model of ‘self‐organization’. Surface hardening is not a factor in honeycomb formation at these study sites. Salt weathering in coastal environments is an intermittently active process that requires particular wind and tidal conditions to provide a supply of salt water, and temperature and humidity conditions that cause evaporation. Under these conditions, salt residues may be detectable in honeycomb‐weathered rock, but absent at other times. Honeycomb weathering can form in only a few decades, but erosion rates are retarded in areas of the rock that contain cavity patterns relative to adjacent non‐honeycombed surfaces. Copyright © 2010 John Wiley & Sons, Ltd.
Mapping hydraulic biotopes using terrestrial laser scan data of water surface properties
Authors: Milan D.J. , Heritage G.L. , Large A.R.G. , Entwistle N.S. 
Published: January 2010

AbstractFor more than a decade, habitat mapping using biotopes (in‐channel hydraulically‐defined habitats) has underpinned aquatic conservation in the UK through (a) providing baseline information on system complexity and (b) allowing environmental and ecological change to be monitored and evaluated. The traditional method used is the subjective river habitat or corridor survey. This has recently been revised to include the floodplain via GeoRHS, but issues still exist concerning development of a national database due to the labour intensive nature of the data collection, subjectivity issues between samplers, temporal changes, the fuzzy nature of perceived habitats and habitat boundaries. This paper takes an innovative approach to biotope definition using high resolution spatial data to define water surface roughness for two representative reaches of the River South Tyne, Cumbria, and the River Rede, Northumberland, UK. Data was collected using a terrestrial laser scanner (TLS) and hydraulic variability simply expressed through assigning a local standard deviation value to a set of adjacent water surface values. Statistical linkage of these data with biotope locations defined visually in the field allowed complete mapping of the surveyed reach defining habitat and biotope areas to the fine scale resolution of the TLS data. Despite issues of data loss due to absorption and transmission through the water, the reflected signal generated an extremely detailed and objective map of the water surface roughness, which may be compared with known biotope locations as defined by visual identification in the field. The TLS accuracy achieved in the present study is comparable with those obtained using hyperspectral imagery: with 84% of the pool/glide/marginal deadwater amalgamated biotope, 88% of riffles, 57% of runs and 50% of the amalgamated cascade/rapid biotope successfully plotted. It is clear from this exercise that biotope distribution is more complex than previously mapped using subjective techniques, and based upon the water surface roughness delimiters presented in this study, the amalgamation of pools with glides and marginal deadwaters, riffles with unbroken standing waves, and cascades with rapids, is proposed. Copyright © 2010 John Wiley & Sons, Ltd
Comparison of LiDAR waveform processing methods for very shallow water bathymetry using Raman, near‐infrared and green signals
Authors: Allouis Tristan , Bailly Jean‐Stéphane , Pastol Yves , Le Roux Catherine 
Published: January 2010

AbstractAirborne light detection and ranging (LiDAR) bathymetry appears to be a useful technology for bed topography mapping of non‐navigable areas, offering high data density and a high acquisition rate. However, few studies have focused on continental waters, in particular, on very shallow waters (<2 m) where it is difficult to extract the surface and bottom positions that are typically mixed in the green LiDAR signal. This paper proposes two new processing methods for depth extraction based on the use of different LiDAR signals [green, near‐infrared (NIR), Raman] of the SHOALS‐1000T sensor. They have been tested on a very shallow coastal area (Golfe du Morbihan, France) as an analogy to very shallow rivers. The first method is based on a combination of mathematical and heuristic methods using the green and the NIR LiDAR signals to cross validate the information delivered by each signal. The second method extracts water depths from the Raman signal using statistical methods such as principal components analysis (PCA) and classification and regression tree (CART) analysis. The obtained results are then compared to the reference depths, and the performances of the different methods, as well as their advantages/disadvantages are evaluated. The green/NIR method supplies 42% more points compared to the operator process, with an equivalent mean error (−4·2 cm verusu −4·5 cm) and a smaller standard deviation (25·3 cm verusu 33·5 cm). The Raman processing method provides very scattered results (standard deviation of 40·3 cm) with the lowest mean error (−3·1 cm) and 40% more points. The minimum detectable depth is also improved by the two presented methods, being around 1 m for the green/NIR approach and 0·5 m for the statistical approach, compared to 1·5 m for the data processed by the operator. Despite its ability to measure other parameters like water temperature, the Raman method needed a large amount of reference data to provide reliable depth measurements, as opposed to the green/NIR method. Copyright © 2010 John Wiley & Sons, Ltd.
Coordination of size and number of excitatory and inhibitory synapses results in a balanced structural plasticity along mature hippocampal CA1 dendrites during LTP
Authors: Bourne Jennifer N. , Harris Kristen M. 
Published: January 2010

AbstractEnlargement of dendritic spines and synapses correlates with enhanced synaptic strength during long‐term potentiation (LTP), especially in immature hippocampal neurons. Less clear is the nature of this structural synaptic plasticity on mature hippocampal neurons, and nothing is known about the structural plasticity of inhibitory synapses during LTP. Here the timing and extent of structural synaptic plasticity and changes in local protein synthesis evidenced by polyribosomes were systematically evaluated at both excitatory and inhibitory synapses on CA1 dendrites from mature rats following induction of LTP with theta‐burst stimulation (TBS). Recent work suggests dendritic segments can act as functional units of plasticity. To test whether structural synaptic plasticity is similarly coordinated, we reconstructed from serial section transmission electron microscopy all of the spines and synapses along representative dendritic segments receiving control stimulation or TBS‐LTP. At 5 min after TBS, polyribosomes were elevated in large spines suggesting an initial burst of local protein synthesis, and by 2 h only those spines with further enlarged synapses contained polyribosomes. Rapid induction of synaptogenesis was evidenced by an elevation in asymmetric shaft synapses and stubby spines at 5 min and more nonsynaptic filopodia at 30 min. By 2 h, the smallest synaptic spines were markedly reduced in number. This synapse loss was perfectly counterbalanced by enlargement of the remaining excitatory synapses such that the summed synaptic surface area per length of dendritic segment was constant across time and conditions. Remarkably, the inhibitory synapses showed a parallel synaptic plasticity, also demonstrating a decrease in number perfectly counterbalanced by an increase in synaptic surface area. Thus, TBS‐LTP triggered spinogenesis followed by loss of small excitatory and inhibitory synapses and a subsequent enlargement of the remaining synapses by 2 h. These data suggest that dendritic segments coordinate structural plasticity across multiple synapses and maintain a homeostatic balance of excitatory and inhibitory inputs through local protein‐synthesis and selective capture or redistribution of dendritic resources. ©2010 Wiley‐Liss, Inc.
Cannabinoids alter spontaneous firing, bursting, and cell synchrony of hippocampal principal cells
Authors: Goonawardena Anushka V. , Riedel Gernot , Hampson Robert E. 
Published: January 2010

AbstractBoth natural and synthetic cannabinoid receptor (e.g., CB1) agonists such as Δ9‐THC, WIN 55,212‐2 (WIN‐2), and HU‐210 disrupt spatial cognition presumably through the inhibition of synchrony of hippocampal ensemble firing to task‐related events. Although the CB1 receptor agonist CP 55,940 also disrupts the synchronous firing of hippocampal neurons, it does not seem to affect the average firing rate. This difference is not readily explained by the chemical structure and pharmacology of the different compounds thus warranting a more detailed examination into (i) how other cannabinoids affect the spontaneous firing, bursting, and cell synchrony of hippocampal principal cells located in CA3 and CA1 subfields, and (ii) whether these effects are indeed mediated through CB1 receptors, which will be explored by the selective antagonist AM‐251. Male Long‐Evans rats surgically implanted with multielectrode arrays to hippocampal CA3 and CA1 were anesthetized and principal cells discharging at 0.25–6.0 Hz were isolated and “tracked” following the systemic administration of Tween‐80, Δ9‐THC (1 or 3 mg/kg) or WIN‐2 (1 mg/kg) or HU‐210 (100 μg/kg), and 1.5 mg/kg AM‐281. All cannabinoids except for 1 mg/kg Δ9‐THC reliably reduced average firing rates and altered “burst” characteristics, which were reversible with AM‐281 for Δ9‐THC and WIN‐2 but not for HU‐210. In addition, all cannabinoids disrupted intrasubfield and intersubfield ensemble synchrony of pyramidal cells, which is an effect insensitive to AM‐281 and thus unlikely to be CB1 mediated. We consider these cannabinoid effects on spike timing and firing/bursting of principal hippocampal neurons carried by CB1 and non‐CB1 receptors to be physiological underpinnings of the cognitive impairments inherent to cannabinoid exposure. © 2010 Wiley‐Liss, Inc.
Getting the most from MBA internships: Promoting intern learning and job acceptance
Authors: Beenen Gerard , Rousseau Denise M. 
Published: January 2010

AbstractMBA internships are commonly used for training and recruiting management talent. Yet, research overlooks what makes them effective. A longitudinal study investigates the relationships that goal clarity, autonomy, and prior experience have with MBA intern learning and job acceptance intentions. Results show learning partially mediates the relationship of goal clarity to job acceptance intentions, and that less experienced MBA interns learn more under conditions of high goal clarity and low autonomy (i.e., when their roles are more structured). We discuss how role structures and learning can inform effective training and recruiting of interns, and management of short‐term workers in general. © 2010 Wiley Periodicals, Inc.
Understanding of the Common Land Model performance for water and energy fluxes in a farmland during the growing season in Korea
Authors: Choi Minha , Lee Seung Oh , Kwon Hyojung 
Published: January 2010

AbstractThe Common Land Model (CLM) is one of the most widely used land surface models (LSMs) due to the practicality of its simple parameterization scheme and its versatility in embracing a variety of field datasets. The improved assessment of land surface water and energy fluxes using CLM can be an alternative approach for understanding the complex land–atmosphere interactions in data‐limited regions. The understanding of water and energy cycles in a farmland is crucial because it is a dominant land feature in Korea and Asia. However, the applications of CLM to farmland in Korea are in paucity. The simulations of water and energy fluxes by CLM were conducted against those from the tower‐based measurements during the growing season of 2006 at the Haenam site (a farmland site) in Korea without optimization. According to the International Geosphere–Biosphere Programme (IGBP) land cover classification, a homogeneous cropland was selected initially for this study. Although the simulated soil moisture had a similar pattern to that of the observed, the former was relatively drier (at 0·1 m3 m−3) than the latter. The simulated net radiation showed good agreement with the observed, with a root mean squared error (RMSE) of 41 W m−2, whereas relatively large discrepancies between the simulation and observation were found in sensible (RMSE of 66 W m−2) and latent (RMSE of 60 W m−2) heat fluxes. On the basis of the sensitivity analysis, soil moisture was more receptive to land cover and soil texture parameterizations when compared to soil temperature and turbulent fluxes. Despite the uncertainty in the predictive capability of CLM employed without optimization, the initial performance of CLM suggests usefulness in a data‐limited heterogeneous farmland in Korea. Further studies are required to identify the controls on water and energy fluxes with an improved parameterization. Copyright © 2010 John Wiley & Sons, Ltd.
Cell‐penetrating peptides: Nanocarrier for macromolecule delivery in living cells
Authors: Chugh Archana , Eudes François , Shim Youn‐Seb 
Published: January 2010

AbstractNovel classes and applications of cell‐penetrating peptides (CPPs) are being constantly discovered since they were first identified 2 decades ago. These short cationic peptides (nanomolecules) either by covalent binding or by noncovalent binding can traverse cell membranes and deliver a variety of molecules that are unable to overcome the permeability barrier in their own capacity. The ability of the CPPs to deliver variety of macromolecules, such as oligonucleotides, therapeutic drugs, proteins, and medical imaging agents, by forming nanoparticulate carriers in a range of cells has led them to emerge as a potential tool for both macromolecule delivery application and to gain insight into the fundamentals of mechanism of cellular uptake across the plasma membrane. This review explores the recent advances, challenges, and future prospects in the field of CPP‐mediated cargo delivery in mammalian and plant cells. Studies have been conducted into the peptide chemistry and stability of CPP‐macromolecular complexes. Most of the CPPs have been shown to be nontoxic and do not interfere with the functionality of the macromolecules delivered across the cell membrane. The mechanism of uptake of CPP‐cargo complexes and the uptake of CPPs alone across the plasma membrane remains unresolved. As the world of CPPs is rapidly advancing in both mammalian and plant system, there is a promising future for the various applications of transduction and transfection into intact cells. © 2010 IUBMB IUBMB Life, 62(3): 183–193, 2010
Worms to the rescue: Can worm glycans protect from autoimmune diseases?
Authors: Kuijk Loes M. , van Die Irma 
Published: January 2010

AbstractAutoimmune and autoinflammatory diseases represent a significant health burden, especially in Western societies. For the majority of these diseases, no cure exists. Recently, research on parasitic worms (helminths) has demonstrated great potential for whole worms, their eggs or their excretory/secretory proteins in down‐regulating inflammatory responses both in vitro and in vivo, in various disease models and, in some cases, even in clinical trials. The worms are thought to induce Th2 and regulatory T cells, interfere with Toll‐like receptor (TLR) signaling and to down‐regulate Th17 and Th1 responses. The molecular mechanisms underlying the worms' ability to modulate the host immune response are not well understood, and many hypotheses have been proposed to explain the observed immune modulation. Increasing evidence suggests that carbohydrate structures (glycans), for example, phosphorylcholine‐modified glycans or Galβ1‐4(Fucα1‐3)GlcNAc‐ (Lewis X, LeX) containing glycans, expressed by the worms contribute to these modulating properties by their interaction with antigen presenting cells. Helminths express a broad variety of protein‐ and lipid‐linked glycans on their surface and on secretory products. These glycans differ in amount and composition and several of these structures are species specific. However, worms also express glycan antigens that are found in a wide variety of different species. Some of these “common” worm glycans are particularly interesting with regard to regulating host responses, because they have the potential to interact with C‐type lectins on dendritic cells and thereby may interfere with T‐cell polarization. Helminths and helminth‐derived molecules form a novel and promising group of therapeutics for autoinflammatory diseases. However, much has to be learned about the molecular mechanisms behind the helminth‐mediated antiinflammatory properties. This review will describe some of the emerging evidence in selected disease areas as well as discuss the putative role of glycans in helminth‐mediated immunosuppression. © 2010 IUBMB IUBMB Life, 62(4): 303–312, 2010