bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trophic Cascades in Marine and Freshwater Plankton
Authors: Sommer Ulrich 
Published: October 2008

AbstractTransmission of top‐down control from fish to phytoplankton via crustacean mesozooplankton is a cornerstone of limnetic plankton ecology. Such trophic cascades are less frequently reported from the marine pelagic. In this article a case is made for consideration of scale issues and for the distinction between full (affecting entire trophic levels) and partial (affecting only some functional groups) trophic cascades. Partial cascades are more widespread while the full cascades are either ephemeral or depend on the suppression of compensatory growth of the predation‐resistant size‐fractions of phytoplankton. This suppression can only be achieved if there is a persistent coexistence between zooplankton feeding on different parts of the phytoplankton size spectrum. This condition is fulfilled in plankton communities where microphageous cladocerans (mainly Daphnia) and microphageous copepods coexist (many lake communities) or where krill and copepods coexist (high latitude marine communities). It is not fulfilled in many temperate and low‐latitude marine communities where copepods effectively suppress filter‐feeding appendicularians. Thus, the observed difference in the frequency of marine and limnetic pelagic cascades is considered real.Are all trophic cascades wet?Strong et al., 1992 (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Lake as a System of Differential Equations – A Paradigm for the Aquatic Ecologist of the 21st Century?
Authors: Fussmann Gregor F. 
Published: October 2008

AbstractIn the course of the 20th century limnology and oceanography have been transformed from purely descriptive disciplines to sciences that champion quantitative approaches and aim to reveal mechanistic relationships. In particular, the increasing use of mathematical formulations and models to understand lakes, streams and oceans as dynamical systems can be viewed as a paradigm shift. The mathematical‐dynamical approach is irreversibly integrated into this field and has revolutionized aquatic ecology, although its gradual and on‐going adoption is best characterized as an evolutionary process and, therefore, does not meet the criteria of the Kuhnian concept of a paradigm shift. I here show how this new approach historically emerged from the understanding of lakes and oceans as complex yet decomposable systems and describe the development of the new paradigm into the 21st century. I explain methods of validation and give examples of successful applications of the mathematical‐dynamical approach. I end with an outlook on some current, promising research directions that may influence the future path of this “ever‐evolving paradigm shift.”Seltsam ist Propheten Lied, doppelt seltsam, was geschieht Loose translation from German: “Strange is the prophet's song, twice as strange is what really happens”.
J. W. von Goethe, Weissagungen des Bakis (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Increase in cell migration and angiogenesis in a composite silk scaffold for tissue‐engineered ligaments
Authors: Seo Young‐Kwon , Yoon Hee‐Hoon , Song Kye‐Yong , Kwon Soon‐Yong , Lee Hwa‐Sung , Park Yong‐Soon , Park Jung‐Keug 
Published: October 2008

AbstractThe purpose of this study was to evaluate the biocompatibility of silk and collagen‐hyaluronan (HA) in vitro by assessing anterior cruciate ligament (ACL) cell and T‐lymphocyte cultures on scaffolds. The use of composite scaffolds as artificial ligaments in ACL reconstruction and their effects on angiogenesis were evaluated in vivo. The silk scaffold was knitted by hand and dry coated with collagen‐HA, whereas the composite silk scaffold was made by covering a silk scaffold with a lyophilized collagen‐HA substrate. The initial attachment and proliferation of human ACL cells on the composite silk scaffold was superior to the attachment and proliferation observed on the silk scaffold. The immune response was higher in both scaffolds after 72 h (p < 0.05) compared with the control culture condition without scaffolding, as assessed by T‐lymphocyte cultures in vitro. There was no significant difference in the immune response in vitro between the silk and composite silk scaffolds. Silk and composite silk scaffolds were implanted as artificial ligaments in ACLs removed from the knees of dogs, and they were harvested 6 weeks after implantation. On gross examination, the onset of an inflammatory tissue reaction, such as synovitis, was seen in both the silk scaffold and the composite silk scaffold groups. An histological evaluation of the artificial ligament implants revealed the presence of monocytes in the silk composite scaffold and the absence of giant cells in all cases. MT staining in the composite silk scaffold‐grafted group showed granulation tissue consisting of fibroblasts, lymphocytes, monocytes, and collagen fibers. In addition, CD31 staining revealed the formation of new blood vessels. On the other hand, no reparative tissues, such as blood vessels, collagen, and cells, were observed in the silk scaffold‐grafted group. These results suggest that the lyophilized collagen‐HA substrate is biocompatible in vitro and enhances new blood vessel and cell migration in vivo. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 495–503, 2009
Low‐magnitude high‐frequency vibration accelerates callus formation, mineralization, and fracture healing in rats
Authors: Leung Kwok Sui , Shi Hong Fei , Cheung Wing Hoi , Qin Ling , Ng Wai Kin , Tam Kam Fai , Tang Ning 
Published: October 2008

AbstractFracture healing is a biological regenerative process that follows a well‐orchestrated sequence. Most healing is uneventful and enhancement of normal fracture healing is not commonly done, although it is clinically important in the recovery and regain of functions after fracture. This study investigated the osteogenic effect of low‐magnitude high‐frequency vibration (LMHFV, 35 Hz, 0.3 g) on the enhancement of fracture healing in rats with closed femoral shaft fracture by comparing with sham‐treated control. Assessments with plain radiography, micro‐CT as well as histomorphometry showed that the amount of callus was significantly larger (p = 0.001 for callus area, 2 weeks posttreatment); the remodeling of the callus into mature bone was significantly faster (p = 0.039, 4 weeks posttreatment) in the treatment group. The mechanical strength of the healed fracture in the treatment group at 4 weeks was significantly greater (p < 0.001). The results showed the acceleration of callus formation, mineralization, and fracture healing in the treatment group. It is concluded that LMHFV enhances healing in the closed femoral shaft fracture in rats. The potential clinical advantages shall be confirmed in the subsequent clinical trials. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 458–465, 2009
Single high‐energy impact load causes posttraumatic OA in young rabbits via a decrease in cellular metabolism
Authors: Borrelli Joseph , Silva Matthew J. , Zaegel Melissa A. , Franz Carl , Sandell Linda J. 
Published: October 2008

AbstractArticular cartilage deterioration commonly occurs following traumatic joint injury. Patients with posttraumatic osteoarthritis (PTA) experience pain and stiffness in the involved joint causing limited mobility and function. The mechanism by which PTA occurs has not been fully delineated. The goal of this study was to determine if a single high‐energy impact load could cause the development of PTA in 3‐month‐old NZ White rabbits. Each rabbit underwent the application of a single, rapid, high‐energy impact load to the posterior aspect of their right medial femoral condyle using a previously validated mechanism. At regular intervals (0, 1, 6 months) the injured cartilage was harvested and analyzed for the presence of PTA. Each specimen was assessed histologically for cell and tissue morphology and chondrocyte metabolism, including BMP‐2 production and synthesis of extracellular matrix (type II procollagen mRNA). Cartilage from the contralateral sham limb, as well as uninjured cartilage from the experimental limb served as internal controls for each animal. Significant changes were found in the morphology of the cartilage including proteoglycan loss along with decreased BMP‐2 and type II procollagen mRNA staining. These findings confirm that a single high‐energy impact load can cause the development of PTA by disrupting the extracellular matrix and by causing a decrease in chondrocyte metabolism. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:347–352, 2009
Breeding of Pleurotus florida (oyster mushroom) for phenotypic pigmentation and high yield potential
Authors: Kaur Jatinder , Sodhi Harpreet S , Kapoor Shammi 
Published: October 2008

AbstractBACKGROUND: Cross‐hybridisation is a technique for exchange of genetic material between two compatible nuclei to develop a recombinant genome with a probable expression for a desirable trait. This technique as an example of classical genetics has been applied in a heterothallic bifactorial/tetrapolar fungus Pleurotus florida. It has worked successfully during this study in a small number of experiments.RESULTS: Fruit bodies from the Pleurotus florida PAU‐5 were allowed to shed their basidiospores on filter paper under aseptic conditions. Forty‐nine monokaryons were isolated from three spore prints, namely Ja, Jb and K. Three hundred and fifty‐six crosses were laid to result in five compatible reactions (PFJ4, PFJ9, PFJ11, PFJ13 and PFJ14). The fruit bodies of the hybrid dikaryon PFJ4 were found to show grey pigmentation. The hybrid dikaryons PFJ11 and PFJ14 grew faster in wheat straw substrate to take 39 and 41 days, respectively, for complete mycelial impregnation as compared to the parent, PAU‐5 (48 days). The dikaryon PFJ11 out‐yielded the parent by giving 34.2% biological efficiency compared to 29.8% for the parent.CONCLUSION: Through cross‐hybridisation various changes at the genetic level are possible, showing altered phenotypic expression of the characters, such as change in fruiting efficiency and variability in fruit body characteristics (e.g., pileus shape and pigmentation). This technique can also be applied to other crops to improve their yield potential and bring about desirable phenotypic changes. Copyright © 2008 Society of Chemical Industry
Effect of conjugation with glucosamine on the functional properties of lysozyme and casein
Authors: Ramezani Roghayeh , Esmailpour Mehrnaz , Aminlari Mahmoud 
Published: October 2008

AbstractBACKGROUND: Modification with carbohydrates usually changes the functional properties of proteins. Such modification might make non‐conventional food proteins (such as plant and microbial proteins) more applicable for human consumption. The purpose of this research was to conjugate glucosamine to lysozyme and casein using a water‐soluble carbodiimide and to investigate the effect of conjugation on the functional properties of these proteins.RESULTS: Glycosylation with glucosamine converted casein to high‐molecular‐weight species which appeared as diffuse bands in sodium dodecyl sulfate polyacrylamide gel electrophoresis. Approximately 2 and 0.11 mol of glucosamine was attached to 1 mol of casein and lysozyme respectively. Both conjugated proteins exhibited improved solubility at different pHs (3 and 6) and different temperatures (25, 45 and 60 °C), increased heat stability and better emulsifying activity, emulsion stability and foaming capacity compared with the unmodified proteins (P < 0.05).CONCLUSION: These changes might increase the applicability of lysozyme as a natural antimicrobial and casein as a protein ingredient in different food systems. Copyright © 2008 Society of Chemical Industry
A Facile Route for Regioselective Conjugation of Organo‐Soluble Polymers onto Chitosan
Authors: Cai Guoqiang , Jiang Hongliang , Tu Kehua , Wang Liqun , Zhu Kangjie 
Published: October 2008

AbstractA facile route is described for the regioselective conjugation of organo‐soluble polymers onto chitosan under very mild conditions, using SCC as intermediates. SCC could be prepared simply by mixing chitosan acidic aqueous solution with SDS. PEG or PCL were then grafted to SCC using the NHS/DCC coupling method. In addition, the polymers were found to be linked to chitosan through the hydroxyl groups of chitosan when stoichiometric SCC was used as a precursor. SDS could be removed simply by either precipitating the solution of SCC‐graft‐polymer in DMSO into Tris aqueous solution or dialyzing against Tris solution.magnified image
Electrospun Non‐Woven Nanofibrous Hybrid Mats Based on Chitosan and PLA for Wound‐Dressing Applications
Authors: Ignatova Milena , Manolova Nevena , Markova Nadya , Rashkov Iliya 
Published: October 2008

AbstractContinuous defect‐free nanofibers containing chitosan (Ch) or quaternized chitosan (QCh) were successfully prepared by one‐step electrospinning of Ch or QCh solutions mixed with poly[(L‐lactide)‐co‐(d,l‐lactide)] in common solvent. XPS revealed the surface chemical composition of the bicomponent electrospun mats. Crosslinked Ch‐ and QCh‐containing nanofibers exhibited higher kill rates against bacteria S. aureus and E. coli than the corresponding solvent‐cast films. SEM observations showed that hybrid mats were very effective in suppressing the adhesion of pathogenic bacteria S. aureus. The hybrid nanofibers are promising for wound‐healing applications.magnified image
Functionalization of Multi‐Walled Carbon Nanotubes and their Application for Selective Isolation of Acidic Proteins
Authors: Du Zhuo , Yu Yong‐Liang , Wang Jian‐Hua 
Published: October 2008

AbstractA micro‐column packed with PDDA‐wrapped MWNTs in sequential injection system facilitates selective sorption of acidic protein species. Proteins adsorbed onto the PDDA‐MWNT composites are afterwards collected by elution with a citrate buffer as stripping reagent. With a sample loading volume of 2.0 mL and an eluent volume of 200 µL, a retention efficiency of 100% and a recovery of 90% are achieved for BSA in the range 6–120 µg, resulting in an enrichment factor of 14. A sampling frequency of 15 h−1 is achieved, along with a precision of 4.5% at 25 µg · mL−1 BSA. The practical applicability of this system is demonstrated by processing human whole blood for successive isolation of acidic proteins.magnified image
Synthesis of Au@SiO2 Core/Shell Nanoparticles and their Dispersion into an Acrylic Photocurable Formulation: Film Preparation and Characterization
Authors: Sangermano Marco , Perruchas Sandrine , Gacoin Thierry , Rizza Giancarlo 
Published: October 2008

AbstractAu core/silica shell (Au@SiO2) nanoparticles were synthesized by coating gold NPs with sol/gel silica in alcoholic solution. The alcoholic dispersion was added, in the range of 1–5 wt.‐%, to TPGDA and photocured by means of UV light. Transparent coatings were obtained and they can find suitable applications. It was shown that the NPs can restrict the segmental motion and decrease the free volume of the polymer network, with a consequent increase in glass transition temperature. TEM analysis put in evidence that the particles are well dispersed without any macroscopic agglomeration, and many particles are present as isolated particles.magnified image
Structural features and the persistence of acquired proteins
Authors: Narra Hema Prasad , Cordes Matthew H. J. , Ochman Howard 
Published: October 2008

AbstractORFan genes can constitute a large fraction of a bacterial genome, but due to their lack of homologs, their functions have remained largely unexplored. To determine if particular features of ORFan‐encoded proteins promote their presence in a genome, we analyzed properties of ORFans that originated over a broad evolutionary timescale. We also compared ORFan genes to another class of acquired genes, heterogeneous occurrence in prokaryotes (HOPs), which have homologs in other bacteria. A total of 54 ORFan and HOP genes selected from different phylogenetic depths in the Escherichia coli lineage were cloned, expressed, purified, and subjected to circular dichroism (CD) spectroscopy. A majority of genes could be expressed, but only 18 yielded sufficient soluble protein for spectral analysis. Of these, half were significantly α‐helical, three were predominantly β‐sheet, and six were of intermediate/indeterminate structure. Although a higher proportion of HOPs yielded soluble proteins with resolvable secondary structures, ORFans resembled HOPs with regard to most of the other features tested. Overall, we found that those ORFan and HOP genes that have persisted in the E. coli lineage were more likely to encode soluble and folded proteins, more likely to display environmental modulation of their gene expression, and by extrapolation, are more likely to be functional.
Electromechanical Behavior of Nanoscale Silver Coatings on PET Fibers
Authors: Amberg Martin , Grieder Kathrin , Barbadoro Pierluigi , Heuberger Manfred , Hegemann Dirk 
Published: October 2008

AbstractPlasma‐assisted deposition of silver films on PET mono‐ and multifilament fibers provides conductive fibers for wearable electronics. The nanoscale films were prepared in a continuously running low pressure plasma process using an ICM design for sputtering from a silver target combined with a prior RF cleaning step. The electrical resistance of the as‐deposited layers was measured in situ enabling an immediate feedback of the electrical properties, the film quality, applied Ag mass, and film thickness. The deposited quantity of Ag mass on the PET fibers was investigated by ICP‐OES and was correlated with the electrical resistance of the film. The metallized fibers showed excellent mechanical properties for wearable electronics as demonstrated by tensile properties measurement.magnified image
Evaluation of ELISA for imidacloprid detection in eastern hemlock (Tsuga canadensis) wood and needle tissues
Authors: Eisenback Brian M , Mullins Donald E , Salom Scott M , Kok Loke T 
Published: October 2008

AbstractBACKGROUND: Imidacloprid is the primary insecticide used against the exotic invasive insect hemlock woolly adelgid, Adelges tsugae Annand, a pest of eastern hemlock [Tsuga canadensis (L.) Carrière] trees in the eastern United States. A competitive enzyme‐linked immunosorbent assay (ELISA) was evaluated for quantification of imidacloprid in eastern hemlock wood and needle tissues.RESULTS: Matrix effects in the form of false positives and overestimated imidacloprid concentrations were observed in both wood and needle extracts. Tissues required a 100–1000‐fold dilution with water in order to reduce matrix effects. Standard curves in 1% wood or needle extract were not significantly different from standard curves prepared in water. Matrix effects were more pronounced at concentrations in the lower working range of the kit, with recovery of 5 µg L−1 imidacloprid more accurate than recovery of 0.2 µg L−1.CONCLUSION: ELISA remains a valuable tool for semi‐quantitative imidacloprid detection within the hemlock system because of its sensitivity, cost and ease of use. However, a 1000‐fold dilution of hemlock tissue extract is recommended to ensure accurate imidacloprid determinations. Copyright © 2008 Society of Chemical Industry
A dopant introduction device for atmospheric pressure photoionization with liquid chromatography/mass spectrometry
Authors: McCulloch Ross D. , Robb Damon B. , Blades Michael W. 
Published: October 2008

AbstractThis technical note describes in detail the fabrication, operation and characterization of a pneumatically driven dopant introduction device, with a solvent reservoir capacity of 300 mL. Dopant flow rates and stability for this device are governed by the simple regulation of gas pressure rather than the progression of a stepper motor and syringe diameter, as is the case for typical infusion pumps. The device has the potential to provide days or even weeks of continuous, uninterrupted dopant flow at rates commonly adopted for atmospheric pressure photoionization (APPI) experiments without the need to replenish the dopant supply. Although not a refined instrumental design, this device was developed as an alternative cost‐effective means of introducing stable dopant flow to an APPI source. The device was designed such that all components would be commercially available and easily procurable from common scientific part vendors. Figures and suggested part numbers are provided to allow those interested to fabricate similar devices to suit their individual experimental needs. Device characterization was performed while monitoring such factors as flow rate calibration, overall flow stability and reproducibility. In addition, a standard mixture of three polycyclic aromatic hydrocarbons was employed as a model sample for a typical reversed‐phase liquid chromatography/atmospheric pressure photoionization mass spectrometry (LC/APPI‐MS) application in order to demonstrate device performance. Copyright © 2008 John Wiley & Sons, Ltd.
High oxygen vacancy tin oxide synthesized by combustion chemical vapor deposition (CCVD)
Authors: Wu Qi‐Hui , Song Jie , Li Jincai 
Published: October 2008

AbstractTin oxide nanotentacles were synthesized by combustion chemical vapor deposition in air. Their surface composition and optical properties were then investigated using X‐ray photoelectron spectroscopy (XPS) and Raman spectroscopy. XPS core level spectra indicate that these nanotentacles are of high oxygen vacancy with chemical composition of about SnO1.6, which is also supported by the Sn Auger parameter. Besides SnO2, the optical properties of SnO were detected in Raman spectrum. Moreover, two new Raman peaks were found for the SnO2 phase because of the high oxygen vacancy concentration. Copyright © 2008 John Wiley & Sons, Ltd.
Adaptive radio resource allocation in OFDMA systems: a survey of the state‐of‐the‐art approaches
Authors: Chieochan Surachai , Hossain Ekram 
Published: October 2008

AbstractOrthogonal frequency division multiplexing (OFDM)‐based orthogonal frequency division multiple access (OFDMA) has emerged as a promising transmission technology for next generation wireless systems. In a multiuser scenario, adaptive radio resource allocation can significantly improve the performance of OFDMA systems. In this article, an overview of the major state‐of‐the‐art approaches to adaptive resource allocation in the OFDMA systems is provided. Several open research issues are outlined. Copyright © 2008 John Wiley & Sons, Ltd.
The Effects of Contact with Asians and Asian Americans on White American College Students: Attitudes, Awareness of Racial Discrimination, and Psychological Adjustment
Authors: Dinh Khanh T. , Weinstein Traci L. , Nemon Melissa , Rondeau Sara 
Published: October 2008

AbstractOn the basis of acculturation theory, explicating mutual influences between different cultural or ethnic groups coming into contact, this study focused “on the other side of acculturation” theory by examining the effects of intercultural contact with Asians and Asian Americans on the psychosocial experiences of White American college students. Participants (N = 315), undergraduates attending a public university located within the state of Massachusetts, completed a survey that assessed demographic and personal characteristics, acculturation (extent of intercultural contact with Asian people and Asian cultures), attitudes towards Asians and Asian Americans, awareness of institutional discrimination and blatant racial issues, and psychological distress. Results indicated that White American students' intercultural contact with Asians and Asian Americans contributed significant variance to the prediction of their attitudes towards this ethnic group and awareness of discrimination and racial issues, but not to psychological distress. This study provides implications for understanding mutual acculturative influences between different ethnic groups in the United States.